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QNTU | QNTU.sol | 0x4234f63b1d202f6c016ca3b6a0d41d7d85f17716 | Solidity | QNTU | contract QNTU is UpgradableToken, PausableToken {
/**
* @dev Constructor
*/
function QNTU(address[] _wallets, uint[] _amount)
public
{
require(_wallets.length == _amount.length);
symbol = "QNTU";
name = "QNTU Token";
decimals = 18;
uint num = 0;
uint length = _wallets.length;
uint multiplier = 10 ** uint(decimals);
for (uint i = 0; i < length; i++) {
num = _amount[i] * multiplier;
balanceOf[_wallets[i]] = num;
Transfer(0, _wallets[i], num);
totalSupply += num;
}
}
/**
* @dev Transfer token for a specified contract
* @param _to The address to transfer to.
* @param _value The amount to be transferred.
*/
function transferToContract(address _to, uint _value)
public
canTransfer
returns (bool)
{
require(_value > 0);
balanceOf[msg.sender] = balanceOf[msg.sender].sub(_value);
balanceOf[_to] = balanceOf[_to].add(_value);
ReceivingContract receiver = ReceivingContract(_to);
receiver.tokenFallback(msg.sender, _value);
Transfer(msg.sender, _to, _value);
return true;
}
} | /**
* @title QNTU 1.0 token
*/ | NatSpecMultiLine | transferToContract | function transferToContract(address _to, uint _value)
public
canTransfer
returns (bool)
{
require(_value > 0);
balanceOf[msg.sender] = balanceOf[msg.sender].sub(_value);
balanceOf[_to] = balanceOf[_to].add(_value);
ReceivingContract receiver = ReceivingContract(_to);
receiver.tokenFallback(msg.sender, _value);
Transfer(msg.sender, _to, _value);
return true;
}
| /**
* @dev Transfer token for a specified contract
* @param _to The address to transfer to.
* @param _value The amount to be transferred.
*/ | NatSpecMultiLine | v0.4.18+commit.9cf6e910 | bzzr://7b2322c984aba8e3e0ec830a52d277a41c06b6784a66d81856018224b990ea68 | {
"func_code_index": [
828,
1300
]
} | 6,300 |
|
BiosRewards | contracts/bios_rewards.sol | 0x3a9cd4c36b4ff8c51ddcf6bf6da927fec156460d | Solidity | BiosRewards | contract BiosRewards is LPTokenWrapper, IRewardDistributionRecipient, ERC677Receiver {
IERC20 public immutable rewardToken;
uint256 public immutable duration;
uint256 public periodFinish = 0;
uint256 public rewardRate = 0;
uint256 public lastUpdateTime;
uint256 public rewardPerTokenStored;
mapping(address => uint256) public userRewardPerTokenPaid;
mapping(address => uint256) public rewards;
event RewardAdded(uint256 reward);
event Staked(address indexed user, uint256 amount);
event Withdrawn(address indexed user, uint256 amount);
event RewardPaid(address indexed user, uint256 reward);
constructor(
address _rewardToken,
address _stakingToken,
uint256 _duration
)
public
LPTokenWrapper(_stakingToken)
{
rewardToken = IERC20(_rewardToken);
duration = _duration;
}
modifier updateReward(address account) {
rewardPerTokenStored = rewardPerToken();
lastUpdateTime = lastTimeRewardApplicable();
if (account != address(0)) {
rewards[account] = earned(account);
userRewardPerTokenPaid[account] = rewardPerTokenStored;
}
_;
}
function onTokenTransfer(address sender, uint256 amount, bytes memory)
public override updateReward(sender)
{
require(msg.sender == address(stakingToken), "!stakingToken");
super.stakeFor(sender, amount);
emit Staked(sender, amount);
}
function lastTimeRewardApplicable() public view returns (uint256) {
return Math.min(block.timestamp, periodFinish);
}
function rewardPerToken() public view returns (uint256) {
if (totalSupply() == 0) {
return rewardPerTokenStored;
}
return
rewardPerTokenStored.add(
lastTimeRewardApplicable()
.sub(lastUpdateTime)
.mul(rewardRate)
.mul(1e18)
.div(totalSupply())
);
}
function earned(address account) public view returns (uint256) {
return
balanceOf(account)
.mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
.div(1e18)
.add(rewards[account]);
}
// stake visibility is public as overriding LPTokenWrapper's stake() function
function stake(uint256 amount) public override updateReward(msg.sender) {
require(amount > 0, "Cannot stake 0");
super.stake(amount);
emit Staked(msg.sender, amount);
}
function withdraw(uint256 amount) public override updateReward(msg.sender) {
require(amount > 0, "Cannot withdraw 0");
super.withdraw(amount);
emit Withdrawn(msg.sender, amount);
}
function exit() external {
withdraw(balanceOf(msg.sender));
getReward();
}
function getReward() public updateReward(msg.sender) {
uint256 reward = earned(msg.sender);
if (reward > 0) {
rewards[msg.sender] = 0;
rewardToken.safeTransfer(msg.sender, reward);
emit RewardPaid(msg.sender, reward);
}
}
function notifyRewardAmount(uint256 reward)
external
override
onlyRewardDistribution
updateReward(address(0))
{
if (block.timestamp >= periodFinish) {
rewardRate = reward.div(duration);
} else {
uint256 remaining = periodFinish.sub(block.timestamp);
uint256 leftover = remaining.mul(rewardRate);
rewardRate = reward.add(leftover).div(duration);
}
lastUpdateTime = block.timestamp;
periodFinish = block.timestamp.add(duration);
emit RewardAdded(reward);
}
} | stake | function stake(uint256 amount) public override updateReward(msg.sender) {
require(amount > 0, "Cannot stake 0");
super.stake(amount);
emit Staked(msg.sender, amount);
}
| // stake visibility is public as overriding LPTokenWrapper's stake() function | LineComment | v0.6.12+commit.27d51765 | MIT | ipfs://a727dc1c76184231f41bd8a918df513f3f749ab9f38a9276cdea37864b11ac34 | {
"func_code_index": [
2471,
2676
]
} | 6,301 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SafeMath | contract SafeMath {
// Overflow protected math functions
/**
@dev returns the sum of _x and _y, asserts if the calculation overflows
@param _x value 1
@param _y value 2
@return sum
*/
function safeAdd(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x + _y;
require(z >= _x); //assert(z >= _x);
return z;
}
/**
@dev returns the difference of _x minus _y, asserts if the subtraction results in a negative number
@param _x minuend
@param _y subtrahend
@return difference
*/
function safeSub(uint256 _x, uint256 _y) internal pure returns (uint256) {
require(_x >= _y); //assert(_x >= _y);
return _x - _y;
}
/**
@dev returns the product of multiplying _x by _y, asserts if the calculation overflows
@param _x factor 1
@param _y factor 2
@return product
*/
function safeMul(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x * _y;
require(_x == 0 || z / _x == _y); //assert(_x == 0 || z / _x == _y);
return z;
}
function safeDiv(uint256 _x, uint256 _y)internal pure returns (uint256){
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return _x / _y;
}
function ceilDiv(uint256 _x, uint256 _y)internal pure returns (uint256){
return (_x + _y - 1) / _y;
}
} | safeAdd | function safeAdd(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x + _y;
require(z >= _x); //assert(z >= _x);
return z;
}
| /**
@dev returns the sum of _x and _y, asserts if the calculation overflows
@param _x value 1
@param _y value 2
@return sum
*/ | NatSpecMultiLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
246,
434
]
} | 6,302 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SafeMath | contract SafeMath {
// Overflow protected math functions
/**
@dev returns the sum of _x and _y, asserts if the calculation overflows
@param _x value 1
@param _y value 2
@return sum
*/
function safeAdd(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x + _y;
require(z >= _x); //assert(z >= _x);
return z;
}
/**
@dev returns the difference of _x minus _y, asserts if the subtraction results in a negative number
@param _x minuend
@param _y subtrahend
@return difference
*/
function safeSub(uint256 _x, uint256 _y) internal pure returns (uint256) {
require(_x >= _y); //assert(_x >= _y);
return _x - _y;
}
/**
@dev returns the product of multiplying _x by _y, asserts if the calculation overflows
@param _x factor 1
@param _y factor 2
@return product
*/
function safeMul(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x * _y;
require(_x == 0 || z / _x == _y); //assert(_x == 0 || z / _x == _y);
return z;
}
function safeDiv(uint256 _x, uint256 _y)internal pure returns (uint256){
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return _x / _y;
}
function ceilDiv(uint256 _x, uint256 _y)internal pure returns (uint256){
return (_x + _y - 1) / _y;
}
} | safeSub | function safeSub(uint256 _x, uint256 _y) internal pure returns (uint256) {
require(_x >= _y); //assert(_x >= _y);
return _x - _y;
}
| /**
@dev returns the difference of _x minus _y, asserts if the subtraction results in a negative number
@param _x minuend
@param _y subtrahend
@return difference
*/ | NatSpecMultiLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
656,
822
]
} | 6,303 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SafeMath | contract SafeMath {
// Overflow protected math functions
/**
@dev returns the sum of _x and _y, asserts if the calculation overflows
@param _x value 1
@param _y value 2
@return sum
*/
function safeAdd(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x + _y;
require(z >= _x); //assert(z >= _x);
return z;
}
/**
@dev returns the difference of _x minus _y, asserts if the subtraction results in a negative number
@param _x minuend
@param _y subtrahend
@return difference
*/
function safeSub(uint256 _x, uint256 _y) internal pure returns (uint256) {
require(_x >= _y); //assert(_x >= _y);
return _x - _y;
}
/**
@dev returns the product of multiplying _x by _y, asserts if the calculation overflows
@param _x factor 1
@param _y factor 2
@return product
*/
function safeMul(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x * _y;
require(_x == 0 || z / _x == _y); //assert(_x == 0 || z / _x == _y);
return z;
}
function safeDiv(uint256 _x, uint256 _y)internal pure returns (uint256){
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return _x / _y;
}
function ceilDiv(uint256 _x, uint256 _y)internal pure returns (uint256){
return (_x + _y - 1) / _y;
}
} | safeMul | function safeMul(uint256 _x, uint256 _y) internal pure returns (uint256) {
uint256 z = _x * _y;
require(_x == 0 || z / _x == _y); //assert(_x == 0 || z / _x == _y);
return z;
}
| /**
@dev returns the product of multiplying _x by _y, asserts if the calculation overflows
@param _x factor 1
@param _y factor 2
@return product
*/ | NatSpecMultiLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
1027,
1247
]
} | 6,304 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | balanceOf | function balanceOf(address _owner) public view returns (uint256 balance) {
eturn balances[_owner];
| /// @param _owner The address from which the balance will be retrieved
/// @return The balance | NatSpecSingleLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
773,
885
]
} | 6,305 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | transfer | function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
quire(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
lances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
it Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
turn true;
| /// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not | NatSpecSingleLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
1122,
1937
]
} | 6,306 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | transferFrom | function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
| /// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not | NatSpecSingleLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
2260,
3061
]
} | 6,307 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | approve | function approve(address _spender, uint256 _value) public returns (bool success) {
quire(balances[msg.sender] >= _value);
lowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
turn true;
| /// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not | NatSpecSingleLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
3351,
3602
]
} | 6,308 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | allowance | function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
| /// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent | NatSpecSingleLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
3811,
3957
]
} | 6,309 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | _burn | function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
| /// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned | NatSpecSingleLine | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
4107,
4309
]
} | 6,310 |
||
SBToken | SBToken.sol | 0xcadb96858fe496bb6309622f9023ba2defb5d540 | Solidity | SBToken | contract SBToken is SafeMath {
mapping (address => uint256) balances;
address public owner;
string public name;
string public symbol;
uint8 public decimals = 18;
// total amount of tokens
uint256 public totalSupply;
// `allowed` tracks any extra transfer rights as in all ERC20 tokens
mapping (address => mapping (address => uint256)) allowed;
constructor() public {
uint256 initialSupply = 10000000000;
owner = msg.sender;
totalSupply = initialSupply * 10 ** uint256(decimals);
balances[owner] = totalSupply;
name = "SBToken";
symbol = "SBC";
}
/// @param _owner The address from which the balance will be retrieved
/// @return The balance
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
/// @notice send `_value` token to `_to` from `msg.sender`
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transfer(address _to, uint256 _value) public returns (bool success) {
require(_value > 0 ); // Check send token value > 0;
require(balances[msg.sender] >= _value); // Check if the sender has enough
require(balances[_to] + _value > balances[_to]); // Check for overflows
balances[msg.sender] = safeSub(balances[msg.sender], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(msg.sender, _to, _value); // Notify anyone listening that this transfer took place
return true;
}
/// @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
/// @param _from The address of the sender
/// @param _to The address of the recipient
/// @param _value The amount of token to be transferred
/// @return Whether the transfer was successful or not
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(balances[_from] >= _value); // Check if the sender has enough
require(balances[_to] + _value >= balances[_to]); // Check for overflows
require(_value <= allowed[_from][msg.sender]); // Check allowance
balances[_from] = safeSub(balances[_from], _value); // Subtract from the sender
balances[_to] = safeAdd(balances[_to], _value); // Add the same to the recipient
allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
if(_to == address(0)) {
_burn(_to, _value);
}
emit Transfer(_from, _to, _value);
return true;
}
/// @notice `msg.sender` approves `_spender` to spend `_value` tokens
/// @param _spender The address of the account able to transfer the tokens
/// @param _value The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _value) public returns (bool success) {
require(balances[msg.sender] >= _value);
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/// @param _owner The address of the account owning tokens
/// @param _spender The address of the account able to transfer the tokens
/// @return Amount of remaining tokens allowed to spent
function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/// @param _account must be the zero address and must have at least `amount` tokens
/// @param _value The amount of tokens to been burned
function _burn(address _account, uint256 _value) internal {
require(_account == address(0), "ERC20: burn to the zero address");
totalSupply = safeSub(totalSupply, _value);
}
/* This unnamed function is called whenever someone tries to send ether to it */
function () external {
revert(); // Prevents accidental sending of ether
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
} | function () external {
revert(); // Prevents accidental sending of ether
}
| /* This unnamed function is called whenever someone tries to send ether to it */ | Comment | v0.5.11+commit.c082d0b4 | MIT | bzzr://3bb88cafcaa3b0ddf7ddae8f59f2c48b16b66de610e999428668f7d96ef7fdda | {
"func_code_index": [
4396,
4493
]
} | 6,311 |
|||
OwnedUpgradeabilityProxy | OwnedUpgradeabilityProxy.sol | 0x895b5fe62645c47d37fe5cc3bc9246621f5e47bb | Solidity | OwnedUpgradeabilityProxy | contract OwnedUpgradeabilityProxy is UpgradeabilityProxy {
/**
* @dev Event to show ownership has been transferred
* @param previousOwner representing the address of the previous owner
* @param newOwner representing the address of the new owner
*/
event ProxyOwnershipTransferred(address previousOwner, address newOwner);
// Storage position of the owner of the contract
bytes32 private constant proxyOwnerPosition = keccak256("com.d3ledger.proxy.owner");
/**
* @dev the constructor sets the original owner of the contract to the sender account.
*/
constructor() public {
setUpgradeabilityOwner(msg.sender);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/
function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/
function upgradeToAndCall(address implementation, bytes memory data) payable public onlyProxyOwner {
upgradeTo(implementation);
(bool success,) = address(this).call.value(msg.value)(data);
require(success);
}
} | /**
* @title OwnedUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with basic authorization control functionalities
*/ | NatSpecMultiLine | proxyOwner | function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
| /**
* @dev Tells the address of the owner
* @return the address of the owner
*/ | NatSpecMultiLine | v0.5.9+commit.e560f70d | Apache-2.0 | bzzr://8743d7295a9e30092dbf278b16cce18ba70ce00b7984f4a5c5d0f58be82ceaab | {
"func_code_index": [
891,
1051
]
} | 6,312 |
OwnedUpgradeabilityProxy | OwnedUpgradeabilityProxy.sol | 0x895b5fe62645c47d37fe5cc3bc9246621f5e47bb | Solidity | OwnedUpgradeabilityProxy | contract OwnedUpgradeabilityProxy is UpgradeabilityProxy {
/**
* @dev Event to show ownership has been transferred
* @param previousOwner representing the address of the previous owner
* @param newOwner representing the address of the new owner
*/
event ProxyOwnershipTransferred(address previousOwner, address newOwner);
// Storage position of the owner of the contract
bytes32 private constant proxyOwnerPosition = keccak256("com.d3ledger.proxy.owner");
/**
* @dev the constructor sets the original owner of the contract to the sender account.
*/
constructor() public {
setUpgradeabilityOwner(msg.sender);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/
function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/
function upgradeToAndCall(address implementation, bytes memory data) payable public onlyProxyOwner {
upgradeTo(implementation);
(bool success,) = address(this).call.value(msg.value)(data);
require(success);
}
} | /**
* @title OwnedUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with basic authorization control functionalities
*/ | NatSpecMultiLine | setUpgradeabilityOwner | function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
| /**
* @dev Sets the address of the owner
*/ | NatSpecMultiLine | v0.5.9+commit.e560f70d | Apache-2.0 | bzzr://8743d7295a9e30092dbf278b16cce18ba70ce00b7984f4a5c5d0f58be82ceaab | {
"func_code_index": [
1105,
1278
]
} | 6,313 |
OwnedUpgradeabilityProxy | OwnedUpgradeabilityProxy.sol | 0x895b5fe62645c47d37fe5cc3bc9246621f5e47bb | Solidity | OwnedUpgradeabilityProxy | contract OwnedUpgradeabilityProxy is UpgradeabilityProxy {
/**
* @dev Event to show ownership has been transferred
* @param previousOwner representing the address of the previous owner
* @param newOwner representing the address of the new owner
*/
event ProxyOwnershipTransferred(address previousOwner, address newOwner);
// Storage position of the owner of the contract
bytes32 private constant proxyOwnerPosition = keccak256("com.d3ledger.proxy.owner");
/**
* @dev the constructor sets the original owner of the contract to the sender account.
*/
constructor() public {
setUpgradeabilityOwner(msg.sender);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/
function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/
function upgradeToAndCall(address implementation, bytes memory data) payable public onlyProxyOwner {
upgradeTo(implementation);
(bool success,) = address(this).call.value(msg.value)(data);
require(success);
}
} | /**
* @title OwnedUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with basic authorization control functionalities
*/ | NatSpecMultiLine | transferProxyOwnership | function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
| /**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/ | NatSpecMultiLine | v0.5.9+commit.e560f70d | Apache-2.0 | bzzr://8743d7295a9e30092dbf278b16cce18ba70ce00b7984f4a5c5d0f58be82ceaab | {
"func_code_index": [
1437,
1651
]
} | 6,314 |
OwnedUpgradeabilityProxy | OwnedUpgradeabilityProxy.sol | 0x895b5fe62645c47d37fe5cc3bc9246621f5e47bb | Solidity | OwnedUpgradeabilityProxy | contract OwnedUpgradeabilityProxy is UpgradeabilityProxy {
/**
* @dev Event to show ownership has been transferred
* @param previousOwner representing the address of the previous owner
* @param newOwner representing the address of the new owner
*/
event ProxyOwnershipTransferred(address previousOwner, address newOwner);
// Storage position of the owner of the contract
bytes32 private constant proxyOwnerPosition = keccak256("com.d3ledger.proxy.owner");
/**
* @dev the constructor sets the original owner of the contract to the sender account.
*/
constructor() public {
setUpgradeabilityOwner(msg.sender);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/
function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/
function upgradeToAndCall(address implementation, bytes memory data) payable public onlyProxyOwner {
upgradeTo(implementation);
(bool success,) = address(this).call.value(msg.value)(data);
require(success);
}
} | /**
* @title OwnedUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with basic authorization control functionalities
*/ | NatSpecMultiLine | upgradeTo | function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
| /**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/ | NatSpecMultiLine | v0.5.9+commit.e560f70d | Apache-2.0 | bzzr://8743d7295a9e30092dbf278b16cce18ba70ce00b7984f4a5c5d0f58be82ceaab | {
"func_code_index": [
1832,
1936
]
} | 6,315 |
OwnedUpgradeabilityProxy | OwnedUpgradeabilityProxy.sol | 0x895b5fe62645c47d37fe5cc3bc9246621f5e47bb | Solidity | OwnedUpgradeabilityProxy | contract OwnedUpgradeabilityProxy is UpgradeabilityProxy {
/**
* @dev Event to show ownership has been transferred
* @param previousOwner representing the address of the previous owner
* @param newOwner representing the address of the new owner
*/
event ProxyOwnershipTransferred(address previousOwner, address newOwner);
// Storage position of the owner of the contract
bytes32 private constant proxyOwnerPosition = keccak256("com.d3ledger.proxy.owner");
/**
* @dev the constructor sets the original owner of the contract to the sender account.
*/
constructor() public {
setUpgradeabilityOwner(msg.sender);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/
function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/
function upgradeToAndCall(address implementation, bytes memory data) payable public onlyProxyOwner {
upgradeTo(implementation);
(bool success,) = address(this).call.value(msg.value)(data);
require(success);
}
} | /**
* @title OwnedUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with basic authorization control functionalities
*/ | NatSpecMultiLine | upgradeToAndCall | function upgradeToAndCall(address implementation, bytes memory data) payable public onlyProxyOwner {
upgradeTo(implementation);
(bool success,) = address(this).call.value(msg.value)(data);
require(success);
}
| /**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/ | NatSpecMultiLine | v0.5.9+commit.e560f70d | Apache-2.0 | bzzr://8743d7295a9e30092dbf278b16cce18ba70ce00b7984f4a5c5d0f58be82ceaab | {
"func_code_index": [
2402,
2626
]
} | 6,316 |
GrowToken | GrowToken.sol | 0x832ec40433b457028a1d27434f3b9fdf81aaecbe | Solidity | SafeMath | library SafeMath {
/*
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
if (a == 0) {
return 0;
}
c = a * b;
assert(c / a == b);
return c;
}
/*
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
/*
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/*
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
c = a + b;
assert(c >= a);
return c;
}
} | /*
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/ | Comment | mul | function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
if (a == 0) {
return 0;
}
c = a * b;
assert(c / a == b);
return c;
}
| /*
* @dev Multiplies two numbers, throws on overflow.
*/ | Comment | v0.4.25+commit.59dbf8f1 | bzzr://be538c703fe0f7390dd7c96b80dddbd44a767561698c802ea73aae1115890ad5 | {
"func_code_index": [
94,
301
]
} | 6,317 |
|
GrowToken | GrowToken.sol | 0x832ec40433b457028a1d27434f3b9fdf81aaecbe | Solidity | SafeMath | library SafeMath {
/*
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
if (a == 0) {
return 0;
}
c = a * b;
assert(c / a == b);
return c;
}
/*
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
/*
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/*
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
c = a + b;
assert(c >= a);
return c;
}
} | /*
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/ | Comment | div | function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
| /*
* @dev Integer division of two numbers, truncating the quotient.
*/ | Comment | v0.4.25+commit.59dbf8f1 | bzzr://be538c703fe0f7390dd7c96b80dddbd44a767561698c802ea73aae1115890ad5 | {
"func_code_index": [
390,
690
]
} | 6,318 |
|
GrowToken | GrowToken.sol | 0x832ec40433b457028a1d27434f3b9fdf81aaecbe | Solidity | SafeMath | library SafeMath {
/*
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
if (a == 0) {
return 0;
}
c = a * b;
assert(c / a == b);
return c;
}
/*
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
/*
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/*
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
c = a + b;
assert(c >= a);
return c;
}
} | /*
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/ | Comment | sub | function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
| /*
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/ | Comment | v0.4.25+commit.59dbf8f1 | bzzr://be538c703fe0f7390dd7c96b80dddbd44a767561698c802ea73aae1115890ad5 | {
"func_code_index": [
809,
937
]
} | 6,319 |
|
GrowToken | GrowToken.sol | 0x832ec40433b457028a1d27434f3b9fdf81aaecbe | Solidity | SafeMath | library SafeMath {
/*
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
if (a == 0) {
return 0;
}
c = a * b;
assert(c / a == b);
return c;
}
/*
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
/*
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/*
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
c = a + b;
assert(c >= a);
return c;
}
} | /*
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/ | Comment | add | function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
c = a + b;
assert(c >= a);
return c;
}
| /*
* @dev Adds two numbers, throws on overflow.
*/ | Comment | v0.4.25+commit.59dbf8f1 | bzzr://be538c703fe0f7390dd7c96b80dddbd44a767561698c802ea73aae1115890ad5 | {
"func_code_index": [
1006,
1152
]
} | 6,320 |
|
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BControllerInterface | contract BControllerInterface {
/// @notice Indicator that this is a BController contract (for inspection)
bool public constant isBController = true;
/*** Assets You Are In ***/
function enterMarkets(address[] calldata bTokens) external returns (uint[] memory);
function exitMarket(address bToken) external returns (uint);
/*** Policy Hooks ***/
function mintAllowed(address bToken, address minter, uint mintAmount) external returns (uint);
function mintVerify(address bToken, address minter, uint mintAmount, uint mintTokens) external;
function redeemAllowed(address bToken, address redeemer, uint redeemTokens) external returns (uint);
function redeemVerify(address bToken, address redeemer, uint redeemAmount, uint redeemTokens) external;
function borrowAllowed(address bToken, address borrower, uint borrowAmount) external returns (uint);
function borrowVerify(address bToken, address borrower, uint borrowAmount) external;
function repayBorrowAllowed(address bToken, address payer, address borrower, uint repayAmount) external returns (uint);
function repayBorrowVerify(address bToken, address payer, address borrower, uint repayAmount, uint borrowerIndex) external;
function liquidateBorrowAllowed(address bTokenBorrowed, address bTokenCollateral, address liquidator, address borrower, uint repayAmount) external returns (uint);
function liquidateBorrowVerify(address bTokenBorrowed, address bTokenCollateral, address liquidator, address borrower, uint repayAmount, uint seizeTokens) external;
function seizeAllowed(address bTokenCollateral, address bTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external returns (uint);
function seizeVerify(address bTokenCollateral, address bTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external;
function transferAllowed(address bToken, address src, address dst, uint transferTokens) external returns (uint);
function transferVerify(address bToken, address src, address dst, uint transferTokens) external;
/*** Liquidity/Liquidation Calculations ***/
function liquidateCalculateSeizeTokens(address bTokenBorrowed, address bTokenCollateral, uint repayAmount) external view returns (uint, uint);
} | /**
* @title Bird's BController Interface
*/ | NatSpecMultiLine | enterMarkets | function enterMarkets(address[] calldata bTokens) external returns (uint[] memory);
| /*** Assets You Are In ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
192,
279
]
} | 6,321 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BControllerInterface | contract BControllerInterface {
/// @notice Indicator that this is a BController contract (for inspection)
bool public constant isBController = true;
/*** Assets You Are In ***/
function enterMarkets(address[] calldata bTokens) external returns (uint[] memory);
function exitMarket(address bToken) external returns (uint);
/*** Policy Hooks ***/
function mintAllowed(address bToken, address minter, uint mintAmount) external returns (uint);
function mintVerify(address bToken, address minter, uint mintAmount, uint mintTokens) external;
function redeemAllowed(address bToken, address redeemer, uint redeemTokens) external returns (uint);
function redeemVerify(address bToken, address redeemer, uint redeemAmount, uint redeemTokens) external;
function borrowAllowed(address bToken, address borrower, uint borrowAmount) external returns (uint);
function borrowVerify(address bToken, address borrower, uint borrowAmount) external;
function repayBorrowAllowed(address bToken, address payer, address borrower, uint repayAmount) external returns (uint);
function repayBorrowVerify(address bToken, address payer, address borrower, uint repayAmount, uint borrowerIndex) external;
function liquidateBorrowAllowed(address bTokenBorrowed, address bTokenCollateral, address liquidator, address borrower, uint repayAmount) external returns (uint);
function liquidateBorrowVerify(address bTokenBorrowed, address bTokenCollateral, address liquidator, address borrower, uint repayAmount, uint seizeTokens) external;
function seizeAllowed(address bTokenCollateral, address bTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external returns (uint);
function seizeVerify(address bTokenCollateral, address bTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external;
function transferAllowed(address bToken, address src, address dst, uint transferTokens) external returns (uint);
function transferVerify(address bToken, address src, address dst, uint transferTokens) external;
/*** Liquidity/Liquidation Calculations ***/
function liquidateCalculateSeizeTokens(address bTokenBorrowed, address bTokenCollateral, uint repayAmount) external view returns (uint, uint);
} | /**
* @title Bird's BController Interface
*/ | NatSpecMultiLine | mintAllowed | function mintAllowed(address bToken, address minter, uint mintAmount) external returns (uint);
| /*** Policy Hooks ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
374,
472
]
} | 6,322 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BControllerInterface | contract BControllerInterface {
/// @notice Indicator that this is a BController contract (for inspection)
bool public constant isBController = true;
/*** Assets You Are In ***/
function enterMarkets(address[] calldata bTokens) external returns (uint[] memory);
function exitMarket(address bToken) external returns (uint);
/*** Policy Hooks ***/
function mintAllowed(address bToken, address minter, uint mintAmount) external returns (uint);
function mintVerify(address bToken, address minter, uint mintAmount, uint mintTokens) external;
function redeemAllowed(address bToken, address redeemer, uint redeemTokens) external returns (uint);
function redeemVerify(address bToken, address redeemer, uint redeemAmount, uint redeemTokens) external;
function borrowAllowed(address bToken, address borrower, uint borrowAmount) external returns (uint);
function borrowVerify(address bToken, address borrower, uint borrowAmount) external;
function repayBorrowAllowed(address bToken, address payer, address borrower, uint repayAmount) external returns (uint);
function repayBorrowVerify(address bToken, address payer, address borrower, uint repayAmount, uint borrowerIndex) external;
function liquidateBorrowAllowed(address bTokenBorrowed, address bTokenCollateral, address liquidator, address borrower, uint repayAmount) external returns (uint);
function liquidateBorrowVerify(address bTokenBorrowed, address bTokenCollateral, address liquidator, address borrower, uint repayAmount, uint seizeTokens) external;
function seizeAllowed(address bTokenCollateral, address bTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external returns (uint);
function seizeVerify(address bTokenCollateral, address bTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external;
function transferAllowed(address bToken, address src, address dst, uint transferTokens) external returns (uint);
function transferVerify(address bToken, address src, address dst, uint transferTokens) external;
/*** Liquidity/Liquidation Calculations ***/
function liquidateCalculateSeizeTokens(address bTokenBorrowed, address bTokenCollateral, uint repayAmount) external view returns (uint, uint);
} | /**
* @title Bird's BController Interface
*/ | NatSpecMultiLine | liquidateCalculateSeizeTokens | function liquidateCalculateSeizeTokens(address bTokenBorrowed, address bTokenCollateral, uint repayAmount) external view returns (uint, uint);
| /*** Liquidity/Liquidation Calculations ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2141,
2287
]
} | 6,323 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | InterestRateModel | contract InterestRateModel {
/// @notice Indicator that this is an InterestRateModel contract (for inspection)
bool public constant isInterestRateModel = true;
/**
* @notice Calculates the current borrow interest rate per block
* @param cash The total amount of cash the market has
* @param borrows The total amount of borrows the market has outstanding
* @param reserves The total amount of reserves the market has
* @return The borrow rate per block (as a percentage, and scaled by 1e18)
*/
function getBorrowRate(uint cash, uint borrows, uint reserves) external view returns (uint);
/**
* @notice Calculates the current supply interest rate per block
* @param cash The total amount of cash the market has
* @param borrows The total amount of borrows the market has outstanding
* @param reserves The total amount of reserves the market has
* @param reserveFactorMantissa The current reserve factor the market has
* @return The supply rate per block (as a percentage, and scaled by 1e18)
*/
function getSupplyRate(uint cash, uint borrows, uint reserves, uint reserveFactorMantissa) external view returns (uint);
} | /**
* @title Bird's InterestRateModel Interface
*/ | NatSpecMultiLine | getBorrowRate | function getBorrowRate(uint cash, uint borrows, uint reserves) external view returns (uint);
| /**
* @notice Calculates the current borrow interest rate per block
* @param cash The total amount of cash the market has
* @param borrows The total amount of borrows the market has outstanding
* @param reserves The total amount of reserves the market has
* @return The borrow rate per block (as a percentage, and scaled by 1e18)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
542,
638
]
} | 6,324 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | InterestRateModel | contract InterestRateModel {
/// @notice Indicator that this is an InterestRateModel contract (for inspection)
bool public constant isInterestRateModel = true;
/**
* @notice Calculates the current borrow interest rate per block
* @param cash The total amount of cash the market has
* @param borrows The total amount of borrows the market has outstanding
* @param reserves The total amount of reserves the market has
* @return The borrow rate per block (as a percentage, and scaled by 1e18)
*/
function getBorrowRate(uint cash, uint borrows, uint reserves) external view returns (uint);
/**
* @notice Calculates the current supply interest rate per block
* @param cash The total amount of cash the market has
* @param borrows The total amount of borrows the market has outstanding
* @param reserves The total amount of reserves the market has
* @param reserveFactorMantissa The current reserve factor the market has
* @return The supply rate per block (as a percentage, and scaled by 1e18)
*/
function getSupplyRate(uint cash, uint borrows, uint reserves, uint reserveFactorMantissa) external view returns (uint);
} | /**
* @title Bird's InterestRateModel Interface
*/ | NatSpecMultiLine | getSupplyRate | function getSupplyRate(uint cash, uint borrows, uint reserves, uint reserveFactorMantissa) external view returns (uint);
| /**
* @notice Calculates the current supply interest rate per block
* @param cash The total amount of cash the market has
* @param borrows The total amount of borrows the market has outstanding
* @param reserves The total amount of reserves the market has
* @param reserveFactorMantissa The current reserve factor the market has
* @return The supply rate per block (as a percentage, and scaled by 1e18)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1092,
1216
]
} | 6,325 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BTokenInterface | contract BTokenInterface is BTokenStorage {
/**
* @notice Indicator that this is a BToken contract (for inspection)
*/
bool public constant isBToken = true;
/*** Market Events ***/
/**
* @notice Event emitted when interest is accrued
*/
event AccrueInterestToken(uint cashPrior, uint interestAccumulated, uint borrowIndex, uint totalBorrows);
/**
* @notice Event emitted when tokens are minted
*/
event MintToken(address minter, uint mintAmount, uint mintTokens);
/**
* @notice Event emitted when tokens are redeemed
*/
event RedeemToken(address redeemer, uint redeemAmount, uint redeemTokens);
/**
* @notice Event emitted when underlying is borrowed
*/
event BorrowToken(address borrower, uint borrowAmount, uint accountBorrows, uint totalBorrows);
/**
* @notice Event emitted when a borrow is repaid
*/
event RepayBorrowToken(address payer, address borrower, uint repayAmount, uint accountBorrows, uint totalBorrows);
/**
* @notice Event emitted when a borrow is liquidated
*/
event LiquidateBorrowToken(address liquidator, address borrower, uint repayAmount, address bTokenCollateral, uint seizeTokens);
/*** Admin Events ***/
/**
* @notice Event emitted when pendingAdmin is changed
*/
event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin);
/**
* @notice Event emitted when pendingAdmin is accepted, which means admin is updated
*/
event NewAdmin(address oldAdmin, address newAdmin);
/**
* @notice Event emitted when bController is changed
*/
event NewBController(BControllerInterface oldBController, BControllerInterface newBController);
/**
* @notice Event emitted when interestRateModel is changed
*/
event NewMarketTokenInterestRateModel(InterestRateModel oldInterestRateModel, InterestRateModel newInterestRateModel);
/**
* @notice Event emitted when the reserve factor is changed
*/
event NewTokenReserveFactor(uint oldReserveFactorMantissa, uint newReserveFactorMantissa);
/**
* @notice Event emitted when the reserves are added
*/
event ReservesAdded(address benefactor, uint addAmount, uint newTotalReserves);
/**
* @notice Event emitted when the reserves are reduced
*/
event ReservesReduced(address admin, uint reduceAmount, uint newTotalReserves);
/**
* @notice EIP20 Transfer event
*/
event Transfer(address indexed from, address indexed to, uint amount);
/**
* @notice EIP20 Approval event
*/
event Approval(address indexed owner, address indexed spender, uint amount);
/**
* @notice Failure event
*/
event Failure(uint error, uint info, uint detail);
/*** User Interface ***/
function transfer(address dst, uint amount) external returns (bool);
function transferFrom(address src, address dst, uint amount) external returns (bool);
function approve(address spender, uint amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function balanceOfUnderlying(address owner) external returns (uint);
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint);
function borrowRatePerBlock() external view returns (uint);
function supplyRatePerBlock() external view returns (uint);
function totalBorrowsCurrent() external returns (uint);
function borrowBalanceCurrent(address account) external returns (uint);
function borrowBalanceStored(address account) public view returns (uint);
function exchangeRateCurrent() public returns (uint);
function exchangeRateStored() public view returns (uint);
function getCash() external view returns (uint);
function accrueInterest() public returns (uint);
function seize(address liquidator, address borrower, uint seizeTokens) external returns (uint);
/*** Admin Functions ***/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint);
function _acceptAdmin() external returns (uint);
function _setBController(BControllerInterface newBController) public returns (uint);
function _setReserveFactor(uint newReserveFactorMantissa) external returns (uint);
function _reduceReserves(uint reduceAmount) external returns (uint);
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint);
} | /**
* @title Bird's BToken Interface
*/ | NatSpecMultiLine | transfer | function transfer(address dst, uint amount) external returns (bool);
| /*** User Interface ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2854,
2926
]
} | 6,326 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BTokenInterface | contract BTokenInterface is BTokenStorage {
/**
* @notice Indicator that this is a BToken contract (for inspection)
*/
bool public constant isBToken = true;
/*** Market Events ***/
/**
* @notice Event emitted when interest is accrued
*/
event AccrueInterestToken(uint cashPrior, uint interestAccumulated, uint borrowIndex, uint totalBorrows);
/**
* @notice Event emitted when tokens are minted
*/
event MintToken(address minter, uint mintAmount, uint mintTokens);
/**
* @notice Event emitted when tokens are redeemed
*/
event RedeemToken(address redeemer, uint redeemAmount, uint redeemTokens);
/**
* @notice Event emitted when underlying is borrowed
*/
event BorrowToken(address borrower, uint borrowAmount, uint accountBorrows, uint totalBorrows);
/**
* @notice Event emitted when a borrow is repaid
*/
event RepayBorrowToken(address payer, address borrower, uint repayAmount, uint accountBorrows, uint totalBorrows);
/**
* @notice Event emitted when a borrow is liquidated
*/
event LiquidateBorrowToken(address liquidator, address borrower, uint repayAmount, address bTokenCollateral, uint seizeTokens);
/*** Admin Events ***/
/**
* @notice Event emitted when pendingAdmin is changed
*/
event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin);
/**
* @notice Event emitted when pendingAdmin is accepted, which means admin is updated
*/
event NewAdmin(address oldAdmin, address newAdmin);
/**
* @notice Event emitted when bController is changed
*/
event NewBController(BControllerInterface oldBController, BControllerInterface newBController);
/**
* @notice Event emitted when interestRateModel is changed
*/
event NewMarketTokenInterestRateModel(InterestRateModel oldInterestRateModel, InterestRateModel newInterestRateModel);
/**
* @notice Event emitted when the reserve factor is changed
*/
event NewTokenReserveFactor(uint oldReserveFactorMantissa, uint newReserveFactorMantissa);
/**
* @notice Event emitted when the reserves are added
*/
event ReservesAdded(address benefactor, uint addAmount, uint newTotalReserves);
/**
* @notice Event emitted when the reserves are reduced
*/
event ReservesReduced(address admin, uint reduceAmount, uint newTotalReserves);
/**
* @notice EIP20 Transfer event
*/
event Transfer(address indexed from, address indexed to, uint amount);
/**
* @notice EIP20 Approval event
*/
event Approval(address indexed owner, address indexed spender, uint amount);
/**
* @notice Failure event
*/
event Failure(uint error, uint info, uint detail);
/*** User Interface ***/
function transfer(address dst, uint amount) external returns (bool);
function transferFrom(address src, address dst, uint amount) external returns (bool);
function approve(address spender, uint amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function balanceOfUnderlying(address owner) external returns (uint);
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint);
function borrowRatePerBlock() external view returns (uint);
function supplyRatePerBlock() external view returns (uint);
function totalBorrowsCurrent() external returns (uint);
function borrowBalanceCurrent(address account) external returns (uint);
function borrowBalanceStored(address account) public view returns (uint);
function exchangeRateCurrent() public returns (uint);
function exchangeRateStored() public view returns (uint);
function getCash() external view returns (uint);
function accrueInterest() public returns (uint);
function seize(address liquidator, address borrower, uint seizeTokens) external returns (uint);
/*** Admin Functions ***/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint);
function _acceptAdmin() external returns (uint);
function _setBController(BControllerInterface newBController) public returns (uint);
function _setReserveFactor(uint newReserveFactorMantissa) external returns (uint);
function _reduceReserves(uint reduceAmount) external returns (uint);
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint);
} | /**
* @title Bird's BToken Interface
*/ | NatSpecMultiLine | _setPendingAdmin | function _setPendingAdmin(address payable newPendingAdmin) external returns (uint);
| /*** Admin Functions ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
4116,
4203
]
} | 6,327 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BErc20Interface | contract BErc20Interface is BErc20Storage {
/*** User Interface ***/
function mint(uint mintAmount) external returns (uint);
function redeem(uint redeemTokens) external returns (uint);
function redeemUnderlying(uint redeemAmount) external returns (uint);
function borrow(uint borrowAmount) external returns (uint);
function repayBorrow(uint repayAmount) external returns (uint);
function repayBorrowBehalf(address borrower, uint repayAmount) external returns (uint);
function liquidateBorrow(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) external returns (uint);
/*** Admin Functions ***/
function _addReserves(uint addAmount) external returns (uint);
} | /**
* @title Bird's BErc20 Interface
*/ | NatSpecMultiLine | mint | function mint(uint mintAmount) external returns (uint);
| /*** User Interface ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
75,
134
]
} | 6,328 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BErc20Interface | contract BErc20Interface is BErc20Storage {
/*** User Interface ***/
function mint(uint mintAmount) external returns (uint);
function redeem(uint redeemTokens) external returns (uint);
function redeemUnderlying(uint redeemAmount) external returns (uint);
function borrow(uint borrowAmount) external returns (uint);
function repayBorrow(uint repayAmount) external returns (uint);
function repayBorrowBehalf(address borrower, uint repayAmount) external returns (uint);
function liquidateBorrow(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) external returns (uint);
/*** Admin Functions ***/
function _addReserves(uint addAmount) external returns (uint);
} | /**
* @title Bird's BErc20 Interface
*/ | NatSpecMultiLine | _addReserves | function _addReserves(uint addAmount) external returns (uint);
| /*** Admin Functions ***/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
654,
720
]
} | 6,329 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BDelegatorInterface | contract BDelegatorInterface is BDelegationStorage {
/**
* @notice Emitted when implementation is changed
*/
event NewImplementation(address oldImplementation, address newImplementation);
/**
* @notice Called by the admin to update the implementation of the delegator
* @param implementation_ The address of the new implementation for delegation
* @param allowResign Flag to indicate whether to call _resignImplementation on the old implementation
* @param becomeImplementationData The encoded bytes data to be passed to _becomeImplementation
*/
function _setImplementation(address implementation_, bool allowResign, bytes memory becomeImplementationData) public;
} | /**
* @title Bird's BDelegator Interface
*/ | NatSpecMultiLine | _setImplementation | function _setImplementation(address implementation_, bool allowResign, bytes memory becomeImplementationData) public;
| /**
* @notice Called by the admin to update the implementation of the delegator
* @param implementation_ The address of the new implementation for delegation
* @param allowResign Flag to indicate whether to call _resignImplementation on the old implementation
* @param becomeImplementationData The encoded bytes data to be passed to _becomeImplementation
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
594,
715
]
} | 6,330 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BDelegateInterface | contract BDelegateInterface is BDelegationStorage {
/**
* @notice Called by the delegator on a delegate to initialize it for duty
* @dev Should revert if any issues arise which make it unfit for delegation
* @param data The encoded bytes data for any initialization
*/
function _becomeImplementation(bytes memory data) public;
/**
* @notice Called by the delegator on a delegate to forfeit its responsibility
*/
function _resignImplementation() public;
} | /**
* @title Bird's BDelegate Interface
*/ | NatSpecMultiLine | _becomeImplementation | function _becomeImplementation(bytes memory data) public;
| /**
* @notice Called by the delegator on a delegate to initialize it for duty
* @dev Should revert if any issues arise which make it unfit for delegation
* @param data The encoded bytes data for any initialization
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
293,
354
]
} | 6,331 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BDelegateInterface | contract BDelegateInterface is BDelegationStorage {
/**
* @notice Called by the delegator on a delegate to initialize it for duty
* @dev Should revert if any issues arise which make it unfit for delegation
* @param data The encoded bytes data for any initialization
*/
function _becomeImplementation(bytes memory data) public;
/**
* @notice Called by the delegator on a delegate to forfeit its responsibility
*/
function _resignImplementation() public;
} | /**
* @title Bird's BDelegate Interface
*/ | NatSpecMultiLine | _resignImplementation | function _resignImplementation() public;
| /**
* @notice Called by the delegator on a delegate to forfeit its responsibility
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
455,
499
]
} | 6,332 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BControllerErrorReporter | contract BControllerErrorReporter {
enum Error {
NO_ERROR,
UNAUTHORIZED,
BCONTROLLER_MISMATCH,
INSUFFICIENT_SHORTFALL,
INSUFFICIENT_LIQUIDITY,
INVALID_CLOSE_FACTOR,
INVALID_COLLATERAL_FACTOR,
INVALID_LIQUIDATION_INCENTIVE,
MARKET_NOT_ENTERED, // no longer possible
MARKET_NOT_LISTED,
MARKET_ALREADY_LISTED,
MATH_ERROR,
NONZERO_BORROW_BALANCE,
PRICE_ERROR,
REJECTION,
SNAPSHOT_ERROR,
TOO_MANY_ASSETS,
TOO_MUCH_REPAY
}
enum FailureInfo {
ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
ACCEPT_PENDING_IMPLEMENTATION_ADDRESS_CHECK,
EXIT_MARKET_BALANCE_OWED,
EXIT_MARKET_REJECTION,
SET_CLOSE_FACTOR_OWNER_CHECK,
SET_CLOSE_FACTOR_VALIDATION,
SET_COLLATERAL_FACTOR_OWNER_CHECK,
SET_COLLATERAL_FACTOR_NO_EXISTS,
SET_COLLATERAL_FACTOR_VALIDATION,
SET_COLLATERAL_FACTOR_WITHOUT_PRICE,
SET_IMPLEMENTATION_OWNER_CHECK,
SET_LIQUIDATION_INCENTIVE_OWNER_CHECK,
SET_LIQUIDATION_INCENTIVE_VALIDATION,
SET_MAX_ASSETS_OWNER_CHECK,
SET_PENDING_ADMIN_OWNER_CHECK,
SET_PENDING_IMPLEMENTATION_OWNER_CHECK,
SET_PRICE_ORACLE_OWNER_CHECK,
SUPPORT_MARKET_EXISTS,
SUPPORT_MARKET_OWNER_CHECK,
SET_PAUSE_GUARDIAN_OWNER_CHECK
}
/**
* @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary
* contract-specific code that enables us to report opaque error codes from upgradeable contracts.
**/
event Failure(uint error, uint info, uint detail);
/**
* @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
*/
function fail(Error err, FailureInfo info) internal returns (uint) {
emit Failure(uint(err), uint(info), 0);
return uint(err);
}
/**
* @dev use this when reporting an opaque error from an upgradeable collaborator contract
*/
function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
emit Failure(uint(err), uint(info), opaqueError);
return uint(err);
}
} | fail | function fail(Error err, FailureInfo info) internal returns (uint) {
emit Failure(uint(err), uint(info), 0);
return uint(err);
}
| /**
* @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1825,
1978
]
} | 6,333 |
||||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BControllerErrorReporter | contract BControllerErrorReporter {
enum Error {
NO_ERROR,
UNAUTHORIZED,
BCONTROLLER_MISMATCH,
INSUFFICIENT_SHORTFALL,
INSUFFICIENT_LIQUIDITY,
INVALID_CLOSE_FACTOR,
INVALID_COLLATERAL_FACTOR,
INVALID_LIQUIDATION_INCENTIVE,
MARKET_NOT_ENTERED, // no longer possible
MARKET_NOT_LISTED,
MARKET_ALREADY_LISTED,
MATH_ERROR,
NONZERO_BORROW_BALANCE,
PRICE_ERROR,
REJECTION,
SNAPSHOT_ERROR,
TOO_MANY_ASSETS,
TOO_MUCH_REPAY
}
enum FailureInfo {
ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
ACCEPT_PENDING_IMPLEMENTATION_ADDRESS_CHECK,
EXIT_MARKET_BALANCE_OWED,
EXIT_MARKET_REJECTION,
SET_CLOSE_FACTOR_OWNER_CHECK,
SET_CLOSE_FACTOR_VALIDATION,
SET_COLLATERAL_FACTOR_OWNER_CHECK,
SET_COLLATERAL_FACTOR_NO_EXISTS,
SET_COLLATERAL_FACTOR_VALIDATION,
SET_COLLATERAL_FACTOR_WITHOUT_PRICE,
SET_IMPLEMENTATION_OWNER_CHECK,
SET_LIQUIDATION_INCENTIVE_OWNER_CHECK,
SET_LIQUIDATION_INCENTIVE_VALIDATION,
SET_MAX_ASSETS_OWNER_CHECK,
SET_PENDING_ADMIN_OWNER_CHECK,
SET_PENDING_IMPLEMENTATION_OWNER_CHECK,
SET_PRICE_ORACLE_OWNER_CHECK,
SUPPORT_MARKET_EXISTS,
SUPPORT_MARKET_OWNER_CHECK,
SET_PAUSE_GUARDIAN_OWNER_CHECK
}
/**
* @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary
* contract-specific code that enables us to report opaque error codes from upgradeable contracts.
**/
event Failure(uint error, uint info, uint detail);
/**
* @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
*/
function fail(Error err, FailureInfo info) internal returns (uint) {
emit Failure(uint(err), uint(info), 0);
return uint(err);
}
/**
* @dev use this when reporting an opaque error from an upgradeable collaborator contract
*/
function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
emit Failure(uint(err), uint(info), opaqueError);
return uint(err);
}
} | failOpaque | function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
emit Failure(uint(err), uint(info), opaqueError);
return uint(err);
}
| /**
* @dev use this when reporting an opaque error from an upgradeable collaborator contract
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2092,
2279
]
} | 6,334 |
||||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | TokenErrorReporter | contract TokenErrorReporter {
enum Error {
NO_ERROR,
UNAUTHORIZED,
BAD_INPUT,
BCONTROLLER_REJECTION,
BCONTROLLER_CALCULATION_ERROR,
INTEREST_RATE_MODEL_ERROR,
INVALID_ACCOUNT_PAIR,
INVALID_CLOSE_AMOUNT_REQUESTED,
INVALID_COLLATERAL_FACTOR,
MATH_ERROR,
MARKET_NOT_FRESH,
MARKET_NOT_LISTED,
TOKEN_INSUFFICIENT_ALLOWANCE,
TOKEN_INSUFFICIENT_BALANCE,
TOKEN_INSUFFICIENT_CASH,
TOKEN_TRANSFER_IN_FAILED,
TOKEN_TRANSFER_OUT_FAILED
}
/*
* Note: FailureInfo (but not Error) is kept in alphabetical order
* This is because FailureInfo grows significantly faster, and
* the order of Error has some meaning, while the order of FailureInfo
* is entirely arbitrary.
*/
enum FailureInfo {
ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED,
ACCRUE_INTEREST_BORROW_RATE_CALCULATION_FAILED,
ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED,
ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED,
ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED,
ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED,
BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
BORROW_ACCRUE_INTEREST_FAILED,
BORROW_CASH_NOT_AVAILABLE,
BORROW_FRESHNESS_CHECK,
BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
BORROW_MARKET_NOT_LISTED,
BORROW_BCONTROLLER_REJECTION,
LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED,
LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED,
LIQUIDATE_COLLATERAL_FRESHNESS_CHECK,
LIQUIDATE_BCONTROLLER_REJECTION,
LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED,
LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX,
LIQUIDATE_CLOSE_AMOUNT_IS_ZERO,
LIQUIDATE_FRESHNESS_CHECK,
LIQUIDATE_LIQUIDATOR_IS_BORROWER,
LIQUIDATE_REPAY_BORROW_FRESH_FAILED,
LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED,
LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED,
LIQUIDATE_SEIZE_BCONTROLLER_REJECTION,
LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER,
LIQUIDATE_SEIZE_TOO_MUCH,
MINT_ACCRUE_INTEREST_FAILED,
MINT_BCONTROLLER_REJECTION,
MINT_EXCHANGE_CALCULATION_FAILED,
MINT_EXCHANGE_RATE_READ_FAILED,
MINT_FRESHNESS_CHECK,
MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
MINT_TRANSFER_IN_FAILED,
MINT_TRANSFER_IN_NOT_POSSIBLE,
REDEEM_ACCRUE_INTEREST_FAILED,
REDEEM_BCONTROLLER_REJECTION,
REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED,
REDEEM_EXCHANGE_RATE_READ_FAILED,
REDEEM_FRESHNESS_CHECK,
REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
REDEEM_TRANSFER_OUT_NOT_POSSIBLE,
REDUCE_RESERVES_ACCRUE_INTEREST_FAILED,
REDUCE_RESERVES_ADMIN_CHECK,
REDUCE_RESERVES_CASH_NOT_AVAILABLE,
REDUCE_RESERVES_FRESH_CHECK,
REDUCE_RESERVES_VALIDATION,
REPAY_BEHALF_ACCRUE_INTEREST_FAILED,
REPAY_BORROW_ACCRUE_INTEREST_FAILED,
REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
REPAY_BORROW_BCONTROLLER_REJECTION,
REPAY_BORROW_FRESHNESS_CHECK,
REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
REPAY_BORROW_TRANSFER_IN_NOT_POSSIBLE,
SET_COLLATERAL_FACTOR_OWNER_CHECK,
SET_COLLATERAL_FACTOR_VALIDATION,
SET_BCONTROLLER_OWNER_CHECK,
SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED,
SET_INTEREST_RATE_MODEL_FRESH_CHECK,
SET_INTEREST_RATE_MODEL_OWNER_CHECK,
SET_MAX_ASSETS_OWNER_CHECK,
SET_ORACLE_MARKET_NOT_LISTED,
SET_PENDING_ADMIN_OWNER_CHECK,
SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED,
SET_RESERVE_FACTOR_ADMIN_CHECK,
SET_RESERVE_FACTOR_FRESH_CHECK,
SET_RESERVE_FACTOR_BOUNDS_CHECK,
TRANSFER_BCONTROLLER_REJECTION,
TRANSFER_NOT_ALLOWED,
TRANSFER_NOT_ENOUGH,
TRANSFER_TOO_MUCH,
ADD_RESERVES_ACCRUE_INTEREST_FAILED,
ADD_RESERVES_FRESH_CHECK,
ADD_RESERVES_TRANSFER_IN_NOT_POSSIBLE
}
/**
* @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary
* contract-specific code that enables us to report opaque error codes from upgradeable contracts.
**/
event Failure(uint error, uint info, uint detail);
/**
* @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
*/
function fail(Error err, FailureInfo info) internal returns (uint) {
emit Failure(uint(err), uint(info), 0);
return uint(err);
}
/**
* @dev use this when reporting an opaque error from an upgradeable collaborator contract
*/
function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
emit Failure(uint(err), uint(info), opaqueError);
return uint(err);
}
} | fail | function fail(Error err, FailureInfo info) internal returns (uint) {
emit Failure(uint(err), uint(info), 0);
return uint(err);
}
| /**
* @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
4920,
5073
]
} | 6,335 |
||||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | TokenErrorReporter | contract TokenErrorReporter {
enum Error {
NO_ERROR,
UNAUTHORIZED,
BAD_INPUT,
BCONTROLLER_REJECTION,
BCONTROLLER_CALCULATION_ERROR,
INTEREST_RATE_MODEL_ERROR,
INVALID_ACCOUNT_PAIR,
INVALID_CLOSE_AMOUNT_REQUESTED,
INVALID_COLLATERAL_FACTOR,
MATH_ERROR,
MARKET_NOT_FRESH,
MARKET_NOT_LISTED,
TOKEN_INSUFFICIENT_ALLOWANCE,
TOKEN_INSUFFICIENT_BALANCE,
TOKEN_INSUFFICIENT_CASH,
TOKEN_TRANSFER_IN_FAILED,
TOKEN_TRANSFER_OUT_FAILED
}
/*
* Note: FailureInfo (but not Error) is kept in alphabetical order
* This is because FailureInfo grows significantly faster, and
* the order of Error has some meaning, while the order of FailureInfo
* is entirely arbitrary.
*/
enum FailureInfo {
ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED,
ACCRUE_INTEREST_BORROW_RATE_CALCULATION_FAILED,
ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED,
ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED,
ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED,
ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED,
BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
BORROW_ACCRUE_INTEREST_FAILED,
BORROW_CASH_NOT_AVAILABLE,
BORROW_FRESHNESS_CHECK,
BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
BORROW_MARKET_NOT_LISTED,
BORROW_BCONTROLLER_REJECTION,
LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED,
LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED,
LIQUIDATE_COLLATERAL_FRESHNESS_CHECK,
LIQUIDATE_BCONTROLLER_REJECTION,
LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED,
LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX,
LIQUIDATE_CLOSE_AMOUNT_IS_ZERO,
LIQUIDATE_FRESHNESS_CHECK,
LIQUIDATE_LIQUIDATOR_IS_BORROWER,
LIQUIDATE_REPAY_BORROW_FRESH_FAILED,
LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED,
LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED,
LIQUIDATE_SEIZE_BCONTROLLER_REJECTION,
LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER,
LIQUIDATE_SEIZE_TOO_MUCH,
MINT_ACCRUE_INTEREST_FAILED,
MINT_BCONTROLLER_REJECTION,
MINT_EXCHANGE_CALCULATION_FAILED,
MINT_EXCHANGE_RATE_READ_FAILED,
MINT_FRESHNESS_CHECK,
MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
MINT_TRANSFER_IN_FAILED,
MINT_TRANSFER_IN_NOT_POSSIBLE,
REDEEM_ACCRUE_INTEREST_FAILED,
REDEEM_BCONTROLLER_REJECTION,
REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED,
REDEEM_EXCHANGE_RATE_READ_FAILED,
REDEEM_FRESHNESS_CHECK,
REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
REDEEM_TRANSFER_OUT_NOT_POSSIBLE,
REDUCE_RESERVES_ACCRUE_INTEREST_FAILED,
REDUCE_RESERVES_ADMIN_CHECK,
REDUCE_RESERVES_CASH_NOT_AVAILABLE,
REDUCE_RESERVES_FRESH_CHECK,
REDUCE_RESERVES_VALIDATION,
REPAY_BEHALF_ACCRUE_INTEREST_FAILED,
REPAY_BORROW_ACCRUE_INTEREST_FAILED,
REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
REPAY_BORROW_BCONTROLLER_REJECTION,
REPAY_BORROW_FRESHNESS_CHECK,
REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
REPAY_BORROW_TRANSFER_IN_NOT_POSSIBLE,
SET_COLLATERAL_FACTOR_OWNER_CHECK,
SET_COLLATERAL_FACTOR_VALIDATION,
SET_BCONTROLLER_OWNER_CHECK,
SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED,
SET_INTEREST_RATE_MODEL_FRESH_CHECK,
SET_INTEREST_RATE_MODEL_OWNER_CHECK,
SET_MAX_ASSETS_OWNER_CHECK,
SET_ORACLE_MARKET_NOT_LISTED,
SET_PENDING_ADMIN_OWNER_CHECK,
SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED,
SET_RESERVE_FACTOR_ADMIN_CHECK,
SET_RESERVE_FACTOR_FRESH_CHECK,
SET_RESERVE_FACTOR_BOUNDS_CHECK,
TRANSFER_BCONTROLLER_REJECTION,
TRANSFER_NOT_ALLOWED,
TRANSFER_NOT_ENOUGH,
TRANSFER_TOO_MUCH,
ADD_RESERVES_ACCRUE_INTEREST_FAILED,
ADD_RESERVES_FRESH_CHECK,
ADD_RESERVES_TRANSFER_IN_NOT_POSSIBLE
}
/**
* @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary
* contract-specific code that enables us to report opaque error codes from upgradeable contracts.
**/
event Failure(uint error, uint info, uint detail);
/**
* @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
*/
function fail(Error err, FailureInfo info) internal returns (uint) {
emit Failure(uint(err), uint(info), 0);
return uint(err);
}
/**
* @dev use this when reporting an opaque error from an upgradeable collaborator contract
*/
function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
emit Failure(uint(err), uint(info), opaqueError);
return uint(err);
}
} | failOpaque | function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
emit Failure(uint(err), uint(info), opaqueError);
return uint(err);
}
| /**
* @dev use this when reporting an opaque error from an upgradeable collaborator contract
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
5187,
5374
]
} | 6,336 |
||||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | CarefulMath | contract CarefulMath {
/**
* @dev Possible error codes that we can return
*/
enum MathError {
NO_ERROR,
DIVISION_BY_ZERO,
INTEGER_OVERFLOW,
INTEGER_UNDERFLOW
}
/**
* @dev Multiplies two numbers, returns an error on overflow.
*/
function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (a == 0) {
return (MathError.NO_ERROR, 0);
}
uint c = a * b;
if (c / a != b) {
return (MathError.INTEGER_OVERFLOW, 0);
} else {
return (MathError.NO_ERROR, c);
}
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b == 0) {
return (MathError.DIVISION_BY_ZERO, 0);
}
return (MathError.NO_ERROR, a / b);
}
/**
* @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
*/
function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b <= a) {
return (MathError.NO_ERROR, a - b);
} else {
return (MathError.INTEGER_UNDERFLOW, 0);
}
}
/**
* @dev Adds two numbers, returns an error on overflow.
*/
function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
uint c = a + b;
if (c >= a) {
return (MathError.NO_ERROR, c);
} else {
return (MathError.INTEGER_OVERFLOW, 0);
}
}
/**
* @dev add a and b and then subtract c
*/
function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
(MathError err0, uint sum) = addUInt(a, b);
if (err0 != MathError.NO_ERROR) {
return (err0, 0);
}
return subUInt(sum, c);
}
} | /**
* @title Careful Math
* @notice Derived from OpenZeppelin's SafeMath library
* https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
*/ | NatSpecMultiLine | mulUInt | function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (a == 0) {
return (MathError.NO_ERROR, 0);
}
uint c = a * b;
if (c / a != b) {
return (MathError.INTEGER_OVERFLOW, 0);
} else {
return (MathError.NO_ERROR, c);
}
}
| /**
* @dev Multiplies two numbers, returns an error on overflow.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
296,
631
]
} | 6,337 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | CarefulMath | contract CarefulMath {
/**
* @dev Possible error codes that we can return
*/
enum MathError {
NO_ERROR,
DIVISION_BY_ZERO,
INTEGER_OVERFLOW,
INTEGER_UNDERFLOW
}
/**
* @dev Multiplies two numbers, returns an error on overflow.
*/
function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (a == 0) {
return (MathError.NO_ERROR, 0);
}
uint c = a * b;
if (c / a != b) {
return (MathError.INTEGER_OVERFLOW, 0);
} else {
return (MathError.NO_ERROR, c);
}
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b == 0) {
return (MathError.DIVISION_BY_ZERO, 0);
}
return (MathError.NO_ERROR, a / b);
}
/**
* @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
*/
function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b <= a) {
return (MathError.NO_ERROR, a - b);
} else {
return (MathError.INTEGER_UNDERFLOW, 0);
}
}
/**
* @dev Adds two numbers, returns an error on overflow.
*/
function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
uint c = a + b;
if (c >= a) {
return (MathError.NO_ERROR, c);
} else {
return (MathError.INTEGER_OVERFLOW, 0);
}
}
/**
* @dev add a and b and then subtract c
*/
function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
(MathError err0, uint sum) = addUInt(a, b);
if (err0 != MathError.NO_ERROR) {
return (err0, 0);
}
return subUInt(sum, c);
}
} | /**
* @title Careful Math
* @notice Derived from OpenZeppelin's SafeMath library
* https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
*/ | NatSpecMultiLine | divUInt | function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b == 0) {
return (MathError.DIVISION_BY_ZERO, 0);
}
return (MathError.NO_ERROR, a / b);
}
| /**
* @dev Integer division of two numbers, truncating the quotient.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
717,
930
]
} | 6,338 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | CarefulMath | contract CarefulMath {
/**
* @dev Possible error codes that we can return
*/
enum MathError {
NO_ERROR,
DIVISION_BY_ZERO,
INTEGER_OVERFLOW,
INTEGER_UNDERFLOW
}
/**
* @dev Multiplies two numbers, returns an error on overflow.
*/
function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (a == 0) {
return (MathError.NO_ERROR, 0);
}
uint c = a * b;
if (c / a != b) {
return (MathError.INTEGER_OVERFLOW, 0);
} else {
return (MathError.NO_ERROR, c);
}
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b == 0) {
return (MathError.DIVISION_BY_ZERO, 0);
}
return (MathError.NO_ERROR, a / b);
}
/**
* @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
*/
function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b <= a) {
return (MathError.NO_ERROR, a - b);
} else {
return (MathError.INTEGER_UNDERFLOW, 0);
}
}
/**
* @dev Adds two numbers, returns an error on overflow.
*/
function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
uint c = a + b;
if (c >= a) {
return (MathError.NO_ERROR, c);
} else {
return (MathError.INTEGER_OVERFLOW, 0);
}
}
/**
* @dev add a and b and then subtract c
*/
function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
(MathError err0, uint sum) = addUInt(a, b);
if (err0 != MathError.NO_ERROR) {
return (err0, 0);
}
return subUInt(sum, c);
}
} | /**
* @title Careful Math
* @notice Derived from OpenZeppelin's SafeMath library
* https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
*/ | NatSpecMultiLine | subUInt | function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b <= a) {
return (MathError.NO_ERROR, a - b);
} else {
return (MathError.INTEGER_UNDERFLOW, 0);
}
}
| /**
* @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1056,
1290
]
} | 6,339 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | CarefulMath | contract CarefulMath {
/**
* @dev Possible error codes that we can return
*/
enum MathError {
NO_ERROR,
DIVISION_BY_ZERO,
INTEGER_OVERFLOW,
INTEGER_UNDERFLOW
}
/**
* @dev Multiplies two numbers, returns an error on overflow.
*/
function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (a == 0) {
return (MathError.NO_ERROR, 0);
}
uint c = a * b;
if (c / a != b) {
return (MathError.INTEGER_OVERFLOW, 0);
} else {
return (MathError.NO_ERROR, c);
}
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b == 0) {
return (MathError.DIVISION_BY_ZERO, 0);
}
return (MathError.NO_ERROR, a / b);
}
/**
* @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
*/
function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b <= a) {
return (MathError.NO_ERROR, a - b);
} else {
return (MathError.INTEGER_UNDERFLOW, 0);
}
}
/**
* @dev Adds two numbers, returns an error on overflow.
*/
function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
uint c = a + b;
if (c >= a) {
return (MathError.NO_ERROR, c);
} else {
return (MathError.INTEGER_OVERFLOW, 0);
}
}
/**
* @dev add a and b and then subtract c
*/
function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
(MathError err0, uint sum) = addUInt(a, b);
if (err0 != MathError.NO_ERROR) {
return (err0, 0);
}
return subUInt(sum, c);
}
} | /**
* @title Careful Math
* @notice Derived from OpenZeppelin's SafeMath library
* https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
*/ | NatSpecMultiLine | addUInt | function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
uint c = a + b;
if (c >= a) {
return (MathError.NO_ERROR, c);
} else {
return (MathError.INTEGER_OVERFLOW, 0);
}
}
| /**
* @dev Adds two numbers, returns an error on overflow.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1366,
1620
]
} | 6,340 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | CarefulMath | contract CarefulMath {
/**
* @dev Possible error codes that we can return
*/
enum MathError {
NO_ERROR,
DIVISION_BY_ZERO,
INTEGER_OVERFLOW,
INTEGER_UNDERFLOW
}
/**
* @dev Multiplies two numbers, returns an error on overflow.
*/
function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (a == 0) {
return (MathError.NO_ERROR, 0);
}
uint c = a * b;
if (c / a != b) {
return (MathError.INTEGER_OVERFLOW, 0);
} else {
return (MathError.NO_ERROR, c);
}
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b == 0) {
return (MathError.DIVISION_BY_ZERO, 0);
}
return (MathError.NO_ERROR, a / b);
}
/**
* @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
*/
function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
if (b <= a) {
return (MathError.NO_ERROR, a - b);
} else {
return (MathError.INTEGER_UNDERFLOW, 0);
}
}
/**
* @dev Adds two numbers, returns an error on overflow.
*/
function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
uint c = a + b;
if (c >= a) {
return (MathError.NO_ERROR, c);
} else {
return (MathError.INTEGER_OVERFLOW, 0);
}
}
/**
* @dev add a and b and then subtract c
*/
function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
(MathError err0, uint sum) = addUInt(a, b);
if (err0 != MathError.NO_ERROR) {
return (err0, 0);
}
return subUInt(sum, c);
}
} | /**
* @title Careful Math
* @notice Derived from OpenZeppelin's SafeMath library
* https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
*/ | NatSpecMultiLine | addThenSubUInt | function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
(MathError err0, uint sum) = addUInt(a, b);
if (err0 != MathError.NO_ERROR) {
return (err0, 0);
}
return subUInt(sum, c);
}
| /**
* @dev add a and b and then subtract c
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1680,
1947
]
} | 6,341 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | getExp | function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
| /**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
492,
999
]
} | 6,342 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | addExp | function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
| /**
* @dev Adds two exponentials, returning a new exponential.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1081,
1306
]
} | 6,343 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | subExp | function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
| /**
* @dev Subtracts two exponentials, returning a new exponential.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1393,
1618
]
} | 6,344 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | mulScalar | function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
| /**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1698,
2048
]
} | 6,345 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | mulScalarTruncate | function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
| /**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2152,
2462
]
} | 6,346 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | mulScalarTruncateAddUInt | function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
| /**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2598,
2923
]
} | 6,347 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | divScalar | function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
| /**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
3001,
3355
]
} | 6,348 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | divScalarByExp | function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
| /**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
3433,
4042
]
} | 6,349 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | divScalarByExpTruncate | function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
| /**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
4144,
4478
]
} | 6,350 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | mulExp | function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
| /**
* @dev Multiplies two exponentials, returning a new exponential.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
4566,
5686
]
} | 6,351 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | mulExp | function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
| /**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
5796,
5948
]
} | 6,352 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | mulExp3 | function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
| /**
* @dev Multiplies three exponentials, returning a new exponential.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
6038,
6320
]
} | 6,353 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | divExp | function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
| /**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
6548,
6696
]
} | 6,354 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | truncate | function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
| /**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
6844,
7058
]
} | 6,355 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | lessThanExp | function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
| /**
* @dev Checks if first Exp is less than second Exp.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
7133,
7276
]
} | 6,356 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | lessThanOrEqualExp | function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
| /**
* @dev Checks if left Exp <= right Exp.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
7339,
7490
]
} | 6,357 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | greaterThanExp | function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
| /**
* @dev Checks if left Exp > right Exp.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
7552,
7698
]
} | 6,358 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | Exponential | contract Exponential is CarefulMath {
uint constant expScale = 1e18;
uint constant doubleScale = 1e36;
uint constant halfExpScale = expScale/2;
uint constant mantissaOne = expScale;
struct Exp {
uint mantissa;
}
struct Double {
uint mantissa;
}
/**
* @dev Creates an exponential from numerator and denominator values.
* Note: Returns an error if (`num` * 10e18) > MAX_INT,
* or if `denom` is zero.
*/
function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
(MathError err1, uint rational) = divUInt(scaledNumerator, denom);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: rational}));
}
/**
* @dev Adds two exponentials, returning a new exponential.
*/
function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = addUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Subtracts two exponentials, returning a new exponential.
*/
function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError error, uint result) = subUInt(a.mantissa, b.mantissa);
return (error, Exp({mantissa: result}));
}
/**
* @dev Multiply an Exp by a scalar, returning a new Exp.
*/
function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(product));
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
(MathError err, Exp memory product) = mulScalar(a, scalar);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return addUInt(truncate(product), addend);
}
/**
* @dev Divide an Exp by a scalar, returning a new Exp.
*/
function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
(MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
}
/**
* @dev Divide a scalar by an Exp, returning a new Exp.
*/
function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
/*
We are doing this as:
getExp(mulUInt(expScale, scalar), divisor.mantissa)
How it works:
Exp = a / b;
Scalar = s;
`s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
*/
(MathError err0, uint numerator) = mulUInt(expScale, scalar);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
return getExp(numerator, divisor.mantissa);
}
/**
* @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
*/
function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
(MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
if (err != MathError.NO_ERROR) {
return (err, 0);
}
return (MathError.NO_ERROR, truncate(fraction));
}
/**
* @dev Multiplies two exponentials, returning a new exponential.
*/
function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
(MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
if (err0 != MathError.NO_ERROR) {
return (err0, Exp({mantissa: 0}));
}
// We add half the scale before dividing so that we get rounding instead of truncation.
// See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
// Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
(MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
if (err1 != MathError.NO_ERROR) {
return (err1, Exp({mantissa: 0}));
}
(MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
// The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
assert(err2 == MathError.NO_ERROR);
return (MathError.NO_ERROR, Exp({mantissa: product}));
}
/**
* @dev Multiplies two exponentials given their mantissas, returning a new exponential.
*/
function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
}
/**
* @dev Multiplies three exponentials, returning a new exponential.
*/
function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
(MathError err, Exp memory ab) = mulExp(a, b);
if (err != MathError.NO_ERROR) {
return (err, ab);
}
return mulExp(ab, c);
}
/**
* @dev Divides two exponentials, returning a new exponential.
* (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
* which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
*/
function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
/**
* @dev Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) pure internal returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
function safe224(uint n, string memory errorMessage) pure internal returns (uint224) {
require(n < 2**224, errorMessage);
return uint224(n);
}
function safe32(uint n, string memory errorMessage) pure internal returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) pure internal returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) pure internal returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) pure internal returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) pure internal returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
if (a == 0 || b == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, errorMessage);
return c;
}
function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) pure internal returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(Double memory a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) pure internal returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) pure internal returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) pure internal returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
} | /**
* @title Exponential module for storing fixed-precision decimals
* @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
* Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
* `Exp({mantissa: 5100000000000000000})`.
*/ | NatSpecMultiLine | isZeroExp | function isZeroExp(Exp memory value) pure internal returns (bool) {
return value.mantissa == 0;
}
| /**
* @dev returns true if Exp is exactly zero
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
7764,
7877
]
} | 6,359 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20Interface | interface EIP20Interface {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external returns (bool success);
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title ERC 20 Token Standard Interface
* https://eips.ethereum.org/EIPS/eip-20
*/ | NatSpecMultiLine | totalSupply | function totalSupply() external view returns (uint256);
| /**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
319,
378
]
} | 6,360 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20Interface | interface EIP20Interface {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external returns (bool success);
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title ERC 20 Token Standard Interface
* https://eips.ethereum.org/EIPS/eip-20
*/ | NatSpecMultiLine | balanceOf | function balanceOf(address owner) external view returns (uint256 balance);
| /**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
553,
631
]
} | 6,361 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20Interface | interface EIP20Interface {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external returns (bool success);
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title ERC 20 Token Standard Interface
* https://eips.ethereum.org/EIPS/eip-20
*/ | NatSpecMultiLine | transfer | function transfer(address dst, uint256 amount) external returns (bool success);
| /**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
885,
968
]
} | 6,362 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20Interface | interface EIP20Interface {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external returns (bool success);
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title ERC 20 Token Standard Interface
* https://eips.ethereum.org/EIPS/eip-20
*/ | NatSpecMultiLine | transferFrom | function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
| /**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1268,
1368
]
} | 6,363 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20Interface | interface EIP20Interface {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external returns (bool success);
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title ERC 20 Token Standard Interface
* https://eips.ethereum.org/EIPS/eip-20
*/ | NatSpecMultiLine | approve | function approve(address spender, uint256 amount) external returns (bool success);
| /**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1831,
1917
]
} | 6,364 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20Interface | interface EIP20Interface {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external returns (bool success);
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external returns (bool success);
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title ERC 20 Token Standard Interface
* https://eips.ethereum.org/EIPS/eip-20
*/ | NatSpecMultiLine | allowance | function allowance(address owner, address spender) external view returns (uint256 remaining);
| /**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2240,
2337
]
} | 6,365 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20NonStandardInterface | interface EIP20NonStandardInterface {
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transfer(address dst, uint256 amount) external;
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transferFrom(address src, address dst, uint256 amount) external;
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title EIP20NonStandardInterface
* @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
* See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/ | NatSpecMultiLine | totalSupply | function totalSupply() external view returns (uint256);
| /**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
152,
211
]
} | 6,366 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20NonStandardInterface | interface EIP20NonStandardInterface {
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transfer(address dst, uint256 amount) external;
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transferFrom(address src, address dst, uint256 amount) external;
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title EIP20NonStandardInterface
* @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
* See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/ | NatSpecMultiLine | balanceOf | function balanceOf(address owner) external view returns (uint256 balance);
| /**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
386,
464
]
} | 6,367 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20NonStandardInterface | interface EIP20NonStandardInterface {
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transfer(address dst, uint256 amount) external;
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transferFrom(address src, address dst, uint256 amount) external;
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title EIP20NonStandardInterface
* @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
* See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/ | NatSpecMultiLine | transfer | function transfer(address dst, uint256 amount) external;
| /**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
827,
887
]
} | 6,368 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20NonStandardInterface | interface EIP20NonStandardInterface {
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transfer(address dst, uint256 amount) external;
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transferFrom(address src, address dst, uint256 amount) external;
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title EIP20NonStandardInterface
* @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
* See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/ | NatSpecMultiLine | transferFrom | function transferFrom(address src, address dst, uint256 amount) external;
| /**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1300,
1377
]
} | 6,369 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20NonStandardInterface | interface EIP20NonStandardInterface {
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transfer(address dst, uint256 amount) external;
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transferFrom(address src, address dst, uint256 amount) external;
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title EIP20NonStandardInterface
* @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
* See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/ | NatSpecMultiLine | approve | function approve(address spender, uint256 amount) external returns (bool success);
| /**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
1820,
1906
]
} | 6,370 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | EIP20NonStandardInterface | interface EIP20NonStandardInterface {
/**
* @notice Get the total number of tokens in circulation
* @return The supply of tokens
*/
function totalSupply() external view returns (uint256);
/**
* @notice Gets the balance of the specified address
* @param owner The address from which the balance will be retrieved
* @return The balance
*/
function balanceOf(address owner) external view returns (uint256 balance);
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transfer(address dst, uint256 amount) external;
///
/// !!!!!!!!!!!!!!
/// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
/// !!!!!!!!!!!!!!
///
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
*/
function transferFrom(address src, address dst, uint256 amount) external;
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool success);
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/
function allowance(address owner, address spender) external view returns (uint256 remaining);
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
} | /**
* @title EIP20NonStandardInterface
* @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
* See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/ | NatSpecMultiLine | allowance | function allowance(address owner, address spender) external view returns (uint256 remaining);
| /**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2209,
2306
]
} | 6,371 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | initialize | function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
| /**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
504,
2006
]
} | 6,372 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | transferTokens | function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
| /**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
2454,
4615
]
} | 6,373 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | transfer | function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
| /**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
4864,
5051
]
} | 6,374 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | transferFrom | function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
| /**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
5345,
5542
]
} | 6,375 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | approve | function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
| /**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
5998,
6234
]
} | 6,376 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | allowance | function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
| /**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
6552,
6697
]
} | 6,377 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | balanceOf | function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
| /**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
6876,
6990
]
} | 6,378 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | balanceOfUnderlying | function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
| /**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
7234,
7587
]
} | 6,379 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | getAccountSnapshot | function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
| /**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
7921,
8610
]
} | 6,380 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | getBlockNumber | function getBlockNumber() internal view returns (uint) {
return block.number;
}
| /**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
8759,
8854
]
} | 6,381 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | borrowRatePerBlock | function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
| /**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
9020,
9183
]
} | 6,382 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | supplyRatePerBlock | function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
| /**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
9349,
9535
]
} | 6,383 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | totalBorrowsCurrent | function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
| /**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
9671,
9864
]
} | 6,384 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | borrowBalanceCurrent | function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
| /**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
10144,
10369
]
} | 6,385 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | borrowBalanceStored | function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
| /**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
10567,
10854
]
} | 6,386 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | borrowBalanceStoredInternal | function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
| /**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
11097,
12339
]
} | 6,387 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | exchangeRateCurrent | function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
| /**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
12484,
12683
]
} | 6,388 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | exchangeRateStored | function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
| /**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
12922,
13183
]
} | 6,389 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | exchangeRateStoredInternal | function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
| /**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
13436,
14596
]
} | 6,390 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | getCash | function getCash() external view returns (uint) {
return getCashPrior();
}
| /**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
14756,
14846
]
} | 6,391 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | accrueInterest | function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
| /**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
15083,
18866
]
} | 6,392 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | mintInternal | function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
| /**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
19252,
19795
]
} | 6,393 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | mintFresh | function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
| /**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
20482,
23604
]
} | 6,394 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | redeemInternal | function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
| /**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
23943,
24466
]
} | 6,395 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | redeemUnderlyingInternal | function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
| /**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
24834,
25367
]
} | 6,396 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | redeemFresh | function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
| /**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
26232,
30746
]
} | 6,397 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | borrowInternal | function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
| /**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
31003,
31523
]
} | 6,398 |
||
SimplePriceOracle | SimplePriceOracle.sol | 0x624128c9f71dc9ca6876f2f75d6e8f64899209d7 | Solidity | BToken | contract BToken is BTokenInterface, Exponential, TokenErrorReporter {
/**
* @notice Initialize the money market
* @param bController_ The address of the BController
* @param interestRateModel_ The address of the interest rate model
* @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
* @param name_ EIP-20 name of this token
* @param symbol_ EIP-20 symbol of this token
* @param decimals_ EIP-20 decimal precision of this token
*/
function initialize(BControllerInterface bController_,
InterestRateModel interestRateModel_,
uint initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_) public {
require(msg.sender == admin, "only admin may initialize the market");
require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once");
// Set initial exchange rate
initialExchangeRateMantissa = initialExchangeRateMantissa_;
require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero.");
// Set the bController
uint err = _setBController(bController_);
require(err == uint(Error.NO_ERROR), "setting bController failed");
// Initialize block number and borrow index (block number mocks depend on bController being set)
accrualBlockNumber = getBlockNumber();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block number / borrow index)
err = _setInterestRateModelFresh(interestRateModel_);
require(err == uint(Error.NO_ERROR), "setting interest rate model failed");
name = name_;
symbol = symbol_;
decimals = decimals_;
// The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
_notEntered = true;
}
/**
* @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
* @dev Called by both `transfer` and `transferFrom` internally
* @param spender The address of the account performing the transfer
* @param src The address of the source account
* @param dst The address of the destination account
* @param tokens The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
/* Fail if transfer not allowed */
uint allowed = bController.transferAllowed(address(this), src, dst, tokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.TRANSFER_BCONTROLLER_REJECTION, allowed);
}
/* Do not allow self-transfers */
if (src == dst) {
return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
}
/* Get the allowance, infinite for the account owner */
uint startingAllowance = 0;
if (spender == src) {
startingAllowance = uint(-1);
} else {
startingAllowance = transferAllowances[src][spender];
}
/* Do the calculations, checking for {under,over}flow */
MathError mathErr;
uint allowanceNew;
uint scrTokensNew;
uint dstTokensNew;
(mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
}
(mathErr, scrTokensNew) = subUInt(accountTokens[src], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
}
(mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
if (mathErr != MathError.NO_ERROR) {
return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
accountTokens[src] = scrTokensNew;
accountTokens[dst] = dstTokensNew;
/* Eat some of the allowance (if necessary) */
if (startingAllowance != uint(-1)) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
bController.transferVerify(address(this), src, dst, tokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `msg.sender` to `dst`
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Transfer `amount` tokens from `src` to `dst`
* @param src The address of the source account
* @param dst The address of the destination account
* @param amount The number of tokens to transfer
* @return Whether or not the transfer succeeded
*/
function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
}
/**
* @notice Approve `spender` to transfer up to `amount` from `src`
* @dev This will overwrite the approval amount for `spender`
* and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
* @param spender The address of the account which may transfer tokens
* @param amount The number of tokens that are approved (-1 means infinite)
* @return Whether or not the approval succeeded
*/
function approve(address spender, uint256 amount) external returns (bool) {
address src = msg.sender;
transferAllowances[src][spender] = amount;
emit Approval(src, spender, amount);
return true;
}
/**
* @notice Get the current allowance from `owner` for `spender`
* @param owner The address of the account which owns the tokens to be spent
* @param spender The address of the account which may transfer tokens
* @return The number of tokens allowed to be spent (-1 means infinite)
*/
function allowance(address owner, address spender) external view returns (uint256) {
return transferAllowances[owner][spender];
}
/**
* @notice Get the token balance of the `owner`
* @param owner The address of the account to query
* @return The number of tokens owned by `owner`
*/
function balanceOf(address owner) external view returns (uint256) {
return accountTokens[owner];
}
/**
* @notice Get the underlying balance of the `owner`
* @dev This also accrues interest in a transaction
* @param owner The address of the account to query
* @return The amount of underlying owned by `owner`
*/
function balanceOfUnderlying(address owner) external returns (uint) {
Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
(MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
require(mErr == MathError.NO_ERROR, "balance could not be calculated");
return balance;
}
/**
* @notice Get a snapshot of the account's balances, and the cached exchange rate
* @dev This is used by bController to more efficiently perform liquidity checks.
* @param account Address of the account to snapshot
* @return (possible error, token balance, borrow balance, exchange rate mantissa)
*/
function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
uint bTokenBalance = accountTokens[account];
uint borrowBalance;
uint exchangeRateMantissa;
MathError mErr;
(mErr, borrowBalance) = borrowBalanceStoredInternal(account);
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
(mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
if (mErr != MathError.NO_ERROR) {
return (uint(Error.MATH_ERROR), 0, 0, 0);
}
return (uint(Error.NO_ERROR), bTokenBalance, borrowBalance, exchangeRateMantissa);
}
/**
* @dev Function to simply retrieve block number
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockNumber() internal view returns (uint) {
return block.number;
}
/**
* @notice Returns the current per-block borrow interest rate for this bToken
* @return The borrow interest rate per block, scaled by 1e18
*/
function borrowRatePerBlock() external view returns (uint) {
return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
}
/**
* @notice Returns the current per-block supply interest rate for this bToken
* @return The supply interest rate per block, scaled by 1e18
*/
function supplyRatePerBlock() external view returns (uint) {
return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa);
}
/**
* @notice Returns the current total borrows plus accrued interest
* @return The total borrows with interest
*/
function totalBorrowsCurrent() external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return totalBorrows;
}
/**
* @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
* @param account The address whose balance should be calculated after updating borrowIndex
* @return The calculated balance
*/
function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return borrowBalanceStored(account);
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return The calculated balance
*/
function borrowBalanceStored(address account) public view returns (uint) {
(MathError err, uint result) = borrowBalanceStoredInternal(account);
require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
return result;
}
/**
* @notice Return the borrow balance of account based on stored data
* @param account The address whose balance should be calculated
* @return (error code, the calculated balance or 0 if error code is non-zero)
*/
function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
/* Note: we do not assert that the market is up to date */
MathError mathErr;
uint principalTimesIndex;
uint result;
/* Get borrowBalance and borrowIndex */
BorrowSnapshot storage borrowSnapshot = accountBorrows[account];
/* If borrowBalance = 0 then borrowIndex is likely also 0.
* Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
*/
if (borrowSnapshot.principal == 0) {
return (MathError.NO_ERROR, 0);
}
/* Calculate new borrow balance using the interest index:
* recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
*/
(mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, result);
}
/**
* @notice Accrue interest then return the up-to-date exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateCurrent() public nonReentrant returns (uint) {
require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view returns (uint) {
(MathError err, uint result) = exchangeRateStoredInternal();
require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
return result;
}
/**
* @notice Calculates the exchange rate from the underlying to the BToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return (error code, calculated exchange rate scaled by 1e18)
*/
function exchangeRateStoredInternal() internal view returns (MathError, uint) {
uint _totalSupply = totalSupply;
if (_totalSupply == 0) {
/*
* If there are no tokens minted:
* exchangeRate = initialExchangeRate
*/
return (MathError.NO_ERROR, initialExchangeRateMantissa);
} else {
/*
* Otherwise:
* exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
*/
uint totalCash = getCashPrior();
uint cashPlusBorrowsMinusReserves;
Exp memory exchangeRate;
MathError mathErr;
(mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
(mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply);
if (mathErr != MathError.NO_ERROR) {
return (mathErr, 0);
}
return (MathError.NO_ERROR, exchangeRate.mantissa);
}
}
/**
* @notice Get cash balance of this bToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view returns (uint) {
return getCashPrior();
}
/**
* @notice Applies accrued interest to total borrows and reserves
* @dev This calculates interest accrued from the last checkpointed block
* up to the current block and writes new checkpoint to storage.
*/
function accrueInterest() public returns (uint) {
/* Remember the initial block number */
uint currentBlockNumber = getBlockNumber();
uint accrualBlockNumberPrior = accrualBlockNumber;
/* Short-circuit accumulating 0 interest */
if (accrualBlockNumberPrior == currentBlockNumber) {
return uint(Error.NO_ERROR);
}
/* Read the previous values out of storage */
uint cashPrior = getCashPrior();
uint borrowsPrior = totalBorrows;
uint reservesPrior = totalReserves;
uint borrowIndexPrior = borrowIndex;
/* Calculate the current borrow interest rate */
uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior);
require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
/* Calculate the number of blocks elapsed since the last accrual */
(MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior);
require(mathErr == MathError.NO_ERROR, "could not calculate block delta");
/*
* Calculate the interest accumulated into borrows and reserves and the new index:
* simpleInterestFactor = borrowRate * blockDelta
* interestAccumulated = simpleInterestFactor * totalBorrows
* totalBorrowsNew = interestAccumulated + totalBorrows
* totalReservesNew = interestAccumulated * reserveFactor + totalReserves
* borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
*/
Exp memory simpleInterestFactor;
uint interestAccumulated;
uint totalBorrowsNew;
uint totalReservesNew;
uint borrowIndexNew;
(mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr));
}
(mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accrualBlockNumber = currentBlockNumber;
borrowIndex = borrowIndexNew;
totalBorrows = totalBorrowsNew;
totalReserves = totalReservesNew;
/* We emit an AccrueInterest event */
emit AccrueInterestToken(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender supplies assets into the market and receives bTokens in exchange
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0);
}
// mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
return mintFresh(msg.sender, mintAmount);
}
struct MintLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint mintTokens;
uint totalSupplyNew;
uint accountTokensNew;
uint actualMintAmount;
}
/**
* @notice User supplies assets into the market and receives bTokens in exchange
* @dev Assumes interest has already been accrued up to the current block
* @param minter The address of the account which is supplying the assets
* @param mintAmount The amount of the underlying asset to supply
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
*/
function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) {
/* Fail if mint not allowed */
uint allowed = bController.mintAllowed(address(this), minter, mintAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.MINT_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0);
}
MintLocalVars memory vars;
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call `doTransferIn` for the minter and the mintAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* `doTransferIn` reverts if anything goes wrong, since we can't be sure if
* side-effects occurred. The function returns the amount actually transferred,
* in case of a fee. On success, the bToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of bTokens to be minted:
* mintTokens = actualMintAmount / exchangeRate
*/
(vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED");
/*
* We calculate the new total supply of bTokens and minter token balance, checking for overflow:
* totalSupplyNew = totalSupply + mintTokens
* accountTokensNew = accountTokens[minter] + mintTokens
*/
(vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED");
(vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED");
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[minter] = vars.accountTokensNew;
/* We emit a Mint event, and a Transfer event */
emit MintToken(minter, vars.actualMintAmount, vars.mintTokens);
emit Transfer(address(this), minter, vars.mintTokens);
/* We call the defense hook */
bController.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems bTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of bTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, redeemTokens, 0);
}
/**
* @notice Sender redeems bTokens in exchange for a specified amount of underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemAmount The amount of underlying to receive from redeeming bTokens
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
}
// redeemFresh emits redeem-specific logs on errors, so we don't need to
return redeemFresh(msg.sender, 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems bTokens in exchange for the underlying asset
* @dev Assumes interest has already been accrued up to the current block
* @param redeemer The address of the account which is redeeming the tokens
* @param redeemTokensIn The number of bTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @param redeemAmountIn The number of underlying tokens to receive from redeeming bTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");
RedeemLocalVars memory vars;
/* exchangeRate = invoke Exchange Rate Stored() */
(vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
}
/* If redeemTokensIn > 0: */
if (redeemTokensIn > 0) {
/*
* We calculate the exchange rate and the amount of underlying to be redeemed:
* redeemTokens = redeemTokensIn
* redeemAmount = redeemTokensIn x exchangeRateCurrent
*/
vars.redeemTokens = redeemTokensIn;
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
}
} else {
/*
* We get the current exchange rate and calculate the amount to be redeemed:
* redeemTokens = redeemAmountIn / exchangeRate
* redeemAmount = redeemAmountIn
*/
(vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
}
vars.redeemAmount = redeemAmountIn;
}
/* Fail if redeem not allowed */
uint allowed = bController.redeemAllowed(address(this), redeemer, vars.redeemTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REDEEM_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
}
/*
* We calculate the new total supply and redeemer balance, checking for underflow:
* totalSupplyNew = totalSupply - redeemTokens
* accountTokensNew = accountTokens[redeemer] - redeemTokens
*/
(vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/* Fail gracefully if protocol has insufficient cash */
if (getCashPrior() < vars.redeemAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken has redeemAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(redeemer, vars.redeemAmount);
/* We write previously calculated values into storage */
totalSupply = vars.totalSupplyNew;
accountTokens[redeemer] = vars.accountTokensNew;
/* We emit a Transfer event, and a Redeem event */
emit Transfer(redeemer, address(this), vars.redeemTokens);
emit RedeemToken(redeemer, vars.redeemAmount, vars.redeemTokens);
/* We call the defense hook */
bController.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender borrows assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
}
// borrowFresh emits borrow-specific logs on errors, so we don't need to
return borrowFresh(msg.sender, borrowAmount);
}
struct BorrowLocalVars {
MathError mathErr;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
}
/**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
/**
* @notice Sender repays their own borrow
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
}
/**
* @notice Sender repays a borrow belonging to borrower
* @param borrower the account with the debt being payed off
* @param repayAmount The amount to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0);
}
// repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
return repayBorrowFresh(msg.sender, borrower, repayAmount);
}
struct RepayBorrowLocalVars {
Error err;
MathError mathErr;
uint repayAmount;
uint borrowerIndex;
uint accountBorrows;
uint accountBorrowsNew;
uint totalBorrowsNew;
uint actualRepayAmount;
}
/**
* @notice Borrows are repaid by another user (possibly the borrower).
* @param payer the account paying off the borrow
* @param borrower the account with the debt being payed off
* @param repayAmount the amount of undelrying tokens being returned
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) {
/* Fail if repayBorrow not allowed */
uint allowed = bController.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.REPAY_BORROW_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0);
}
RepayBorrowLocalVars memory vars;
/* We remember the original borrowerIndex for verification purposes */
vars.borrowerIndex = accountBorrows[borrower].interestIndex;
/* We fetch the amount the borrower owes, with accumulated interest */
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0);
}
/* If repayAmount == -1, repayAmount = accountBorrows */
if (repayAmount == uint(-1)) {
vars.repayAmount = vars.accountBorrows;
} else {
vars.repayAmount = repayAmount;
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the payer and the repayAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional repayAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);
/*
* We calculate the new borrower and total borrow balances, failing on underflow:
* accountBorrowsNew = accountBorrows - actualRepayAmount
* totalBorrowsNew = totalBorrows - actualRepayAmount
*/
(vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED");
(vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount);
require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED");
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a RepayBorrowToken event */
emit RepayBorrowToken(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);
return (uint(Error.NO_ERROR), vars.actualRepayAmount);
}
/**
* @notice The sender liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowInternal(address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal nonReentrant returns (uint, uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0);
}
error = bTokenCollateral.accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0);
}
// liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
return liquidateBorrowFresh(msg.sender, borrower, repayAmount, bTokenCollateral);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this bToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param bTokenCollateral The market in which to seize collateral from the borrower
* @param repayAmount The amount of the underlying borrowed asset to repay
* @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
*/
function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, BTokenInterface bTokenCollateral) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = bController.liquidateBorrowAllowed(address(this), address(bTokenCollateral), liquidator, borrower, repayAmount);
if (allowed != 0) {
return (failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_BCONTROLLER_REJECTION, allowed), 0);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0);
}
/* Verify bTokenCollateral market's block number equals current block number */
if (bTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0);
}
/* Fail if repayAmount = 0 */
if (repayAmount == 0) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0);
}
/* Fail if repayAmount = -1 */
if (repayAmount == uint(-1)) {
return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0);
}
/* Fail if repayBorrow fails */
(uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount);
if (repayBorrowError != uint(Error.NO_ERROR)) {
return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We calculate the number of collateral tokens that will be seized */
(uint amountSeizeError, uint seizeTokens) = bController.liquidateCalculateSeizeTokens(address(this), address(bTokenCollateral), actualRepayAmount);
require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_BCONTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED");
/* Revert if borrower collateral token balance < seizeTokens */
require(bTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH");
// If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
uint seizeError;
if (address(bTokenCollateral) == address(this)) {
seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens);
} else {
seizeError = bTokenCollateral.seize(liquidator, borrower, seizeTokens);
}
/* Revert if seize tokens fails (since we cannot be sure of side effects) */
require(seizeError == uint(Error.NO_ERROR), "token seizure failed");
/* We emit a LiquidateBorrowToken event */
emit LiquidateBorrowToken(liquidator, borrower, actualRepayAmount, address(bTokenCollateral), seizeTokens);
/* We call the defense hook */
bController.liquidateBorrowVerify(address(this), address(bTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);
return (uint(Error.NO_ERROR), actualRepayAmount);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Will fail unless called by another bToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed bToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
/**
* @notice Transfers collateral tokens (this market) to the liquidator.
* @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another BToken.
* Its absolutely critical to use msg.sender as the seizer bToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed bToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of bTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) {
/* Fail if seize not allowed */
uint allowed = bController.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_BCONTROLLER_REJECTION, allowed);
}
/* Fail if borrower = liquidator */
if (borrower == liquidator) {
return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
}
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
}
(mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
if (mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
accountTokens[borrower] = borrowerTokensNew;
accountTokens[liquidator] = liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, seizeTokens);
/* We call the defense hook */
bController.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);
return uint(Error.NO_ERROR);
}
/*** Admin Functions ***/
/**
* @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
* @param newPendingAdmin New pending admin.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
// Check caller = admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
}
// Save current value, if any, for inclusion in log
address oldPendingAdmin = pendingAdmin;
// Store pendingAdmin with value newPendingAdmin
pendingAdmin = newPendingAdmin;
// Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
* @dev Admin function for pending admin to accept role and update admin
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _acceptAdmin() external returns (uint) {
// Check caller is pendingAdmin and pendingAdmin ≠ address(0)
if (msg.sender != pendingAdmin || msg.sender == address(0)) {
return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
}
// Save current values for inclusion in log
address oldAdmin = admin;
address oldPendingAdmin = pendingAdmin;
// Store admin with value pendingAdmin
admin = pendingAdmin;
// Clear the pending value
pendingAdmin = address(0);
emit NewAdmin(oldAdmin, admin);
emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);
return uint(Error.NO_ERROR);
}
/**
* @notice Sets a new bController for the market
* @dev Admin function to set a new bController
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setBController(BControllerInterface newBController) public returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_BCONTROLLER_OWNER_CHECK);
}
BControllerInterface oldBController = bController;
// Ensure invoke bController.isBController() returns true
require(newBController.isBController(), "marker method returned false");
// Set market's bController to newBController
bController = newBController;
// Emit NewBController(oldBController, newBController)
emit NewBController(oldBController, newBController);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
* @dev Admin function to accrue interest and set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
}
// _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
return _setReserveFactorFresh(newReserveFactorMantissa);
}
/**
* @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
* @dev Admin function to set a new reserve factor
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
}
// Verify market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
}
// Check newReserveFactor ≤ maxReserveFactor
if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
}
uint oldReserveFactorMantissa = reserveFactorMantissa;
reserveFactorMantissa = newReserveFactorMantissa;
emit NewTokenReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);
return uint(Error.NO_ERROR);
}
/**
* @notice Accrues interest and reduces reserves by transferring from msg.sender
* @param addAmount Amount of addition to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
(error, ) = _addReservesFresh(addAmount);
return error;
}
/**
* @notice Add reserves by transferring from caller
* @dev Requires fresh interest accrual
* @param addAmount Amount of addition to reserves
* @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
*/
function _addReservesFresh(uint addAmount) internal returns (uint, uint) {
// totalReserves + actualAddAmount
uint totalReservesNew;
uint actualAddAmount;
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We call doTransferIn for the caller and the addAmount
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken holds an additional addAmount of cash.
* doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
* it returns the amount actually transferred, in case of a fee.
*/
actualAddAmount = doTransferIn(msg.sender, addAmount);
totalReservesNew = totalReserves + actualAddAmount;
/* Revert on overflow */
require(totalReservesNew >= totalReserves, "add reserves unexpected overflow");
// Store reserves[n+1] = reserves[n] + actualAddAmount
totalReserves = totalReservesNew;
/* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);
/* Return (NO_ERROR, actualAddAmount) */
return (uint(Error.NO_ERROR), actualAddAmount);
}
/**
* @notice Accrues interest and reduces reserves by transferring to admin
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
}
// _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
return _reduceReservesFresh(reduceAmount);
}
/**
* @notice Reduces reserves by transferring to admin
* @dev Requires fresh interest accrual
* @param reduceAmount Amount of reduction to reserves
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
// totalReserves - reduceAmount
uint totalReservesNew;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
}
// Fail gracefully if protocol has insufficient underlying cash
if (getCashPrior() < reduceAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
}
// Check reduceAmount ≤ reserves[n] (totalReserves)
if (reduceAmount > totalReserves) {
return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
totalReservesNew = totalReserves - reduceAmount;
// We checked reduceAmount <= totalReserves above, so this should never revert.
require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");
// Store reserves[n+1] = reserves[n] - reduceAmount
totalReserves = totalReservesNew;
// doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
doTransferOut(admin, reduceAmount);
emit ReservesReduced(admin, reduceAmount, totalReservesNew);
return uint(Error.NO_ERROR);
}
/**
* @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
* @dev Admin function to accrue interest and update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
uint error = accrueInterest();
if (error != uint(Error.NO_ERROR)) {
// accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
}
// _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
return _setInterestRateModelFresh(newInterestRateModel);
}
/**
* @notice updates the interest rate model (*requires fresh interest accrual)
* @dev Admin function to update the interest rate model
* @param newInterestRateModel the new interest rate model to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {
// Used to store old model for use in the event that is emitted on success
InterestRateModel oldInterestRateModel;
// Check caller is admin
if (msg.sender != admin) {
return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
}
// We fail gracefully unless market's block number equals current block number
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
}
// Track the market's current interest rate model
oldInterestRateModel = interestRateModel;
// Ensure invoke newInterestRateModel.isInterestRateModel() returns true
require(newInterestRateModel.isInterestRateModel(), "marker method returned false");
// Set the interest rate model to newInterestRateModel
interestRateModel = newInterestRateModel;
// Emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel)
emit NewMarketTokenInterestRateModel(oldInterestRateModel, newInterestRateModel);
return uint(Error.NO_ERROR);
}
/*** Safe Token ***/
/**
* @notice Gets balance of this contract in terms of the underlying
* @dev This excludes the value of the current message, if any
* @return The quantity of underlying owned by this contract
*/
function getCashPrior() internal view returns (uint);
/**
* @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
* This may revert due to insufficient balance or insufficient allowance.
*/
function doTransferIn(address from, uint amount) internal returns (uint);
/**
* @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
* If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
* If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
*/
function doTransferOut(address payable to, uint amount) internal;
/*** Reentrancy Guard ***/
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
*/
modifier nonReentrant() {
require(_notEntered, "re-entered");
_notEntered = false;
_;
_notEntered = true; // get a gas-refund post-Istanbul
}
} | /**
* @title Bird's BToken Contract
* @notice Abstract base for BTokens
*/ | NatSpecMultiLine | borrowFresh | function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
/* Fail if borrow not allowed */
uint allowed = bController.borrowAllowed(address(this), borrower, borrowAmount);
if (allowed != 0) {
return failOpaque(Error.BCONTROLLER_REJECTION, FailureInfo.BORROW_BCONTROLLER_REJECTION, allowed);
}
/* Verify market's block number equals current block number */
if (accrualBlockNumber != getBlockNumber()) {
return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
}
/* Fail gracefully if protocol has insufficient underlying cash */
if (getCashPrior() < borrowAmount) {
return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
}
BorrowLocalVars memory vars;
/*
* We calculate the new borrower and total borrow balances, failing on overflow:
* accountBorrowsNew = accountBorrows + borrowAmount
* totalBorrowsNew = totalBorrows + borrowAmount
*/
(vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
(vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
if (vars.mathErr != MathError.NO_ERROR) {
return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/*
* We invoke doTransferOut for the borrower and the borrowAmount.
* Note: The bToken must handle variations between ERC-20 and ETH underlying.
* On success, the bToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We write the previously calculated values into storage */
accountBorrows[borrower].principal = vars.accountBorrowsNew;
accountBorrows[borrower].interestIndex = borrowIndex;
totalBorrows = vars.totalBorrowsNew;
/* We emit a Borrow event */
emit BorrowToken(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);
/* We call the defense hook */
bController.borrowVerify(address(this), borrower, borrowAmount);
return uint(Error.NO_ERROR);
}
| /**
* @notice Users borrow assets from the protocol to their own address
* @param borrowAmount The amount of the underlying asset to borrow
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/ | NatSpecMultiLine | v0.5.16+commit.9c3226ce | {
"func_code_index": [
31932,
34912
]
} | 6,399 |
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