text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2014 The Bitcoin developers
  // Copyright (c) 2014-2015 The Dash developers
  // Copyright (c) 2015-2017 The CCoin developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include "main.h"
  
  #include "addrman.h"
  #include "alert.h"
  #include "chainparams.h"
  #include "checkpoints.h"
  #include "checkqueue.h"
  #include "init.h"
  #include "kernel.h"
  #include "masternode-budget.h"
  #include "masternode-payments.h"
  #include "masternodeman.h"
  #include "merkleblock.h"
  #include "net.h"
  #include "obfuscation.h"
  #include "pow.h"
  #include "spork.h"
  #include "swifttx.h"
  #include "txdb.h"
  #include "txmempool.h"
  #include "ui_interface.h"
  #include "util.h"
  #include "utilmoneystr.h"
  
  #include <sstream>
  
  #include <boost/algorithm/string/replace.hpp>
  #include <boost/filesystem.hpp>
  #include <boost/filesystem/fstream.hpp>
  #include <boost/lexical_cast.hpp>
  #include <boost/thread.hpp>
  
  using namespace boost;
  using namespace std;
  
  #if defined(NDEBUG)
  #error "CCoin cannot be compiled without assertions."
  #endif
  
  /**
   * Global state
   */
  
  CCriticalSection cs_main;
  
  BlockMap mapBlockIndex;
  map<uint256, uint256> mapProofOfStake;
  set<pair<COutPoint, unsigned int> > setStakeSeen;
  map<unsigned int, unsigned int> mapHashedBlocks;
  CChain chainActive;
  CBlockIndex* pindexBestHeader = NULL;
  int64_t nTimeBestReceived = 0;
  CWaitableCriticalSection csBestBlock;
  CConditionVariable cvBlockChange;
  int nScriptCheckThreads = 0;
  bool fImporting = false;
  bool fReindex = false;
  bool fTxIndex = true;
  bool fIsBareMultisigStd = true;
  bool fCheckBlockIndex = false;
  unsigned int nCoinCacheSize = 5000;
  bool fAlerts = DEFAULT_ALERTS;
  
  unsigned int nStakeMinAge = 60 * 60;
  int64_t nReserveBalance = 0;
  
  /** Fees smaller than this (in duffs) are considered zero fee (for relaying and mining)
   * We are ~100 times smaller then bitcoin now (2015-06-23), set minRelayTxFee only 10 times higher
   * so it's still 10 times lower comparing to bitcoin.
   */
  CFeeRate minRelayTxFee = CFeeRate(10000);
  
  CTxMemPool mempool(::minRelayTxFee);
  
  struct COrphanTx {
      CTransaction tx;
      NodeId fromPeer;
  };
  map<uint256, COrphanTx> mapOrphanTransactions;
  map<uint256, set<uint256> > mapOrphanTransactionsByPrev;
  map<uint256, int64_t> mapRejectedBlocks;
  
  
  void EraseOrphansFor(NodeId peer);
  
  static void CheckBlockIndex();
  
  /** Constant stuff for coinbase transactions we create: */
  CScript COINBASE_FLAGS;
  
  const string strMessageMagic = "DarkNet Signed Message:\n";
  
  // Internal stuff
  namespace
  {
  struct CBlockIndexWorkComparator {
      bool operator()(CBlockIndex* pa, CBlockIndex* pb) const
      {
          // First sort by most total work, ...
          if (pa->nChainWork > pb->nChainWork) return false;
          if (pa->nChainWork < pb->nChainWork) return true;
  
          // ... then by earliest time received, ...
          if (pa->nSequenceId < pb->nSequenceId) return false;
          if (pa->nSequenceId > pb->nSequenceId) return true;
  
          // Use pointer address as tie breaker (should only happen with blocks
          // loaded from disk, as those all have id 0).
          if (pa < pb) return false;
          if (pa > pb) return true;
  
          // Identical blocks.
          return false;
      }
  };
  
  CBlockIndex* pindexBestInvalid;
  
  /**
       * The set of all CBlockIndex entries with BLOCK_VALID_TRANSACTIONS (for itself and all ancestors) and
       * as good as our current tip or better. Entries may be failed, though.
       */
  set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexCandidates;
  /** Number of nodes with fSyncStarted. */
  int nSyncStarted = 0;
  /** All pairs A->B, where A (or one if its ancestors) misses transactions, but B has transactions. */
  multimap<CBlockIndex*, CBlockIndex*> mapBlocksUnlinked;
  
  CCriticalSection cs_LastBlockFile;
  std::vector<CBlockFileInfo> vinfoBlockFile;
  int nLastBlockFile = 0;
  
  /**
       * Every received block is assigned a unique and increasing identifier, so we
       * know which one to give priority in case of a fork.
       */
  CCriticalSection cs_nBlockSequenceId;
  /** Blocks loaded from disk are assigned id 0, so start the counter at 1. */
  uint32_t nBlockSequenceId = 1;
  
  /**
       * Sources of received blocks, to be able to send them reject messages or ban
       * them, if processing happens afterwards. Protected by cs_main.
       */
  map<uint256, NodeId> mapBlockSource;
  
  /** Blocks that are in flight, and that are in the queue to be downloaded. Protected by cs_main. */
  struct QueuedBlock {
      uint256 hash;
      CBlockIndex* pindex;        //! Optional.
      int64_t nTime;              //! Time of "getdata" request in microseconds.
      int nValidatedQueuedBefore; //! Number of blocks queued with validated headers (globally) at the time this one is requested.
      bool fValidatedHeaders;     //! Whether this block has validated headers at the time of request.
  };
  map<uint256, pair<NodeId, list<QueuedBlock>::iterator> > mapBlocksInFlight;
  
  /** Number of blocks in flight with validated headers. */
  int nQueuedValidatedHeaders = 0;
  
  /** Number of preferable block download peers. */
  int nPreferredDownload = 0;
  
  /** Dirty block index entries. */
  set<CBlockIndex*> setDirtyBlockIndex;
  
  /** Dirty block file entries. */
  set<int> setDirtyFileInfo;
  } // anon namespace
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // dispatching functions
  //
  
  // These functions dispatch to one or all registered wallets
  
  namespace
  {
  struct CMainSignals {
      /** Notifies listeners of updated transaction data (transaction, and optionally the block it is found in. */
      boost::signals2::signal<void(const CTransaction&, const CBlock*)> SyncTransaction;
      /** Notifies listeners of an erased transaction (currently disabled, requires transaction replacement). */
      boost::signals2::signal<void(const uint256&)> EraseTransaction;
      /** Notifies listeners of an updated transaction without new data (for now: a coinbase potentially becoming visible). */
      boost::signals2::signal<void(const uint256&)> UpdatedTransaction;
      /** Notifies listeners of a new active block chain. */
      boost::signals2::signal<void(const CBlockLocator&)> SetBestChain;
      /** Notifies listeners about an inventory item being seen on the network. */
      boost::signals2::signal<void(const uint256&)> Inventory;
      /** Tells listeners to broadcast their data. */
      boost::signals2::signal<void()> Broadcast;
      /** Notifies listeners of a block validation result */
      boost::signals2::signal<void(const CBlock&, const CValidationState&)> BlockChecked;
  } g_signals;
  
  } // anon namespace
  
  void RegisterValidationInterface(CValidationInterface* pwalletIn)
  {
      g_signals.SyncTransaction.connect(boost::bind(&CValidationInterface::SyncTransaction, pwalletIn, _1, _2));
      g_signals.EraseTransaction.connect(boost::bind(&CValidationInterface::EraseFromWallet, pwalletIn, _1));
      g_signals.UpdatedTransaction.connect(boost::bind(&CValidationInterface::UpdatedTransaction, pwalletIn, _1));
      g_signals.SetBestChain.connect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
      g_signals.Inventory.connect(boost::bind(&CValidationInterface::Inventory, pwalletIn, _1));
      g_signals.Broadcast.connect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn));
      g_signals.BlockChecked.connect(boost::bind(&CValidationInterface::BlockChecked, pwalletIn, _1, _2));
  }
  
  void UnregisterValidationInterface(CValidationInterface* pwalletIn)
  {
      g_signals.BlockChecked.disconnect(boost::bind(&CValidationInterface::BlockChecked, pwalletIn, _1, _2));
      g_signals.Broadcast.disconnect(boost::bind(&CValidationInterface::ResendWalletTransactions, pwalletIn));
      g_signals.Inventory.disconnect(boost::bind(&CValidationInterface::Inventory, pwalletIn, _1));
      g_signals.SetBestChain.disconnect(boost::bind(&CValidationInterface::SetBestChain, pwalletIn, _1));
      g_signals.UpdatedTransaction.disconnect(boost::bind(&CValidationInterface::UpdatedTransaction, pwalletIn, _1));
      g_signals.EraseTransaction.disconnect(boost::bind(&CValidationInterface::EraseFromWallet, pwalletIn, _1));
      g_signals.SyncTransaction.disconnect(boost::bind(&CValidationInterface::SyncTransaction, pwalletIn, _1, _2));
  }
  
  void UnregisterAllValidationInterfaces()
  {
      g_signals.BlockChecked.disconnect_all_slots();
      g_signals.Broadcast.disconnect_all_slots();
      g_signals.Inventory.disconnect_all_slots();
      g_signals.SetBestChain.disconnect_all_slots();
      g_signals.UpdatedTransaction.disconnect_all_slots();
      g_signals.EraseTransaction.disconnect_all_slots();
      g_signals.SyncTransaction.disconnect_all_slots();
  }
  
  void SyncWithWallets(const CTransaction& tx, const CBlock* pblock)
  {
      g_signals.SyncTransaction(tx, pblock);
  }
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // Registration of network node signals.
  //
  
  namespace
  {
  struct CBlockReject {
      unsigned char chRejectCode;
      string strRejectReason;
      uint256 hashBlock;
  };
  
  /**
   * Maintain validation-specific state about nodes, protected by cs_main, instead
   * by CNode's own locks. This simplifies asynchronous operation, where
   * processing of incoming data is done after the ProcessMessage call returns,
   * and we're no longer holding the node's locks.
   */
  struct CNodeState {
      //! The peer's address
      CService address;
      //! Whether we have a fully established connection.
      bool fCurrentlyConnected;
      //! Accumulated misbehaviour score for this peer.
      int nMisbehavior;
      //! Whether this peer should be disconnected and banned (unless whitelisted).
      bool fShouldBan;
      //! String name of this peer (debugging/logging purposes).
      std::string name;
      //! List of asynchronously-determined block rejections to notify this peer about.
      std::vector<CBlockReject> rejects;
      //! The best known block we know this peer has announced.
      CBlockIndex* pindexBestKnownBlock;
      //! The hash of the last unknown block this peer has announced.
      uint256 hashLastUnknownBlock;
      //! The last full block we both have.
      CBlockIndex* pindexLastCommonBlock;
      //! Whether we've started headers synchronization with this peer.
      bool fSyncStarted;
      //! Since when we're stalling block download progress (in microseconds), or 0.
      int64_t nStallingSince;
      list<QueuedBlock> vBlocksInFlight;
      int nBlocksInFlight;
      //! Whether we consider this a preferred download peer.
      bool fPreferredDownload;
  
      CNodeState()
      {
          fCurrentlyConnected = false;
          nMisbehavior = 0;
          fShouldBan = false;
          pindexBestKnownBlock = NULL;
          hashLastUnknownBlock = uint256(0);
          pindexLastCommonBlock = NULL;
          fSyncStarted = false;
          nStallingSince = 0;
          nBlocksInFlight = 0;
          fPreferredDownload = false;
      }
  };
  
  /** Map maintaining per-node state. Requires cs_main. */
  map<NodeId, CNodeState> mapNodeState;
  
  // Requires cs_main.
  CNodeState* State(NodeId pnode)
  {
      map<NodeId, CNodeState>::iterator it = mapNodeState.find(pnode);
      if (it == mapNodeState.end())
          return NULL;
      return &it->second;
  }
  
  int GetHeight()
  {
      while (true) {
          TRY_LOCK(cs_main, lockMain);
          if (!lockMain) {
              MilliSleep(50);
              continue;
          }
          return chainActive.Height();
      }
  }
  
  void UpdatePreferredDownload(CNode* node, CNodeState* state)
  {
      nPreferredDownload -= state->fPreferredDownload;
  
      // Whether this node should be marked as a preferred download node.
      state->fPreferredDownload = (!node->fInbound || node->fWhitelisted) && !node->fOneShot && !node->fClient;
  
      nPreferredDownload += state->fPreferredDownload;
  }
  
  void InitializeNode(NodeId nodeid, const CNode* pnode)
  {
      LOCK(cs_main);
      CNodeState& state = mapNodeState.insert(std::make_pair(nodeid, CNodeState())).first->second;
      state.name = pnode->addrName;
      state.address = pnode->addr;
  }
  
  void FinalizeNode(NodeId nodeid)
  {
      LOCK(cs_main);
      CNodeState* state = State(nodeid);
  
      if (state->fSyncStarted)
          nSyncStarted--;
  
      if (state->nMisbehavior == 0 && state->fCurrentlyConnected) {
          AddressCurrentlyConnected(state->address);
      }
  
      BOOST_FOREACH (const QueuedBlock& entry, state->vBlocksInFlight)
          mapBlocksInFlight.erase(entry.hash);
      EraseOrphansFor(nodeid);
      nPreferredDownload -= state->fPreferredDownload;
  
      mapNodeState.erase(nodeid);
  }
  
  // Requires cs_main.
  void MarkBlockAsReceived(const uint256& hash)
  {
      map<uint256, pair<NodeId, list<QueuedBlock>::iterator> >::iterator itInFlight = mapBlocksInFlight.find(hash);
      if (itInFlight != mapBlocksInFlight.end()) {
          CNodeState* state = State(itInFlight->second.first);
          nQueuedValidatedHeaders -= itInFlight->second.second->fValidatedHeaders;
          state->vBlocksInFlight.erase(itInFlight->second.second);
          state->nBlocksInFlight--;
          state->nStallingSince = 0;
          mapBlocksInFlight.erase(itInFlight);
      }
  }
  
  // Requires cs_main.
  void MarkBlockAsInFlight(NodeId nodeid, const uint256& hash, CBlockIndex* pindex = NULL)
  {
      CNodeState* state = State(nodeid);
      assert(state != NULL);
  
      // Make sure it's not listed somewhere already.
      MarkBlockAsReceived(hash);
  
      QueuedBlock newentry = {hash, pindex, GetTimeMicros(), nQueuedValidatedHeaders, pindex != NULL};
      nQueuedValidatedHeaders += newentry.fValidatedHeaders;
      list<QueuedBlock>::iterator it = state->vBlocksInFlight.insert(state->vBlocksInFlight.end(), newentry);
      state->nBlocksInFlight++;
      mapBlocksInFlight[hash] = std::make_pair(nodeid, it);
  }
  
  /** Check whether the last unknown block a peer advertized is not yet known. */
  void ProcessBlockAvailability(NodeId nodeid)
  {
      CNodeState* state = State(nodeid);
      assert(state != NULL);
  
      if (state->hashLastUnknownBlock != 0) {
          BlockMap::iterator itOld = mapBlockIndex.find(state->hashLastUnknownBlock);
          if (itOld != mapBlockIndex.end() && itOld->second->nChainWork > 0) {
              if (state->pindexBestKnownBlock == NULL || itOld->second->nChainWork >= state->pindexBestKnownBlock->nChainWork)
                  state->pindexBestKnownBlock = itOld->second;
              state->hashLastUnknownBlock = uint256(0);
          }
      }
  }
  
  /** Update tracking information about which blocks a peer is assumed to have. */
  void UpdateBlockAvailability(NodeId nodeid, const uint256& hash)
  {
      CNodeState* state = State(nodeid);
      assert(state != NULL);
  
      ProcessBlockAvailability(nodeid);
  
      BlockMap::iterator it = mapBlockIndex.find(hash);
      if (it != mapBlockIndex.end() && it->second->nChainWork > 0) {
          // An actually better block was announced.
          if (state->pindexBestKnownBlock == NULL || it->second->nChainWork >= state->pindexBestKnownBlock->nChainWork)
              state->pindexBestKnownBlock = it->second;
      } else {
          // An unknown block was announced; just assume that the latest one is the best one.
          state->hashLastUnknownBlock = hash;
      }
  }
  
  /** Find the last common ancestor two blocks have.
   *  Both pa and pb must be non-NULL. */
  CBlockIndex* LastCommonAncestor(CBlockIndex* pa, CBlockIndex* pb)
  {
      if (pa->nHeight > pb->nHeight) {
          pa = pa->GetAncestor(pb->nHeight);
      } else if (pb->nHeight > pa->nHeight) {
          pb = pb->GetAncestor(pa->nHeight);
      }
  
      while (pa != pb && pa && pb) {
          pa = pa->pprev;
          pb = pb->pprev;
      }
  
      // Eventually all chain branches meet at the genesis block.
      assert(pa == pb);
      return pa;
  }
  
  /** Update pindexLastCommonBlock and add not-in-flight missing successors to vBlocks, until it has
   *  at most count entries. */
  void FindNextBlocksToDownload(NodeId nodeid, unsigned int count, std::vector<CBlockIndex*>& vBlocks, NodeId& nodeStaller)
  {
      if (count == 0)
          return;
  
      vBlocks.reserve(vBlocks.size() + count);
      CNodeState* state = State(nodeid);
      assert(state != NULL);
  
      // Make sure pindexBestKnownBlock is up to date, we'll need it.
      ProcessBlockAvailability(nodeid);
  
      if (state->pindexBestKnownBlock == NULL || state->pindexBestKnownBlock->nChainWork < chainActive.Tip()->nChainWork) {
          // This peer has nothing interesting.
          return;
      }
  
      if (state->pindexLastCommonBlock == NULL) {
          // Bootstrap quickly by guessing a parent of our best tip is the forking point.
          // Guessing wrong in either direction is not a problem.
          state->pindexLastCommonBlock = chainActive[std::min(state->pindexBestKnownBlock->nHeight, chainActive.Height())];
      }
  
      // If the peer reorganized, our previous pindexLastCommonBlock may not be an ancestor
      // of their current tip anymore. Go back enough to fix that.
      state->pindexLastCommonBlock = LastCommonAncestor(state->pindexLastCommonBlock, state->pindexBestKnownBlock);
      if (state->pindexLastCommonBlock == state->pindexBestKnownBlock)
          return;
  
      std::vector<CBlockIndex*> vToFetch;
      CBlockIndex* pindexWalk = state->pindexLastCommonBlock;
      // Never fetch further than the best block we know the peer has, or more than BLOCK_DOWNLOAD_WINDOW + 1 beyond the last
      // linked block we have in common with this peer. The +1 is so we can detect stalling, namely if we would be able to
      // download that next block if the window were 1 larger.
      int nWindowEnd = state->pindexLastCommonBlock->nHeight + BLOCK_DOWNLOAD_WINDOW;
      int nMaxHeight = std::min<int>(state->pindexBestKnownBlock->nHeight, nWindowEnd + 1);
      NodeId waitingfor = -1;
      while (pindexWalk->nHeight < nMaxHeight) {
          // Read up to 128 (or more, if more blocks than that are needed) successors of pindexWalk (towards
          // pindexBestKnownBlock) into vToFetch. We fetch 128, because CBlockIndex::GetAncestor may be as expensive
          // as iterating over ~100 CBlockIndex* entries anyway.
          int nToFetch = std::min(nMaxHeight - pindexWalk->nHeight, std::max<int>(count - vBlocks.size(), 128));
          vToFetch.resize(nToFetch);
          pindexWalk = state->pindexBestKnownBlock->GetAncestor(pindexWalk->nHeight + nToFetch);
          vToFetch[nToFetch - 1] = pindexWalk;
          for (unsigned int i = nToFetch - 1; i > 0; i--) {
              vToFetch[i - 1] = vToFetch[i]->pprev;
          }
  
          // Iterate over those blocks in vToFetch (in forward direction), adding the ones that
          // are not yet downloaded and not in flight to vBlocks. In the mean time, update
          // pindexLastCommonBlock as long as all ancestors are already downloaded.
          BOOST_FOREACH (CBlockIndex* pindex, vToFetch) {
              if (!pindex->IsValid(BLOCK_VALID_TREE)) {
                  // We consider the chain that this peer is on invalid.
                  return;
              }
              if (pindex->nStatus & BLOCK_HAVE_DATA) {
                  if (pindex->nChainTx)
                      state->pindexLastCommonBlock = pindex;
              } else if (mapBlocksInFlight.count(pindex->GetBlockHash()) == 0) {
                  // The block is not already downloaded, and not yet in flight.
                  if (pindex->nHeight > nWindowEnd) {
                      // We reached the end of the window.
                      if (vBlocks.size() == 0 && waitingfor != nodeid) {
                          // We aren't able to fetch anything, but we would be if the download window was one larger.
                          nodeStaller = waitingfor;
                      }
                      return;
                  }
                  vBlocks.push_back(pindex);
                  if (vBlocks.size() == count) {
                      return;
                  }
              } else if (waitingfor == -1) {
                  // This is the first already-in-flight block.
                  waitingfor = mapBlocksInFlight[pindex->GetBlockHash()].first;
              }
          }
      }
  }
  
  } // anon namespace
  
  bool GetNodeStateStats(NodeId nodeid, CNodeStateStats& stats)
  {
      LOCK(cs_main);
      CNodeState* state = State(nodeid);
      if (state == NULL)
          return false;
      stats.nMisbehavior = state->nMisbehavior;
      stats.nSyncHeight = state->pindexBestKnownBlock ? state->pindexBestKnownBlock->nHeight : -1;
      stats.nCommonHeight = state->pindexLastCommonBlock ? state->pindexLastCommonBlock->nHeight : -1;
      BOOST_FOREACH (const QueuedBlock& queue, state->vBlocksInFlight) {
          if (queue.pindex)
              stats.vHeightInFlight.push_back(queue.pindex->nHeight);
      }
      return true;
  }
  
  void RegisterNodeSignals(CNodeSignals& nodeSignals)
  {
      nodeSignals.GetHeight.connect(&GetHeight);
      nodeSignals.ProcessMessages.connect(&ProcessMessages);
      nodeSignals.SendMessages.connect(&SendMessages);
      nodeSignals.InitializeNode.connect(&InitializeNode);
      nodeSignals.FinalizeNode.connect(&FinalizeNode);
  }
  
  void UnregisterNodeSignals(CNodeSignals& nodeSignals)
  {
      nodeSignals.GetHeight.disconnect(&GetHeight);
      nodeSignals.ProcessMessages.disconnect(&ProcessMessages);
      nodeSignals.SendMessages.disconnect(&SendMessages);
      nodeSignals.InitializeNode.disconnect(&InitializeNode);
      nodeSignals.FinalizeNode.disconnect(&FinalizeNode);
  }
  
  CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator)
  {
      // Find the first block the caller has in the main chain
      BOOST_FOREACH (const uint256& hash, locator.vHave) {
          BlockMap::iterator mi = mapBlockIndex.find(hash);
          if (mi != mapBlockIndex.end()) {
              CBlockIndex* pindex = (*mi).second;
              if (chain.Contains(pindex))
                  return pindex;
          }
      }
      return chain.Genesis();
  }
  
  CCoinsViewCache* pcoinsTip = NULL;
  CBlockTreeDB* pblocktree = NULL;
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // mapOrphanTransactions
  //
  
  bool AddOrphanTx(const CTransaction& tx, NodeId peer)
  {
      uint256 hash = tx.GetHash();
      if (mapOrphanTransactions.count(hash))
          return false;
  
      // Ignore big transactions, to avoid a
      // send-big-orphans memory exhaustion attack. If a peer has a legitimate
      // large transaction with a missing parent then we assume
      // it will rebroadcast it later, after the parent transaction(s)
      // have been mined or received.
      // 10,000 orphans, each of which is at most 5,000 bytes big is
      // at most 500 megabytes of orphans:
      unsigned int sz = tx.GetSerializeSize(SER_NETWORK, CTransaction::CURRENT_VERSION);
      if (sz > 5000) {
          LogPrint("mempool", "ignoring large orphan tx (size: %u, hash: %s)\n", sz, hash.ToString());
          return false;
      }
  
      mapOrphanTransactions[hash].tx = tx;
      mapOrphanTransactions[hash].fromPeer = peer;
      BOOST_FOREACH (const CTxIn& txin, tx.vin)
          mapOrphanTransactionsByPrev[txin.prevout.hash].insert(hash);
  
      LogPrint("mempool", "stored orphan tx %s (mapsz %u prevsz %u)\n", hash.ToString(),
          mapOrphanTransactions.size(), mapOrphanTransactionsByPrev.size());
      return true;
  }
  
  void static EraseOrphanTx(uint256 hash)
  {
      map<uint256, COrphanTx>::iterator it = mapOrphanTransactions.find(hash);
      if (it == mapOrphanTransactions.end())
          return;
      BOOST_FOREACH (const CTxIn& txin, it->second.tx.vin) {
          map<uint256, set<uint256> >::iterator itPrev = mapOrphanTransactionsByPrev.find(txin.prevout.hash);
          if (itPrev == mapOrphanTransactionsByPrev.end())
              continue;
          itPrev->second.erase(hash);
          if (itPrev->second.empty())
              mapOrphanTransactionsByPrev.erase(itPrev);
      }
      mapOrphanTransactions.erase(it);
  }
  
  void EraseOrphansFor(NodeId peer)
  {
      int nErased = 0;
      map<uint256, COrphanTx>::iterator iter = mapOrphanTransactions.begin();
      while (iter != mapOrphanTransactions.end()) {
          map<uint256, COrphanTx>::iterator maybeErase = iter++; // increment to avoid iterator becoming invalid
          if (maybeErase->second.fromPeer == peer) {
              EraseOrphanTx(maybeErase->second.tx.GetHash());
              ++nErased;
          }
      }
      if (nErased > 0) LogPrint("mempool", "Erased %d orphan tx from peer %d\n", nErased, peer);
  }
  
  
  unsigned int LimitOrphanTxSize(unsigned int nMaxOrphans)
  {
      unsigned int nEvicted = 0;
      while (mapOrphanTransactions.size() > nMaxOrphans) {
          // Evict a random orphan:
          uint256 randomhash = GetRandHash();
          map<uint256, COrphanTx>::iterator it = mapOrphanTransactions.lower_bound(randomhash);
          if (it == mapOrphanTransactions.end())
              it = mapOrphanTransactions.begin();
          EraseOrphanTx(it->first);
          ++nEvicted;
      }
      return nEvicted;
  }
  
  bool IsStandardTx(const CTransaction& tx, string& reason)
  {
      AssertLockHeld(cs_main);
      if (tx.nVersion > CTransaction::CURRENT_VERSION || tx.nVersion < 1) {
          reason = "version";
          return false;
      }
  
      // Treat non-final transactions as non-standard to prevent a specific type
      // of double-spend attack, as well as DoS attacks. (if the transaction
      // can't be mined, the attacker isn't expending resources broadcasting it)
      // Basically we don't want to propagate transactions that can't be included in
      // the next block.
      //
      // However, IsFinalTx() is confusing... Without arguments, it uses
      // chainActive.Height() to evaluate nLockTime; when a block is accepted, chainActive.Height()
      // is set to the value of nHeight in the block. However, when IsFinalTx()
      // is called within CBlock::AcceptBlock(), the height of the block *being*
      // evaluated is what is used. Thus if we want to know if a transaction can
      // be part of the *next* block, we need to call IsFinalTx() with one more
      // than chainActive.Height().
      //
      // Timestamps on the other hand don't get any special treatment, because we
      // can't know what timestamp the next block will have, and there aren't
      // timestamp applications where it matters.
      if (!IsFinalTx(tx, chainActive.Height() + 1)) {
          reason = "non-final";
          return false;
      }
  
      // Extremely large transactions with lots of inputs can cost the network
      // almost as much to process as they cost the sender in fees, because
      // computing signature hashes is O(ninputs*txsize). Limiting transactions
      // to MAX_STANDARD_TX_SIZE mitigates CPU exhaustion attacks.
      unsigned int sz = tx.GetSerializeSize(SER_NETWORK, CTransaction::CURRENT_VERSION);
      if (sz >= MAX_STANDARD_TX_SIZE) {
          reason = "tx-size";
          return false;
      }
  
      BOOST_FOREACH (const CTxIn& txin, tx.vin) {
          // Biggest 'standard' txin is a 15-of-15 P2SH multisig with compressed
          // keys. (remember the 520 byte limit on redeemScript size) That works
          // out to a (15*(33+1))+3=513 byte redeemScript, 513+1+15*(73+1)+3=1627
          // bytes of scriptSig, which we round off to 1650 bytes for some minor
          // future-proofing. That's also enough to spend a 20-of-20
          // CHECKMULTISIG scriptPubKey, though such a scriptPubKey is not
          // considered standard)
          if (txin.scriptSig.size() > 1650) {
              reason = "scriptsig-size";
              return false;
          }
          if (!txin.scriptSig.IsPushOnly()) {
              reason = "scriptsig-not-pushonly";
              return false;
          }
      }
  
      unsigned int nDataOut = 0;
      txnouttype whichType;
      BOOST_FOREACH (const CTxOut& txout, tx.vout) {
          if (!::IsStandard(txout.scriptPubKey, whichType)) {
              reason = "scriptpubkey";
              return false;
          }
  
          if (whichType == TX_NULL_DATA)
              nDataOut++;
          else if ((whichType == TX_MULTISIG) && (!fIsBareMultisigStd)) {
              reason = "bare-multisig";
              return false;
          } else if (txout.IsDust(::minRelayTxFee)) {
              reason = "dust";
              return false;
          }
      }
  
      // only one OP_RETURN txout is permitted
      if (nDataOut > 1) {
          reason = "multi-op-return";
          return false;
      }
  
      return true;
  }
  
  bool IsFinalTx(const CTransaction& tx, int nBlockHeight, int64_t nBlockTime)
  {
      AssertLockHeld(cs_main);
      // Time based nLockTime implemented in 0.1.6
      if (tx.nLockTime == 0)
          return true;
      if (nBlockHeight == 0)
          nBlockHeight = chainActive.Height();
      if (nBlockTime == 0)
          nBlockTime = GetAdjustedTime();
      if ((int64_t)tx.nLockTime < ((int64_t)tx.nLockTime < LOCKTIME_THRESHOLD ? (int64_t)nBlockHeight : nBlockTime))
          return true;
      BOOST_FOREACH (const CTxIn& txin, tx.vin)
          if (!txin.IsFinal())
              return false;
      return true;
  }
  
  /**
   * Check transaction inputs to mitigate two
   * potential denial-of-service attacks:
   *
   * 1. scriptSigs with extra data stuffed into them,
   *    not consumed by scriptPubKey (or P2SH script)
   * 2. P2SH scripts with a crazy number of expensive
   *    CHECKSIG/CHECKMULTISIG operations
   */
  bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs)
  {
      if (tx.IsCoinBase())
          return true; // Coinbases don't use vin normally
  
      for (unsigned int i = 0; i < tx.vin.size(); i++) {
          const CTxOut& prev = mapInputs.GetOutputFor(tx.vin[i]);
  
          vector<vector<unsigned char> > vSolutions;
          txnouttype whichType;
          // get the scriptPubKey corresponding to this input:
          const CScript& prevScript = prev.scriptPubKey;
          if (!Solver(prevScript, whichType, vSolutions))
              return false;
          int nArgsExpected = ScriptSigArgsExpected(whichType, vSolutions);
          if (nArgsExpected < 0)
              return false;
  
          // Transactions with extra stuff in their scriptSigs are
          // non-standard. Note that this EvalScript() call will
          // be quick, because if there are any operations
          // beside "push data" in the scriptSig
          // IsStandard() will have already returned false
          // and this method isn't called.
          vector<vector<unsigned char> > stack;
          if (!EvalScript(stack, tx.vin[i].scriptSig, false, BaseSignatureChecker()))
              return false;
  
          if (whichType == TX_SCRIPTHASH) {
              if (stack.empty())
                  return false;
              CScript subscript(stack.back().begin(), stack.back().end());
              vector<vector<unsigned char> > vSolutions2;
              txnouttype whichType2;
              if (Solver(subscript, whichType2, vSolutions2)) {
                  int tmpExpected = ScriptSigArgsExpected(whichType2, vSolutions2);
                  if (tmpExpected < 0)
                      return false;
                  nArgsExpected += tmpExpected;
              } else {
                  // Any other Script with less than 15 sigops OK:
                  unsigned int sigops = subscript.GetSigOpCount(true);
                  // ... extra data left on the stack after execution is OK, too:
                  return (sigops <= MAX_P2SH_SIGOPS);
              }
          }
  
          if (stack.size() != (unsigned int)nArgsExpected)
              return false;
      }
  
      return true;
  }
  
  unsigned int GetLegacySigOpCount(const CTransaction& tx)
  {
      unsigned int nSigOps = 0;
      BOOST_FOREACH (const CTxIn& txin, tx.vin) {
          nSigOps += txin.scriptSig.GetSigOpCount(false);
      }
      BOOST_FOREACH (const CTxOut& txout, tx.vout) {
          nSigOps += txout.scriptPubKey.GetSigOpCount(false);
      }
      return nSigOps;
  }
  
  unsigned int GetP2SHSigOpCount(const CTransaction& tx, const CCoinsViewCache& inputs)
  {
      if (tx.IsCoinBase())
          return 0;
  
      unsigned int nSigOps = 0;
      for (unsigned int i = 0; i < tx.vin.size(); i++) {
          const CTxOut& prevout = inputs.GetOutputFor(tx.vin[i]);
          if (prevout.scriptPubKey.IsPayToScriptHash())
              nSigOps += prevout.scriptPubKey.GetSigOpCount(tx.vin[i].scriptSig);
      }
      return nSigOps;
  }
  
  int GetInputAge(CTxIn& vin)
  {
      CCoinsView viewDummy;
      CCoinsViewCache view(&viewDummy);
      {
          LOCK(mempool.cs);
          CCoinsViewMemPool viewMempool(pcoinsTip, mempool);
          view.SetBackend(viewMempool); // temporarily switch cache backend to db+mempool view
  
          const CCoins* coins = view.AccessCoins(vin.prevout.hash);
  
          if (coins) {
              if (coins->nHeight < 0) return 0;
              return (chainActive.Tip()->nHeight + 1) - coins->nHeight;
          } else
              return -1;
      }
  }
  
  int GetInputAgeIX(uint256 nTXHash, CTxIn& vin)
  {
      int sigs = 0;
      int nResult = GetInputAge(vin);
      if (nResult < 0) nResult = 0;
  
      if (nResult < 6) {
          std::map<uint256, CTransactionLock>::iterator i = mapTxLocks.find(nTXHash);
          if (i != mapTxLocks.end()) {
              sigs = (*i).second.CountSignatures();
          }
          if (sigs >= SWIFTTX_SIGNATURES_REQUIRED) {
              return nSwiftTXDepth + nResult;
          }
      }
  
      return -1;
  }
  
  int GetIXConfirmations(uint256 nTXHash)
  {
      int sigs = 0;
  
      std::map<uint256, CTransactionLock>::iterator i = mapTxLocks.find(nTXHash);
      if (i != mapTxLocks.end()) {
          sigs = (*i).second.CountSignatures();
      }
      if (sigs >= SWIFTTX_SIGNATURES_REQUIRED) {
          return nSwiftTXDepth;
      }
  
      return 0;
  }
  
  // ppcoin: total coin age spent in transaction, in the unit of coin-days.
  // Only those coins meeting minimum age requirement counts. As those
  // transactions not in main chain are not currently indexed so we
  // might not find out about their coin age. Older transactions are
  // guaranteed to be in main chain by sync-checkpoint. This rule is
  // introduced to help nodes establish a consistent view of the coin
  // age (trust score) of competing branches.
  bool GetCoinAge(const CTransaction& tx, const unsigned int nTxTime, uint64_t& nCoinAge)
  {
      uint256 bnCentSecond = 0; // coin age in the unit of cent-seconds
      nCoinAge = 0;
  
      CBlockIndex* pindex = NULL;
      BOOST_FOREACH (const CTxIn& txin, tx.vin) {
          // First try finding the previous transaction in database
          CTransaction txPrev;
          uint256 hashBlockPrev;
          if (!GetTransaction(txin.prevout.hash, txPrev, hashBlockPrev, true)) {
              LogPrintf("GetCoinAge: failed to find vin transaction \n");
              continue; // previous transaction not in main chain
          }
  
          BlockMap::iterator it = mapBlockIndex.find(hashBlockPrev);
          if (it != mapBlockIndex.end())
              pindex = it->second;
          else {
              LogPrintf("GetCoinAge() failed to find block index \n");
              continue;
          }
  
          // Read block header
          CBlockHeader prevblock = pindex->GetBlockHeader();
  
          if (prevblock.nTime + nStakeMinAge > nTxTime)
              continue; // only count coins meeting min age requirement
  
          if (nTxTime < prevblock.nTime) {
              LogPrintf("GetCoinAge: Timestamp Violation: txtime less than txPrev.nTime");
              return false; // Transaction timestamp violation
          }
  
          int64_t nValueIn = txPrev.vout[txin.prevout.n].nValue;
          bnCentSecond += uint256(nValueIn) * (nTxTime - prevblock.nTime);
      }
  
      uint256 bnCoinDay = bnCentSecond / COIN / (24 * 60 * 60);
      LogPrintf("coin age bnCoinDay=%s\n", bnCoinDay.ToString().c_str());
      nCoinAge = bnCoinDay.GetCompact();
      return true;
  }
  
  bool CheckTransaction(const CTransaction& tx, CValidationState& state)
  {
      // Basic checks that don't depend on any context
      if (tx.vin.empty())
          return state.DoS(10, error("CheckTransaction() : vin empty"),
              REJECT_INVALID, "bad-txns-vin-empty");
      if (tx.vout.empty())
          return state.DoS(10, error("CheckTransaction() : vout empty"),
              REJECT_INVALID, "bad-txns-vout-empty");
      // Size limits
      if (::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
          return state.DoS(100, error("CheckTransaction() : size limits failed"),
              REJECT_INVALID, "bad-txns-oversize");
  
      // Check for negative or overflow output values
      CAmount nValueOut = 0;
      BOOST_FOREACH (const CTxOut& txout, tx.vout) {
          if (txout.IsEmpty() && !tx.IsCoinBase() && !tx.IsCoinStake())
              return state.DoS(100, error("CheckTransaction(): txout empty for user transaction"));
  
          if (txout.nValue < 0)
              return state.DoS(100, error("CheckTransaction() : txout.nValue negative"),
                  REJECT_INVALID, "bad-txns-vout-negative");
          if (txout.nValue > MAX_MONEY)
              return state.DoS(100, error("CheckTransaction() : txout.nValue too high"),
                  REJECT_INVALID, "bad-txns-vout-toolarge");
          nValueOut += txout.nValue;
          if (!MoneyRange(nValueOut))
              return state.DoS(100, error("CheckTransaction() : txout total out of range"),
                  REJECT_INVALID, "bad-txns-txouttotal-toolarge");
      }
  
      // Check for duplicate inputs
      set<COutPoint> vInOutPoints;
      BOOST_FOREACH (const CTxIn& txin, tx.vin) {
          if (vInOutPoints.count(txin.prevout))
              return state.DoS(100, error("CheckTransaction() : duplicate inputs"),
                  REJECT_INVALID, "bad-txns-inputs-duplicate");
          vInOutPoints.insert(txin.prevout);
      }
  
      if (tx.IsCoinBase()) {
          if (/*tx.vin[0].scriptSig.size() < 2 || */ tx.vin[0].scriptSig.size() > 150)
              return state.DoS(100, error("CheckTransaction() : coinbase script size=%d", tx.vin[0].scriptSig.size()),
                  REJECT_INVALID, "bad-cb-length");
      } else {
          BOOST_FOREACH (const CTxIn& txin, tx.vin)
              if (txin.prevout.IsNull())
                  return state.DoS(10, error("CheckTransaction() : prevout is null"),
                      REJECT_INVALID, "bad-txns-prevout-null");
      }
  
      return true;
  }
  
  bool CheckFinalTx(const CTransaction& tx, int flags)
  {
      AssertLockHeld(cs_main);
  
      // By convention a negative value for flags indicates that the
      // current network-enforced consensus rules should be used. In
      // a future soft-fork scenario that would mean checking which
      // rules would be enforced for the next block and setting the
      // appropriate flags. At the present time no soft-forks are
      // scheduled, so no flags are set.
      flags = std::max(flags, 0);
  
      // CheckFinalTx() uses chainActive.Height()+1 to evaluate
      // nLockTime because when IsFinalTx() is called within
      // CBlock::AcceptBlock(), the height of the block *being*
      // evaluated is what is used. Thus if we want to know if a
      // transaction can be part of the *next* block, we need to call
      // IsFinalTx() with one more than chainActive.Height().
      const int nBlockHeight = chainActive.Height() + 1;
  
      // BIP113 will require that time-locked transactions have nLockTime set to
      // less than the median time of the previous block they're contained in.
      // When the next block is created its previous block will be the current
      // chain tip, so we use that to calculate the median time passed to
      // IsFinalTx() if LOCKTIME_MEDIAN_TIME_PAST is set.
      const int64_t nBlockTime = (flags & LOCKTIME_MEDIAN_TIME_PAST) ? chainActive.Tip()->GetMedianTimePast() : GetAdjustedTime();
  
      return IsFinalTx(tx, nBlockHeight, nBlockTime);
  }
  
  CAmount GetMinRelayFee(const CTransaction& tx, unsigned int nBytes, bool fAllowFree)
  {
      {
          LOCK(mempool.cs);
          uint256 hash = tx.GetHash();
          double dPriorityDelta = 0;
          CAmount nFeeDelta = 0;
          mempool.ApplyDeltas(hash, dPriorityDelta, nFeeDelta);
          if (dPriorityDelta > 0 || nFeeDelta > 0)
              return 0;
      }
  
      CAmount nMinFee = ::minRelayTxFee.GetFee(nBytes);
  
      if (fAllowFree) {
          // There is a free transaction area in blocks created by most miners,
          // * If we are relaying we allow transactions up to DEFAULT_BLOCK_PRIORITY_SIZE - 1000
          //   to be considered to fall into this category. We don't want to encourage sending
          //   multiple transactions instead of one big transaction to avoid fees.
          if (nBytes < (DEFAULT_BLOCK_PRIORITY_SIZE - 1000))
              nMinFee = 0;
      }
  
      if (!MoneyRange(nMinFee))
          nMinFee = MAX_MONEY;
      return nMinFee;
  }
  
  
  bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState& state, const CTransaction& tx, bool fLimitFree, bool* pfMissingInputs, bool fRejectInsaneFee, bool ignoreFees)
  {
      AssertLockHeld(cs_main);
      if (pfMissingInputs)
          *pfMissingInputs = false;
  
      if (!CheckTransaction(tx, state))
          return error("AcceptToMemoryPool: : CheckTransaction failed");
  
      // Coinbase is only valid in a block, not as a loose transaction
      if (tx.IsCoinBase())
          return state.DoS(100, error("AcceptToMemoryPool: : coinbase as individual tx"),
              REJECT_INVALID, "coinbase");
  
      //Coinstake is also only valid in a block, not as a loose transaction
      if (tx.IsCoinStake())
          return state.DoS(100, error("AcceptToMemoryPool: coinstake as individual tx"),
              REJECT_INVALID, "coinstake");
  
      // Rather not work on nonstandard transactions (unless -testnet/-regtest)
      string reason;
      if (Params().RequireStandard() && !IsStandardTx(tx, reason))
          return state.DoS(0,
              error("AcceptToMemoryPool : nonstandard transaction: %s", reason),
              REJECT_NONSTANDARD, reason);
  
      // is it already in the memory pool?
      uint256 hash = tx.GetHash();
      if (pool.exists(hash))
          return false;
  
      // ----------- swiftTX transaction scanning -----------
  
      BOOST_FOREACH (const CTxIn& in, tx.vin) {
          if (mapLockedInputs.count(in.prevout)) {
              if (mapLockedInputs[in.prevout] != tx.GetHash()) {
                  return state.DoS(0,
                      error("AcceptToMemoryPool : conflicts with existing transaction lock: %s", reason),
                      REJECT_INVALID, "tx-lock-conflict");
              }
          }
      }
  
      // Check for conflicts with in-memory transactions
      {
          LOCK(pool.cs); // protect pool.mapNextTx
          for (unsigned int i = 0; i < tx.vin.size(); i++) {
              COutPoint outpoint = tx.vin[i].prevout;
              if (pool.mapNextTx.count(outpoint)) {
                  // Disable replacement feature for now
                  return false;
              }
          }
      }
  
  
      {
          CCoinsView dummy;
          CCoinsViewCache view(&dummy);
  
          CAmount nValueIn = 0;
          {
              LOCK(pool.cs);
              CCoinsViewMemPool viewMemPool(pcoinsTip, pool);
              view.SetBackend(viewMemPool);
  
              // do we already have it?
              if (view.HaveCoins(hash))
                  return false;
  
              // do all inputs exist?
              // Note that this does not check for the presence of actual outputs (see the next check for that),
              // only helps filling in pfMissingInputs (to determine missing vs spent).
              BOOST_FOREACH (const CTxIn txin, tx.vin) {
                  if (!view.HaveCoins(txin.prevout.hash)) {
                      if (pfMissingInputs)
                          *pfMissingInputs = true;
                      return false;
                  }
              }
  
              // are the actual inputs available?
              if (!view.HaveInputs(tx))
                  return state.Invalid(error("AcceptToMemoryPool : inputs already spent"),
                      REJECT_DUPLICATE, "bad-txns-inputs-spent");
  
              // Bring the best block into scope
              view.GetBestBlock();
  
              nValueIn = view.GetValueIn(tx);
  
              // we have all inputs cached now, so switch back to dummy, so we don't need to keep lock on mempool
              view.SetBackend(dummy);
          }
  
          // Check for non-standard pay-to-script-hash in inputs
          if (Params().RequireStandard() && !AreInputsStandard(tx, view))
              return error("AcceptToMemoryPool: : nonstandard transaction input");
  
          // Check that the transaction doesn't have an excessive number of
          // sigops, making it impossible to mine. Since the coinbase transaction
          // itself can contain sigops MAX_TX_SIGOPS is less than
          // MAX_BLOCK_SIGOPS; we still consider this an invalid rather than
          // merely non-standard transaction.
          unsigned int nSigOps = GetLegacySigOpCount(tx);
          nSigOps += GetP2SHSigOpCount(tx, view);
          if (nSigOps > MAX_TX_SIGOPS)
              return state.DoS(0,
                  error("AcceptToMemoryPool : too many sigops %s, %d > %d",
                      hash.ToString(), nSigOps, MAX_TX_SIGOPS),
                  REJECT_NONSTANDARD, "bad-txns-too-many-sigops");
  
          CAmount nValueOut = tx.GetValueOut();
          CAmount nFees = nValueIn - nValueOut;
          double dPriority = view.GetPriority(tx, chainActive.Height());
  
          CTxMemPoolEntry entry(tx, nFees, GetTime(), dPriority, chainActive.Height());
          unsigned int nSize = entry.GetTxSize();
  
          // Don't accept it if it can't get into a block
          // but prioritise dstx and don't check fees for it
          if (mapObfuscationBroadcastTxes.count(hash)) {
              mempool.PrioritiseTransaction(hash, hash.ToString(), 1000, 0.1 * COIN);
          } else if (!ignoreFees) {
              CAmount txMinFee = GetMinRelayFee(tx, nSize, true);
              if (fLimitFree && nFees < txMinFee)
                  return state.DoS(0, error("AcceptToMemoryPool : not enough fees %s, %d < %d",
                                          hash.ToString(), nFees, txMinFee),
                      REJECT_INSUFFICIENTFEE, "insufficient fee");
  
              // Require that free transactions have sufficient priority to be mined in the next block.
              if (GetBoolArg("-relaypriority", true) && nFees < ::minRelayTxFee.GetFee(nSize) && !AllowFree(view.GetPriority(tx, chainActive.Height() + 1))) {
                  return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "insufficient priority");
              }
  
              // Continuously rate-limit free (really, very-low-fee) transactions
              // This mitigates 'penny-flooding' -- sending thousands of free transactions just to
              // be annoying or make others' transactions take longer to confirm.
              if (fLimitFree && nFees < ::minRelayTxFee.GetFee(nSize)) {
                  static CCriticalSection csFreeLimiter;
                  static double dFreeCount;
                  static int64_t nLastTime;
                  int64_t nNow = GetTime();
  
                  LOCK(csFreeLimiter);
  
                  // Use an exponentially decaying ~10-minute window:
                  dFreeCount *= pow(1.0 - 1.0 / 600.0, (double)(nNow - nLastTime));
                  nLastTime = nNow;
                  // -limitfreerelay unit is thousand-bytes-per-minute
                  // At default rate it would take over a month to fill 1GB
                  if (dFreeCount >= GetArg("-limitfreerelay", 15) * 10 * 1000)
                      return state.DoS(0, error("AcceptToMemoryPool : free transaction rejected by rate limiter"),
                          REJECT_INSUFFICIENTFEE, "rate limited free transaction");
                  LogPrint("mempool", "Rate limit dFreeCount: %g => %g\n", dFreeCount, dFreeCount + nSize);
                  dFreeCount += nSize;
              }
          }
  
          if (fRejectInsaneFee && nFees > ::minRelayTxFee.GetFee(nSize) * 10000)
              return error("AcceptToMemoryPool: : insane fees %s, %d > %d",
                  hash.ToString(),
                  nFees, ::minRelayTxFee.GetFee(nSize) * 10000);
  
          // Check against previous transactions
          // This is done last to help prevent CPU exhaustion denial-of-service attacks.
          if (!CheckInputs(tx, state, view, true, STANDARD_SCRIPT_VERIFY_FLAGS, true)) {
              return error("AcceptToMemoryPool: : ConnectInputs failed %s", hash.ToString());
          }
  
          // Check again against just the consensus-critical mandatory script
          // verification flags, in case of bugs in the standard flags that cause
          // transactions to pass as valid when they're actually invalid. For
          // instance the STRICTENC flag was incorrectly allowing certain
          // CHECKSIG NOT scripts to pass, even though they were invalid.
          //
          // There is a similar check in CreateNewBlock() to prevent creating
          // invalid blocks, however allowing such transactions into the mempool
          // can be exploited as a DoS attack.
          if (!CheckInputs(tx, state, view, true, MANDATORY_SCRIPT_VERIFY_FLAGS, true)) {
              return error("AcceptToMemoryPool: : BUG! PLEASE REPORT THIS! ConnectInputs failed against MANDATORY but not STANDARD flags %s", hash.ToString());
          }
  
          // Store transaction in memory
          pool.addUnchecked(hash, entry);
      }
  
      SyncWithWallets(tx, NULL);
  
      return true;
  }
  
  bool AcceptableInputs(CTxMemPool& pool, CValidationState& state, const CTransaction& tx, bool fLimitFree, bool* pfMissingInputs, bool fRejectInsaneFee, bool isDSTX)
  {
      AssertLockHeld(cs_main);
      if (pfMissingInputs)
          *pfMissingInputs = false;
  
      if (!CheckTransaction(tx, state))
          return error("AcceptableInputs: : CheckTransaction failed");
  
      // Coinbase is only valid in a block, not as a loose transaction
      if (tx.IsCoinBase())
          return state.DoS(100, error("AcceptableInputs: : coinbase as individual tx"),
              REJECT_INVALID, "coinbase");
  
      // Rather not work on nonstandard transactions (unless -testnet/-regtest)
      string reason;
      // for any real tx this will be checked on AcceptToMemoryPool anyway
      //    if (Params().RequireStandard() && !IsStandardTx(tx, reason))
      //        return state.DoS(0,
      //                         error("AcceptableInputs : nonstandard transaction: %s", reason),
      //                         REJECT_NONSTANDARD, reason);
  
      // is it already in the memory pool?
      uint256 hash = tx.GetHash();
      if (pool.exists(hash))
          return false;
  
      // ----------- swiftTX transaction scanning -----------
  
      BOOST_FOREACH (const CTxIn& in, tx.vin) {
          if (mapLockedInputs.count(in.prevout)) {
              if (mapLockedInputs[in.prevout] != tx.GetHash()) {
                  return state.DoS(0,
                      error("AcceptableInputs : conflicts with existing transaction lock: %s", reason),
                      REJECT_INVALID, "tx-lock-conflict");
              }
          }
      }
  
      // Check for conflicts with in-memory transactions
      {
          LOCK(pool.cs); // protect pool.mapNextTx
          for (unsigned int i = 0; i < tx.vin.size(); i++) {
              COutPoint outpoint = tx.vin[i].prevout;
              if (pool.mapNextTx.count(outpoint)) {
                  // Disable replacement feature for now
                  return false;
              }
          }
      }
  
  
      {
          CCoinsView dummy;
          CCoinsViewCache view(&dummy);
  
          CAmount nValueIn = 0;
          {
              LOCK(pool.cs);
              CCoinsViewMemPool viewMemPool(pcoinsTip, pool);
              view.SetBackend(viewMemPool);
  
              // do we already have it?
              if (view.HaveCoins(hash))
                  return false;
  
              // do all inputs exist?
              // Note that this does not check for the presence of actual outputs (see the next check for that),
              // only helps filling in pfMissingInputs (to determine missing vs spent).
              BOOST_FOREACH (const CTxIn txin, tx.vin) {
                  if (!view.HaveCoins(txin.prevout.hash)) {
                      if (pfMissingInputs)
                          *pfMissingInputs = true;
                      return false;
                  }
              }
  
              // are the actual inputs available?
              if (!view.HaveInputs(tx))
                  return state.Invalid(error("AcceptableInputs : inputs already spent"),
                      REJECT_DUPLICATE, "bad-txns-inputs-spent");
  
              // Bring the best block into scope
              view.GetBestBlock();
  
              nValueIn = view.GetValueIn(tx);
  
              // we have all inputs cached now, so switch back to dummy, so we don't need to keep lock on mempool
              view.SetBackend(dummy);
          }
  
          // Check for non-standard pay-to-script-hash in inputs
          // for any real tx this will be checked on AcceptToMemoryPool anyway
          //        if (Params().RequireStandard() && !AreInputsStandard(tx, view))
          //            return error("AcceptableInputs: : nonstandard transaction input");
  
          // Check that the transaction doesn't have an excessive number of
          // sigops, making it impossible to mine. Since the coinbase transaction
          // itself can contain sigops MAX_TX_SIGOPS is less than
          // MAX_BLOCK_SIGOPS; we still consider this an invalid rather than
          // merely non-standard transaction.
          unsigned int nSigOps = GetLegacySigOpCount(tx);
          nSigOps += GetP2SHSigOpCount(tx, view);
          if (nSigOps > MAX_TX_SIGOPS)
              return state.DoS(0,
                  error("AcceptableInputs : too many sigops %s, %d > %d",
                      hash.ToString(), nSigOps, MAX_TX_SIGOPS),
                  REJECT_NONSTANDARD, "bad-txns-too-many-sigops");
  
          CAmount nValueOut = tx.GetValueOut();
          CAmount nFees = nValueIn - nValueOut;
          double dPriority = view.GetPriority(tx, chainActive.Height());
  
          CTxMemPoolEntry entry(tx, nFees, GetTime(), dPriority, chainActive.Height());
          unsigned int nSize = entry.GetTxSize();
  
          // Don't accept it if it can't get into a block
          // but prioritise dstx and don't check fees for it
          if (isDSTX) {
              mempool.PrioritiseTransaction(hash, hash.ToString(), 1000, 0.1 * COIN);
          } else { // same as !ignoreFees for AcceptToMemoryPool
              CAmount txMinFee = GetMinRelayFee(tx, nSize, true);
              if (fLimitFree && nFees < txMinFee)
                  return state.DoS(0, error("AcceptableInputs : not enough fees %s, %d < %d",
                                          hash.ToString(), nFees, txMinFee),
                      REJECT_INSUFFICIENTFEE, "insufficient fee");
  
              // Require that free transactions have sufficient priority to be mined in the next block.
              if (GetBoolArg("-relaypriority", true) && nFees < ::minRelayTxFee.GetFee(nSize) && !AllowFree(view.GetPriority(tx, chainActive.Height() + 1))) {
                  return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "insufficient priority");
              }
  
              // Continuously rate-limit free (really, very-low-fee) transactions
              // This mitigates 'penny-flooding' -- sending thousands of free transactions just to
              // be annoying or make others' transactions take longer to confirm.
              if (fLimitFree && nFees < ::minRelayTxFee.GetFee(nSize)) {
                  static CCriticalSection csFreeLimiter;
                  static double dFreeCount;
                  static int64_t nLastTime;
                  int64_t nNow = GetTime();
  
                  LOCK(csFreeLimiter);
  
                  // Use an exponentially decaying ~10-minute window:
                  dFreeCount *= pow(1.0 - 1.0 / 600.0, (double)(nNow - nLastTime));
                  nLastTime = nNow;
                  // -limitfreerelay unit is thousand-bytes-per-minute
                  // At default rate it would take over a month to fill 1GB
                  if (dFreeCount >= GetArg("-limitfreerelay", 15) * 10 * 1000)
                      return state.DoS(0, error("AcceptableInputs : free transaction rejected by rate limiter"),
                          REJECT_INSUFFICIENTFEE, "rate limited free transaction");
                  LogPrint("mempool", "Rate limit dFreeCount: %g => %g\n", dFreeCount, dFreeCount + nSize);
                  dFreeCount += nSize;
              }
          }
  
          if (fRejectInsaneFee && nFees > ::minRelayTxFee.GetFee(nSize) * 10000)
              return error("AcceptableInputs: : insane fees %s, %d > %d",
                  hash.ToString(),
                  nFees, ::minRelayTxFee.GetFee(nSize) * 10000);
  
          // Check against previous transactions
          // This is done last to help prevent CPU exhaustion denial-of-service attacks.
          if (!CheckInputs(tx, state, view, false, STANDARD_SCRIPT_VERIFY_FLAGS, true)) {
              return error("AcceptableInputs: : ConnectInputs failed %s", hash.ToString());
          }
  
          // Check again against just the consensus-critical mandatory script
          // verification flags, in case of bugs in the standard flags that cause
          // transactions to pass as valid when they're actually invalid. For
          // instance the STRICTENC flag was incorrectly allowing certain
          // CHECKSIG NOT scripts to pass, even though they were invalid.
          //
          // There is a similar check in CreateNewBlock() to prevent creating
          // invalid blocks, however allowing such transactions into the mempool
          // can be exploited as a DoS attack.
          // for any real tx this will be checked on AcceptToMemoryPool anyway
          //        if (!CheckInputs(tx, state, view, false, MANDATORY_SCRIPT_VERIFY_FLAGS, true))
          //        {
          //            return error("AcceptableInputs: : BUG! PLEASE REPORT THIS! ConnectInputs failed against MANDATORY but not STANDARD flags %s", hash.ToString());
          //        }
  
          // Store transaction in memory
          // pool.addUnchecked(hash, entry);
      }
  
      // SyncWithWallets(tx, NULL);
  
      return true;
  }
  
  /** Return transaction in tx, and if it was found inside a block, its hash is placed in hashBlock */
  bool GetTransaction(const uint256& hash, CTransaction& txOut, uint256& hashBlock, bool fAllowSlow)
  {
      CBlockIndex* pindexSlow = NULL;
      {
          LOCK(cs_main);
          {
              if (mempool.lookup(hash, txOut)) {
                  return true;
              }
          }
  
          if (fTxIndex) {
              CDiskTxPos postx;
              if (pblocktree->ReadTxIndex(hash, postx)) {
                  CAutoFile file(OpenBlockFile(postx, true), SER_DISK, CLIENT_VERSION);
                  if (file.IsNull())
                      return error("%s: OpenBlockFile failed", __func__);
                  CBlockHeader header;
                  try {
                      file >> header;
                      fseek(file.Get(), postx.nTxOffset, SEEK_CUR);
                      file >> txOut;
                  } catch (std::exception& e) {
                      return error("%s : Deserialize or I/O error - %s", __func__, e.what());
                  }
                  hashBlock = header.GetHash();
                  if (txOut.GetHash() != hash)
                      return error("%s : txid mismatch", __func__);
                  return true;
              }
          }
  
          if (fAllowSlow) { // use coin database to locate block that contains transaction, and scan it
              int nHeight = -1;
              {
                  CCoinsViewCache& view = *pcoinsTip;
                  const CCoins* coins = view.AccessCoins(hash);
                  if (coins)
                      nHeight = coins->nHeight;
              }
              if (nHeight > 0)
                  pindexSlow = chainActive[nHeight];
          }
      }
  
      if (pindexSlow) {
          CBlock block;
          if (ReadBlockFromDisk(block, pindexSlow)) {
              BOOST_FOREACH (const CTransaction& tx, block.vtx) {
                  if (tx.GetHash() == hash) {
                      txOut = tx;
                      hashBlock = pindexSlow->GetBlockHash();
                      return true;
                  }
              }
          }
      }
  
      return false;
  }
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // CBlock and CBlockIndex
  //
  
  bool WriteBlockToDisk(CBlock& block, CDiskBlockPos& pos)
  {
      // Open history file to append
      CAutoFile fileout(OpenBlockFile(pos), SER_DISK, CLIENT_VERSION);
      if (fileout.IsNull())
          return error("WriteBlockToDisk : OpenBlockFile failed");
  
      // Write index header
      unsigned int nSize = fileout.GetSerializeSize(block);
      fileout << FLATDATA(Params().MessageStart()) << nSize;
  
      // Write block
      long fileOutPos = ftell(fileout.Get());
      if (fileOutPos < 0)
          return error("WriteBlockToDisk : ftell failed");
      pos.nPos = (unsigned int)fileOutPos;
      fileout << block;
  
      return true;
  }
  
  bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos)
  {
      block.SetNull();
  
      // Open history file to read
      CAutoFile filein(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION);
      if (filein.IsNull())
          return error("ReadBlockFromDisk : OpenBlockFile failed");
  
      // Read block
      try {
          filein >> block;
      } catch (std::exception& e) {
          return error("%s : Deserialize or I/O error - %s", __func__, e.what());
      }
  
      // Check the header
      if (block.IsProofOfWork()) {
          if (!CheckProofOfWork(block.GetHash(), block.nBits))
              return error("ReadBlockFromDisk : Errors in block header");
      }
  
      return true;
  }
  
  bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex)
  {
      if (!ReadBlockFromDisk(block, pindex->GetBlockPos()))
          return false;
      if (block.GetHash() != pindex->GetBlockHash()) {
          LogPrintf("%s : block=%s index=%s\n", __func__, block.GetHash().ToString().c_str(), pindex->GetBlockHash().ToString().c_str());
          return error("ReadBlockFromDisk(CBlock&, CBlockIndex*) : GetHash() doesn't match index");
      }
      return true;
  }
  
  
  double ConvertBitsToDouble(unsigned int nBits)
  {
      int nShift = (nBits >> 24) & 0xff;
  
      double dDiff =
          (double)0x0000ffff / (double)(nBits & 0x00ffffff);
  
      while (nShift < 29) {
          dDiff *= 256.0;
          nShift++;
      }
      while (nShift > 29) {
          dDiff /= 256.0;
          nShift--;
      }
  
      return dDiff;
  }
  
  int64_t GetBlockValue(int nHeight)
  {
      int64_t nSubsidy = 0;
  
      if (Params().NetworkID() == CBaseChainParams::TESTNET) {
          if (nHeight < 200 && nHeight > 0)
              return 250000 * COIN;
      }
  
      if (nHeight == 0) {
          nSubsidy = 60001 * COIN;
      } else if (nHeight < 86400 && nHeight > 0) {
          nSubsidy = 250 * COIN;
      } else if (nHeight < 151200 && nHeight >= 86400) {
          nSubsidy = 225 * COIN;
      } else if (nHeight <= Params().LAST_POW_BLOCK() && nHeight >= 151200) {
          nSubsidy = 45 * COIN;
      } else if (nHeight <= 302399 && nHeight > Params().LAST_POW_BLOCK()) {
          nSubsidy = 45 * COIN;
      } else if (nHeight <= 345599 && nHeight >= 302400) {
          nSubsidy = 40.5 * COIN;
      } else if (nHeight <= 388799 && nHeight >= 345600) {
          nSubsidy = 36 * COIN;
      } else if (nHeight <= 431999 && nHeight >= 388800) {
          nSubsidy = 31.5 * COIN;
      } else if (nHeight <= 475199 && nHeight >= 432000) {
          nSubsidy = 27 * COIN;
      } else if (nHeight <= 518399 && nHeight >= 475200) {
          nSubsidy = 22.5 * COIN;
      } else if (nHeight <= 561599 && nHeight >= 518400) {
          nSubsidy = 18 * COIN;
      } else if (nHeight <= 604799 && nHeight >= 561600) {
          nSubsidy = 13.5 * COIN;
      } else if (nHeight <= 647999 && nHeight >= 604800) {
          nSubsidy = 9 * COIN;
      } else if (nHeight >= 648000) {
          nSubsidy = 4.5 * COIN;
      } else {
          nSubsidy = 0 * COIN;
      }
      return nSubsidy;
  }
  
  int64_t GetMasternodePayment(int nHeight, int64_t blockValue, int nMasternodeCount)
  {
      int64_t ret = 0;
  
      if (Params().NetworkID() == CBaseChainParams::TESTNET) {
          if (nHeight < 200)
              return 0;
      }
  
      if (nHeight <= 43200) {
          ret = blockValue / 5;
      } else if (nHeight < 86400 && nHeight > 43200) {
          ret = blockValue / (100 / 30);
      } else if (nHeight < 151200 && nHeight >= 86400) {
          ret = 50 * COIN;
      } else if (nHeight <= Params().LAST_POW_BLOCK() && nHeight >= 151200) {
          ret = blockValue / 2;
      } else if (nHeight > Params().LAST_POW_BLOCK()) {
          int64_t nMoneySupply = chainActive.Tip()->nMoneySupply;
          int64_t mNodeCoins = mnodeman.size() * 10000 * COIN;
  
          //if a mn count is inserted into the function we are looking for a specific result for a masternode count
          if(nMasternodeCount)
              mNodeCoins = nMasternodeCount * 10000 * COIN;
  
          if (fDebug)
              LogPrintf("GetMasternodePayment(): moneysupply=%s, nodecoins=%s \n", FormatMoney(nMoneySupply).c_str(),
                  FormatMoney(mNodeCoins).c_str());
  
          if (mNodeCoins == 0) {
              ret = 0;
          } else if (nHeight < 325000) {
              if (mNodeCoins <= (nMoneySupply * .05) && mNodeCoins > 0) {
                  ret = blockValue * .85;
              } else if (mNodeCoins <= (nMoneySupply * .1) && mNodeCoins > (nMoneySupply * .05)) {
                  ret = blockValue * .8;
              } else if (mNodeCoins <= (nMoneySupply * .15) && mNodeCoins > (nMoneySupply * .1)) {
                  ret = blockValue * .75;
              } else if (mNodeCoins <= (nMoneySupply * .2) && mNodeCoins > (nMoneySupply * .15)) {
                  ret = blockValue * .7;
              } else if (mNodeCoins <= (nMoneySupply * .25) && mNodeCoins > (nMoneySupply * .2)) {
                  ret = blockValue * .65;
              } else if (mNodeCoins <= (nMoneySupply * .3) && mNodeCoins > (nMoneySupply * .25)) {
                  ret = blockValue * .6;
              } else if (mNodeCoins <= (nMoneySupply * .35) && mNodeCoins > (nMoneySupply * .3)) {
                  ret = blockValue * .55;
              } else if (mNodeCoins <= (nMoneySupply * .4) && mNodeCoins > (nMoneySupply * .35)) {
                  ret = blockValue * .5;
              } else if (mNodeCoins <= (nMoneySupply * .45) && mNodeCoins > (nMoneySupply * .4)) {
                  ret = blockValue * .45;
              } else if (mNodeCoins <= (nMoneySupply * .5) && mNodeCoins > (nMoneySupply * .45)) {
                  ret = blockValue * .4;
              } else if (mNodeCoins <= (nMoneySupply * .55) && mNodeCoins > (nMoneySupply * .5)) {
                  ret = blockValue * .35;
              } else if (mNodeCoins <= (nMoneySupply * .6) && mNodeCoins > (nMoneySupply * .55)) {
                  ret = blockValue * .3;
              } else if (mNodeCoins <= (nMoneySupply * .65) && mNodeCoins > (nMoneySupply * .6)) {
                  ret = blockValue * .25;
              } else if (mNodeCoins <= (nMoneySupply * .7) && mNodeCoins > (nMoneySupply * .65)) {
                  ret = blockValue * .2;
              } else if (mNodeCoins <= (nMoneySupply * .75) && mNodeCoins > (nMoneySupply * .7)) {
                  ret = blockValue * .15;
              } else {
                  ret = blockValue * .1;
              }
          } else if (nHeight > 325000) {
              if (mNodeCoins <= (nMoneySupply * .01) && mNodeCoins > 0) {
                  ret = blockValue * .90;
              } else if (mNodeCoins <= (nMoneySupply * .02) && mNodeCoins > (nMoneySupply * .01)) {
                  ret = blockValue * .88;
              } else if (mNodeCoins <= (nMoneySupply * .03) && mNodeCoins > (nMoneySupply * .02)) {
                  ret = blockValue * .87;
              } else if (mNodeCoins <= (nMoneySupply * .04) && mNodeCoins > (nMoneySupply * .03)) {
                  ret = blockValue * .86;
              } else if (mNodeCoins <= (nMoneySupply * .05) && mNodeCoins > (nMoneySupply * .04)) {
                  ret = blockValue * .85;
              } else if (mNodeCoins <= (nMoneySupply * .06) && mNodeCoins > (nMoneySupply * .05)) {
                  ret = blockValue * .84;
              } else if (mNodeCoins <= (nMoneySupply * .07) && mNodeCoins > (nMoneySupply * .06)) {
                  ret = blockValue * .83;
              } else if (mNodeCoins <= (nMoneySupply * .08) && mNodeCoins > (nMoneySupply * .07)) {
                  ret = blockValue * .82;
              } else if (mNodeCoins <= (nMoneySupply * .09) && mNodeCoins > (nMoneySupply * .08)) {
                  ret = blockValue * .81;
              } else if (mNodeCoins <= (nMoneySupply * .10) && mNodeCoins > (nMoneySupply * .09)) {
                  ret = blockValue * .80;
              } else if (mNodeCoins <= (nMoneySupply * .11) && mNodeCoins > (nMoneySupply * .10)) {
                  ret = blockValue * .79;
              } else if (mNodeCoins <= (nMoneySupply * .12) && mNodeCoins > (nMoneySupply * .11)) {
                  ret = blockValue * .78;
              } else if (mNodeCoins <= (nMoneySupply * .13) && mNodeCoins > (nMoneySupply * .12)) {
                  ret = blockValue * .77;
              } else if (mNodeCoins <= (nMoneySupply * .14) && mNodeCoins > (nMoneySupply * .13)) {
                  ret = blockValue * .76;
              } else if (mNodeCoins <= (nMoneySupply * .15) && mNodeCoins > (nMoneySupply * .14)) {
                  ret = blockValue * .75;
              } else if (mNodeCoins <= (nMoneySupply * .16) && mNodeCoins > (nMoneySupply * .15)) {
                  ret = blockValue * .74;
              } else if (mNodeCoins <= (nMoneySupply * .17) && mNodeCoins > (nMoneySupply * .16)) {
                  ret = blockValue * .73;
              } else if (mNodeCoins <= (nMoneySupply * .18) && mNodeCoins > (nMoneySupply * .17)) {
                  ret = blockValue * .72;
              } else if (mNodeCoins <= (nMoneySupply * .19) && mNodeCoins > (nMoneySupply * .18)) {
                  ret = blockValue * .71;
              } else if (mNodeCoins <= (nMoneySupply * .20) && mNodeCoins > (nMoneySupply * .19)) {
                  ret = blockValue * .70;
              } else if (mNodeCoins <= (nMoneySupply * .21) && mNodeCoins > (nMoneySupply * .20)) {
                  ret = blockValue * .69;
              } else if (mNodeCoins <= (nMoneySupply * .22) && mNodeCoins > (nMoneySupply * .21)) {
                  ret = blockValue * .68;
              } else if (mNodeCoins <= (nMoneySupply * .23) && mNodeCoins > (nMoneySupply * .22)) {
                  ret = blockValue * .67;
              } else if (mNodeCoins <= (nMoneySupply * .24) && mNodeCoins > (nMoneySupply * .23)) {
                  ret = blockValue * .66;
              } else if (mNodeCoins <= (nMoneySupply * .25) && mNodeCoins > (nMoneySupply * .24)) {
                  ret = blockValue * .65;
              } else if (mNodeCoins <= (nMoneySupply * .26) && mNodeCoins > (nMoneySupply * .25)) {
                  ret = blockValue * .64;
              } else if (mNodeCoins <= (nMoneySupply * .27) && mNodeCoins > (nMoneySupply * .26)) {
                  ret = blockValue * .63;
              } else if (mNodeCoins <= (nMoneySupply * .28) && mNodeCoins > (nMoneySupply * .27)) {
                  ret = blockValue * .62;
              } else if (mNodeCoins <= (nMoneySupply * .29) && mNodeCoins > (nMoneySupply * .28)) {
                  ret = blockValue * .61;
              } else if (mNodeCoins <= (nMoneySupply * .30) && mNodeCoins > (nMoneySupply * .29)) {
                  ret = blockValue * .60;
              } else if (mNodeCoins <= (nMoneySupply * .31) && mNodeCoins > (nMoneySupply * .30)) {
                  ret = blockValue * .59;
              } else if (mNodeCoins <= (nMoneySupply * .32) && mNodeCoins > (nMoneySupply * .31)) {
                  ret = blockValue * .58;
              } else if (mNodeCoins <= (nMoneySupply * .33) && mNodeCoins > (nMoneySupply * .32)) {
                  ret = blockValue * .57;
              } else if (mNodeCoins <= (nMoneySupply * .34) && mNodeCoins > (nMoneySupply * .33)) {
                  ret = blockValue * .56;
              } else if (mNodeCoins <= (nMoneySupply * .35) && mNodeCoins > (nMoneySupply * .34)) {
                  ret = blockValue * .55;
              } else if (mNodeCoins <= (nMoneySupply * .363) && mNodeCoins > (nMoneySupply * .35)) {
                  ret = blockValue * .54;
              } else if (mNodeCoins <= (nMoneySupply * .376) && mNodeCoins > (nMoneySupply * .363)) {
                  ret = blockValue * .53;
              } else if (mNodeCoins <= (nMoneySupply * .389) && mNodeCoins > (nMoneySupply * .376)) {
                  ret = blockValue * .52;
              } else if (mNodeCoins <= (nMoneySupply * .402) && mNodeCoins > (nMoneySupply * .389)) {
                  ret = blockValue * .51;
              } else if (mNodeCoins <= (nMoneySupply * .415) && mNodeCoins > (nMoneySupply * .402)) {
                  ret = blockValue * .50;
              } else if (mNodeCoins <= (nMoneySupply * .428) && mNodeCoins > (nMoneySupply * .415)) {
                  ret = blockValue * .49;
              } else if (mNodeCoins <= (nMoneySupply * .441) && mNodeCoins > (nMoneySupply * .428)) {
                  ret = blockValue * .48;
              } else if (mNodeCoins <= (nMoneySupply * .454) && mNodeCoins > (nMoneySupply * .441)) {
                  ret = blockValue * .47;
              } else if (mNodeCoins <= (nMoneySupply * .467) && mNodeCoins > (nMoneySupply * .454)) {
                  ret = blockValue * .46;
              } else if (mNodeCoins <= (nMoneySupply * .48) && mNodeCoins > (nMoneySupply * .467)) {
                  ret = blockValue * .45;
              } else if (mNodeCoins <= (nMoneySupply * .493) && mNodeCoins > (nMoneySupply * .48)) {
                  ret = blockValue * .44;
              } else if (mNodeCoins <= (nMoneySupply * .506) && mNodeCoins > (nMoneySupply * .493)) {
                  ret = blockValue * .43;
              } else if (mNodeCoins <= (nMoneySupply * .519) && mNodeCoins > (nMoneySupply * .506)) {
                  ret = blockValue * .42;
              } else if (mNodeCoins <= (nMoneySupply * .532) && mNodeCoins > (nMoneySupply * .519)) {
                  ret = blockValue * .41;
              } else if (mNodeCoins <= (nMoneySupply * .545) && mNodeCoins > (nMoneySupply * .532)) {
                  ret = blockValue * .40;
              } else if (mNodeCoins <= (nMoneySupply * .558) && mNodeCoins > (nMoneySupply * .545)) {
                  ret = blockValue * .39;
              } else if (mNodeCoins <= (nMoneySupply * .571) && mNodeCoins > (nMoneySupply * .558)) {
                  ret = blockValue * .38;
              } else if (mNodeCoins <= (nMoneySupply * .584) && mNodeCoins > (nMoneySupply * .571)) {
                  ret = blockValue * .37;
              } else if (mNodeCoins <= (nMoneySupply * .597) && mNodeCoins > (nMoneySupply * .584)) {
                  ret = blockValue * .36;
              } else if (mNodeCoins <= (nMoneySupply * .61) && mNodeCoins > (nMoneySupply * .597)) {
                  ret = blockValue * .35;
              } else if (mNodeCoins <= (nMoneySupply * .623) && mNodeCoins > (nMoneySupply * .61)) {
                  ret = blockValue * .34;
              } else if (mNodeCoins <= (nMoneySupply * .636) && mNodeCoins > (nMoneySupply * .623)) {
                  ret = blockValue * .33;
              } else if (mNodeCoins <= (nMoneySupply * .649) && mNodeCoins > (nMoneySupply * .636)) {
                  ret = blockValue * .32;
              } else if (mNodeCoins <= (nMoneySupply * .662) && mNodeCoins > (nMoneySupply * .649)) {
                  ret = blockValue * .31;
              } else if (mNodeCoins <= (nMoneySupply * .675) && mNodeCoins > (nMoneySupply * .662)) {
                  ret = blockValue * .30;
              } else if (mNodeCoins <= (nMoneySupply * .688) && mNodeCoins > (nMoneySupply * .675)) {
                  ret = blockValue * .29;
              } else if (mNodeCoins <= (nMoneySupply * .701) && mNodeCoins > (nMoneySupply * .688)) {
                  ret = blockValue * .28;
              } else if (mNodeCoins <= (nMoneySupply * .714) && mNodeCoins > (nMoneySupply * .701)) {
                  ret = blockValue * .27;
              } else if (mNodeCoins <= (nMoneySupply * .727) && mNodeCoins > (nMoneySupply * .714)) {
                  ret = blockValue * .26;
              } else if (mNodeCoins <= (nMoneySupply * .74) && mNodeCoins > (nMoneySupply * .727)) {
                  ret = blockValue * .25;
              } else if (mNodeCoins <= (nMoneySupply * .753) && mNodeCoins > (nMoneySupply * .74)) {
                  ret = blockValue * .24;
              } else if (mNodeCoins <= (nMoneySupply * .766) && mNodeCoins > (nMoneySupply * .753)) {
                  ret = blockValue * .23;
              } else if (mNodeCoins <= (nMoneySupply * .779) && mNodeCoins > (nMoneySupply * .766)) {
                  ret = blockValue * .22;
              } else if (mNodeCoins <= (nMoneySupply * .792) && mNodeCoins > (nMoneySupply * .779)) {
                  ret = blockValue * .21;
              } else if (mNodeCoins <= (nMoneySupply * .805) && mNodeCoins > (nMoneySupply * .792)) {
                  ret = blockValue * .20;
              } else if (mNodeCoins <= (nMoneySupply * .818) && mNodeCoins > (nMoneySupply * .805)) {
                  ret = blockValue * .19;
              } else if (mNodeCoins <= (nMoneySupply * .831) && mNodeCoins > (nMoneySupply * .818)) {
                  ret = blockValue * .18;
              } else if (mNodeCoins <= (nMoneySupply * .844) && mNodeCoins > (nMoneySupply * .831)) {
                  ret = blockValue * .17;
              } else if (mNodeCoins <= (nMoneySupply * .857) && mNodeCoins > (nMoneySupply * .844)) {
                  ret = blockValue * .16;
              } else if (mNodeCoins <= (nMoneySupply * .87) && mNodeCoins > (nMoneySupply * .857)) {
                  ret = blockValue * .15;
              } else if (mNodeCoins <= (nMoneySupply * .883) && mNodeCoins > (nMoneySupply * .87)) {
                  ret = blockValue * .14;
              } else if (mNodeCoins <= (nMoneySupply * .896) && mNodeCoins > (nMoneySupply * .883)) {
                  ret = blockValue * .13;
              } else if (mNodeCoins <= (nMoneySupply * .909) && mNodeCoins > (nMoneySupply * .896)) {
                  ret = blockValue * .12;
              } else if (mNodeCoins <= (nMoneySupply * .922) && mNodeCoins > (nMoneySupply * .909)) {
                  ret = blockValue * .11;
              } else if (mNodeCoins <= (nMoneySupply * .935) && mNodeCoins > (nMoneySupply * .922)) {
                  ret = blockValue * .10;
              } else if (mNodeCoins <= (nMoneySupply * .945) && mNodeCoins > (nMoneySupply * .935)) {
                  ret = blockValue * .09;
              } else if (mNodeCoins <= (nMoneySupply * .961) && mNodeCoins > (nMoneySupply * .945)) {
                  ret = blockValue * .08;
              } else if (mNodeCoins <= (nMoneySupply * .974) && mNodeCoins > (nMoneySupply * .961)) {
                  ret = blockValue * .07;
              } else if (mNodeCoins <= (nMoneySupply * .987) && mNodeCoins > (nMoneySupply * .974)) {
                  ret = blockValue * .06;
              } else if (mNodeCoins <= (nMoneySupply * .99) && mNodeCoins > (nMoneySupply * .987)) {
                  ret = blockValue * .05;
              } else {
                  ret = blockValue * .01;
              }
          }
      }
  
      return ret;
  }
  
  bool IsInitialBlockDownload()
  {
      LOCK(cs_main);
      if (fImporting || fReindex || chainActive.Height() < Checkpoints::GetTotalBlocksEstimate())
          return true;
      static bool lockIBDState = false;
      if (lockIBDState)
          return false;
      bool state = (chainActive.Height() < pindexBestHeader->nHeight - 24 * 6 ||
                    pindexBestHeader->GetBlockTime() < GetTime() - 6 * 60 * 60); // ~144 blocks behind -> 2 x fork detection time
      if (!state)
          lockIBDState = true;
      return state;
  }
  
  bool fLargeWorkForkFound = false;
  bool fLargeWorkInvalidChainFound = false;
  CBlockIndex *pindexBestForkTip = NULL, *pindexBestForkBase = NULL;
  
  void CheckForkWarningConditions()
  {
      AssertLockHeld(cs_main);
      // Before we get past initial download, we cannot reliably alert about forks
      // (we assume we don't get stuck on a fork before the last checkpoint)
      if (IsInitialBlockDownload())
          return;
  
      // If our best fork is no longer within 72 blocks (+/- 3 hours if no one mines it)
      // of our head, drop it
      if (pindexBestForkTip && chainActive.Height() - pindexBestForkTip->nHeight >= 72)
          pindexBestForkTip = NULL;
  
      if (pindexBestForkTip || (pindexBestInvalid && pindexBestInvalid->nChainWork > chainActive.Tip()->nChainWork + (GetBlockProof(*chainActive.Tip()) * 6))) {
          if (!fLargeWorkForkFound && pindexBestForkBase) {
              if (pindexBestForkBase->phashBlock) {
                  std::string warning = std::string("'Warning: Large-work fork detected, forking after block ") +
                                        pindexBestForkBase->phashBlock->ToString() + std::string("'");
                  CAlert::Notify(warning, true);
              }
          }
          if (pindexBestForkTip && pindexBestForkBase) {
              if (pindexBestForkBase->phashBlock) {
                  LogPrintf("CheckForkWarningConditions: Warning: Large valid fork found\n  forking the chain at height %d (%s)\n  lasting to height %d (%s).\nChain state database corruption likely.\n",
                      pindexBestForkBase->nHeight, pindexBestForkBase->phashBlock->ToString(),
                      pindexBestForkTip->nHeight, pindexBestForkTip->phashBlock->ToString());
                  fLargeWorkForkFound = true;
              }
          } else {
              LogPrintf("CheckForkWarningConditions: Warning: Found invalid chain at least ~6 blocks longer than our best chain.\nChain state database corruption likely.\n");
              fLargeWorkInvalidChainFound = true;
          }
      } else {
          fLargeWorkForkFound = false;
          fLargeWorkInvalidChainFound = false;
      }
  }
  
  void CheckForkWarningConditionsOnNewFork(CBlockIndex* pindexNewForkTip)
  {
      AssertLockHeld(cs_main);
      // If we are on a fork that is sufficiently large, set a warning flag
      CBlockIndex* pfork = pindexNewForkTip;
      CBlockIndex* plonger = chainActive.Tip();
      while (pfork && pfork != plonger) {
          while (plonger && plonger->nHeight > pfork->nHeight)
              plonger = plonger->pprev;
          if (pfork == plonger)
              break;
          pfork = pfork->pprev;
      }
  
      // We define a condition which we should warn the user about as a fork of at least 7 blocks
      // who's tip is within 72 blocks (+/- 3 hours if no one mines it) of ours
      // or a chain that is entirely longer than ours and invalid (note that this should be detected by both)
      // We use 7 blocks rather arbitrarily as it represents just under 10% of sustained network
      // hash rate operating on the fork.
      // We define it this way because it allows us to only store the highest fork tip (+ base) which meets
      // the 7-block condition and from this always have the most-likely-to-cause-warning fork
      if (pfork && (!pindexBestForkTip || (pindexBestForkTip && pindexNewForkTip->nHeight > pindexBestForkTip->nHeight)) &&
          pindexNewForkTip->nChainWork - pfork->nChainWork > (GetBlockProof(*pfork) * 7) &&
          chainActive.Height() - pindexNewForkTip->nHeight < 72) {
          pindexBestForkTip = pindexNewForkTip;
          pindexBestForkBase = pfork;
      }
  
      CheckForkWarningConditions();
  }
  
  // Requires cs_main.
  void Misbehaving(NodeId pnode, int howmuch)
  {
      if (howmuch == 0)
          return;
  
      CNodeState* state = State(pnode);
      if (state == NULL)
          return;
  
      state->nMisbehavior += howmuch;
      int banscore = GetArg("-banscore", 100);
      if (state->nMisbehavior >= banscore && state->nMisbehavior - howmuch < banscore) {
          LogPrintf("Misbehaving: %s (%d -> %d) BAN THRESHOLD EXCEEDED\n", state->name, state->nMisbehavior - howmuch, state->nMisbehavior);
          state->fShouldBan = true;
      } else
          LogPrintf("Misbehaving: %s (%d -> %d)\n", state->name, state->nMisbehavior - howmuch, state->nMisbehavior);
  }
  
  void static InvalidChainFound(CBlockIndex* pindexNew)
  {
      if (!pindexBestInvalid || pindexNew->nChainWork > pindexBestInvalid->nChainWork)
          pindexBestInvalid = pindexNew;
  
      LogPrintf("InvalidChainFound: invalid block=%s  height=%d  log2_work=%.8g  date=%s\n",
          pindexNew->GetBlockHash().ToString(), pindexNew->nHeight,
          log(pindexNew->nChainWork.getdouble()) / log(2.0), DateTimeStrFormat("%Y-%m-%d %H:%M:%S",
                                                                 pindexNew->GetBlockTime()));
      LogPrintf("InvalidChainFound:  current best=%s  height=%d  log2_work=%.8g  date=%s\n",
          chainActive.Tip()->GetBlockHash().ToString(), chainActive.Height(), log(chainActive.Tip()->nChainWork.getdouble()) / log(2.0),
          DateTimeStrFormat("%Y-%m-%d %H:%M:%S", chainActive.Tip()->GetBlockTime()));
      CheckForkWarningConditions();
  }
  
  void static InvalidBlockFound(CBlockIndex* pindex, const CValidationState& state)
  {
      int nDoS = 0;
      if (state.IsInvalid(nDoS)) {
          std::map<uint256, NodeId>::iterator it = mapBlockSource.find(pindex->GetBlockHash());
          if (it != mapBlockSource.end() && State(it->second)) {
              CBlockReject reject = {state.GetRejectCode(), state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), pindex->GetBlockHash()};
              State(it->second)->rejects.push_back(reject);
              if (nDoS > 0)
                  Misbehaving(it->second, nDoS);
          }
      }
      if (!state.CorruptionPossible()) {
          pindex->nStatus |= BLOCK_FAILED_VALID;
          setDirtyBlockIndex.insert(pindex);
          setBlockIndexCandidates.erase(pindex);
          InvalidChainFound(pindex);
      }
  }
  
  void UpdateCoins(const CTransaction& tx, CValidationState& state, CCoinsViewCache& inputs, CTxUndo& txundo, int nHeight)
  {
      // mark inputs spent
      if (!tx.IsCoinBase()) {
          txundo.vprevout.reserve(tx.vin.size());
          BOOST_FOREACH (const CTxIn& txin, tx.vin) {
              txundo.vprevout.push_back(CTxInUndo());
              bool ret = inputs.ModifyCoins(txin.prevout.hash)->Spend(txin.prevout, txundo.vprevout.back());
              assert(ret);
          }
      }
  
      // add outputs
      inputs.ModifyCoins(tx.GetHash())->FromTx(tx, nHeight);
  }
  
  bool CScriptCheck::operator()()
  {
      const CScript& scriptSig = ptxTo->vin[nIn].scriptSig;
      if (!VerifyScript(scriptSig, scriptPubKey, nFlags, CachingTransactionSignatureChecker(ptxTo, nIn, cacheStore), &error)) {
          return ::error("CScriptCheck(): %s:%d VerifySignature failed: %s", ptxTo->GetHash().ToString(), nIn, ScriptErrorString(error));
      }
      return true;
  }
  
  bool CheckInputs(const CTransaction& tx, CValidationState& state, const CCoinsViewCache& inputs, bool fScriptChecks, unsigned int flags, bool cacheStore, std::vector<CScriptCheck>* pvChecks)
  {
      if (!tx.IsCoinBase()) {
          if (pvChecks)
              pvChecks->reserve(tx.vin.size());
  
          // This doesn't trigger the DoS code on purpose; if it did, it would make it easier
          // for an attacker to attempt to split the network.
          if (!inputs.HaveInputs(tx))
              return state.Invalid(error("CheckInputs() : %s inputs unavailable", tx.GetHash().ToString()));
  
          // While checking, GetBestBlock() refers to the parent block.
          // This is also true for mempool checks.
          CBlockIndex* pindexPrev = mapBlockIndex.find(inputs.GetBestBlock())->second;
          int nSpendHeight = pindexPrev->nHeight + 1;
          CAmount nValueIn = 0;
          CAmount nFees = 0;
          for (unsigned int i = 0; i < tx.vin.size(); i++) {
              const COutPoint& prevout = tx.vin[i].prevout;
              const CCoins* coins = inputs.AccessCoins(prevout.hash);
              assert(coins);
  
              // If prev is coinbase, check that it's matured
              if (coins->IsCoinBase() || coins->IsCoinStake()) {
                  if (nSpendHeight - coins->nHeight < Params().COINBASE_MATURITY())
                      return state.Invalid(
                          error("CheckInputs() : tried to spend coinbase at depth %d, coinstake=%d", nSpendHeight - coins->nHeight, coins->IsCoinStake()),
                          REJECT_INVALID, "bad-txns-premature-spend-of-coinbase");
              }
  
              // Check for negative or overflow input values
              nValueIn += coins->vout[prevout.n].nValue;
              if (!MoneyRange(coins->vout[prevout.n].nValue) || !MoneyRange(nValueIn))
                  return state.DoS(100, error("CheckInputs() : txin values out of range"),
                      REJECT_INVALID, "bad-txns-inputvalues-outofrange");
          }
  
          if (!tx.IsCoinStake()) {
              if (nValueIn < tx.GetValueOut())
                  return state.DoS(100, error("CheckInputs() : %s value in (%s) < value out (%s)",
                                            tx.GetHash().ToString(), FormatMoney(nValueIn), FormatMoney(tx.GetValueOut())),
                      REJECT_INVALID, "bad-txns-in-belowout");
  
              // Tally transaction fees
              CAmount nTxFee = nValueIn - tx.GetValueOut();
              if (nTxFee < 0)
                  return state.DoS(100, error("CheckInputs() : %s nTxFee < 0", tx.GetHash().ToString()),
                      REJECT_INVALID, "bad-txns-fee-negative");
              nFees += nTxFee;
              if (!MoneyRange(nFees))
                  return state.DoS(100, error("CheckInputs() : nFees out of range"),
                      REJECT_INVALID, "bad-txns-fee-outofrange");
          }
          // The first loop above does all the inexpensive checks.
          // Only if ALL inputs pass do we perform expensive ECDSA signature checks.
          // Helps prevent CPU exhaustion attacks.
  
          // Skip ECDSA signature verification when connecting blocks
          // before the last block chain checkpoint. This is safe because block merkle hashes are
          // still computed and checked, and any change will be caught at the next checkpoint.
          if (fScriptChecks) {
              for (unsigned int i = 0; i < tx.vin.size(); i++) {
                  const COutPoint& prevout = tx.vin[i].prevout;
                  const CCoins* coins = inputs.AccessCoins(prevout.hash);
                  assert(coins);
  
                  // Verify signature
                  CScriptCheck check(*coins, tx, i, flags, cacheStore);
                  if (pvChecks) {
                      pvChecks->push_back(CScriptCheck());
                      check.swap(pvChecks->back());
                  } else if (!check()) {
                      if (flags & STANDARD_NOT_MANDATORY_VERIFY_FLAGS) {
                          // Check whether the failure was caused by a
                          // non-mandatory script verification check, such as
                          // non-standard DER encodings or non-null dummy
                          // arguments; if so, don't trigger DoS protection to
                          // avoid splitting the network between upgraded and
                          // non-upgraded nodes.
                          CScriptCheck check(*coins, tx, i,
                              flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, cacheStore);
                          if (check())
                              return state.Invalid(false, REJECT_NONSTANDARD, strprintf("non-mandatory-script-verify-flag (%s)", ScriptErrorString(check.GetScriptError())));
                      }
                      // Failures of other flags indicate a transaction that is
                      // invalid in new blocks, e.g. a invalid P2SH. We DoS ban
                      // such nodes as they are not following the protocol. That
                      // said during an upgrade careful thought should be taken
                      // as to the correct behavior - we may want to continue
                      // peering with non-upgraded nodes even after a soft-fork
                      // super-majority vote has passed.
                      return state.DoS(100, false, REJECT_INVALID, strprintf("mandatory-script-verify-flag-failed (%s)", ScriptErrorString(check.GetScriptError())));
                  }
              }
          }
      }
  
      return true;
  }
  
  bool DisconnectBlock(CBlock& block, CValidationState& state, CBlockIndex* pindex, CCoinsViewCache& view, bool* pfClean)
  {
      assert(pindex->GetBlockHash() == view.GetBestBlock());
  
      if (pfClean)
          *pfClean = false;
  
      bool fClean = true;
  
      CBlockUndo blockUndo;
      CDiskBlockPos pos = pindex->GetUndoPos();
      if (pos.IsNull())
          return error("DisconnectBlock() : no undo data available");
      if (!blockUndo.ReadFromDisk(pos, pindex->pprev->GetBlockHash()))
          return error("DisconnectBlock() : failure reading undo data");
  
      if (blockUndo.vtxundo.size() + 1 != block.vtx.size())
          return error("DisconnectBlock() : block and undo data inconsistent");
  
      // undo transactions in reverse order
      for (int i = block.vtx.size() - 1; i >= 0; i--) {
          const CTransaction& tx = block.vtx[i];
          uint256 hash = tx.GetHash();
  
          // Check that all outputs are available and match the outputs in the block itself
          // exactly. Note that transactions with only provably unspendable outputs won't
          // have outputs available even in the block itself, so we handle that case
          // specially with outsEmpty.
          {
              CCoins outsEmpty;
              CCoinsModifier outs = view.ModifyCoins(hash);
              outs->ClearUnspendable();
  
              CCoins outsBlock(tx, pindex->nHeight);
              // The CCoins serialization does not serialize negative numbers.
              // No network rules currently depend on the version here, so an inconsistency is harmless
              // but it must be corrected before txout nversion ever influences a network rule.
              if (outsBlock.nVersion < 0)
                  outs->nVersion = outsBlock.nVersion;
              if (*outs != outsBlock)
                  fClean = fClean && error("DisconnectBlock() : added transaction mismatch? database corrupted");
  
              // remove outputs
              outs->Clear();
          }
  
          // restore inputs
          if (i > 0) { // not coinbases
              const CTxUndo& txundo = blockUndo.vtxundo[i - 1];
              if (txundo.vprevout.size() != tx.vin.size())
                  return error("DisconnectBlock() : transaction and undo data inconsistent - txundo.vprevout.siz=%d tx.vin.siz=%d", txundo.vprevout.size(), tx.vin.size());
              for (unsigned int j = tx.vin.size(); j-- > 0;) {
                  const COutPoint& out = tx.vin[j].prevout;
                  const CTxInUndo& undo = txundo.vprevout[j];
                  CCoinsModifier coins = view.ModifyCoins(out.hash);
                  if (undo.nHeight != 0) {
                      // undo data contains height: this is the last output of the prevout tx being spent
                      if (!coins->IsPruned())
                          fClean = fClean && error("DisconnectBlock() : undo data overwriting existing transaction");
                      coins->Clear();
                      coins->fCoinBase = undo.fCoinBase;
                      coins->nHeight = undo.nHeight;
                      coins->nVersion = undo.nVersion;
                  } else {
                      if (coins->IsPruned())
                          fClean = fClean && error("DisconnectBlock() : undo data adding output to missing transaction");
                  }
                  if (coins->IsAvailable(out.n))
                      fClean = fClean && error("DisconnectBlock() : undo data overwriting existing output");
                  if (coins->vout.size() < out.n + 1)
                      coins->vout.resize(out.n + 1);
                  coins->vout[out.n] = undo.txout;
              }
          }
      }
  
      // move best block pointer to prevout block
      view.SetBestBlock(pindex->pprev->GetBlockHash());
  
      if (pfClean) {
          *pfClean = fClean;
          return true;
      } else {
          return fClean;
      }
  }
  
  void static FlushBlockFile(bool fFinalize = false)
  {
      LOCK(cs_LastBlockFile);
  
      CDiskBlockPos posOld(nLastBlockFile, 0);
  
      FILE* fileOld = OpenBlockFile(posOld);
      if (fileOld) {
          if (fFinalize)
              TruncateFile(fileOld, vinfoBlockFile[nLastBlockFile].nSize);
          FileCommit(fileOld);
          fclose(fileOld);
      }
  
      fileOld = OpenUndoFile(posOld);
      if (fileOld) {
          if (fFinalize)
              TruncateFile(fileOld, vinfoBlockFile[nLastBlockFile].nUndoSize);
          FileCommit(fileOld);
          fclose(fileOld);
      }
  }
  
  bool FindUndoPos(CValidationState& state, int nFile, CDiskBlockPos& pos, unsigned int nAddSize);
  
  static CCheckQueue<CScriptCheck> scriptcheckqueue(128);
  
  void ThreadScriptCheck()
  {
      RenameThread("clonecoin-scriptch");
      scriptcheckqueue.Thread();
  }
  
  static int64_t nTimeVerify = 0;
  static int64_t nTimeConnect = 0;
  static int64_t nTimeIndex = 0;
  static int64_t nTimeCallbacks = 0;
  static int64_t nTimeTotal = 0;
  
  bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pindex, CCoinsViewCache& view, bool fJustCheck)
  {
      AssertLockHeld(cs_main);
      // Check it again in case a previous version let a bad block in
      if (!CheckBlock(block, state, !fJustCheck, !fJustCheck))
          return false;
  
      // verify that the view's current state corresponds to the previous block
      uint256 hashPrevBlock = pindex->pprev == NULL ? uint256(0) : pindex->pprev->GetBlockHash();
      if (hashPrevBlock != view.GetBestBlock())
          LogPrintf("%s: hashPrev=%s view=%s\n", __func__, hashPrevBlock.ToString().c_str(), view.GetBestBlock().ToString().c_str());
      assert(hashPrevBlock == view.GetBestBlock());
  
      // Special case for the genesis block, skipping connection of its transactions
      // (its coinbase is unspendable)
      if (block.GetHash() == Params().HashGenesisBlock()) {
          view.SetBestBlock(pindex->GetBlockHash());
          return true;
      }
  
      if (pindex->nHeight <= Params().LAST_POW_BLOCK() && block.IsProofOfStake())
          return state.DoS(100, error("ConnectBlock() : PoS period not active"),
              REJECT_INVALID, "PoS-early");
  
      if (pindex->nHeight > Params().LAST_POW_BLOCK() && block.IsProofOfWork())
          return state.DoS(100, error("ConnectBlock() : PoW period ended"),
              REJECT_INVALID, "PoW-ended");
  
      bool fScriptChecks = pindex->nHeight >= Checkpoints::GetTotalBlocksEstimate();
  
      // Do not allow blocks that contain transactions which 'overwrite' older transactions,
      // unless those are already completely spent.
      // If such overwrites are allowed, coinbases and transactions depending upon those
      // can be duplicated to remove the ability to spend the first instance -- even after
      // being sent to another address.
      // See BIP30 and http://r6.ca/blog/20120206T005236Z.html for more information.
      // This logic is not necessary for memory pool transactions, as AcceptToMemoryPool
      // already refuses previously-known transaction ids entirely.
      // This rule was originally applied all blocks whose timestamp was after March 15, 2012, 0:00 UTC.
      // Now that the whole chain is irreversibly beyond that time it is applied to all blocks except the
      // two in the chain that violate it. This prevents exploiting the issue against nodes in their
      // initial block download.
      bool fEnforceBIP30 = (!pindex->phashBlock) || // Enforce on CreateNewBlock invocations which don't have a hash.
                           !((pindex->nHeight == 91842 && pindex->GetBlockHash() == uint256("0x00000000000a4d0a398161ffc163c503763b1f4360639393e0e4c8e300e0caec")) ||
                               (pindex->nHeight == 91880 && pindex->GetBlockHash() == uint256("0x00000000000743f190a18c5577a3c2d2a1f610ae9601ac046a38084ccb7cd721")));
      if (fEnforceBIP30) {
          BOOST_FOREACH (const CTransaction& tx, block.vtx) {
              const CCoins* coins = view.AccessCoins(tx.GetHash());
              if (coins && !coins->IsPruned())
                  return state.DoS(100, error("ConnectBlock() : tried to overwrite transaction"),
                      REJECT_INVALID, "bad-txns-BIP30");
          }
      }
  
      // BIP16 didn't become active until Apr 1 2012
      int64_t nBIP16SwitchTime = 1333238400;
      bool fStrictPayToScriptHash = (pindex->GetBlockTime() >= nBIP16SwitchTime);
  
      unsigned int flags = fStrictPayToScriptHash ? SCRIPT_VERIFY_P2SH : SCRIPT_VERIFY_NONE;
  
      // Start enforcing the DERSIG (BIP66) rules, for block.nVersion=3 blocks, when 75% of the network has upgraded:
      if (block.nVersion >= 3 && CBlockIndex::IsSuperMajority(3, pindex->pprev, Params().EnforceBlockUpgradeMajority())) {
          flags |= SCRIPT_VERIFY_DERSIG;
      }
  
      CBlockUndo blockundo;
  
      CCheckQueueControl<CScriptCheck> control(fScriptChecks && nScriptCheckThreads ? &scriptcheckqueue : NULL);
  
      int64_t nTimeStart = GetTimeMicros();
      CAmount nFees = 0;
      int nInputs = 0;
      unsigned int nSigOps = 0;
      CDiskTxPos pos(pindex->GetBlockPos(), GetSizeOfCompactSize(block.vtx.size()));
      std::vector<std::pair<uint256, CDiskTxPos> > vPos;
      vPos.reserve(block.vtx.size());
      blockundo.vtxundo.reserve(block.vtx.size() - 1);
      int64_t nValueOut = 0;
      int64_t nValueIn = 0;
      for (unsigned int i = 0; i < block.vtx.size(); i++) {
          const CTransaction& tx = block.vtx[i];
  
          nInputs += tx.vin.size();
          nSigOps += GetLegacySigOpCount(tx);
          if (nSigOps > MAX_BLOCK_SIGOPS)
              return state.DoS(100, error("ConnectBlock() : too many sigops"),
                  REJECT_INVALID, "bad-blk-sigops");
  
          if (!tx.IsCoinBase()) {
              if (!view.HaveInputs(tx))
                  return state.DoS(100, error("ConnectBlock() : inputs missing/spent"),
                      REJECT_INVALID, "bad-txns-inputs-missingorspent");
  
              if (fStrictPayToScriptHash) {
                  // Add in sigops done by pay-to-script-hash inputs;
                  // this is to prevent a "rogue miner" from creating
                  // an incredibly-expensive-to-validate block.
                  nSigOps += GetP2SHSigOpCount(tx, view);
                  if (nSigOps > MAX_BLOCK_SIGOPS)
                      return state.DoS(100, error("ConnectBlock() : too many sigops"),
                          REJECT_INVALID, "bad-blk-sigops");
              }
  
              nFees += view.GetValueIn(tx) - tx.GetValueOut();
              nValueIn += view.GetValueIn(tx);
  
              std::vector<CScriptCheck> vChecks;
              if (!CheckInputs(tx, state, view, fScriptChecks, flags, false, nScriptCheckThreads ? &vChecks : NULL))
                  return false;
              control.Add(vChecks);
          }
          nValueOut += tx.GetValueOut();
  
          CTxUndo undoDummy;
          if (i > 0) {
              blockundo.vtxundo.push_back(CTxUndo());
          }
          UpdateCoins(tx, state, view, i == 0 ? undoDummy : blockundo.vtxundo.back(), pindex->nHeight);
  
          vPos.push_back(std::make_pair(tx.GetHash(), pos));
          pos.nTxOffset += ::GetSerializeSize(tx, SER_DISK, CLIENT_VERSION);
      }
  
      // ppcoin: track money supply and mint amount info
      pindex->nMint = nValueOut - nValueIn + nFees;
      pindex->nMoneySupply = (pindex->pprev ? pindex->pprev->nMoneySupply : 0) + nValueOut - nValueIn;
  
      if (!pblocktree->WriteBlockIndex(CDiskBlockIndex(pindex)))
          return error("Connect() : WriteBlockIndex for pindex failed");
  
      int64_t nTime1 = GetTimeMicros();
      nTimeConnect += nTime1 - nTimeStart;
      LogPrint("bench", "      - Connect %u transactions: %.2fms (%.3fms/tx, %.3fms/txin) [%.2fs]\n", (unsigned)block.vtx.size(), 0.001 * (nTime1 - nTimeStart), 0.001 * (nTime1 - nTimeStart) / block.vtx.size(), nInputs <= 1 ? 0 : 0.001 * (nTime1 - nTimeStart) / (nInputs - 1), nTimeConnect * 0.000001);
  
      if (!IsInitialBlockDownload() && !IsBlockValueValid(block, GetBlockValue(pindex->pprev->nHeight))) {
          return state.DoS(100,
              error("ConnectBlock() : reward pays too much (actual=%d vs limit=%d)",
                  block.vtx[0].GetValueOut(), GetBlockValue(pindex->pprev->nHeight)),
              REJECT_INVALID, "bad-cb-amount");
      }
  
      if (!control.Wait())
          return state.DoS(100, false);
      int64_t nTime2 = GetTimeMicros();
      nTimeVerify += nTime2 - nTimeStart;
      LogPrint("bench", "    - Verify %u txins: %.2fms (%.3fms/txin) [%.2fs]\n", nInputs - 1, 0.001 * (nTime2 - nTimeStart), nInputs <= 1 ? 0 : 0.001 * (nTime2 - nTimeStart) / (nInputs - 1), nTimeVerify * 0.000001);
  
      if (fJustCheck)
          return true;
  
      // Write undo information to disk
      if (pindex->GetUndoPos().IsNull() || !pindex->IsValid(BLOCK_VALID_SCRIPTS)) {
          if (pindex->GetUndoPos().IsNull()) {
              CDiskBlockPos pos;
              if (!FindUndoPos(state, pindex->nFile, pos, ::GetSerializeSize(blockundo, SER_DISK, CLIENT_VERSION) + 40))
                  return error("ConnectBlock() : FindUndoPos failed");
              if (!blockundo.WriteToDisk(pos, pindex->pprev->GetBlockHash()))
                  return state.Abort("Failed to write undo data");
  
              // update nUndoPos in block index
              pindex->nUndoPos = pos.nPos;
              pindex->nStatus |= BLOCK_HAVE_UNDO;
          }
  
          pindex->RaiseValidity(BLOCK_VALID_SCRIPTS);
          setDirtyBlockIndex.insert(pindex);
      }
  
      if (fTxIndex)
          if (!pblocktree->WriteTxIndex(vPos))
              return state.Abort("Failed to write transaction index");
  
      // add this block to the view's block chain
      view.SetBestBlock(pindex->GetBlockHash());
  
      int64_t nTime3 = GetTimeMicros();
      nTimeIndex += nTime3 - nTime2;
      LogPrint("bench", "    - Index writing: %.2fms [%.2fs]\n", 0.001 * (nTime3 - nTime2), nTimeIndex * 0.000001);
  
      // Watch for changes to the previous coinbase transaction.
      static uint256 hashPrevBestCoinBase;
      g_signals.UpdatedTransaction(hashPrevBestCoinBase);
      hashPrevBestCoinBase = block.vtx[0].GetHash();
  
      int64_t nTime4 = GetTimeMicros();
      nTimeCallbacks += nTime4 - nTime3;
      LogPrint("bench", "    - Callbacks: %.2fms [%.2fs]\n", 0.001 * (nTime4 - nTime3), nTimeCallbacks * 0.000001);
  
      return true;
  }
  
  enum FlushStateMode {
      FLUSH_STATE_IF_NEEDED,
      FLUSH_STATE_PERIODIC,
      FLUSH_STATE_ALWAYS
  };
  
  /**
   * Update the on-disk chain state.
   * The caches and indexes are flushed if either they're too large, forceWrite is set, or
   * fast is not set and it's been a while since the last write.
   */
  bool static FlushStateToDisk(CValidationState& state, FlushStateMode mode)
  {
      LOCK(cs_main);
      static int64_t nLastWrite = 0;
      try {
          if ((mode == FLUSH_STATE_ALWAYS) ||
              ((mode == FLUSH_STATE_PERIODIC || mode == FLUSH_STATE_IF_NEEDED) && pcoinsTip->GetCacheSize() > nCoinCacheSize) ||
              (mode == FLUSH_STATE_PERIODIC && GetTimeMicros() > nLastWrite + DATABASE_WRITE_INTERVAL * 1000000)) {
              // Typical CCoins structures on disk are around 100 bytes in size.
              // Pushing a new one to the database can cause it to be written
              // twice (once in the log, and once in the tables). This is already
              // an overestimation, as most will delete an existing entry or
              // overwrite one. Still, use a conservative safety factor of 2.
              if (!CheckDiskSpace(100 * 2 * 2 * pcoinsTip->GetCacheSize()))
                  return state.Error("out of disk space");
              // First make sure all block and undo data is flushed to disk.
              FlushBlockFile();
              // Then update all block file information (which may refer to block and undo files).
              bool fileschanged = false;
              for (set<int>::iterator it = setDirtyFileInfo.begin(); it != setDirtyFileInfo.end();) {
                  if (!pblocktree->WriteBlockFileInfo(*it, vinfoBlockFile[*it])) {
                      return state.Abort("Failed to write to block index");
                  }
                  fileschanged = true;
                  setDirtyFileInfo.erase(it++);
              }
              if (fileschanged && !pblocktree->WriteLastBlockFile(nLastBlockFile)) {
                  return state.Abort("Failed to write to block index");
              }
              for (set<CBlockIndex*>::iterator it = setDirtyBlockIndex.begin(); it != setDirtyBlockIndex.end();) {
                  if (!pblocktree->WriteBlockIndex(CDiskBlockIndex(*it))) {
                      return state.Abort("Failed to write to block index");
                  }
                  setDirtyBlockIndex.erase(it++);
              }
              pblocktree->Sync();
              // Finally flush the chainstate (which may refer to block index entries).
              if (!pcoinsTip->Flush())
                  return state.Abort("Failed to write to coin database");
              // Update best block in wallet (so we can detect restored wallets).
              if (mode != FLUSH_STATE_IF_NEEDED) {
                  g_signals.SetBestChain(chainActive.GetLocator());
              }
              nLastWrite = GetTimeMicros();
          }
      } catch (const std::runtime_error& e) {
          return state.Abort(std::string("System error while flushing: ") + e.what());
      }
      return true;
  }
  
  void FlushStateToDisk()
  {
      CValidationState state;
      FlushStateToDisk(state, FLUSH_STATE_ALWAYS);
  }
  
  /** Update chainActive and related internal data structures. */
  void static UpdateTip(CBlockIndex* pindexNew)
  {
      chainActive.SetTip(pindexNew);
  
      // New best block
      nTimeBestReceived = GetTime();
      mempool.AddTransactionsUpdated(1);
  
      LogPrintf("UpdateTip: new best=%s  height=%d  log2_work=%.8g  tx=%lu  date=%s progress=%f  cache=%u\n",
          chainActive.Tip()->GetBlockHash().ToString(), chainActive.Height(), log(chainActive.Tip()->nChainWork.getdouble()) / log(2.0), (unsigned long)chainActive.Tip()->nChainTx,
          DateTimeStrFormat("%Y-%m-%d %H:%M:%S", chainActive.Tip()->GetBlockTime()),
          Checkpoints::GuessVerificationProgress(chainActive.Tip()), (unsigned int)pcoinsTip->GetCacheSize());
  
      cvBlockChange.notify_all();
  
      // Check the version of the last 100 blocks to see if we need to upgrade:
      static bool fWarned = false;
      if (!IsInitialBlockDownload() && !fWarned) {
          int nUpgraded = 0;
          const CBlockIndex* pindex = chainActive.Tip();
          for (int i = 0; i < 100 && pindex != NULL; i++) {
              if (pindex->nVersion > CBlock::CURRENT_VERSION)
                  ++nUpgraded;
              pindex = pindex->pprev;
          }
          if (nUpgraded > 0)
              LogPrintf("SetBestChain: %d of last 100 blocks above version %d\n", nUpgraded, (int)CBlock::CURRENT_VERSION);
          if (nUpgraded > 100 / 2) {
              // strMiscWarning is read by GetWarnings(), called by Qt and the JSON-RPC code to warn the user:
              strMiscWarning = _("Warning: This version is obsolete, upgrade required!");
              CAlert::Notify(strMiscWarning, true);
              fWarned = true;
          }
      }
  }
  
  /** Disconnect chainActive's tip. */
  bool static DisconnectTip(CValidationState& state)
  {
      CBlockIndex* pindexDelete = chainActive.Tip();
      assert(pindexDelete);
      mempool.check(pcoinsTip);
      // Read block from disk.
      CBlock block;
      if (!ReadBlockFromDisk(block, pindexDelete))
          return state.Abort("Failed to read block");
      // Apply the block atomically to the chain state.
      int64_t nStart = GetTimeMicros();
      {
          CCoinsViewCache view(pcoinsTip);
          if (!DisconnectBlock(block, state, pindexDelete, view))
              return error("DisconnectTip() : DisconnectBlock %s failed", pindexDelete->GetBlockHash().ToString());
          assert(view.Flush());
      }
      LogPrint("bench", "- Disconnect block: %.2fms\n", (GetTimeMicros() - nStart) * 0.001);
      // Write the chain state to disk, if necessary.
      if (!FlushStateToDisk(state, FLUSH_STATE_ALWAYS))
          return false;
      // Resurrect mempool transactions from the disconnected block.
      BOOST_FOREACH (const CTransaction& tx, block.vtx) {
          // ignore validation errors in resurrected transactions
          list<CTransaction> removed;
          CValidationState stateDummy;
          if (tx.IsCoinBase() || tx.IsCoinStake() || !AcceptToMemoryPool(mempool, stateDummy, tx, false, NULL))
              mempool.remove(tx, removed, true);
      }
      mempool.removeCoinbaseSpends(pcoinsTip, pindexDelete->nHeight);
      mempool.check(pcoinsTip);
      // Update chainActive and related variables.
      UpdateTip(pindexDelete->pprev);
      // Let wallets know transactions went from 1-confirmed to
      // 0-confirmed or conflicted:
      BOOST_FOREACH (const CTransaction& tx, block.vtx) {
          SyncWithWallets(tx, NULL);
      }
      return true;
  }
  
  static int64_t nTimeReadFromDisk = 0;
  static int64_t nTimeConnectTotal = 0;
  static int64_t nTimeFlush = 0;
  static int64_t nTimeChainState = 0;
  static int64_t nTimePostConnect = 0;
  
  /**
   * Connect a new block to chainActive. pblock is either NULL or a pointer to a CBlock
   * corresponding to pindexNew, to bypass loading it again from disk.
   */
  bool static ConnectTip(CValidationState& state, CBlockIndex* pindexNew, CBlock* pblock)
  {
      assert(pindexNew->pprev == chainActive.Tip());
      mempool.check(pcoinsTip);
      CCoinsViewCache view(pcoinsTip);
  
      // Read block from disk.
      int64_t nTime1 = GetTimeMicros();
      CBlock block;
      if (!pblock) {
          if (!ReadBlockFromDisk(block, pindexNew))
              return state.Abort("Failed to read block");
          pblock = &block;
      }
      // Apply the block atomically to the chain state.
      int64_t nTime2 = GetTimeMicros();
      nTimeReadFromDisk += nTime2 - nTime1;
      int64_t nTime3;
      LogPrint("bench", "  - Load block from disk: %.2fms [%.2fs]\n", (nTime2 - nTime1) * 0.001, nTimeReadFromDisk * 0.000001);
      {
          CInv inv(MSG_BLOCK, pindexNew->GetBlockHash());
          bool rv = ConnectBlock(*pblock, state, pindexNew, view);
          g_signals.BlockChecked(*pblock, state);
          if (!rv) {
              if (state.IsInvalid())
                  InvalidBlockFound(pindexNew, state);
              return error("ConnectTip() : ConnectBlock %s failed", pindexNew->GetBlockHash().ToString());
          }
          mapBlockSource.erase(inv.hash);
          nTime3 = GetTimeMicros();
          nTimeConnectTotal += nTime3 - nTime2;
          LogPrint("bench", "  - Connect total: %.2fms [%.2fs]\n", (nTime3 - nTime2) * 0.001, nTimeConnectTotal * 0.000001);
          assert(view.Flush());
      }
      int64_t nTime4 = GetTimeMicros();
      nTimeFlush += nTime4 - nTime3;
      LogPrint("bench", "  - Flush: %.2fms [%.2fs]\n", (nTime4 - nTime3) * 0.001, nTimeFlush * 0.000001);
  
      // Write the chain state to disk, if necessary. Always write to disk if this is the first of a new file.
      FlushStateMode flushMode = FLUSH_STATE_IF_NEEDED;
      if (pindexNew->pprev && (pindexNew->GetBlockPos().nFile != pindexNew->pprev->GetBlockPos().nFile))
          flushMode = FLUSH_STATE_ALWAYS;
      if (!FlushStateToDisk(state, flushMode))
          return false;
      int64_t nTime5 = GetTimeMicros();
      nTimeChainState += nTime5 - nTime4;
      LogPrint("bench", "  - Writing chainstate: %.2fms [%.2fs]\n", (nTime5 - nTime4) * 0.001, nTimeChainState * 0.000001);
  
      // Remove conflicting transactions from the mempool.
      list<CTransaction> txConflicted;
      mempool.removeForBlock(pblock->vtx, pindexNew->nHeight, txConflicted);
      mempool.check(pcoinsTip);
      // Update chainActive & related variables.
      UpdateTip(pindexNew);
      // Tell wallet about transactions that went from mempool
      // to conflicted:
      BOOST_FOREACH (const CTransaction& tx, txConflicted) {
          SyncWithWallets(tx, NULL);
      }
      // ... and about transactions that got confirmed:
      BOOST_FOREACH (const CTransaction& tx, pblock->vtx) {
          SyncWithWallets(tx, pblock);
      }
  
      int64_t nTime6 = GetTimeMicros();
      nTimePostConnect += nTime6 - nTime5;
      nTimeTotal += nTime6 - nTime1;
      LogPrint("bench", "  - Connect postprocess: %.2fms [%.2fs]\n", (nTime6 - nTime5) * 0.001, nTimePostConnect * 0.000001);
      LogPrint("bench", "- Connect block: %.2fms [%.2fs]\n", (nTime6 - nTime1) * 0.001, nTimeTotal * 0.000001);
      return true;
  }
  
  bool DisconnectBlocksAndReprocess(int blocks)
  {
      LOCK(cs_main);
  
      CValidationState state;
  
      LogPrintf("DisconnectBlocksAndReprocess: Got command to replay %d blocks\n", blocks);
      for (int i = 0; i <= blocks; i++)
          DisconnectTip(state);
  
      return true;
  }
  
  /*
      DisconnectBlockAndInputs
  
      Remove conflicting blocks for successful SwiftTX transaction locks
      This should be very rare (Probably will never happen)
  */
  // ***TODO*** clean up here
  bool DisconnectBlockAndInputs(CValidationState& state, CTransaction txLock)
  {
      // All modifications to the coin state will be done in this cache.
      // Only when all have succeeded, we push it to pcoinsTip.
      //    CCoinsViewCache view(*pcoinsTip, true);
  
      CBlockIndex* BlockReading = chainActive.Tip();
      CBlockIndex* pindexNew = NULL;
  
      bool foundConflictingTx = false;
  
      //remove anything conflicting in the memory pool
      list<CTransaction> txConflicted;
      mempool.removeConflicts(txLock, txConflicted);
  
  
      // List of what to disconnect (typically nothing)
      vector<CBlockIndex*> vDisconnect;
  
      for (unsigned int i = 1; BlockReading && BlockReading->nHeight > 0 && !foundConflictingTx && i < 6; i++) {
          vDisconnect.push_back(BlockReading);
          pindexNew = BlockReading->pprev; //new best block
  
          CBlock block;
          if (!ReadBlockFromDisk(block, BlockReading))
              return state.Abort(_("Failed to read block"));
  
          // Queue memory transactions to resurrect.
          // We only do this for blocks after the last checkpoint (reorganisation before that
          // point should only happen with -reindex/-loadblock, or a misbehaving peer.
          BOOST_FOREACH (const CTransaction& tx, block.vtx) {
              if (!tx.IsCoinBase()) {
                  BOOST_FOREACH (const CTxIn& in1, txLock.vin) {
                      BOOST_FOREACH (const CTxIn& in2, tx.vin) {
                          if (in1.prevout == in2.prevout) foundConflictingTx = true;
                      }
                  }
              }
          }
  
          if (BlockReading->pprev == NULL) {
              assert(BlockReading);
              break;
          }
          BlockReading = BlockReading->pprev;
      }
  
      if (!foundConflictingTx) {
          LogPrintf("DisconnectBlockAndInputs: Can't find a conflicting transaction to inputs\n");
          return false;
      }
  
      if (vDisconnect.size() > 0) {
          LogPrintf("REORGANIZE: Disconnect Conflicting Blocks %lli blocks; %s..\n", vDisconnect.size(), pindexNew->GetBlockHash().ToString());
          BOOST_FOREACH (CBlockIndex* pindex, vDisconnect) {
              LogPrintf(" -- disconnect %s\n", pindex->GetBlockHash().ToString());
              DisconnectTip(state);
          }
      }
  
      return true;
  }
  
  
  /**
   * Return the tip of the chain with the most work in it, that isn't
   * known to be invalid (it's however far from certain to be valid).
   */
  static CBlockIndex* FindMostWorkChain()
  {
      do {
          CBlockIndex* pindexNew = NULL;
  
          // Find the best candidate header.
          {
              std::set<CBlockIndex*, CBlockIndexWorkComparator>::reverse_iterator it = setBlockIndexCandidates.rbegin();
              if (it == setBlockIndexCandidates.rend())
                  return NULL;
              pindexNew = *it;
          }
  
          // Check whether all blocks on the path between the currently active chain and the candidate are valid.
          // Just going until the active chain is an optimization, as we know all blocks in it are valid already.
          CBlockIndex* pindexTest = pindexNew;
          bool fInvalidAncestor = false;
          while (pindexTest && !chainActive.Contains(pindexTest)) {
              assert(pindexTest->nChainTx || pindexTest->nHeight == 0);
  
              // Pruned nodes may have entries in setBlockIndexCandidates for
              // which block files have been deleted.  Remove those as candidates
              // for the most work chain if we come across them; we can't switch
              // to a chain unless we have all the non-active-chain parent blocks.
              bool fFailedChain = pindexTest->nStatus & BLOCK_FAILED_MASK;
              bool fMissingData = !(pindexTest->nStatus & BLOCK_HAVE_DATA);
              if (fFailedChain || fMissingData) {
                  // Candidate chain is not usable (either invalid or missing data)
                  if (fFailedChain && (pindexBestInvalid == NULL || pindexNew->nChainWork > pindexBestInvalid->nChainWork))
                      pindexBestInvalid = pindexNew;
                  CBlockIndex* pindexFailed = pindexNew;
                  // Remove the entire chain from the set.
                  while (pindexTest != pindexFailed) {
                      if (fFailedChain) {
                          pindexFailed->nStatus |= BLOCK_FAILED_CHILD;
                      } else if (fMissingData) {
                          // If we're missing data, then add back to mapBlocksUnlinked,
                          // so that if the block arrives in the future we can try adding
                          // to setBlockIndexCandidates again.
                          mapBlocksUnlinked.insert(std::make_pair(pindexFailed->pprev, pindexFailed));
                      }
                      setBlockIndexCandidates.erase(pindexFailed);
                      pindexFailed = pindexFailed->pprev;
                  }
                  setBlockIndexCandidates.erase(pindexTest);
                  fInvalidAncestor = true;
                  break;
              }
              pindexTest = pindexTest->pprev;
          }
          if (!fInvalidAncestor)
              return pindexNew;
      } while (true);
  }
  
  /** Delete all entries in setBlockIndexCandidates that are worse than the current tip. */
  static void PruneBlockIndexCandidates()
  {
      // Note that we can't delete the current block itself, as we may need to return to it later in case a
      // reorganization to a better block fails.
      std::set<CBlockIndex*, CBlockIndexWorkComparator>::iterator it = setBlockIndexCandidates.begin();
      while (it != setBlockIndexCandidates.end() && setBlockIndexCandidates.value_comp()(*it, chainActive.Tip())) {
          setBlockIndexCandidates.erase(it++);
      }
      // Either the current tip or a successor of it we're working towards is left in setBlockIndexCandidates.
      assert(!setBlockIndexCandidates.empty());
  }
  
  /**
   * Try to make some progress towards making pindexMostWork the active block.
   * pblock is either NULL or a pointer to a CBlock corresponding to pindexMostWork.
   */
  static bool ActivateBestChainStep(CValidationState& state, CBlockIndex* pindexMostWork, CBlock* pblock)
  {
      AssertLockHeld(cs_main);
      bool fInvalidFound = false;
      const CBlockIndex* pindexOldTip = chainActive.Tip();
      const CBlockIndex* pindexFork = chainActive.FindFork(pindexMostWork);
  
      // Disconnect active blocks which are no longer in the best chain.
      while (chainActive.Tip() && chainActive.Tip() != pindexFork) {
          if (!DisconnectTip(state))
              return false;
      }
  
      // Build list of new blocks to connect.
      std::vector<CBlockIndex*> vpindexToConnect;
      bool fContinue = true;
      int nHeight = pindexFork ? pindexFork->nHeight : -1;
      while (fContinue && nHeight != pindexMostWork->nHeight) {
          // Don't iterate the entire list of potential improvements toward the best tip, as we likely only need
          // a few blocks along the way.
          int nTargetHeight = std::min(nHeight + 32, pindexMostWork->nHeight);
          vpindexToConnect.clear();
          vpindexToConnect.reserve(nTargetHeight - nHeight);
          CBlockIndex* pindexIter = pindexMostWork->GetAncestor(nTargetHeight);
          while (pindexIter && pindexIter->nHeight != nHeight) {
              vpindexToConnect.push_back(pindexIter);
              pindexIter = pindexIter->pprev;
          }
          nHeight = nTargetHeight;
  
          // Connect new blocks.
          BOOST_REVERSE_FOREACH (CBlockIndex* pindexConnect, vpindexToConnect) {
              if (!ConnectTip(state, pindexConnect, pindexConnect == pindexMostWork ? pblock : NULL)) {
                  if (state.IsInvalid()) {
                      // The block violates a consensus rule.
                      if (!state.CorruptionPossible())
                          InvalidChainFound(vpindexToConnect.back());
                      state = CValidationState();
                      fInvalidFound = true;
                      fContinue = false;
                      break;
                  } else {
                      // A system error occurred (disk space, database error, ...).
                      return false;
                  }
              } else {
                  PruneBlockIndexCandidates();
                  if (!pindexOldTip || chainActive.Tip()->nChainWork > pindexOldTip->nChainWork) {
                      // We're in a better position than we were. Return temporarily to release the lock.
                      fContinue = false;
                      break;
                  }
              }
          }
      }
  
      // Callbacks/notifications for a new best chain.
      if (fInvalidFound)
          CheckForkWarningConditionsOnNewFork(vpindexToConnect.back());
      else
          CheckForkWarningConditions();
  
      return true;
  }
  
  /**
   * Make the best chain active, in multiple steps. The result is either failure
   * or an activated best chain. pblock is either NULL or a pointer to a block
   * that is already loaded (to avoid loading it again from disk).
   */
  bool ActivateBestChain(CValidationState& state, CBlock* pblock)
  {
      CBlockIndex* pindexNewTip = NULL;
      CBlockIndex* pindexMostWork = NULL;
      do {
          boost::this_thread::interruption_point();
  
          bool fInitialDownload;
          while (true) {
              TRY_LOCK(cs_main, lockMain);
              if (!lockMain) {
                  MilliSleep(50);
                  continue;
              }
  
              pindexMostWork = FindMostWorkChain();
  
              // Whether we have anything to do at all.
              if (pindexMostWork == NULL || pindexMostWork == chainActive.Tip())
                  return true;
  
              if (!ActivateBestChainStep(state, pindexMostWork, pblock && pblock->GetHash() == pindexMostWork->GetBlockHash() ? pblock : NULL))
                  return false;
  
              pindexNewTip = chainActive.Tip();
              fInitialDownload = IsInitialBlockDownload();
              break;
          }
          // When we reach this point, we switched to a new tip (stored in pindexNewTip).
  
          // Notifications/callbacks that can run without cs_main
          if (!fInitialDownload) {
              uint256 hashNewTip = pindexNewTip->GetBlockHash();
              // Relay inventory, but don't relay old inventory during initial block download.
              int nBlockEstimate = Checkpoints::GetTotalBlocksEstimate();
              {
                  LOCK(cs_vNodes);
                  BOOST_FOREACH (CNode* pnode, vNodes)
                      if (chainActive.Height() > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate))
                          pnode->PushInventory(CInv(MSG_BLOCK, hashNewTip));
              }
              // Notify external listeners about the new tip.
              uiInterface.NotifyBlockTip(hashNewTip);
          }
      } while (pindexMostWork != chainActive.Tip());
      CheckBlockIndex();
  
      // Write changes periodically to disk, after relay.
      if (!FlushStateToDisk(state, FLUSH_STATE_PERIODIC)) {
          return false;
      }
  
      return true;
  }
  
  bool InvalidateBlock(CValidationState& state, CBlockIndex* pindex)
  {
      AssertLockHeld(cs_main);
  
      // Mark the block itself as invalid.
      pindex->nStatus |= BLOCK_FAILED_VALID;
      setDirtyBlockIndex.insert(pindex);
      setBlockIndexCandidates.erase(pindex);
  
      while (chainActive.Contains(pindex)) {
          CBlockIndex* pindexWalk = chainActive.Tip();
          pindexWalk->nStatus |= BLOCK_FAILED_CHILD;
          setDirtyBlockIndex.insert(pindexWalk);
          setBlockIndexCandidates.erase(pindexWalk);
          // ActivateBestChain considers blocks already in chainActive
          // unconditionally valid already, so force disconnect away from it.
          if (!DisconnectTip(state)) {
              return false;
          }
      }
  
      // The resulting new best tip may not be in setBlockIndexCandidates anymore, so
      // add them again.
      BlockMap::iterator it = mapBlockIndex.begin();
      while (it != mapBlockIndex.end()) {
          if (it->second->IsValid(BLOCK_VALID_TRANSACTIONS) && it->second->nChainTx && !setBlockIndexCandidates.value_comp()(it->second, chainActive.Tip())) {
              setBlockIndexCandidates.insert(it->second);
          }
          it++;
      }
  
      InvalidChainFound(pindex);
      return true;
  }
  
  bool ReconsiderBlock(CValidationState& state, CBlockIndex* pindex)
  {
      AssertLockHeld(cs_main);
  
      int nHeight = pindex->nHeight;
  
      // Remove the invalidity flag from this block and all its descendants.
      BlockMap::iterator it = mapBlockIndex.begin();
      while (it != mapBlockIndex.end()) {
          if (!it->second->IsValid() && it->second->GetAncestor(nHeight) == pindex) {
              it->second->nStatus &= ~BLOCK_FAILED_MASK;
              setDirtyBlockIndex.insert(it->second);
              if (it->second->IsValid(BLOCK_VALID_TRANSACTIONS) && it->second->nChainTx && setBlockIndexCandidates.value_comp()(chainActive.Tip(), it->second)) {
                  setBlockIndexCandidates.insert(it->second);
              }
              if (it->second == pindexBestInvalid) {
                  // Reset invalid block marker if it was pointing to one of those.
                  pindexBestInvalid = NULL;
              }
          }
          it++;
      }
  
      // Remove the invalidity flag from all ancestors too.
      while (pindex != NULL) {
          if (pindex->nStatus & BLOCK_FAILED_MASK) {
              pindex->nStatus &= ~BLOCK_FAILED_MASK;
              setDirtyBlockIndex.insert(pindex);
          }
          pindex = pindex->pprev;
      }
      return true;
  }
  
  CBlockIndex* AddToBlockIndex(const CBlock& block)
  {
      // Check for duplicate
      uint256 hash = block.GetHash();
      BlockMap::iterator it = mapBlockIndex.find(hash);
      if (it != mapBlockIndex.end())
          return it->second;
  
      // Construct new block index object
      CBlockIndex* pindexNew = new CBlockIndex(block);
      assert(pindexNew);
      // We assign the sequence id to blocks only when the full data is available,
      // to avoid miners withholding blocks but broadcasting headers, to get a
      // competitive advantage.
      pindexNew->nSequenceId = 0;
      BlockMap::iterator mi = mapBlockIndex.insert(make_pair(hash, pindexNew)).first;
  
      //mark as PoS seen
      if (pindexNew->IsProofOfStake())
          setStakeSeen.insert(make_pair(pindexNew->prevoutStake, pindexNew->nStakeTime));
  
      pindexNew->phashBlock = &((*mi).first);
      BlockMap::iterator miPrev = mapBlockIndex.find(block.hashPrevBlock);
      if (miPrev != mapBlockIndex.end()) {
          pindexNew->pprev = (*miPrev).second;
          pindexNew->nHeight = pindexNew->pprev->nHeight + 1;
          pindexNew->BuildSkip();
  
          //update previous block pointer
          pindexNew->pprev->pnext = pindexNew;
  
          // ppcoin: compute chain trust score
          pindexNew->bnChainTrust = (pindexNew->pprev ? pindexNew->pprev->bnChainTrust : 0) + pindexNew->GetBlockTrust();
  
          // ppcoin: compute stake entropy bit for stake modifier
          if (!pindexNew->SetStakeEntropyBit(pindexNew->GetStakeEntropyBit()))
              LogPrintf("AddToBlockIndex() : SetStakeEntropyBit() failed \n");
  
          // ppcoin: record proof-of-stake hash value
          if (pindexNew->IsProofOfStake()) {
              if (!mapProofOfStake.count(hash))
                  LogPrintf("AddToBlockIndex() : hashProofOfStake not found in map \n");
              pindexNew->hashProofOfStake = mapProofOfStake[hash];
          }
  
          // ppcoin: compute stake modifier
          uint64_t nStakeModifier = 0;
          bool fGeneratedStakeModifier = false;
          if (!ComputeNextStakeModifier(pindexNew->pprev, nStakeModifier, fGeneratedStakeModifier))
              LogPrintf("AddToBlockIndex() : ComputeNextStakeModifier() failed \n");
          pindexNew->SetStakeModifier(nStakeModifier, fGeneratedStakeModifier);
          pindexNew->nStakeModifierChecksum = GetStakeModifierChecksum(pindexNew);
          if (!CheckStakeModifierCheckpoints(pindexNew->nHeight, pindexNew->nStakeModifierChecksum))
              LogPrintf("AddToBlockIndex() : Rejected by stake modifier checkpoint height=%d, modifier=%s \n", pindexNew->nHeight, boost::lexical_cast<std::string>(nStakeModifier));
      }
      pindexNew->nChainWork = (pindexNew->pprev ? pindexNew->pprev->nChainWork : 0) + GetBlockProof(*pindexNew);
      pindexNew->RaiseValidity(BLOCK_VALID_TREE);
      if (pindexBestHeader == NULL || pindexBestHeader->nChainWork < pindexNew->nChainWork)
          pindexBestHeader = pindexNew;
  
      //update previous block pointer
      if (pindexNew->nHeight)
          pindexNew->pprev->pnext = pindexNew;
  
      setDirtyBlockIndex.insert(pindexNew);
  
      return pindexNew;
  }
  
  /** Mark a block as having its data received and checked (up to BLOCK_VALID_TRANSACTIONS). */
  bool ReceivedBlockTransactions(const CBlock& block, CValidationState& state, CBlockIndex* pindexNew, const CDiskBlockPos& pos)
  {
      if (block.IsProofOfStake())
          pindexNew->SetProofOfStake();
      pindexNew->nTx = block.vtx.size();
      pindexNew->nChainTx = 0;
      pindexNew->nFile = pos.nFile;
      pindexNew->nDataPos = pos.nPos;
      pindexNew->nUndoPos = 0;
      pindexNew->nStatus |= BLOCK_HAVE_DATA;
      pindexNew->RaiseValidity(BLOCK_VALID_TRANSACTIONS);
      setDirtyBlockIndex.insert(pindexNew);
  
      if (pindexNew->pprev == NULL || pindexNew->pprev->nChainTx) {
          // If pindexNew is the genesis block or all parents are BLOCK_VALID_TRANSACTIONS.
          deque<CBlockIndex*> queue;
          queue.push_back(pindexNew);
  
          // Recursively process any descendant blocks that now may be eligible to be connected.
          while (!queue.empty()) {
              CBlockIndex* pindex = queue.front();
              queue.pop_front();
              pindex->nChainTx = (pindex->pprev ? pindex->pprev->nChainTx : 0) + pindex->nTx;
              {
                  LOCK(cs_nBlockSequenceId);
                  pindex->nSequenceId = nBlockSequenceId++;
              }
              if (chainActive.Tip() == NULL || !setBlockIndexCandidates.value_comp()(pindex, chainActive.Tip())) {
                  setBlockIndexCandidates.insert(pindex);
              }
              std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> range = mapBlocksUnlinked.equal_range(pindex);
              while (range.first != range.second) {
                  std::multimap<CBlockIndex*, CBlockIndex*>::iterator it = range.first;
                  queue.push_back(it->second);
                  range.first++;
                  mapBlocksUnlinked.erase(it);
              }
          }
      } else {
          if (pindexNew->pprev && pindexNew->pprev->IsValid(BLOCK_VALID_TREE)) {
              mapBlocksUnlinked.insert(std::make_pair(pindexNew->pprev, pindexNew));
          }
      }
  
      return true;
  }
  
  bool FindBlockPos(CValidationState& state, CDiskBlockPos& pos, unsigned int nAddSize, unsigned int nHeight, uint64_t nTime, bool fKnown = false)
  {
      LOCK(cs_LastBlockFile);
  
      unsigned int nFile = fKnown ? pos.nFile : nLastBlockFile;
      if (vinfoBlockFile.size() <= nFile) {
          vinfoBlockFile.resize(nFile + 1);
      }
  
      if (!fKnown) {
          while (vinfoBlockFile[nFile].nSize + nAddSize >= MAX_BLOCKFILE_SIZE) {
              LogPrintf("Leaving block file %i: %s\n", nFile, vinfoBlockFile[nFile].ToString());
              FlushBlockFile(true);
              nFile++;
              if (vinfoBlockFile.size() <= nFile) {
                  vinfoBlockFile.resize(nFile + 1);
              }
          }
          pos.nFile = nFile;
          pos.nPos = vinfoBlockFile[nFile].nSize;
      }
  
      nLastBlockFile = nFile;
      vinfoBlockFile[nFile].AddBlock(nHeight, nTime);
      if (fKnown)
          vinfoBlockFile[nFile].nSize = std::max(pos.nPos + nAddSize, vinfoBlockFile[nFile].nSize);
      else
          vinfoBlockFile[nFile].nSize += nAddSize;
  
      if (!fKnown) {
          unsigned int nOldChunks = (pos.nPos + BLOCKFILE_CHUNK_SIZE - 1) / BLOCKFILE_CHUNK_SIZE;
          unsigned int nNewChunks = (vinfoBlockFile[nFile].nSize + BLOCKFILE_CHUNK_SIZE - 1) / BLOCKFILE_CHUNK_SIZE;
          if (nNewChunks > nOldChunks) {
              if (CheckDiskSpace(nNewChunks * BLOCKFILE_CHUNK_SIZE - pos.nPos)) {
                  FILE* file = OpenBlockFile(pos);
                  if (file) {
                      LogPrintf("Pre-allocating up to position 0x%x in blk%05u.dat\n", nNewChunks * BLOCKFILE_CHUNK_SIZE, pos.nFile);
                      AllocateFileRange(file, pos.nPos, nNewChunks * BLOCKFILE_CHUNK_SIZE - pos.nPos);
                      fclose(file);
                  }
              } else
                  return state.Error("out of disk space");
          }
      }
  
      setDirtyFileInfo.insert(nFile);
      return true;
  }
  
  bool FindUndoPos(CValidationState& state, int nFile, CDiskBlockPos& pos, unsigned int nAddSize)
  {
      pos.nFile = nFile;
  
      LOCK(cs_LastBlockFile);
  
      unsigned int nNewSize;
      pos.nPos = vinfoBlockFile[nFile].nUndoSize;
      nNewSize = vinfoBlockFile[nFile].nUndoSize += nAddSize;
      setDirtyFileInfo.insert(nFile);
  
      unsigned int nOldChunks = (pos.nPos + UNDOFILE_CHUNK_SIZE - 1) / UNDOFILE_CHUNK_SIZE;
      unsigned int nNewChunks = (nNewSize + UNDOFILE_CHUNK_SIZE - 1) / UNDOFILE_CHUNK_SIZE;
      if (nNewChunks > nOldChunks) {
          if (CheckDiskSpace(nNewChunks * UNDOFILE_CHUNK_SIZE - pos.nPos)) {
              FILE* file = OpenUndoFile(pos);
              if (file) {
                  LogPrintf("Pre-allocating up to position 0x%x in rev%05u.dat\n", nNewChunks * UNDOFILE_CHUNK_SIZE, pos.nFile);
                  AllocateFileRange(file, pos.nPos, nNewChunks * UNDOFILE_CHUNK_SIZE - pos.nPos);
                  fclose(file);
              }
          } else
              return state.Error("out of disk space");
      }
  
      return true;
  }
  
  bool CheckBlockHeader(const CBlockHeader& block, CValidationState& state, bool fCheckPOW)
  {
      // Check proof of work matches claimed amount
      if (fCheckPOW && !CheckProofOfWork(block.GetHash(), block.nBits))
          return state.DoS(50, error("CheckBlockHeader() : proof of work failed"),
              REJECT_INVALID, "high-hash");
  
      return true;
  }
  
  bool CheckBlock(const CBlock& block, CValidationState& state, bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig)
  {
      // These are checks that are independent of context.
  
      // Check that the header is valid (particularly PoW).  This is mostly
      // redundant with the call in AcceptBlockHeader.
      if (!CheckBlockHeader(block, state, block.IsProofOfWork()))
          return state.DoS(100, error("CheckBlock() : CheckBlockHeader failed"),
              REJECT_INVALID, "bad-header", true);
  
      // Check timestamp
      LogPrint("debug", "%s: block=%s  is proof of stake=%d\n", __func__, block.GetHash().ToString().c_str(), block.IsProofOfStake());
      if (block.GetBlockTime() > GetAdjustedTime() + (block.IsProofOfStake() ? 180 : 7200)) // 3 minute future drift for PoS
          return state.Invalid(error("CheckBlock() : block timestamp too far in the future"),
              REJECT_INVALID, "time-too-new");
  
  
      // Check the merkle root.
      if (fCheckMerkleRoot) {
          bool mutated;
          uint256 hashMerkleRoot2 = block.BuildMerkleTree(&mutated);
          if (block.hashMerkleRoot != hashMerkleRoot2)
              return state.DoS(100, error("CheckBlock() : hashMerkleRoot mismatch"),
                  REJECT_INVALID, "bad-txnmrklroot", true);
  
          // Check for merkle tree malleability (CVE-2012-2459): repeating sequences
          // of transactions in a block without affecting the merkle root of a block,
          // while still invalidating it.
          if (mutated)
              return state.DoS(100, error("CheckBlock() : duplicate transaction"),
                  REJECT_INVALID, "bad-txns-duplicate", true);
      }
  
      // All potential-corruption validation must be done before we do any
      // transaction validation, as otherwise we may mark the header as invalid
      // because we receive the wrong transactions for it.
  
      // Size limits
      if (block.vtx.empty() || block.vtx.size() > MAX_BLOCK_SIZE || ::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
          return state.DoS(100, error("CheckBlock() : size limits failed"),
              REJECT_INVALID, "bad-blk-length");
  
      // First transaction must be coinbase, the rest must not be
      if (block.vtx.empty() || !block.vtx[0].IsCoinBase())
          return state.DoS(100, error("CheckBlock() : first tx is not coinbase"),
              REJECT_INVALID, "bad-cb-missing");
      for (unsigned int i = 1; i < block.vtx.size(); i++)
          if (block.vtx[i].IsCoinBase())
              return state.DoS(100, error("CheckBlock() : more than one coinbase"),
                  REJECT_INVALID, "bad-cb-multiple");
  
      if (block.IsProofOfStake()) {
          // Coinbase output should be empty if proof-of-stake block
          if (block.vtx[0].vout.size() != 1 || !block.vtx[0].vout[0].IsEmpty())
              return state.DoS(100, error("CheckBlock() : coinbase output not empty for proof-of-stake block"));
  
          // Second transaction must be coinstake, the rest must not be
          if (block.vtx.empty() || !block.vtx[1].IsCoinStake())
              return state.DoS(100, error("CheckBlock() : second tx is not coinstake"));
          for (unsigned int i = 2; i < block.vtx.size(); i++)
              if (block.vtx[i].IsCoinStake())
                  return state.DoS(100, error("CheckBlock() : more than one coinstake"));
      }
  
      // ----------- swiftTX transaction scanning -----------
  
      if (IsSporkActive(SPORK_3_SWIFTTX_BLOCK_FILTERING)) {
          BOOST_FOREACH (const CTransaction& tx, block.vtx) {
              if (!tx.IsCoinBase()) {
                  //only reject blocks when it's based on complete consensus
                  BOOST_FOREACH (const CTxIn& in, tx.vin) {
                      if (mapLockedInputs.count(in.prevout)) {
                          if (mapLockedInputs[in.prevout] != tx.GetHash()) {
                              mapRejectedBlocks.insert(make_pair(block.GetHash(), GetTime()));
                              LogPrintf("CheckBlock() : found conflicting transaction with transaction lock %s %s\n", mapLockedInputs[in.prevout].ToString(), tx.GetHash().ToString());
                              return state.DoS(0, error("CheckBlock() : found conflicting transaction with transaction lock"),
                                  REJECT_INVALID, "conflicting-tx-ix");
                          }
                      }
                  }
              }
          }
      } else {
          LogPrintf("CheckBlock() : skipping transaction locking checks\n");
      }
  
  
      // ----------- masternode payments / budgets -----------
  
      CBlockIndex* pindexPrev = chainActive.Tip();
      if (pindexPrev != NULL) {
          int nHeight = 0;
          if (pindexPrev->GetBlockHash() == block.hashPrevBlock) {
              nHeight = pindexPrev->nHeight + 1;
          } else { //out of order
              BlockMap::iterator mi = mapBlockIndex.find(block.hashPrevBlock);
              if (mi != mapBlockIndex.end() && (*mi).second)
                  nHeight = (*mi).second->nHeight + 1;
          }
  
          if (nHeight != 0 && !IsInitialBlockDownload()) {
              if (!IsBlockPayeeValid(block, nHeight)) {
                  mapRejectedBlocks.insert(make_pair(block.GetHash(), GetTime()));
                  return state.DoS(100, error("CheckBlock() : Couldn't find masternode/budget payment"));
              }
          } else {
              if (fDebug)
                  LogPrintf("CheckBlock(): Masternode payment check skipped on sync - skipping IsBlockPayeeValid()\n");
          }
      }
  
      // -------------------------------------------
  
      // Check transactions
      BOOST_FOREACH (const CTransaction& tx, block.vtx)
          if (!CheckTransaction(tx, state))
              return error("CheckBlock() : CheckTransaction failed");
  
      unsigned int nSigOps = 0;
      BOOST_FOREACH (const CTransaction& tx, block.vtx) {
          nSigOps += GetLegacySigOpCount(tx);
      }
      if (nSigOps > MAX_BLOCK_SIGOPS)
          return state.DoS(100, error("CheckBlock() : out-of-bounds SigOpCount"),
              REJECT_INVALID, "bad-blk-sigops", true);
  
      return true;
  }
  
  bool CheckWork(const CBlock block, CBlockIndex* const pindexPrev)
  {
      if (pindexPrev == NULL)
          return error("%s : null pindexPrev for block %s", __func__, block.GetHash().ToString().c_str());
  
      unsigned int nBitsRequired = GetNextWorkRequired(pindexPrev, &block);
  
      if (block.IsProofOfWork() && (pindexPrev->nHeight + 1 <= 68589)) {
          double n1 = ConvertBitsToDouble(block.nBits);
          double n2 = ConvertBitsToDouble(nBitsRequired);
  
          if (abs(n1 - n2) > n1 * 0.5)
              return error("%s : incorrect proof of work (DGW pre-fork) - %f %f %f at %d", __func__, abs(n1 - n2), n1, n2, pindexPrev->nHeight + 1);
  
          return true;
      }
  
      if (block.nBits != nBitsRequired)
          return error("%s : incorrect proof of work at %d", __func__, pindexPrev->nHeight + 1);
  
      if (block.IsProofOfStake()) {
          uint256 hashProofOfStake;
          uint256 hash = block.GetHash();
  
          if(!CheckProofOfStake(block, hashProofOfStake)) {
              LogPrintf("WARNING: ProcessBlock(): check proof-of-stake failed for block %s\n", hash.ToString().c_str());
              return false;
          }
          if(!mapProofOfStake.count(hash)) // add to mapProofOfStake
              mapProofOfStake.insert(make_pair(hash, hashProofOfStake));
      }
  
      return true;
  }
  
  bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationState& state, CBlockIndex* const pindexPrev)
  {
      uint256 hash = block.GetHash();
  
      if (hash == Params().HashGenesisBlock())
          return true;
  
      assert(pindexPrev);
  
      int nHeight = pindexPrev->nHeight + 1;
  
      //If this is a reorg, check that it is not too depp
      if (chainActive.Height() - nHeight >= Params().MaxReorganizationDepth())
          return state.DoS(1, error("%s: forked chain older than max reorganization depth (height %d)", __func__, nHeight));
  
      // Check timestamp against prev
      if (block.GetBlockTime() <= pindexPrev->GetMedianTimePast()) {
          LogPrintf("Block time = %d , GetMedianTimePast = %d \n", block.GetBlockTime(), pindexPrev->GetMedianTimePast());
          return state.Invalid(error("%s : block's timestamp is too early", __func__),
              REJECT_INVALID, "time-too-old");
      }
  
      // Check that the block chain matches the known block chain up to a checkpoint
      if (!Checkpoints::CheckBlock(nHeight, hash))
          return state.DoS(100, error("%s : rejected by checkpoint lock-in at %d", __func__, nHeight),
              REJECT_CHECKPOINT, "checkpoint mismatch");
  
      // Don't accept any forks from the main chain prior to last checkpoint
      CBlockIndex* pcheckpoint = Checkpoints::GetLastCheckpoint();
      if (pcheckpoint && nHeight < pcheckpoint->nHeight)
          return state.DoS(0, error("%s : forked chain older than last checkpoint (height %d)", __func__, nHeight));
  
      // Reject block.nVersion=1 blocks when 95% (75% on testnet) of the network has upgraded:
      if (block.nVersion < 2 &&
          CBlockIndex::IsSuperMajority(2, pindexPrev, Params().RejectBlockOutdatedMajority())) {
          return state.Invalid(error("%s : rejected nVersion=1 block", __func__),
              REJECT_OBSOLETE, "bad-version");
      }
  
      // Reject block.nVersion=2 blocks when 95% (75% on testnet) of the network has upgraded:
      if (block.nVersion < 3 && CBlockIndex::IsSuperMajority(3, pindexPrev, Params().RejectBlockOutdatedMajority())) {
          return state.Invalid(error("%s : rejected nVersion=2 block", __func__),
              REJECT_OBSOLETE, "bad-version");
      }
  
      return true;
  }
  
  bool ContextualCheckBlock(const CBlock& block, CValidationState& state, CBlockIndex* const pindexPrev)
  {
      const int nHeight = pindexPrev == NULL ? 0 : pindexPrev->nHeight + 1;
  
      // Check that all transactions are finalized
      BOOST_FOREACH (const CTransaction& tx, block.vtx)
          if (!IsFinalTx(tx, nHeight, block.GetBlockTime())) {
              return state.DoS(10, error("%s : contains a non-final transaction", __func__), REJECT_INVALID, "bad-txns-nonfinal");
          }
  
      // Enforce block.nVersion=2 rule that the coinbase starts with serialized block height
      // if 750 of the last 1,000 blocks are version 2 or greater (51/100 if testnet):
      if (block.nVersion >= 2 &&
          CBlockIndex::IsSuperMajority(2, pindexPrev, Params().EnforceBlockUpgradeMajority())) {
          CScript expect = CScript() << nHeight;
          if (block.vtx[0].vin[0].scriptSig.size() < expect.size() ||
              !std::equal(expect.begin(), expect.end(), block.vtx[0].vin[0].scriptSig.begin())) {
              return state.DoS(100, error("%s : block height mismatch in coinbase", __func__), REJECT_INVALID, "bad-cb-height");
          }
      }
  
      return true;
  }
  
  bool AcceptBlockHeader(const CBlock& block, CValidationState& state, CBlockIndex** ppindex)
  {
      AssertLockHeld(cs_main);
      // Check for duplicate
      uint256 hash = block.GetHash();
      BlockMap::iterator miSelf = mapBlockIndex.find(hash);
      CBlockIndex* pindex = NULL;
  
      // TODO : ENABLE BLOCK CACHE IN SPECIFIC CASES
      if (miSelf != mapBlockIndex.end()) {
          // Block header is already known.
          pindex = miSelf->second;
          if (ppindex)
              *ppindex = pindex;
          if (pindex->nStatus & BLOCK_FAILED_MASK)
              return state.Invalid(error("%s : block is marked invalid", __func__), 0, "duplicate");
          return true;
      }
  
      if (!CheckBlockHeader(block, state, false)) {
          LogPrintf("AcceptBlockHeader(): CheckBlockHeader failed \n");
          return false;
      }
  
      // Get prev block index
      CBlockIndex* pindexPrev = NULL;
      if (hash != Params().HashGenesisBlock()) {
          BlockMap::iterator mi = mapBlockIndex.find(block.hashPrevBlock);
          if (mi == mapBlockIndex.end())
              return state.DoS(0, error("%s : prev block %s not found", __func__, block.hashPrevBlock.ToString().c_str()), 0, "bad-prevblk");
          pindexPrev = (*mi).second;
          if (pindexPrev->nStatus & BLOCK_FAILED_MASK)
              return state.DoS(100, error("%s : prev block invalid", __func__), REJECT_INVALID, "bad-prevblk");
      }
  
      if (!ContextualCheckBlockHeader(block, state, pindexPrev))
          return false;
  
      if (pindex == NULL)
          pindex = AddToBlockIndex(block);
  
      if (ppindex)
          *ppindex = pindex;
  
      return true;
  }
  
  bool AcceptBlock(CBlock& block, CValidationState& state, CBlockIndex** ppindex, CDiskBlockPos* dbp)
  {
      AssertLockHeld(cs_main);
  
      CBlockIndex*& pindex = *ppindex;
  
      // Get prev block index
      CBlockIndex* pindexPrev = NULL;
      if (block.GetHash() != Params().HashGenesisBlock()) {
          BlockMap::iterator mi = mapBlockIndex.find(block.hashPrevBlock);
          if (mi == mapBlockIndex.end())
              return state.DoS(0, error("%s : prev block %s not found", __func__, block.hashPrevBlock.ToString().c_str()), 0, "bad-prevblk");
          pindexPrev = (*mi).second;
          if (pindexPrev->nStatus & BLOCK_FAILED_MASK)
              return state.DoS(100, error("%s : prev block invalid", __func__), REJECT_INVALID, "bad-prevblk");
      }
  
      if (block.GetHash() != Params().HashGenesisBlock() && !CheckWork(block, pindexPrev))
          return false;
  
      if (!AcceptBlockHeader(block, state, &pindex))
          return false;
  
      if (pindex->nStatus & BLOCK_HAVE_DATA) {
          // TODO: deal better with duplicate blocks.
          // return state.DoS(20, error("AcceptBlock() : already have block %d %s", pindex->nHeight, pindex->GetBlockHash().ToString()), REJECT_DUPLICATE, "duplicate");
          return true;
      }
  
      if ((!CheckBlock(block, state)) || !ContextualCheckBlock(block, state, pindex->pprev)) {
          if (state.IsInvalid() && !state.CorruptionPossible()) {
              pindex->nStatus |= BLOCK_FAILED_VALID;
              setDirtyBlockIndex.insert(pindex);
          }
          return false;
      }
  
      int nHeight = pindex->nHeight;
  
      // Write block to history file
      try {
          unsigned int nBlockSize = ::GetSerializeSize(block, SER_DISK, CLIENT_VERSION);
          CDiskBlockPos blockPos;
          if (dbp != NULL)
              blockPos = *dbp;
          if (!FindBlockPos(state, blockPos, nBlockSize + 8, nHeight, block.GetBlockTime(), dbp != NULL))
              return error("AcceptBlock() : FindBlockPos failed");
          if (dbp == NULL)
              if (!WriteBlockToDisk(block, blockPos))
                  return state.Abort("Failed to write block");
          if (!ReceivedBlockTransactions(block, state, pindex, blockPos))
              return error("AcceptBlock() : ReceivedBlockTransactions failed");
      } catch (std::runtime_error& e) {
          return state.Abort(std::string("System error: ") + e.what());
      }
  
      return true;
  }
  
  bool CBlockIndex::IsSuperMajority(int minVersion, const CBlockIndex* pstart, unsigned int nRequired)
  {
      unsigned int nToCheck = Params().ToCheckBlockUpgradeMajority();
      unsigned int nFound = 0;
      for (unsigned int i = 0; i < nToCheck && nFound < nRequired && pstart != NULL; i++) {
          if (pstart->nVersion >= minVersion)
              ++nFound;
          pstart = pstart->pprev;
      }
      return (nFound >= nRequired);
  }
  
  /** Turn the lowest '1' bit in the binary representation of a number into a '0'. */
  int static inline InvertLowestOne(int n) { return n & (n - 1); }
  
  /** Compute what height to jump back to with the CBlockIndex::pskip pointer. */
  int static inline GetSkipHeight(int height)
  {
      if (height < 2)
          return 0;
  
      // Determine which height to jump back to. Any number strictly lower than height is acceptable,
      // but the following expression seems to perform well in simulations (max 110 steps to go back
      // up to 2**18 blocks).
      return (height & 1) ? InvertLowestOne(InvertLowestOne(height - 1)) + 1 : InvertLowestOne(height);
  }
  
  CBlockIndex* CBlockIndex::GetAncestor(int height)
  {
      if (height > nHeight || height < 0)
          return NULL;
  
      CBlockIndex* pindexWalk = this;
      int heightWalk = nHeight;
      while (heightWalk > height) {
          int heightSkip = GetSkipHeight(heightWalk);
          int heightSkipPrev = GetSkipHeight(heightWalk - 1);
          if (heightSkip == height ||
              (heightSkip > height && !(heightSkipPrev < heightSkip - 2 && heightSkipPrev >= height))) {
              // Only follow pskip if pprev->pskip isn't better than pskip->pprev.
              pindexWalk = pindexWalk->pskip;
              heightWalk = heightSkip;
          } else {
              pindexWalk = pindexWalk->pprev;
              heightWalk--;
          }
      }
      return pindexWalk;
  }
  
  const CBlockIndex* CBlockIndex::GetAncestor(int height) const
  {
      return const_cast<CBlockIndex*>(this)->GetAncestor(height);
  }
  
  void CBlockIndex::BuildSkip()
  {
      if (pprev)
          pskip = pprev->GetAncestor(GetSkipHeight(nHeight));
  }
  
  bool ProcessNewBlock(CValidationState& state, CNode* pfrom, CBlock* pblock, CDiskBlockPos* dbp)
  {
      // Preliminary checks
      bool checked = CheckBlock(*pblock, state);
  
      // ppcoin: check proof-of-stake
      // Limited duplicity on stake: prevents block flood attack
      // Duplicate stake allowed only when there is orphan child block
      //if (pblock->IsProofOfStake() && setStakeSeen.count(pblock->GetProofOfStake())/* && !mapOrphanBlocksByPrev.count(hash)*/)
      //    return error("ProcessNewBlock() : duplicate proof-of-stake (%s, %d) for block %s", pblock->GetProofOfStake().first.ToString().c_str(), pblock->GetProofOfStake().second, pblock->GetHash().ToString().c_str());
  
      // NovaCoin: check proof-of-stake block signature
      if (!pblock->CheckBlockSignature())
          return error("ProcessNewBlock() : bad proof-of-stake block signature");
  
      if (pblock->GetHash() != Params().HashGenesisBlock() && pfrom != NULL) {
          //if we get this far, check if the prev block is our prev block, if not then request sync and return false
          BlockMap::iterator mi = mapBlockIndex.find(pblock->hashPrevBlock);
          if (mi == mapBlockIndex.end()) {
              pfrom->PushMessage("getblocks", chainActive.GetLocator(), uint256(0));
              return false;
          }
      }
  
      while (true) {
          TRY_LOCK(cs_main, lockMain);
          if (!lockMain) {
              MilliSleep(50);
              continue;
          }
  
          MarkBlockAsReceived(pblock->GetHash());
          if (!checked) {
              return error("%s : CheckBlock FAILED", __func__);
          }
  
          // Store to disk
          CBlockIndex* pindex = NULL;
          bool ret = AcceptBlock(*pblock, state, &pindex, dbp);
          if (pindex && pfrom) {
              mapBlockSource[pindex->GetBlockHash()] = pfrom->GetId();
          }
          CheckBlockIndex();
          if (!ret)
              return error("%s : AcceptBlock FAILED", __func__);
          break;
      }
  
      if (!ActivateBestChain(state, pblock))
          return error("%s : ActivateBestChain failed", __func__);
  
      if (!fLiteMode) {
          if (masternodeSync.RequestedMasternodeAssets > MASTERNODE_SYNC_LIST) {
              obfuScationPool.NewBlock();
              masternodePayments.ProcessBlock(GetHeight() + 10);
              budget.NewBlock();
          }
      }
  
      if (pwalletMain) {
          // If turned on MultiSend will send a transaction (or more) on the after maturity of a stake
          if (pwalletMain->isMultiSendEnabled())
              pwalletMain->MultiSend();
  
          //If turned on Auto Combine will scan wallet for dust to combine
          if (pwalletMain->fCombineDust)
              pwalletMain->AutoCombineDust();
      }
  
      LogPrintf("%s : ACCEPTED\n", __func__);
  
      return true;
  }
  
  bool TestBlockValidity(CValidationState& state, const CBlock& block, CBlockIndex* const pindexPrev, bool fCheckPOW, bool fCheckMerkleRoot)
  {
      AssertLockHeld(cs_main);
      assert(pindexPrev == chainActive.Tip());
  
      CCoinsViewCache viewNew(pcoinsTip);
      CBlockIndex indexDummy(block);
      indexDummy.pprev = pindexPrev;
      indexDummy.nHeight = pindexPrev->nHeight + 1;
  
      // NOTE: CheckBlockHeader is called by CheckBlock
      if (!ContextualCheckBlockHeader(block, state, pindexPrev))
          return false;
      if (!CheckBlock(block, state, fCheckPOW, fCheckMerkleRoot))
          return false;
      if (!ContextualCheckBlock(block, state, pindexPrev))
          return false;
      if (!ConnectBlock(block, state, &indexDummy, viewNew, true))
          return false;
      assert(state.IsValid());
  
      return true;
  }
  
  
  bool AbortNode(const std::string& strMessage, const std::string& userMessage)
  {
      strMiscWarning = strMessage;
      LogPrintf("*** %s\n", strMessage);
      uiInterface.ThreadSafeMessageBox(
          userMessage.empty() ? _("Error: A fatal internal error occured, see debug.log for details") : userMessage,
          "", CClientUIInterface::MSG_ERROR);
      StartShutdown();
      return false;
  }
  
  bool CheckDiskSpace(uint64_t nAdditionalBytes)
  {
      uint64_t nFreeBytesAvailable = filesystem::space(GetDataDir()).available;
  
      // Check for nMinDiskSpace bytes (currently 50MB)
      if (nFreeBytesAvailable < nMinDiskSpace + nAdditionalBytes)
          return AbortNode("Disk space is low!", _("Error: Disk space is low!"));
  
      return true;
  }
  
  FILE* OpenDiskFile(const CDiskBlockPos& pos, const char* prefix, bool fReadOnly)
  {
      if (pos.IsNull())
          return NULL;
      boost::filesystem::path path = GetBlockPosFilename(pos, prefix);
      boost::filesystem::create_directories(path.parent_path());
      FILE* file = fopen(path.string().c_str(), "rb+");
      if (!file && !fReadOnly)
          file = fopen(path.string().c_str(), "wb+");
      if (!file) {
          LogPrintf("Unable to open file %s\n", path.string());
          return NULL;
      }
      if (pos.nPos) {
          if (fseek(file, pos.nPos, SEEK_SET)) {
              LogPrintf("Unable to seek to position %u of %s\n", pos.nPos, path.string());
              fclose(file);
              return NULL;
          }
      }
      return file;
  }
  
  FILE* OpenBlockFile(const CDiskBlockPos& pos, bool fReadOnly)
  {
      return OpenDiskFile(pos, "blk", fReadOnly);
  }
  
  FILE* OpenUndoFile(const CDiskBlockPos& pos, bool fReadOnly)
  {
      return OpenDiskFile(pos, "rev", fReadOnly);
  }
  
  boost::filesystem::path GetBlockPosFilename(const CDiskBlockPos& pos, const char* prefix)
  {
      return GetDataDir() / "blocks" / strprintf("%s%05u.dat", prefix, pos.nFile);
  }
  
  CBlockIndex* InsertBlockIndex(uint256 hash)
  {
      if (hash == 0)
          return NULL;
  
      // Return existing
      BlockMap::iterator mi = mapBlockIndex.find(hash);
      if (mi != mapBlockIndex.end())
          return (*mi).second;
  
      // Create new
      CBlockIndex* pindexNew = new CBlockIndex();
      if (!pindexNew)
          throw runtime_error("LoadBlockIndex() : new CBlockIndex failed");
      mi = mapBlockIndex.insert(make_pair(hash, pindexNew)).first;
  
      //mark as PoS seen
      if (pindexNew->IsProofOfStake())
          setStakeSeen.insert(make_pair(pindexNew->prevoutStake, pindexNew->nStakeTime));
  
      pindexNew->phashBlock = &((*mi).first);
  
      return pindexNew;
  }
  
  bool static LoadBlockIndexDB()
  {
      if (!pblocktree->LoadBlockIndexGuts())
          return false;
  
      boost::this_thread::interruption_point();
  
      // Calculate nChainWork
      vector<pair<int, CBlockIndex*> > vSortedByHeight;
      vSortedByHeight.reserve(mapBlockIndex.size());
      BOOST_FOREACH (const PAIRTYPE(uint256, CBlockIndex*) & item, mapBlockIndex) {
          CBlockIndex* pindex = item.second;
          vSortedByHeight.push_back(make_pair(pindex->nHeight, pindex));
      }
      sort(vSortedByHeight.begin(), vSortedByHeight.end());
      BOOST_FOREACH (const PAIRTYPE(int, CBlockIndex*) & item, vSortedByHeight) {
          CBlockIndex* pindex = item.second;
          pindex->nChainWork = (pindex->pprev ? pindex->pprev->nChainWork : 0) + GetBlockProof(*pindex);
          if (pindex->nStatus & BLOCK_HAVE_DATA) {
              if (pindex->pprev) {
                  if (pindex->pprev->nChainTx) {
                      pindex->nChainTx = pindex->pprev->nChainTx + pindex->nTx;
                  } else {
                      pindex->nChainTx = 0;
                      mapBlocksUnlinked.insert(std::make_pair(pindex->pprev, pindex));
                  }
              } else {
                  pindex->nChainTx = pindex->nTx;
              }
          }
          if (pindex->IsValid(BLOCK_VALID_TRANSACTIONS) && (pindex->nChainTx || pindex->pprev == NULL))
              setBlockIndexCandidates.insert(pindex);
          if (pindex->nStatus & BLOCK_FAILED_MASK && (!pindexBestInvalid || pindex->nChainWork > pindexBestInvalid->nChainWork))
              pindexBestInvalid = pindex;
          if (pindex->pprev)
              pindex->BuildSkip();
          if (pindex->IsValid(BLOCK_VALID_TREE) && (pindexBestHeader == NULL || CBlockIndexWorkComparator()(pindexBestHeader, pindex)))
              pindexBestHeader = pindex;
      }
  
      // Load block file info
      pblocktree->ReadLastBlockFile(nLastBlockFile);
      vinfoBlockFile.resize(nLastBlockFile + 1);
      LogPrintf("%s: last block file = %i\n", __func__, nLastBlockFile);
      for (int nFile = 0; nFile <= nLastBlockFile; nFile++) {
          pblocktree->ReadBlockFileInfo(nFile, vinfoBlockFile[nFile]);
      }
      LogPrintf("%s: last block file info: %s\n", __func__, vinfoBlockFile[nLastBlockFile].ToString());
      for (int nFile = nLastBlockFile + 1; true; nFile++) {
          CBlockFileInfo info;
          if (pblocktree->ReadBlockFileInfo(nFile, info)) {
              vinfoBlockFile.push_back(info);
          } else {
              break;
          }
      }
  
      // Check presence of blk files
      LogPrintf("Checking all blk files are present...\n");
      set<int> setBlkDataFiles;
      BOOST_FOREACH (const PAIRTYPE(uint256, CBlockIndex*) & item, mapBlockIndex) {
          CBlockIndex* pindex = item.second;
          if (pindex->nStatus & BLOCK_HAVE_DATA) {
              setBlkDataFiles.insert(pindex->nFile);
          }
      }
      for (std::set<int>::iterator it = setBlkDataFiles.begin(); it != setBlkDataFiles.end(); it++) {
          CDiskBlockPos pos(*it, 0);
          if (CAutoFile(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION).IsNull()) {
              return false;
          }
      }
  
      //Check if the shutdown procedure was followed on last client exit
      bool fLastShutdownWasPrepared = true;
      pblocktree->ReadFlag("shutdown", fLastShutdownWasPrepared);
      LogPrintf("%s: Last shutdown was prepared: %s\n", __func__, fLastShutdownWasPrepared);
  
      //Check for inconsistency with block file info and internal state
      if (!fLastShutdownWasPrepared && !GetBoolArg("-forcestart", false) && !GetBoolArg("-reindex", false) && (vSortedByHeight.size() != vinfoBlockFile[nLastBlockFile].nHeightLast + 1) && (vinfoBlockFile[nLastBlockFile].nHeightLast != 0)) {
          //The database is in a state where a block has been accepted and written to disk, but not
          //all of the block has perculated through the code. The block and the index should both be
          //intact (although assertions are added if they are not), and the block will be reprocessed
          //to ensure all data will be accounted for.
          LogPrintf("%s: Inconsistent State Detected mapBlockIndex.size()=%d blockFileBlocks=%d\n", __func__, vSortedByHeight.size(), vinfoBlockFile[nLastBlockFile].nHeightLast + 1);
          LogPrintf("%s: lastIndexPos=%d blockFileSize=%d\n", __func__, vSortedByHeight[vSortedByHeight.size() - 1].second->GetBlockPos().nPos,
              vinfoBlockFile[nLastBlockFile].nSize);
  
          //try reading the block from the last index we have
          bool isFixed = true;
          string strError = "";
          LogPrintf("%s: Attempting to re-add last block that was recorded to disk\n", __func__);
  
          //get the last block that was properly recorded to the block info file
          CBlockIndex* pindexLastMeta = vSortedByHeight[vinfoBlockFile[nLastBlockFile].nHeightLast + 1].second;
  
          //fix Assertion `hashPrevBlock == view.GetBestBlock()' failed. By adjusting height to the last recorded by coinsview
          CBlockIndex* pindexCoinsView = mapBlockIndex[pcoinsTip->GetBestBlock()];
          for(unsigned int i = vinfoBlockFile[nLastBlockFile].nHeightLast + 1; i < vSortedByHeight.size(); i++)
          {
              pindexLastMeta = vSortedByHeight[i].second;
              if(pindexLastMeta->nHeight > pindexCoinsView->nHeight)
                  break;
          }
  
          LogPrintf("%s: Last block properly recorded: #%d %s\n", __func__, pindexLastMeta->nHeight, pindexLastMeta->GetBlockHash().ToString().c_str());
  
          CBlock lastMetaBlock;
          if (!ReadBlockFromDisk(lastMetaBlock, pindexLastMeta)) {
              isFixed = false;
              strError = strprintf("failed to read block %d from disk", pindexLastMeta->nHeight);
          }
  
          //set the chain to the block before lastMeta so that the meta block will be seen as new
          chainActive.SetTip(pindexLastMeta->pprev);
  
          //Process the lastMetaBlock again, using the known location on disk
          CDiskBlockPos blockPos = pindexLastMeta->GetBlockPos();
          CValidationState state;
          ProcessNewBlock(state, NULL, &lastMetaBlock, &blockPos);
  
          //ensure that everything is as it should be
          if (pcoinsTip->GetBestBlock() != vSortedByHeight[vSortedByHeight.size() - 1].second->GetBlockHash()) {
              isFixed = false;
              strError = "pcoinsTip best block is not correct";
          }
  
          //properly account for all of the blocks that were not in the meta data. If this is not done the file
          //positioning will be wrong and blocks will be overwritten and later cause serialization errors
          CBlockIndex *pindexLast = vSortedByHeight[vSortedByHeight.size() - 1].second;
          CBlock lastBlock;
          if (!ReadBlockFromDisk(lastBlock, pindexLast)) {
              isFixed = false;
              strError = strprintf("failed to read block %d from disk", pindexLast->nHeight);
          }
          vinfoBlockFile[nLastBlockFile].nHeightLast = pindexLast->nHeight;
          vinfoBlockFile[nLastBlockFile].nSize = pindexLast->GetBlockPos().nPos + ::GetSerializeSize(lastBlock, SER_DISK, CLIENT_VERSION);;
          setDirtyFileInfo.insert(nLastBlockFile);
          FlushStateToDisk(state, FLUSH_STATE_ALWAYS);
  
          //Print out file info again
          pblocktree->ReadLastBlockFile(nLastBlockFile);
          vinfoBlockFile.resize(nLastBlockFile + 1);
          LogPrintf("%s: last block file = %i\n", __func__, nLastBlockFile);
          for (int nFile = 0; nFile <= nLastBlockFile; nFile++) {
              pblocktree->ReadBlockFileInfo(nFile, vinfoBlockFile[nFile]);
          }
          LogPrintf("%s: last block file info: %s\n", __func__, vinfoBlockFile[nLastBlockFile].ToString());
  
          if (!isFixed) {
              strError = "Failed reading from database. " + strError + ". The block database is in an inconsistent state and may cause issues in the future."
                                                                       "To force start use -forcestart";
              uiInterface.ThreadSafeMessageBox(strError, "", CClientUIInterface::MSG_ERROR);
              abort();
          }
          LogPrintf("Passed corruption fix\n");
      }
  
      // Check whether we need to continue reindexing
      bool fReindexing = false;
      pblocktree->ReadReindexing(fReindexing);
      fReindex |= fReindexing;
  
      // Check whether we have a transaction index
      pblocktree->ReadFlag("txindex", fTxIndex);
      LogPrintf("LoadBlockIndexDB(): transaction index %s\n", fTxIndex ? "enabled" : "disabled");
  
      // If this is written true before the next client init, then we know the shutdown process failed
      pblocktree->WriteFlag("shutdown", false);
  
      // Load pointer to end of best chain
      BlockMap::iterator it = mapBlockIndex.find(pcoinsTip->GetBestBlock());
      if (it == mapBlockIndex.end())
          return true;
      chainActive.SetTip(it->second);
  
      PruneBlockIndexCandidates();
  
      LogPrintf("LoadBlockIndexDB(): hashBestChain=%s height=%d date=%s progress=%f\n",
          chainActive.Tip()->GetBlockHash().ToString(), chainActive.Height(),
          DateTimeStrFormat("%Y-%m-%d %H:%M:%S", chainActive.Tip()->GetBlockTime()),
          Checkpoints::GuessVerificationProgress(chainActive.Tip()));
  
      return true;
  }
  
  CVerifyDB::CVerifyDB()
  {
      uiInterface.ShowProgress(_("Verifying blocks..."), 0);
  }
  
  CVerifyDB::~CVerifyDB()
  {
      uiInterface.ShowProgress("", 100);
  }
  
  bool CVerifyDB::VerifyDB(CCoinsView* coinsview, int nCheckLevel, int nCheckDepth)
  {
      LOCK(cs_main);
      if (chainActive.Tip() == NULL || chainActive.Tip()->pprev == NULL)
          return true;
  
      // Verify blocks in the best chain
      if (nCheckDepth <= 0)
          nCheckDepth = 1000000000; // suffices until the year 19000
      if (nCheckDepth > chainActive.Height())
          nCheckDepth = chainActive.Height();
      nCheckLevel = std::max(0, std::min(4, nCheckLevel));
      LogPrintf("Verifying last %i blocks at level %i\n", nCheckDepth, nCheckLevel);
      CCoinsViewCache coins(coinsview);
      CBlockIndex* pindexState = chainActive.Tip();
      CBlockIndex* pindexFailure = NULL;
      int nGoodTransactions = 0;
      CValidationState state;
      for (CBlockIndex* pindex = chainActive.Tip(); pindex && pindex->pprev; pindex = pindex->pprev) {
          boost::this_thread::interruption_point();
          uiInterface.ShowProgress(_("Verifying blocks..."), std::max(1, std::min(99, (int)(((double)(chainActive.Height() - pindex->nHeight)) / (double)nCheckDepth * (nCheckLevel >= 4 ? 50 : 100)))));
          if (pindex->nHeight < chainActive.Height() - nCheckDepth)
              break;
          CBlock block;
          // check level 0: read from disk
          if (!ReadBlockFromDisk(block, pindex))
              return error("VerifyDB() : *** ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
          // check level 1: verify block validity
          if (nCheckLevel >= 1 && !CheckBlock(block, state))
              return error("VerifyDB() : *** found bad block at %d, hash=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
          // check level 2: verify undo validity
          if (nCheckLevel >= 2 && pindex) {
              CBlockUndo undo;
              CDiskBlockPos pos = pindex->GetUndoPos();
              if (!pos.IsNull()) {
                  if (!undo.ReadFromDisk(pos, pindex->pprev->GetBlockHash()))
                      return error("VerifyDB() : *** found bad undo data at %d, hash=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
              }
          }
          // check level 3: check for inconsistencies during memory-only disconnect of tip blocks
          if (nCheckLevel >= 3 && pindex == pindexState && (coins.GetCacheSize() + pcoinsTip->GetCacheSize()) <= nCoinCacheSize) {
              bool fClean = true;
              if (!DisconnectBlock(block, state, pindex, coins, &fClean))
                  return error("VerifyDB() : *** irrecoverable inconsistency in block data at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
              pindexState = pindex->pprev;
              if (!fClean) {
                  nGoodTransactions = 0;
                  pindexFailure = pindex;
              } else
                  nGoodTransactions += block.vtx.size();
          }
          if (ShutdownRequested())
              return true;
      }
      if (pindexFailure)
          return error("VerifyDB() : *** coin database inconsistencies found (last %i blocks, %i good transactions before that)\n", chainActive.Height() - pindexFailure->nHeight + 1, nGoodTransactions);
  
      // check level 4: try reconnecting blocks
      if (nCheckLevel >= 4) {
          CBlockIndex* pindex = pindexState;
          while (pindex != chainActive.Tip()) {
              boost::this_thread::interruption_point();
              uiInterface.ShowProgress(_("Verifying blocks..."), std::max(1, std::min(99, 100 - (int)(((double)(chainActive.Height() - pindex->nHeight)) / (double)nCheckDepth * 50))));
              pindex = chainActive.Next(pindex);
              CBlock block;
              if (!ReadBlockFromDisk(block, pindex))
                  return error("VerifyDB() : *** ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
              if (!ConnectBlock(block, state, pindex, coins))
                  return error("VerifyDB() : *** found unconnectable block at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
          }
      }
  
      LogPrintf("No coin database inconsistencies in last %i blocks (%i transactions)\n", chainActive.Height() - pindexState->nHeight, nGoodTransactions);
  
      return true;
  }
  
  void UnloadBlockIndex()
  {
      mapBlockIndex.clear();
      setBlockIndexCandidates.clear();
      chainActive.SetTip(NULL);
      pindexBestInvalid = NULL;
  }
  
  bool LoadBlockIndex()
  {
      // Load block index from databases
      if (!fReindex && !LoadBlockIndexDB())
          return false;
      return true;
  }
  
  
  bool InitBlockIndex()
  {
      LOCK(cs_main);
      // Check whether we're already initialized
      if (chainActive.Genesis() != NULL)
          return true;
  
      // Use the provided setting for -txindex in the new database
      fTxIndex = GetBoolArg("-txindex", true);
      pblocktree->WriteFlag("txindex", fTxIndex);
      LogPrintf("Initializing databases...\n");
  
      // Only add the genesis block if not reindexing (in which case we reuse the one already on disk)
      if (!fReindex) {
          try {
              CBlock& block = const_cast<CBlock&>(Params().GenesisBlock());
              // Start new block file
              unsigned int nBlockSize = ::GetSerializeSize(block, SER_DISK, CLIENT_VERSION);
              CDiskBlockPos blockPos;
              CValidationState state;
              if (!FindBlockPos(state, blockPos, nBlockSize + 8, 0, block.GetBlockTime()))
                  return error("LoadBlockIndex() : FindBlockPos failed");
              if (!WriteBlockToDisk(block, blockPos))
                  return error("LoadBlockIndex() : writing genesis block to disk failed");
              CBlockIndex* pindex = AddToBlockIndex(block);
              if (!ReceivedBlockTransactions(block, state, pindex, blockPos))
                  return error("LoadBlockIndex() : genesis block not accepted");
              if (!ActivateBestChain(state, &block))
                  return error("LoadBlockIndex() : genesis block cannot be activated");
              // Force a chainstate write so that when we VerifyDB in a moment, it doesnt check stale data
              return FlushStateToDisk(state, FLUSH_STATE_ALWAYS);
          } catch (std::runtime_error& e) {
              return error("LoadBlockIndex() : failed to initialize block database: %s", e.what());
          }
      }
  
      return true;
  }
  
  
  bool LoadExternalBlockFile(FILE* fileIn, CDiskBlockPos* dbp)
  {
      // Map of disk positions for blocks with unknown parent (only used for reindex)
      static std::multimap<uint256, CDiskBlockPos> mapBlocksUnknownParent;
      int64_t nStart = GetTimeMillis();
  
      int nLoaded = 0;
      try {
          // This takes over fileIn and calls fclose() on it in the CBufferedFile destructor
          CBufferedFile blkdat(fileIn, 2 * MAX_BLOCK_SIZE, MAX_BLOCK_SIZE + 8, SER_DISK, CLIENT_VERSION);
          uint64_t nRewind = blkdat.GetPos();
          while (!blkdat.eof()) {
              boost::this_thread::interruption_point();
  
              blkdat.SetPos(nRewind);
              nRewind++;         // start one byte further next time, in case of failure
              blkdat.SetLimit(); // remove former limit
              unsigned int nSize = 0;
              try {
                  // locate a header
                  unsigned char buf[MESSAGE_START_SIZE];
                  blkdat.FindByte(Params().MessageStart()[0]);
                  nRewind = blkdat.GetPos() + 1;
                  blkdat >> FLATDATA(buf);
                  if (memcmp(buf, Params().MessageStart(), MESSAGE_START_SIZE))
                      continue;
                  // read size
                  blkdat >> nSize;
                  if (nSize < 80 || nSize > MAX_BLOCK_SIZE)
                      continue;
              } catch (const std::exception&) {
                  // no valid block header found; don't complain
                  break;
              }
              try {
                  // read block
                  uint64_t nBlockPos = blkdat.GetPos();
                  if (dbp)
                      dbp->nPos = nBlockPos;
                  blkdat.SetLimit(nBlockPos + nSize);
                  blkdat.SetPos(nBlockPos);
                  CBlock block;
                  blkdat >> block;
                  nRewind = blkdat.GetPos();
  
                  // detect out of order blocks, and store them for later
                  uint256 hash = block.GetHash();
                  if (hash != Params().HashGenesisBlock() && mapBlockIndex.find(block.hashPrevBlock) == mapBlockIndex.end()) {
                      LogPrint("reindex", "%s: Out of order block %s, parent %s not known\n", __func__, hash.ToString(),
                          block.hashPrevBlock.ToString());
                      if (dbp)
                          mapBlocksUnknownParent.insert(std::make_pair(block.hashPrevBlock, *dbp));
                      continue;
                  }
  
                  // process in case the block isn't known yet
                  if (mapBlockIndex.count(hash) == 0 || (mapBlockIndex[hash]->nStatus & BLOCK_HAVE_DATA) == 0) {
                      CValidationState state;
                      if (ProcessNewBlock(state, NULL, &block, dbp))
                          nLoaded++;
                      if (state.IsError())
                          break;
                  } else if (hash != Params().HashGenesisBlock() && mapBlockIndex[hash]->nHeight % 1000 == 0) {
                      LogPrintf("Block Import: already had block %s at height %d\n", hash.ToString(), mapBlockIndex[hash]->nHeight);
                  }
  
                  // Recursively process earlier encountered successors of this block
                  deque<uint256> queue;
                  queue.push_back(hash);
                  while (!queue.empty()) {
                      uint256 head = queue.front();
                      queue.pop_front();
                      std::pair<std::multimap<uint256, CDiskBlockPos>::iterator, std::multimap<uint256, CDiskBlockPos>::iterator> range = mapBlocksUnknownParent.equal_range(head);
                      while (range.first != range.second) {
                          std::multimap<uint256, CDiskBlockPos>::iterator it = range.first;
                          if (ReadBlockFromDisk(block, it->second)) {
                              LogPrintf("%s: Processing out of order child %s of %s\n", __func__, block.GetHash().ToString(),
                                  head.ToString());
                              CValidationState dummy;
                              if (ProcessNewBlock(dummy, NULL, &block, &it->second)) {
                                  nLoaded++;
                                  queue.push_back(block.GetHash());
                              }
                          }
                          range.first++;
                          mapBlocksUnknownParent.erase(it);
                      }
                  }
              } catch (std::exception& e) {
                  LogPrintf("%s : Deserialize or I/O error - %s", __func__, e.what());
              }
          }
      } catch (std::runtime_error& e) {
          AbortNode(std::string("System error: ") + e.what());
      }
      if (nLoaded > 0)
          LogPrintf("Loaded %i blocks from external file in %dms\n", nLoaded, GetTimeMillis() - nStart);
      return nLoaded > 0;
  }
  
  void static CheckBlockIndex()
  {
      if (!fCheckBlockIndex) {
          return;
      }
  
      LOCK(cs_main);
  
      // During a reindex, we read the genesis block and call CheckBlockIndex before ActivateBestChain,
      // so we have the genesis block in mapBlockIndex but no active chain.  (A few of the tests when
      // iterating the block tree require that chainActive has been initialized.)
      if (chainActive.Height() < 0) {
          assert(mapBlockIndex.size() <= 1);
          return;
      }
  
      // Build forward-pointing map of the entire block tree.
      std::multimap<CBlockIndex*, CBlockIndex*> forward;
      for (BlockMap::iterator it = mapBlockIndex.begin(); it != mapBlockIndex.end(); it++) {
          forward.insert(std::make_pair(it->second->pprev, it->second));
      }
  
      assert(forward.size() == mapBlockIndex.size());
  
      std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> rangeGenesis = forward.equal_range(NULL);
      CBlockIndex* pindex = rangeGenesis.first->second;
      rangeGenesis.first++;
      assert(rangeGenesis.first == rangeGenesis.second); // There is only one index entry with parent NULL.
  
      // Iterate over the entire block tree, using depth-first search.
      // Along the way, remember whether there are blocks on the path from genesis
      // block being explored which are the first to have certain properties.
      size_t nNodes = 0;
      int nHeight = 0;
      CBlockIndex* pindexFirstInvalid = NULL;         // Oldest ancestor of pindex which is invalid.
      CBlockIndex* pindexFirstMissing = NULL;         // Oldest ancestor of pindex which does not have BLOCK_HAVE_DATA.
      CBlockIndex* pindexFirstNotTreeValid = NULL;    // Oldest ancestor of pindex which does not have BLOCK_VALID_TREE (regardless of being valid or not).
      CBlockIndex* pindexFirstNotChainValid = NULL;   // Oldest ancestor of pindex which does not have BLOCK_VALID_CHAIN (regardless of being valid or not).
      CBlockIndex* pindexFirstNotScriptsValid = NULL; // Oldest ancestor of pindex which does not have BLOCK_VALID_SCRIPTS (regardless of being valid or not).
      while (pindex != NULL) {
          nNodes++;
          if (pindexFirstInvalid == NULL && pindex->nStatus & BLOCK_FAILED_VALID) pindexFirstInvalid = pindex;
          if (pindexFirstMissing == NULL && !(pindex->nStatus & BLOCK_HAVE_DATA)) pindexFirstMissing = pindex;
          if (pindex->pprev != NULL && pindexFirstNotTreeValid == NULL && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TREE) pindexFirstNotTreeValid = pindex;
          if (pindex->pprev != NULL && pindexFirstNotChainValid == NULL && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_CHAIN) pindexFirstNotChainValid = pindex;
          if (pindex->pprev != NULL && pindexFirstNotScriptsValid == NULL && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_SCRIPTS) pindexFirstNotScriptsValid = pindex;
  
          // Begin: actual consistency checks.
          if (pindex->pprev == NULL) {
              // Genesis block checks.
              assert(pindex->GetBlockHash() == Params().HashGenesisBlock()); // Genesis block's hash must match.
              assert(pindex == chainActive.Genesis());                       // The current active chain's genesis block must be this block.
          }
          // HAVE_DATA is equivalent to VALID_TRANSACTIONS and equivalent to nTx > 0 (we stored the number of transactions in the block)
          assert(!(pindex->nStatus & BLOCK_HAVE_DATA) == (pindex->nTx == 0));
          assert(((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TRANSACTIONS) == (pindex->nTx > 0));
          if (pindex->nChainTx == 0) assert(pindex->nSequenceId == 0); // nSequenceId can't be set for blocks that aren't linked
          // All parents having data is equivalent to all parents being VALID_TRANSACTIONS, which is equivalent to nChainTx being set.
          assert((pindexFirstMissing != NULL) == (pindex->nChainTx == 0));                                             // nChainTx == 0 is used to signal that all parent block's transaction data is available.
          assert(pindex->nHeight == nHeight);                                                                          // nHeight must be consistent.
          assert(pindex->pprev == NULL || pindex->nChainWork >= pindex->pprev->nChainWork);                            // For every block except the genesis block, the chainwork must be larger than the parent's.
          assert(nHeight < 2 || (pindex->pskip && (pindex->pskip->nHeight < nHeight)));                                // The pskip pointer must point back for all but the first 2 blocks.
          assert(pindexFirstNotTreeValid == NULL);                                                                     // All mapBlockIndex entries must at least be TREE valid
          if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TREE) assert(pindexFirstNotTreeValid == NULL);       // TREE valid implies all parents are TREE valid
          if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_CHAIN) assert(pindexFirstNotChainValid == NULL);     // CHAIN valid implies all parents are CHAIN valid
          if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_SCRIPTS) assert(pindexFirstNotScriptsValid == NULL); // SCRIPTS valid implies all parents are SCRIPTS valid
          if (pindexFirstInvalid == NULL) {
              // Checks for not-invalid blocks.
              assert((pindex->nStatus & BLOCK_FAILED_MASK) == 0); // The failed mask cannot be set for blocks without invalid parents.
          }
          if (!CBlockIndexWorkComparator()(pindex, chainActive.Tip()) && pindexFirstMissing == NULL) {
              if (pindexFirstInvalid == NULL) { // If this block sorts at least as good as the current tip and is valid, it must be in setBlockIndexCandidates.
                  assert(setBlockIndexCandidates.count(pindex));
              }
          } else { // If this block sorts worse than the current tip, it cannot be in setBlockIndexCandidates.
              assert(setBlockIndexCandidates.count(pindex) == 0);
          }
          // Check whether this block is in mapBlocksUnlinked.
          std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> rangeUnlinked = mapBlocksUnlinked.equal_range(pindex->pprev);
          bool foundInUnlinked = false;
          while (rangeUnlinked.first != rangeUnlinked.second) {
              assert(rangeUnlinked.first->first == pindex->pprev);
              if (rangeUnlinked.first->second == pindex) {
                  foundInUnlinked = true;
                  break;
              }
              rangeUnlinked.first++;
          }
          if (pindex->pprev && pindex->nStatus & BLOCK_HAVE_DATA && pindexFirstMissing != NULL) {
              if (pindexFirstInvalid == NULL) { // If this block has block data available, some parent doesn't, and has no invalid parents, it must be in mapBlocksUnlinked.
                  assert(foundInUnlinked);
              }
          } else { // If this block does not have block data available, or all parents do, it cannot be in mapBlocksUnlinked.
              assert(!foundInUnlinked);
          }
          // assert(pindex->GetBlockHash() == pindex->GetBlockHeader().GetHash()); // Perhaps too slow
          // End: actual consistency checks.
  
          // Try descending into the first subnode.
          std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> range = forward.equal_range(pindex);
          if (range.first != range.second) {
              // A subnode was found.
              pindex = range.first->second;
              nHeight++;
              continue;
          }
          // This is a leaf node.
          // Move upwards until we reach a node of which we have not yet visited the last child.
          while (pindex) {
              // We are going to either move to a parent or a sibling of pindex.
              // If pindex was the first with a certain property, unset the corresponding variable.
              if (pindex == pindexFirstInvalid) pindexFirstInvalid = NULL;
              if (pindex == pindexFirstMissing) pindexFirstMissing = NULL;
              if (pindex == pindexFirstNotTreeValid) pindexFirstNotTreeValid = NULL;
              if (pindex == pindexFirstNotChainValid) pindexFirstNotChainValid = NULL;
              if (pindex == pindexFirstNotScriptsValid) pindexFirstNotScriptsValid = NULL;
              // Find our parent.
              CBlockIndex* pindexPar = pindex->pprev;
              // Find which child we just visited.
              std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> rangePar = forward.equal_range(pindexPar);
              while (rangePar.first->second != pindex) {
                  assert(rangePar.first != rangePar.second); // Our parent must have at least the node we're coming from as child.
                  rangePar.first++;
              }
              // Proceed to the next one.
              rangePar.first++;
              if (rangePar.first != rangePar.second) {
                  // Move to the sibling.
                  pindex = rangePar.first->second;
                  break;
              } else {
                  // Move up further.
                  pindex = pindexPar;
                  nHeight--;
                  continue;
              }
          }
      }
  
      // Check that we actually traversed the entire map.
      assert(nNodes == forward.size());
  }
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // CAlert
  //
  
  string GetWarnings(string strFor)
  {
      int nPriority = 0;
      string strStatusBar;
      string strRPC;
  
      if (!CLIENT_VERSION_IS_RELEASE)
          strStatusBar = _("This is a pre-release test build - use at your own risk - do not use for mining or merchant applications");
  
      if (GetBoolArg("-testsafemode", false))
          strStatusBar = strRPC = "testsafemode enabled";
  
      // Misc warnings like out of disk space and clock is wrong
      if (strMiscWarning != "") {
          nPriority = 1000;
          strStatusBar = strMiscWarning;
      }
  
      if (fLargeWorkForkFound) {
          nPriority = 2000;
          strStatusBar = strRPC = _("Warning: The network does not appear to fully agree! Some miners appear to be experiencing issues.");
      } else if (fLargeWorkInvalidChainFound) {
          nPriority = 2000;
          strStatusBar = strRPC = _("Warning: We do not appear to fully agree with our peers! You may need to upgrade, or other nodes may need to upgrade.");
      }
  
      // Alerts
      {
          LOCK(cs_mapAlerts);
          BOOST_FOREACH (PAIRTYPE(const uint256, CAlert) & item, mapAlerts) {
              const CAlert& alert = item.second;
              if (alert.AppliesToMe() && alert.nPriority > nPriority) {
                  nPriority = alert.nPriority;
                  strStatusBar = alert.strStatusBar;
              }
          }
      }
  
      if (strFor == "statusbar")
          return strStatusBar;
      else if (strFor == "rpc")
          return strRPC;
      assert(!"GetWarnings() : invalid parameter");
      return "error";
  }
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // Messages
  //
  
  
  bool static AlreadyHave(const CInv& inv)
  {
      switch (inv.type) {
      case MSG_TX: {
          bool txInMap = false;
          txInMap = mempool.exists(inv.hash);
          return txInMap || mapOrphanTransactions.count(inv.hash) ||
                 pcoinsTip->HaveCoins(inv.hash);
      }
      case MSG_DSTX:
          return mapObfuscationBroadcastTxes.count(inv.hash);
      case MSG_BLOCK:
          return mapBlockIndex.count(inv.hash);
      case MSG_TXLOCK_REQUEST:
          return mapTxLockReq.count(inv.hash) ||
                 mapTxLockReqRejected.count(inv.hash);
      case MSG_TXLOCK_VOTE:
          return mapTxLockVote.count(inv.hash);
      case MSG_SPORK:
          return mapSporks.count(inv.hash);
      case MSG_MASTERNODE_WINNER:
          if (masternodePayments.mapMasternodePayeeVotes.count(inv.hash)) {
              masternodeSync.AddedMasternodeWinner(inv.hash);
              return true;
          }
          return false;
      case MSG_BUDGET_VOTE:
          if (budget.mapSeenMasternodeBudgetVotes.count(inv.hash)) {
              masternodeSync.AddedBudgetItem(inv.hash);
              return true;
          }
          return false;
      case MSG_BUDGET_PROPOSAL:
          if (budget.mapSeenMasternodeBudgetProposals.count(inv.hash)) {
              masternodeSync.AddedBudgetItem(inv.hash);
              return true;
          }
          return false;
      case MSG_BUDGET_FINALIZED_VOTE:
          if (budget.mapSeenFinalizedBudgetVotes.count(inv.hash)) {
              masternodeSync.AddedBudgetItem(inv.hash);
              return true;
          }
          return false;
      case MSG_BUDGET_FINALIZED:
          if (budget.mapSeenFinalizedBudgets.count(inv.hash)) {
              masternodeSync.AddedBudgetItem(inv.hash);
              return true;
          }
          return false;
      case MSG_MASTERNODE_ANNOUNCE:
          if (mnodeman.mapSeenMasternodeBroadcast.count(inv.hash)) {
              masternodeSync.AddedMasternodeList(inv.hash);
              return true;
          }
          return false;
      case MSG_MASTERNODE_PING:
          return mnodeman.mapSeenMasternodePing.count(inv.hash);
      }
      // Don't know what it is, just say we already got one
      return true;
  }
  
  
  void static ProcessGetData(CNode* pfrom)
  {
      std::deque<CInv>::iterator it = pfrom->vRecvGetData.begin();
  
      vector<CInv> vNotFound;
  
      LOCK(cs_main);
  
      while (it != pfrom->vRecvGetData.end()) {
          // Don't bother if send buffer is too full to respond anyway
          if (pfrom->nSendSize >= SendBufferSize())
              break;
  
          const CInv& inv = *it;
          {
              boost::this_thread::interruption_point();
              it++;
  
              if (inv.type == MSG_BLOCK || inv.type == MSG_FILTERED_BLOCK) {
                  bool send = false;
                  BlockMap::iterator mi = mapBlockIndex.find(inv.hash);
                  if (mi != mapBlockIndex.end()) {
                      if (chainActive.Contains(mi->second)) {
                          send = true;
                      } else {
                          // To prevent fingerprinting attacks, only send blocks outside of the active
                          // chain if they are valid, and no more than a max reorg depth than the best header
                          // chain we know about.
                          send = mi->second->IsValid(BLOCK_VALID_SCRIPTS) && (pindexBestHeader != NULL) &&
                                 (chainActive.Height() - mi->second->nHeight < Params().MaxReorganizationDepth());
                          if (!send) {
                              LogPrintf("ProcessGetData(): ignoring request from peer=%i for old block that isn't in the main chain\n", pfrom->GetId());
                          }
                      }
                  }
                  if (send) {
                      // Send block from disk
                      CBlock block;
                      if (!ReadBlockFromDisk(block, (*mi).second))
                          assert(!"cannot load block from disk");
                      if (inv.type == MSG_BLOCK)
                          pfrom->PushMessage("block", block);
                      else // MSG_FILTERED_BLOCK)
                      {
                          LOCK(pfrom->cs_filter);
                          if (pfrom->pfilter) {
                              CMerkleBlock merkleBlock(block, *pfrom->pfilter);
                              pfrom->PushMessage("merkleblock", merkleBlock);
                              // CMerkleBlock just contains hashes, so also push any transactions in the block the client did not see
                              // This avoids hurting performance by pointlessly requiring a round-trip
                              // Note that there is currently no way for a node to request any single transactions we didnt send here -
                              // they must either disconnect and retry or request the full block.
                              // Thus, the protocol spec specified allows for us to provide duplicate txn here,
                              // however we MUST always provide at least what the remote peer needs
                              typedef std::pair<unsigned int, uint256> PairType;
                              BOOST_FOREACH (PairType& pair, merkleBlock.vMatchedTxn)
                                  if (!pfrom->setInventoryKnown.count(CInv(MSG_TX, pair.second)))
                                      pfrom->PushMessage("tx", block.vtx[pair.first]);
                          }
                          // else
                          // no response
                      }
  
                      // Trigger them to send a getblocks request for the next batch of inventory
                      if (inv.hash == pfrom->hashContinue) {
                          // Bypass PushInventory, this must send even if redundant,
                          // and we want it right after the last block so they don't
                          // wait for other stuff first.
                          vector<CInv> vInv;
                          vInv.push_back(CInv(MSG_BLOCK, chainActive.Tip()->GetBlockHash()));
                          pfrom->PushMessage("inv", vInv);
                          pfrom->hashContinue = 0;
                      }
                  }
              } else if (inv.IsKnownType()) {
                  // Send stream from relay memory
                  bool pushed = false;
                  {
                      LOCK(cs_mapRelay);
                      map<CInv, CDataStream>::iterator mi = mapRelay.find(inv);
                      if (mi != mapRelay.end()) {
                          pfrom->PushMessage(inv.GetCommand(), (*mi).second);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_TX) {
                      CTransaction tx;
                      if (mempool.lookup(inv.hash, tx)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << tx;
                          pfrom->PushMessage("tx", ss);
                          pushed = true;
                      }
                  }
                  if (!pushed && inv.type == MSG_TXLOCK_VOTE) {
                      if (mapTxLockVote.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << mapTxLockVote[inv.hash];
                          pfrom->PushMessage("txlvote", ss);
                          pushed = true;
                      }
                  }
                  if (!pushed && inv.type == MSG_TXLOCK_REQUEST) {
                      if (mapTxLockReq.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << mapTxLockReq[inv.hash];
                          pfrom->PushMessage("ix", ss);
                          pushed = true;
                      }
                  }
                  if (!pushed && inv.type == MSG_SPORK) {
                      if (mapSporks.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << mapSporks[inv.hash];
                          pfrom->PushMessage("spork", ss);
                          pushed = true;
                      }
                  }
                  if (!pushed && inv.type == MSG_MASTERNODE_WINNER) {
                      if (masternodePayments.mapMasternodePayeeVotes.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << masternodePayments.mapMasternodePayeeVotes[inv.hash];
                          pfrom->PushMessage("mnw", ss);
                          pushed = true;
                      }
                  }
                  if (!pushed && inv.type == MSG_BUDGET_VOTE) {
                      if (budget.mapSeenMasternodeBudgetVotes.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << budget.mapSeenMasternodeBudgetVotes[inv.hash];
                          pfrom->PushMessage("mvote", ss);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_BUDGET_PROPOSAL) {
                      if (budget.mapSeenMasternodeBudgetProposals.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << budget.mapSeenMasternodeBudgetProposals[inv.hash];
                          pfrom->PushMessage("mprop", ss);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_BUDGET_FINALIZED_VOTE) {
                      if (budget.mapSeenFinalizedBudgetVotes.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << budget.mapSeenFinalizedBudgetVotes[inv.hash];
                          pfrom->PushMessage("fbvote", ss);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_BUDGET_FINALIZED) {
                      if (budget.mapSeenFinalizedBudgets.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << budget.mapSeenFinalizedBudgets[inv.hash];
                          pfrom->PushMessage("fbs", ss);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_MASTERNODE_ANNOUNCE) {
                      if (mnodeman.mapSeenMasternodeBroadcast.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << mnodeman.mapSeenMasternodeBroadcast[inv.hash];
                          pfrom->PushMessage("mnb", ss);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_MASTERNODE_PING) {
                      if (mnodeman.mapSeenMasternodePing.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << mnodeman.mapSeenMasternodePing[inv.hash];
                          pfrom->PushMessage("mnp", ss);
                          pushed = true;
                      }
                  }
  
                  if (!pushed && inv.type == MSG_DSTX) {
                      if (mapObfuscationBroadcastTxes.count(inv.hash)) {
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << mapObfuscationBroadcastTxes[inv.hash].tx << mapObfuscationBroadcastTxes[inv.hash].vin << mapObfuscationBroadcastTxes[inv.hash].vchSig << mapObfuscationBroadcastTxes[inv.hash].sigTime;
  
                          pfrom->PushMessage("dstx", ss);
                          pushed = true;
                      }
                  }
  
  
                  if (!pushed) {
                      vNotFound.push_back(inv);
                  }
              }
  
              // Track requests for our stuff.
              g_signals.Inventory(inv.hash);
  
              if (inv.type == MSG_BLOCK || inv.type == MSG_FILTERED_BLOCK)
                  break;
          }
      }
  
      pfrom->vRecvGetData.erase(pfrom->vRecvGetData.begin(), it);
  
      if (!vNotFound.empty()) {
          // Let the peer know that we didn't find what it asked for, so it doesn't
          // have to wait around forever. Currently only SPV clients actually care
          // about this message: it's needed when they are recursively walking the
          // dependencies of relevant unconfirmed transactions. SPV clients want to
          // do that because they want to know about (and store and rebroadcast and
          // risk analyze) the dependencies of transactions relevant to them, without
          // having to download the entire memory pool.
          pfrom->PushMessage("notfound", vNotFound);
      }
  }
  
  bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, int64_t nTimeReceived)
  {
      RandAddSeedPerfmon();
      if (fDebug)
          LogPrintf("received: %s (%u bytes) peer=%d\n", SanitizeString(strCommand), vRecv.size(), pfrom->id);
      if (mapArgs.count("-dropmessagestest") && GetRand(atoi(mapArgs["-dropmessagestest"])) == 0) {
          LogPrintf("dropmessagestest DROPPING RECV MESSAGE\n");
          return true;
      }
  
      if (strCommand == "version") {
          // Each connection can only send one version message
          if (pfrom->nVersion != 0) {
              pfrom->PushMessage("reject", strCommand, REJECT_DUPLICATE, string("Duplicate version message"));
              Misbehaving(pfrom->GetId(), 1);
              return false;
          }
  
          int64_t nTime;
          CAddress addrMe;
          CAddress addrFrom;
          uint64_t nNonce = 1;
          vRecv >> pfrom->nVersion >> pfrom->nServices >> nTime >> addrMe;
          if (pfrom->nVersion < ActiveProtocol()) {
              // disconnect from peers older than this proto version
              LogPrintf("peer=%d using obsolete version %i; disconnecting\n", pfrom->id, pfrom->nVersion);
              pfrom->PushMessage("reject", strCommand, REJECT_OBSOLETE,
                  strprintf("Version must be %d or greater", ActiveProtocol()));
              pfrom->fDisconnect = true;
              return false;
          }
  
          if (pfrom->nVersion == 10300)
              pfrom->nVersion = 300;
          if (!vRecv.empty())
              vRecv >> addrFrom >> nNonce;
          if (!vRecv.empty()) {
              vRecv >> LIMITED_STRING(pfrom->strSubVer, 256);
              pfrom->cleanSubVer = SanitizeString(pfrom->strSubVer);
          }
          if (!vRecv.empty())
              vRecv >> pfrom->nStartingHeight;
          if (!vRecv.empty())
              vRecv >> pfrom->fRelayTxes; // set to true after we get the first filter* message
          else
              pfrom->fRelayTxes = true;
  
          // Disconnect if we connected to ourself
          if (nNonce == nLocalHostNonce && nNonce > 1) {
              LogPrintf("connected to self at %s, disconnecting\n", pfrom->addr.ToString());
              pfrom->fDisconnect = true;
              return true;
          }
  
          pfrom->addrLocal = addrMe;
          if (pfrom->fInbound && addrMe.IsRoutable()) {
              SeenLocal(addrMe);
          }
  
          // Be shy and don't send version until we hear
          if (pfrom->fInbound)
              pfrom->PushVersion();
  
          pfrom->fClient = !(pfrom->nServices & NODE_NETWORK);
  
          // Potentially mark this peer as a preferred download peer.
          UpdatePreferredDownload(pfrom, State(pfrom->GetId()));
  
          // Change version
          pfrom->PushMessage("verack");
          pfrom->ssSend.SetVersion(min(pfrom->nVersion, PROTOCOL_VERSION));
  
          if (!pfrom->fInbound) {
              // Advertise our address
              if (fListen && !IsInitialBlockDownload()) {
                  CAddress addr = GetLocalAddress(&pfrom->addr);
                  if (addr.IsRoutable()) {
                      pfrom->PushAddress(addr);
                  } else if (IsPeerAddrLocalGood(pfrom)) {
                      addr.SetIP(pfrom->addrLocal);
                      pfrom->PushAddress(addr);
                  }
              }
  
              // Get recent addresses
              if (pfrom->fOneShot || pfrom->nVersion >= CADDR_TIME_VERSION || addrman.size() < 1000) {
                  pfrom->PushMessage("getaddr");
                  pfrom->fGetAddr = true;
              }
              addrman.Good(pfrom->addr);
          } else {
              if (((CNetAddr)pfrom->addr) == (CNetAddr)addrFrom) {
                  addrman.Add(addrFrom, addrFrom);
                  addrman.Good(addrFrom);
              }
          }
  
          // Relay alerts
          {
              LOCK(cs_mapAlerts);
              BOOST_FOREACH (PAIRTYPE(const uint256, CAlert) & item, mapAlerts)
                  item.second.RelayTo(pfrom);
          }
  
          pfrom->fSuccessfullyConnected = true;
  
          string remoteAddr;
          if (fLogIPs)
              remoteAddr = ", peeraddr=" + pfrom->addr.ToString();
  
          LogPrintf("receive version message: %s: version %d, blocks=%d, us=%s, peer=%d%s\n",
              pfrom->cleanSubVer, pfrom->nVersion,
              pfrom->nStartingHeight, addrMe.ToString(), pfrom->id,
              remoteAddr);
  
          AddTimeData(pfrom->addr, nTime);
      }
  
  
      else if (pfrom->nVersion == 0) {
          // Must have a version message before anything else
          Misbehaving(pfrom->GetId(), 1);
          return false;
      }
  
  
      else if (strCommand == "verack") {
          pfrom->SetRecvVersion(min(pfrom->nVersion, PROTOCOL_VERSION));
  
          // Mark this node as currently connected, so we update its timestamp later.
          if (pfrom->fNetworkNode) {
              LOCK(cs_main);
              State(pfrom->GetId())->fCurrentlyConnected = true;
          }
      }
  
  
      else if (strCommand == "addr") {
          vector<CAddress> vAddr;
          vRecv >> vAddr;
  
          // Don't want addr from older versions unless seeding
          if (pfrom->nVersion < CADDR_TIME_VERSION && addrman.size() > 1000)
              return true;
          if (vAddr.size() > 1000) {
              Misbehaving(pfrom->GetId(), 20);
              return error("message addr size() = %u", vAddr.size());
          }
  
          // Store the new addresses
          vector<CAddress> vAddrOk;
          int64_t nNow = GetAdjustedTime();
          int64_t nSince = nNow - 10 * 60;
          BOOST_FOREACH (CAddress& addr, vAddr) {
              boost::this_thread::interruption_point();
  
              if (addr.nTime <= 100000000 || addr.nTime > nNow + 10 * 60)
                  addr.nTime = nNow - 5 * 24 * 60 * 60;
              pfrom->AddAddressKnown(addr);
              bool fReachable = IsReachable(addr);
              if (addr.nTime > nSince && !pfrom->fGetAddr && vAddr.size() <= 10 && addr.IsRoutable()) {
                  // Relay to a limited number of other nodes
                  {
                      LOCK(cs_vNodes);
                      // Use deterministic randomness to send to the same nodes for 24 hours
                      // at a time so the setAddrKnowns of the chosen nodes prevent repeats
                      static uint256 hashSalt;
                      if (hashSalt == 0)
                          hashSalt = GetRandHash();
                      uint64_t hashAddr = addr.GetHash();
                      uint256 hashRand = hashSalt ^ (hashAddr << 32) ^ ((GetTime() + hashAddr) / (24 * 60 * 60));
                      hashRand = Hash(BEGIN(hashRand), END(hashRand));
                      multimap<uint256, CNode*> mapMix;
                      BOOST_FOREACH (CNode* pnode, vNodes) {
                          if (pnode->nVersion < CADDR_TIME_VERSION)
                              continue;
                          unsigned int nPointer;
                          memcpy(&nPointer, &pnode, sizeof(nPointer));
                          uint256 hashKey = hashRand ^ nPointer;
                          hashKey = Hash(BEGIN(hashKey), END(hashKey));
                          mapMix.insert(make_pair(hashKey, pnode));
                      }
                      int nRelayNodes = fReachable ? 2 : 1; // limited relaying of addresses outside our network(s)
                      for (multimap<uint256, CNode*>::iterator mi = mapMix.begin(); mi != mapMix.end() && nRelayNodes-- > 0; ++mi)
                          ((*mi).second)->PushAddress(addr);
                  }
              }
              // Do not store addresses outside our network
              if (fReachable)
                  vAddrOk.push_back(addr);
          }
          addrman.Add(vAddrOk, pfrom->addr, 2 * 60 * 60);
          if (vAddr.size() < 1000)
              pfrom->fGetAddr = false;
          if (pfrom->fOneShot)
              pfrom->fDisconnect = true;
      }
  
  
      else if (strCommand == "inv") {
          vector<CInv> vInv;
          vRecv >> vInv;
          if (vInv.size() > MAX_INV_SZ) {
              Misbehaving(pfrom->GetId(), 20);
              return error("message inv size() = %u", vInv.size());
          }
  
          LOCK(cs_main);
  
          std::vector<CInv> vToFetch;
  
          for (unsigned int nInv = 0; nInv < vInv.size(); nInv++) {
              const CInv& inv = vInv[nInv];
  
              boost::this_thread::interruption_point();
              pfrom->AddInventoryKnown(inv);
  
              bool fAlreadyHave = AlreadyHave(inv);
              LogPrint("net", "got inv: %s  %s peer=%d\n", inv.ToString(), fAlreadyHave ? "have" : "new", pfrom->id);
  
              if (!fAlreadyHave && !fImporting && !fReindex && inv.type != MSG_BLOCK)
                  pfrom->AskFor(inv);
  
  
              if (inv.type == MSG_BLOCK) {
                  UpdateBlockAvailability(pfrom->GetId(), inv.hash);
                  if (!fAlreadyHave && !fImporting && !fReindex && !mapBlocksInFlight.count(inv.hash)) {
                      // Add this to the list of blocks to request
                      vToFetch.push_back(inv);
                      LogPrint("net", "getblocks (%d) %s to peer=%d\n", pindexBestHeader->nHeight, inv.hash.ToString(), pfrom->id);
                  }
              }
  
              // Track requests for our stuff
              g_signals.Inventory(inv.hash);
  
              if (pfrom->nSendSize > (SendBufferSize() * 2)) {
                  Misbehaving(pfrom->GetId(), 50);
                  return error("send buffer size() = %u", pfrom->nSendSize);
              }
          }
  
          if (!vToFetch.empty())
              pfrom->PushMessage("getdata", vToFetch);
      }
  
  
      else if (strCommand == "getdata") {
          vector<CInv> vInv;
          vRecv >> vInv;
          if (vInv.size() > MAX_INV_SZ) {
              Misbehaving(pfrom->GetId(), 20);
              return error("message getdata size() = %u", vInv.size());
          }
  
          if (fDebug || (vInv.size() != 1))
              LogPrint("net", "received getdata (%u invsz) peer=%d\n", vInv.size(), pfrom->id);
  
          if ((fDebug && vInv.size() > 0) || (vInv.size() == 1))
              LogPrint("net", "received getdata for: %s peer=%d\n", vInv[0].ToString(), pfrom->id);
  
          pfrom->vRecvGetData.insert(pfrom->vRecvGetData.end(), vInv.begin(), vInv.end());
          ProcessGetData(pfrom);
      }
  
  
      else if (strCommand == "getblocks" || strCommand == "getheaders") {
          CBlockLocator locator;
          uint256 hashStop;
          vRecv >> locator >> hashStop;
  
          LOCK(cs_main);
  
          // Find the last block the caller has in the main chain
          CBlockIndex* pindex = FindForkInGlobalIndex(chainActive, locator);
  
          // Send the rest of the chain
          if (pindex)
              pindex = chainActive.Next(pindex);
          int nLimit = 500;
          LogPrintf("getblocks %d to %s limit %d from peer=%d\n", (pindex ? pindex->nHeight : -1), hashStop == uint256(0) ? "end" : hashStop.ToString(), nLimit, pfrom->id);
          for (; pindex; pindex = chainActive.Next(pindex)) {
              if (pindex->GetBlockHash() == hashStop) {
                  LogPrint("net", "  getblocks stopping at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                  break;
              }
              pfrom->PushInventory(CInv(MSG_BLOCK, pindex->GetBlockHash()));
              if (--nLimit <= 0) {
                  // When this block is requested, we'll send an inv that'll make them
                  // getblocks the next batch of inventory.
                  LogPrint("net", "  getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                  pfrom->hashContinue = pindex->GetBlockHash();
                  break;
              }
          }
      }
  
  
      else if (strCommand == "headers" && Params().HeadersFirstSyncingActive()) {
          CBlockLocator locator;
          uint256 hashStop;
          vRecv >> locator >> hashStop;
  
          LOCK(cs_main);
  
          if (IsInitialBlockDownload())
              return true;
  
          CBlockIndex* pindex = NULL;
          if (locator.IsNull()) {
              // If locator is null, return the hashStop block
              BlockMap::iterator mi = mapBlockIndex.find(hashStop);
              if (mi == mapBlockIndex.end())
                  return true;
              pindex = (*mi).second;
          } else {
              // Find the last block the caller has in the main chain
              pindex = FindForkInGlobalIndex(chainActive, locator);
              if (pindex)
                  pindex = chainActive.Next(pindex);
          }
  
          // we must use CBlocks, as CBlockHeaders won't include the 0x00 nTx count at the end
          vector<CBlock> vHeaders;
          int nLimit = MAX_HEADERS_RESULTS;
          if (fDebug)
              LogPrintf("getheaders %d to %s from peer=%d\n", (pindex ? pindex->nHeight : -1), hashStop.ToString(), pfrom->id);
          for (; pindex; pindex = chainActive.Next(pindex)) {
              vHeaders.push_back(pindex->GetBlockHeader());
              if (--nLimit <= 0 || pindex->GetBlockHash() == hashStop)
                  break;
          }
          pfrom->PushMessage("headers", vHeaders);
      }
  
  
      else if (strCommand == "tx" || strCommand == "dstx") {
          vector<uint256> vWorkQueue;
          vector<uint256> vEraseQueue;
          CTransaction tx;
  
          //masternode signed transaction
          bool ignoreFees = false;
          CTxIn vin;
          vector<unsigned char> vchSig;
          int64_t sigTime;
  
          if (strCommand == "tx") {
              vRecv >> tx;
          } else if (strCommand == "dstx") {
              //these allow masternodes to publish a limited amount of free transactions
              vRecv >> tx >> vin >> vchSig >> sigTime;
  
              CMasternode* pmn = mnodeman.Find(vin);
              if (pmn != NULL) {
                  if (!pmn->allowFreeTx) {
                      //multiple peers can send us a valid masternode transaction
                      if (fDebug) LogPrintf("dstx: Masternode sending too many transactions %s\n", tx.GetHash().ToString());
                      return true;
                  }
  
                  std::string strMessage = tx.GetHash().ToString() + boost::lexical_cast<std::string>(sigTime);
  
                  std::string errorMessage = "";
                  if (!obfuScationSigner.VerifyMessage(pmn->pubKeyMasternode, vchSig, strMessage, errorMessage)) {
                      LogPrintf("dstx: Got bad masternode address signature %s \n", vin.ToString());
                      //pfrom->Misbehaving(20);
                      return false;
                  }
  
                  LogPrintf("dstx: Got Masternode transaction %s\n", tx.GetHash().ToString());
  
                  ignoreFees = true;
                  pmn->allowFreeTx = false;
  
                  if (!mapObfuscationBroadcastTxes.count(tx.GetHash())) {
                      CObfuscationBroadcastTx dstx;
                      dstx.tx = tx;
                      dstx.vin = vin;
                      dstx.vchSig = vchSig;
                      dstx.sigTime = sigTime;
  
                      mapObfuscationBroadcastTxes.insert(make_pair(tx.GetHash(), dstx));
                  }
              }
          }
  
          CInv inv(MSG_TX, tx.GetHash());
          pfrom->AddInventoryKnown(inv);
  
          LOCK(cs_main);
  
          bool fMissingInputs = false;
          CValidationState state;
  
          mapAlreadyAskedFor.erase(inv);
  
          if (AcceptToMemoryPool(mempool, state, tx, true, &fMissingInputs, false, ignoreFees)) {
              mempool.check(pcoinsTip);
              RelayTransaction(tx);
              vWorkQueue.push_back(inv.hash);
  
              LogPrint("mempool", "AcceptToMemoryPool: peer=%d %s : accepted %s (poolsz %u)\n",
                  pfrom->id, pfrom->cleanSubVer,
                  tx.GetHash().ToString(),
                  mempool.mapTx.size());
  
              // Recursively process any orphan transactions that depended on this one
              set<NodeId> setMisbehaving;
              for (unsigned int i = 0; i < vWorkQueue.size(); i++) {
                  map<uint256, set<uint256> >::iterator itByPrev = mapOrphanTransactionsByPrev.find(vWorkQueue[i]);
                  if (itByPrev == mapOrphanTransactionsByPrev.end())
                      continue;
                  for (set<uint256>::iterator mi = itByPrev->second.begin();
                       mi != itByPrev->second.end();
                       ++mi) {
                      const uint256& orphanHash = *mi;
                      const CTransaction& orphanTx = mapOrphanTransactions[orphanHash].tx;
                      NodeId fromPeer = mapOrphanTransactions[orphanHash].fromPeer;
                      bool fMissingInputs2 = false;
                      // Use a dummy CValidationState so someone can't setup nodes to counter-DoS based on orphan
                      // resolution (that is, feeding people an invalid transaction based on LegitTxX in order to get
                      // anyone relaying LegitTxX banned)
                      CValidationState stateDummy;
  
  
                      if (setMisbehaving.count(fromPeer))
                          continue;
                      if (AcceptToMemoryPool(mempool, stateDummy, orphanTx, true, &fMissingInputs2)) {
                          LogPrint("mempool", "   accepted orphan tx %s\n", orphanHash.ToString());
                          RelayTransaction(orphanTx);
                          vWorkQueue.push_back(orphanHash);
                          vEraseQueue.push_back(orphanHash);
                      } else if (!fMissingInputs2) {
                          int nDos = 0;
                          if (stateDummy.IsInvalid(nDos) && nDos > 0) {
                              // Punish peer that gave us an invalid orphan tx
                              Misbehaving(fromPeer, nDos);
                              setMisbehaving.insert(fromPeer);
                              LogPrint("mempool", "   invalid orphan tx %s\n", orphanHash.ToString());
                          }
                          // Has inputs but not accepted to mempool
                          // Probably non-standard or insufficient fee/priority
                          LogPrint("mempool", "   removed orphan tx %s\n", orphanHash.ToString());
                          vEraseQueue.push_back(orphanHash);
                      }
                      mempool.check(pcoinsTip);
                  }
              }
  
              BOOST_FOREACH (uint256 hash, vEraseQueue)
                  EraseOrphanTx(hash);
          } else if (fMissingInputs) {
              AddOrphanTx(tx, pfrom->GetId());
  
              // DoS prevention: do not allow mapOrphanTransactions to grow unbounded
              unsigned int nMaxOrphanTx = (unsigned int)std::max((int64_t)0, GetArg("-maxorphantx", DEFAULT_MAX_ORPHAN_TRANSACTIONS));
              unsigned int nEvicted = LimitOrphanTxSize(nMaxOrphanTx);
              if (nEvicted > 0)
                  LogPrint("mempool", "mapOrphan overflow, removed %u tx\n", nEvicted);
          } else if (pfrom->fWhitelisted) {
              // Always relay transactions received from whitelisted peers, even
              // if they are already in the mempool (allowing the node to function
              // as a gateway for nodes hidden behind it).
  
              RelayTransaction(tx);
          }
  
          if (strCommand == "dstx") {
              CInv inv(MSG_DSTX, tx.GetHash());
              RelayInv(inv);
          }
  
          int nDoS = 0;
          if (state.IsInvalid(nDoS)) {
              LogPrint("mempool", "%s from peer=%d %s was not accepted into the memory pool: %s\n", tx.GetHash().ToString(),
                  pfrom->id, pfrom->cleanSubVer,
                  state.GetRejectReason());
              pfrom->PushMessage("reject", strCommand, state.GetRejectCode(),
                  state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), inv.hash);
              if (nDoS > 0)
                  Misbehaving(pfrom->GetId(), nDoS);
          }
      }
  
  
      else if (strCommand == "headers" && Params().HeadersFirstSyncingActive() && !fImporting && !fReindex) // Ignore headers received while importing
      {
          std::vector<CBlockHeader> headers;
  
          // Bypass the normal CBlock deserialization, as we don't want to risk deserializing 2000 full blocks.
          unsigned int nCount = ReadCompactSize(vRecv);
          if (nCount > MAX_HEADERS_RESULTS) {
              Misbehaving(pfrom->GetId(), 20);
              return error("headers message size = %u", nCount);
          }
          headers.resize(nCount);
          for (unsigned int n = 0; n < nCount; n++) {
              vRecv >> headers[n];
              ReadCompactSize(vRecv); // ignore tx count; assume it is 0.
          }
  
          LOCK(cs_main);
  
          if (nCount == 0) {
              // Nothing interesting. Stop asking this peers for more headers.
              return true;
          }
          CBlockIndex* pindexLast = NULL;
          BOOST_FOREACH (const CBlockHeader& header, headers) {
              CValidationState state;
              if (pindexLast != NULL && header.hashPrevBlock != pindexLast->GetBlockHash()) {
                  Misbehaving(pfrom->GetId(), 20);
                  return error("non-continuous headers sequence");
              }
  
              /*TODO: this has a CBlock cast on it so that it will compile. There should be a solution for this
               * before headers are reimplemented on mainnet
               */
              if (!AcceptBlockHeader((CBlock)header, state, &pindexLast)) {
                  int nDoS;
                  if (state.IsInvalid(nDoS)) {
                      if (nDoS > 0)
                          Misbehaving(pfrom->GetId(), nDoS);
                      std::string strError = "invalid header received " + header.GetHash().ToString();
                      return error(strError.c_str());
                  }
              }
          }
  
          if (pindexLast)
              UpdateBlockAvailability(pfrom->GetId(), pindexLast->GetBlockHash());
  
          if (nCount == MAX_HEADERS_RESULTS && pindexLast) {
              // Headers message had its maximum size; the peer may have more headers.
              // TODO: optimize: if pindexLast is an ancestor of chainActive.Tip or pindexBestHeader, continue
              // from there instead.
              LogPrintf("more getheaders (%d) to end to peer=%d (startheight:%d)\n", pindexLast->nHeight, pfrom->id, pfrom->nStartingHeight);
              pfrom->PushMessage("getheaders", chainActive.GetLocator(pindexLast), uint256(0));
          }
  
          CheckBlockIndex();
      }
  
      else if (strCommand == "block" && !fImporting && !fReindex) // Ignore blocks received while importing
      {
          CBlock block;
          vRecv >> block;
          uint256 hashBlock = block.GetHash();
          CInv inv(MSG_BLOCK, hashBlock);
          LogPrint("net", "received block %s peer=%d\n", inv.hash.ToString(), pfrom->id);
  
          //sometimes we will be sent their most recent block and its not the one we want, in that case tell where we are
          if (!mapBlockIndex.count(block.hashPrevBlock)) {
              if (find(pfrom->vBlockRequested.begin(), pfrom->vBlockRequested.end(), hashBlock) != pfrom->vBlockRequested.end()) {
                  //we already asked for this block, so lets work backwards and ask for the previous block
                  pfrom->PushMessage("getblocks", chainActive.GetLocator(), block.hashPrevBlock);
                  pfrom->vBlockRequested.push_back(block.hashPrevBlock);
              } else {
                  //ask to sync to this block
                  pfrom->PushMessage("getblocks", chainActive.GetLocator(), hashBlock);
                  pfrom->vBlockRequested.push_back(hashBlock);
              }
          } else {
              pfrom->AddInventoryKnown(inv);
  
              CValidationState state;
              ProcessNewBlock(state, pfrom, &block);
              int nDoS;
              if (state.IsInvalid(nDoS)) {
                  pfrom->PushMessage("reject", strCommand, state.GetRejectCode(),
                      state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), inv.hash);
                  if (nDoS > 0) {
                      TRY_LOCK(cs_main, lockMain);
                      if (lockMain) Misbehaving(pfrom->GetId(), nDoS);
                  }
              }
          }
  
      }
  
  
      // This asymmetric behavior for inbound and outbound connections was introduced
      // to prevent a fingerprinting attack: an attacker can send specific fake addresses
      // to users' AddrMan and later request them by sending getaddr messages.
      // Making users (which are behind NAT and can only make outgoing connections) ignore
      // getaddr message mitigates the attack.
      else if ((strCommand == "getaddr") && (pfrom->fInbound)) {
          pfrom->vAddrToSend.clear();
          vector<CAddress> vAddr = addrman.GetAddr();
          BOOST_FOREACH (const CAddress& addr, vAddr)
              pfrom->PushAddress(addr);
      }
  
  
      else if (strCommand == "mempool") {
          LOCK2(cs_main, pfrom->cs_filter);
  
          std::vector<uint256> vtxid;
          mempool.queryHashes(vtxid);
          vector<CInv> vInv;
          BOOST_FOREACH (uint256& hash, vtxid) {
              CInv inv(MSG_TX, hash);
              CTransaction tx;
              bool fInMemPool = mempool.lookup(hash, tx);
              if (!fInMemPool) continue; // another thread removed since queryHashes, maybe...
              if ((pfrom->pfilter && pfrom->pfilter->IsRelevantAndUpdate(tx)) ||
                  (!pfrom->pfilter))
                  vInv.push_back(inv);
              if (vInv.size() == MAX_INV_SZ) {
                  pfrom->PushMessage("inv", vInv);
                  vInv.clear();
              }
          }
          if (vInv.size() > 0)
              pfrom->PushMessage("inv", vInv);
      }
  
  
      else if (strCommand == "ping") {
          if (pfrom->nVersion > BIP0031_VERSION) {
              uint64_t nonce = 0;
              vRecv >> nonce;
              // Echo the message back with the nonce. This allows for two useful features:
              //
              // 1) A remote node can quickly check if the connection is operational
              // 2) Remote nodes can measure the latency of the network thread. If this node
              //    is overloaded it won't respond to pings quickly and the remote node can
              //    avoid sending us more work, like chain download requests.
              //
              // The nonce stops the remote getting confused between different pings: without
              // it, if the remote node sends a ping once per second and this node takes 5
              // seconds to respond to each, the 5th ping the remote sends would appear to
              // return very quickly.
              pfrom->PushMessage("pong", nonce);
          }
      }
  
  
      else if (strCommand == "pong") {
          int64_t pingUsecEnd = nTimeReceived;
          uint64_t nonce = 0;
          size_t nAvail = vRecv.in_avail();
          bool bPingFinished = false;
          std::string sProblem;
  
          if (nAvail >= sizeof(nonce)) {
              vRecv >> nonce;
  
              // Only process pong message if there is an outstanding ping (old ping without nonce should never pong)
              if (pfrom->nPingNonceSent != 0) {
                  if (nonce == pfrom->nPingNonceSent) {
                      // Matching pong received, this ping is no longer outstanding
                      bPingFinished = true;
                      int64_t pingUsecTime = pingUsecEnd - pfrom->nPingUsecStart;
                      if (pingUsecTime > 0) {
                          // Successful ping time measurement, replace previous
                          pfrom->nPingUsecTime = pingUsecTime;
                      } else {
                          // This should never happen
                          sProblem = "Timing mishap";
                      }
                  } else {
                      // Nonce mismatches are normal when pings are overlapping
                      sProblem = "Nonce mismatch";
                      if (nonce == 0) {
                          // This is most likely a bug in another implementation somewhere, cancel this ping
                          bPingFinished = true;
                          sProblem = "Nonce zero";
                      }
                  }
              } else {
                  sProblem = "Unsolicited pong without ping";
              }
          } else {
              // This is most likely a bug in another implementation somewhere, cancel this ping
              bPingFinished = true;
              sProblem = "Short payload";
          }
  
          if (!(sProblem.empty())) {
              LogPrint("net", "pong peer=%d %s: %s, %x expected, %x received, %u bytes\n",
                  pfrom->id,
                  pfrom->cleanSubVer,
                  sProblem,
                  pfrom->nPingNonceSent,
                  nonce,
                  nAvail);
          }
          if (bPingFinished) {
              pfrom->nPingNonceSent = 0;
          }
      }
  
  
      else if (fAlerts && strCommand == "alert") {
          CAlert alert;
          vRecv >> alert;
  
          uint256 alertHash = alert.GetHash();
          if (pfrom->setKnown.count(alertHash) == 0) {
              if (alert.ProcessAlert()) {
                  // Relay
                  pfrom->setKnown.insert(alertHash);
                  {
                      LOCK(cs_vNodes);
                      BOOST_FOREACH (CNode* pnode, vNodes)
                          alert.RelayTo(pnode);
                  }
              } else {
                  // Small DoS penalty so peers that send us lots of
                  // duplicate/expired/invalid-signature/whatever alerts
                  // eventually get banned.
                  // This isn't a Misbehaving(100) (immediate ban) because the
                  // peer might be an older or different implementation with
                  // a different signature key, etc.
                  Misbehaving(pfrom->GetId(), 10);
              }
          }
      }
  
      else if (!(nLocalServices & NODE_BLOOM) &&
               (strCommand == "filterload" ||
                   strCommand == "filteradd" ||
                   strCommand == "filterclear")) {
          LogPrintf("bloom message=%s\n", strCommand);
          Misbehaving(pfrom->GetId(), 100);
      }
  
      else if (strCommand == "filterload") {
          CBloomFilter filter;
          vRecv >> filter;
  
          if (!filter.IsWithinSizeConstraints())
              // There is no excuse for sending a too-large filter
              Misbehaving(pfrom->GetId(), 100);
          else {
              LOCK(pfrom->cs_filter);
              delete pfrom->pfilter;
              pfrom->pfilter = new CBloomFilter(filter);
              pfrom->pfilter->UpdateEmptyFull();
          }
          pfrom->fRelayTxes = true;
      }
  
  
      else if (strCommand == "filteradd") {
          vector<unsigned char> vData;
          vRecv >> vData;
  
          // Nodes must NEVER send a data item > 520 bytes (the max size for a script data object,
          // and thus, the maximum size any matched object can have) in a filteradd message
          if (vData.size() > MAX_SCRIPT_ELEMENT_SIZE) {
              Misbehaving(pfrom->GetId(), 100);
          } else {
              LOCK(pfrom->cs_filter);
              if (pfrom->pfilter)
                  pfrom->pfilter->insert(vData);
              else
                  Misbehaving(pfrom->GetId(), 100);
          }
      }
  
  
      else if (strCommand == "filterclear") {
          LOCK(pfrom->cs_filter);
          delete pfrom->pfilter;
          pfrom->pfilter = new CBloomFilter();
          pfrom->fRelayTxes = true;
      }
  
  
      else if (strCommand == "reject") {
          if (fDebug) {
              try {
                  string strMsg;
                  unsigned char ccode;
                  string strReason;
                  vRecv >> LIMITED_STRING(strMsg, CMessageHeader::COMMAND_SIZE) >> ccode >> LIMITED_STRING(strReason, MAX_REJECT_MESSAGE_LENGTH);
  
                  ostringstream ss;
                  ss << strMsg << " code " << itostr(ccode) << ": " << strReason;
  
                  if (strMsg == "block" || strMsg == "tx") {
                      uint256 hash;
                      vRecv >> hash;
                      ss << ": hash " << hash.ToString();
                  }
                  LogPrint("net", "Reject %s\n", SanitizeString(ss.str()));
              } catch (std::ios_base::failure& e) {
                  // Avoid feedback loops by preventing reject messages from triggering a new reject message.
                  LogPrint("net", "Unparseable reject message received\n");
              }
          }
      } else {
          //probably one the extensions
          obfuScationPool.ProcessMessageObfuscation(pfrom, strCommand, vRecv);
          mnodeman.ProcessMessage(pfrom, strCommand, vRecv);
          budget.ProcessMessage(pfrom, strCommand, vRecv);
          masternodePayments.ProcessMessageMasternodePayments(pfrom, strCommand, vRecv);
          ProcessMessageSwiftTX(pfrom, strCommand, vRecv);
          ProcessSpork(pfrom, strCommand, vRecv);
          masternodeSync.ProcessMessage(pfrom, strCommand, vRecv);
      }
  
  
      return true;
  }
  
  int ActiveProtocol()
  {
      if (IsSporkActive(SPORK_14_NEW_PROTOCOL_ENFORCEMENT)) {
          if (chainActive.Tip()->nHeight >= Params().ModifierUpgradeBlock())
              return MIN_PEER_PROTO_VERSION_AFTER_ENFORCEMENT;
      }
  
      return MIN_PEER_PROTO_VERSION_BEFORE_ENFORCEMENT;
  }
  
  // requires LOCK(cs_vRecvMsg)
  bool ProcessMessages(CNode* pfrom)
  {
      //if (fDebug)
      //    LogPrintf("ProcessMessages(%u messages)\n", pfrom->vRecvMsg.size());
  
      //
      // Message format
      //  (4) message start
      //  (12) command
      //  (4) size
      //  (4) checksum
      //  (x) data
      //
      bool fOk = true;
  
      if (!pfrom->vRecvGetData.empty())
          ProcessGetData(pfrom);
  
      // this maintains the order of responses
      if (!pfrom->vRecvGetData.empty()) return fOk;
  
      std::deque<CNetMessage>::iterator it = pfrom->vRecvMsg.begin();
      while (!pfrom->fDisconnect && it != pfrom->vRecvMsg.end()) {
          // Don't bother if send buffer is too full to respond anyway
          if (pfrom->nSendSize >= SendBufferSize())
              break;
  
          // get next message
          CNetMessage& msg = *it;
  
          //if (fDebug)
          //    LogPrintf("ProcessMessages(message %u msgsz, %u bytes, complete:%s)\n",
          //            msg.hdr.nMessageSize, msg.vRecv.size(),
          //            msg.complete() ? "Y" : "N");
  
          // end, if an incomplete message is found
          if (!msg.complete())
              break;
  
          // at this point, any failure means we can delete the current message
          it++;
  
          // Scan for message start
          if (memcmp(msg.hdr.pchMessageStart, Params().MessageStart(), MESSAGE_START_SIZE) != 0) {
              LogPrintf("PROCESSMESSAGE: INVALID MESSAGESTART %s peer=%d\n", SanitizeString(msg.hdr.GetCommand()), pfrom->id);
              fOk = false;
              break;
          }
  
          // Read header
          CMessageHeader& hdr = msg.hdr;
          if (!hdr.IsValid()) {
              LogPrintf("PROCESSMESSAGE: ERRORS IN HEADER %s peer=%d\n", SanitizeString(hdr.GetCommand()), pfrom->id);
              continue;
          }
          string strCommand = hdr.GetCommand();
  
          // Message size
          unsigned int nMessageSize = hdr.nMessageSize;
  
          // Checksum
          CDataStream& vRecv = msg.vRecv;
          uint256 hash = Hash(vRecv.begin(), vRecv.begin() + nMessageSize);
          unsigned int nChecksum = 0;
          memcpy(&nChecksum, &hash, sizeof(nChecksum));
          if (nChecksum != hdr.nChecksum) {
              LogPrintf("ProcessMessages(%s, %u bytes): CHECKSUM ERROR nChecksum=%08x hdr.nChecksum=%08x\n",
                  SanitizeString(strCommand), nMessageSize, nChecksum, hdr.nChecksum);
              continue;
          }
  
          // Process message
          bool fRet = false;
          try {
              fRet = ProcessMessage(pfrom, strCommand, vRecv, msg.nTime);
              boost::this_thread::interruption_point();
          } catch (std::ios_base::failure& e) {
              pfrom->PushMessage("reject", strCommand, REJECT_MALFORMED, string("error parsing message"));
              if (strstr(e.what(), "end of data")) {
                  // Allow exceptions from under-length message on vRecv
                  LogPrintf("ProcessMessages(%s, %u bytes): Exception '%s' caught, normally caused by a message being shorter than its stated length\n", SanitizeString(strCommand), nMessageSize, e.what());
              } else if (strstr(e.what(), "size too large")) {
                  // Allow exceptions from over-long size
                  LogPrintf("ProcessMessages(%s, %u bytes): Exception '%s' caught\n", SanitizeString(strCommand), nMessageSize, e.what());
              } else {
                  PrintExceptionContinue(&e, "ProcessMessages()");
              }
          } catch (boost::thread_interrupted) {
              throw;
          } catch (std::exception& e) {
              PrintExceptionContinue(&e, "ProcessMessages()");
          } catch (...) {
              PrintExceptionContinue(NULL, "ProcessMessages()");
          }
  
          if (!fRet)
              LogPrintf("ProcessMessage(%s, %u bytes) FAILED peer=%d\n", SanitizeString(strCommand), nMessageSize, pfrom->id);
  
          break;
      }
  
      // In case the connection got shut down, its receive buffer was wiped
      if (!pfrom->fDisconnect)
          pfrom->vRecvMsg.erase(pfrom->vRecvMsg.begin(), it);
  
      return fOk;
  }
  
  
  bool SendMessages(CNode* pto, bool fSendTrickle)
  {
      {
          // Don't send anything until we get their version message
          if (pto->nVersion == 0)
              return true;
  
          //
          // Message: ping
          //
          bool pingSend = false;
          if (pto->fPingQueued) {
              // RPC ping request by user
              pingSend = true;
          }
          if (pto->nPingNonceSent == 0 && pto->nPingUsecStart + PING_INTERVAL * 1000000 < GetTimeMicros()) {
              // Ping automatically sent as a latency probe & keepalive.
              pingSend = true;
          }
          if (pingSend) {
              uint64_t nonce = 0;
              while (nonce == 0) {
                  GetRandBytes((unsigned char*)&nonce, sizeof(nonce));
              }
              pto->fPingQueued = false;
              pto->nPingUsecStart = GetTimeMicros();
              if (pto->nVersion > BIP0031_VERSION) {
                  pto->nPingNonceSent = nonce;
                  pto->PushMessage("ping", nonce);
              } else {
                  // Peer is too old to support ping command with nonce, pong will never arrive.
                  pto->nPingNonceSent = 0;
                  pto->PushMessage("ping");
              }
          }
  
          TRY_LOCK(cs_main, lockMain); // Acquire cs_main for IsInitialBlockDownload() and CNodeState()
          if (!lockMain)
              return true;
  
          // Address refresh broadcast
          static int64_t nLastRebroadcast;
          if (!IsInitialBlockDownload() && (GetTime() - nLastRebroadcast > 24 * 60 * 60)) {
              LOCK(cs_vNodes);
              BOOST_FOREACH (CNode* pnode, vNodes) {
                  // Periodically clear setAddrKnown to allow refresh broadcasts
                  if (nLastRebroadcast)
                      pnode->setAddrKnown.clear();
  
                  // Rebroadcast our address
                  AdvertizeLocal(pnode);
              }
              if (!vNodes.empty())
                  nLastRebroadcast = GetTime();
          }
  
          //
          // Message: addr
          //
          if (fSendTrickle) {
              vector<CAddress> vAddr;
              vAddr.reserve(pto->vAddrToSend.size());
              BOOST_FOREACH (const CAddress& addr, pto->vAddrToSend) {
                  // returns true if wasn't already contained in the set
                  if (pto->setAddrKnown.insert(addr).second) {
                      vAddr.push_back(addr);
                      // receiver rejects addr messages larger than 1000
                      if (vAddr.size() >= 1000) {
                          pto->PushMessage("addr", vAddr);
                          vAddr.clear();
                      }
                  }
              }
              pto->vAddrToSend.clear();
              if (!vAddr.empty())
                  pto->PushMessage("addr", vAddr);
          }
  
          CNodeState& state = *State(pto->GetId());
          if (state.fShouldBan) {
              if (pto->fWhitelisted)
                  LogPrintf("Warning: not punishing whitelisted peer %s!\n", pto->addr.ToString());
              else {
                  pto->fDisconnect = true;
                  if (pto->addr.IsLocal())
                      LogPrintf("Warning: not banning local peer %s!\n", pto->addr.ToString());
                  else {
                      CNode::Ban(pto->addr);
                  }
              }
              state.fShouldBan = false;
          }
  
          BOOST_FOREACH (const CBlockReject& reject, state.rejects)
              pto->PushMessage("reject", (string) "block", reject.chRejectCode, reject.strRejectReason, reject.hashBlock);
          state.rejects.clear();
  
          // Start block sync
          if (pindexBestHeader == NULL)
              pindexBestHeader = chainActive.Tip();
          bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->fOneShot); // Download if this is a nice peer, or we have no nice peers and this one might do.
          if (!state.fSyncStarted && !pto->fClient && fFetch /*&& !fImporting*/ && !fReindex) {
              // Only actively request headers from a single peer, unless we're close to end of initial download.
              if (nSyncStarted == 0 || pindexBestHeader->GetBlockTime() > GetAdjustedTime() - 6 * 60 * 60) { // NOTE: was "close to today" and 24h in Bitcoin
                  state.fSyncStarted = true;
                  nSyncStarted++;
                  //CBlockIndex *pindexStart = pindexBestHeader->pprev ? pindexBestHeader->pprev : pindexBestHeader;
                  //LogPrint("net", "initial getheaders (%d) to peer=%d (startheight:%d)\n", pindexStart->nHeight, pto->id, pto->nStartingHeight);
                  //pto->PushMessage("getheaders", chainActive.GetLocator(pindexStart), uint256(0));
                  pto->PushMessage("getblocks", chainActive.GetLocator(chainActive.Tip()), uint256(0));
              }
          }
  
          // Resend wallet transactions that haven't gotten in a block yet
          // Except during reindex, importing and IBD, when old wallet
          // transactions become unconfirmed and spams other nodes.
          if (!fReindex /*&& !fImporting && !IsInitialBlockDownload()*/) {
              g_signals.Broadcast();
          }
  
          //
          // Message: inventory
          //
          vector<CInv> vInv;
          vector<CInv> vInvWait;
          {
              LOCK(pto->cs_inventory);
              vInv.reserve(pto->vInventoryToSend.size());
              vInvWait.reserve(pto->vInventoryToSend.size());
              BOOST_FOREACH (const CInv& inv, pto->vInventoryToSend) {
                  if (pto->setInventoryKnown.count(inv))
                      continue;
  
                  // trickle out tx inv to protect privacy
                  if (inv.type == MSG_TX && !fSendTrickle) {
                      // 1/4 of tx invs blast to all immediately
                      static uint256 hashSalt;
                      if (hashSalt == 0)
                          hashSalt = GetRandHash();
                      uint256 hashRand = inv.hash ^ hashSalt;
                      hashRand = Hash(BEGIN(hashRand), END(hashRand));
                      bool fTrickleWait = ((hashRand & 3) != 0);
  
                      if (fTrickleWait) {
                          vInvWait.push_back(inv);
                          continue;
                      }
                  }
  
                  // returns true if wasn't already contained in the set
                  if (pto->setInventoryKnown.insert(inv).second) {
                      vInv.push_back(inv);
                      if (vInv.size() >= 1000) {
                          pto->PushMessage("inv", vInv);
                          vInv.clear();
                      }
                  }
              }
              pto->vInventoryToSend = vInvWait;
          }
          if (!vInv.empty())
              pto->PushMessage("inv", vInv);
  
          // Detect whether we're stalling
          int64_t nNow = GetTimeMicros();
          if (!pto->fDisconnect && state.nStallingSince && state.nStallingSince < nNow - 1000000 * BLOCK_STALLING_TIMEOUT) {
              // Stalling only triggers when the block download window cannot move. During normal steady state,
              // the download window should be much larger than the to-be-downloaded set of blocks, so disconnection
              // should only happen during initial block download.
              LogPrintf("Peer=%d is stalling block download, disconnecting\n", pto->id);
              pto->fDisconnect = true;
          }
          // In case there is a block that has been in flight from this peer for (2 + 0.5 * N) times the block interval
          // (with N the number of validated blocks that were in flight at the time it was requested), disconnect due to
          // timeout. We compensate for in-flight blocks to prevent killing off peers due to our own downstream link
          // being saturated. We only count validated in-flight blocks so peers can't advertize nonexisting block hashes
          // to unreasonably increase our timeout.
          if (!pto->fDisconnect && state.vBlocksInFlight.size() > 0 && state.vBlocksInFlight.front().nTime < nNow - 500000 * Params().TargetSpacing() * (4 + state.vBlocksInFlight.front().nValidatedQueuedBefore)) {
              LogPrintf("Timeout downloading block %s from peer=%d, disconnecting\n", state.vBlocksInFlight.front().hash.ToString(), pto->id);
              pto->fDisconnect = true;
          }
  
          //
          // Message: getdata (blocks)
          //
          vector<CInv> vGetData;
          if (!pto->fDisconnect && !pto->fClient && fFetch && state.nBlocksInFlight < MAX_BLOCKS_IN_TRANSIT_PER_PEER) {
              vector<CBlockIndex*> vToDownload;
              NodeId staller = -1;
              FindNextBlocksToDownload(pto->GetId(), MAX_BLOCKS_IN_TRANSIT_PER_PEER - state.nBlocksInFlight, vToDownload, staller);
              BOOST_FOREACH (CBlockIndex* pindex, vToDownload) {
                  vGetData.push_back(CInv(MSG_BLOCK, pindex->GetBlockHash()));
                  MarkBlockAsInFlight(pto->GetId(), pindex->GetBlockHash(), pindex);
                  LogPrintf("Requesting block %s (%d) peer=%d\n", pindex->GetBlockHash().ToString(),
                      pindex->nHeight, pto->id);
              }
              if (state.nBlocksInFlight == 0 && staller != -1) {
                  if (State(staller)->nStallingSince == 0) {
                      State(staller)->nStallingSince = nNow;
                      LogPrint("net", "Stall started peer=%d\n", staller);
                  }
              }
          }
  
          //
          // Message: getdata (non-blocks)
          //
          while (!pto->fDisconnect && !pto->mapAskFor.empty() && (*pto->mapAskFor.begin()).first <= nNow) {
              const CInv& inv = (*pto->mapAskFor.begin()).second;
              if (!AlreadyHave(inv)) {
                  if (fDebug)
                      LogPrint("net", "Requesting %s peer=%d\n", inv.ToString(), pto->id);
                  vGetData.push_back(inv);
                  if (vGetData.size() >= 1000) {
                      pto->PushMessage("getdata", vGetData);
                      vGetData.clear();
                  }
              }
              pto->mapAskFor.erase(pto->mapAskFor.begin());
          }
          if (!vGetData.empty())
              pto->PushMessage("getdata", vGetData);
      }
      return true;
  }
  
  
  bool CBlockUndo::WriteToDisk(CDiskBlockPos& pos, const uint256& hashBlock)
  {
      // Open history file to append
      CAutoFile fileout(OpenUndoFile(pos), SER_DISK, CLIENT_VERSION);
      if (fileout.IsNull())
          return error("CBlockUndo::WriteToDisk : OpenUndoFile failed");
  
      // Write index header
      unsigned int nSize = fileout.GetSerializeSize(*this);
      fileout << FLATDATA(Params().MessageStart()) << nSize;
  
      // Write undo data
      long fileOutPos = ftell(fileout.Get());
      if (fileOutPos < 0)
          return error("CBlockUndo::WriteToDisk : ftell failed");
      pos.nPos = (unsigned int)fileOutPos;
      fileout << *this;
  
      // calculate & write checksum
      CHashWriter hasher(SER_GETHASH, PROTOCOL_VERSION);
      hasher << hashBlock;
      hasher << *this;
      fileout << hasher.GetHash();
  
      return true;
  }
  
  bool CBlockUndo::ReadFromDisk(const CDiskBlockPos& pos, const uint256& hashBlock)
  {
      // Open history file to read
      CAutoFile filein(OpenUndoFile(pos, true), SER_DISK, CLIENT_VERSION);
      if (filein.IsNull())
          return error("CBlockUndo::ReadFromDisk : OpenBlockFile failed");
  
      // Read block
      uint256 hashChecksum;
      try {
          filein >> *this;
          filein >> hashChecksum;
      } catch (std::exception& e) {
          return error("%s : Deserialize or I/O error - %s", __func__, e.what());
      }
  
      // Verify checksum
      CHashWriter hasher(SER_GETHASH, PROTOCOL_VERSION);
      hasher << hashBlock;
      hasher << *this;
      if (hashChecksum != hasher.GetHash())
          return error("CBlockUndo::ReadFromDisk : Checksum mismatch");
  
      return true;
  }
  
  std::string CBlockFileInfo::ToString() const
  {
      return strprintf("CBlockFileInfo(blocks=%u, size=%u, heights=%u...%u, time=%s...%s)", nBlocks, nSize, nHeightFirst, nHeightLast, DateTimeStrFormat("%Y-%m-%d", nTimeFirst), DateTimeStrFormat("%Y-%m-%d", nTimeLast));
  }
  
  
  class CMainCleanup
  {
  public:
      CMainCleanup() {}
      ~CMainCleanup()
      {
          // block headers
          BlockMap::iterator it1 = mapBlockIndex.begin();
          for (; it1 != mapBlockIndex.end(); it1++)
              delete (*it1).second;
          mapBlockIndex.clear();
  
          // orphan transactions
          mapOrphanTransactions.clear();
          mapOrphanTransactionsByPrev.clear();
      }
  } instance_of_cmaincleanup;
  