text: // Copyright (c) 2012 Pieter Wuille
  // Copyright (c) 2012-2020 The Bitcoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef RUVCHAIN_ADDRMAN_H
  #define RUVCHAIN_ADDRMAN_H
  
  #include <clientversion.h>
  #include <config/ruvchain-config.h>
  #include <netaddress.h>
  #include <protocol.h>
  #include <random.h>
  #include <sync.h>
  #include <timedata.h>
  #include <tinyformat.h>
  #include <util/system.h>
  
  #include <fs.h>
  #include <hash.h>
  #include <iostream>
  #include <map>
  #include <set>
  #include <stdint.h>
  #include <streams.h>
  #include <vector>
  
  /**
   * Extended statistics about a CAddress
   */
  class CAddrInfo : public CAddress
  {
  public:
      //! last try whatsoever by us (memory only)
      int64_t nLastTry{0};
  
      //! last counted attempt (memory only)
      int64_t nLastCountAttempt{0};
  
  private:
      //! where knowledge about this address first came from
      CNetAddr source;
  
      //! last successful connection by us
      int64_t nLastSuccess{0};
  
      //! connection attempts since last successful attempt
      int nAttempts{0};
  
      //! reference count in new sets (memory only)
      int nRefCount{0};
  
      //! in tried set? (memory only)
      bool fInTried{false};
  
      //! position in vRandom
      int nRandomPos{-1};
  
      friend class CAddrMan;
  
  public:
  
      SERIALIZE_METHODS(CAddrInfo, obj)
      {
          READWRITEAS(CAddress, obj);
          READWRITE(obj.source, obj.nLastSuccess, obj.nAttempts);
      }
  
      CAddrInfo(const CAddress &addrIn, const CNetAddr &addrSource) : CAddress(addrIn), source(addrSource)
      {
      }
  
      CAddrInfo() : CAddress(), source()
      {
      }
  
      //! Calculate in which "tried" bucket this entry belongs
      int GetTriedBucket(const uint256 &nKey, const std::vector<bool> &asmap) const;
  
      //! Calculate in which "new" bucket this entry belongs, given a certain source
      int GetNewBucket(const uint256 &nKey, const CNetAddr& src, const std::vector<bool> &asmap) const;
  
      //! Calculate in which "new" bucket this entry belongs, using its default source
      int GetNewBucket(const uint256 &nKey, const std::vector<bool> &asmap) const
      {
          return GetNewBucket(nKey, source, asmap);
      }
  
      //! Calculate in which position of a bucket to store this entry.
      int GetBucketPosition(const uint256 &nKey, bool fNew, int nBucket) const;
  
      //! Determine whether the statistics about this entry are bad enough so that it can just be deleted
      bool IsTerrible(int64_t nNow = GetAdjustedTime()) const;
  
      //! Calculate the relative chance this entry should be given when selecting nodes to connect to
      double GetChance(int64_t nNow = GetAdjustedTime()) const;
  };
  
  /** Stochastic address manager
   *
   * Design goals:
   *  * Keep the address tables in-memory, and asynchronously dump the entire table to peers.dat.
   *  * Make sure no (localized) attacker can fill the entire table with his nodes/addresses.
   *
   * To that end:
   *  * Addresses are organized into buckets.
   *    * Addresses that have not yet been tried go into 1024 "new" buckets.
   *      * Based on the address range (/16 for IPv4) of the source of information, 64 buckets are selected at random.
   *      * The actual bucket is chosen from one of these, based on the range in which the address itself is located.
   *      * One single address can occur in up to 8 different buckets to increase selection chances for addresses that
   *        are seen frequently. The chance for increasing this multiplicity decreases exponentially.
   *      * When adding a new address to a full bucket, a randomly chosen entry (with a bias favoring less recently seen
   *        ones) is removed from it first.
   *    * Addresses of nodes that are known to be accessible go into 256 "tried" buckets.
   *      * Each address range selects at random 8 of these buckets.
   *      * The actual bucket is chosen from one of these, based on the full address.
   *      * When adding a new good address to a full bucket, a randomly chosen entry (with a bias favoring less recently
   *        tried ones) is evicted from it, back to the "new" buckets.
   *    * Bucket selection is based on cryptographic hashing, using a randomly-generated 256-bit key, which should not
   *      be observable by adversaries.
   *    * Several indexes are kept for high performance. Defining DEBUG_ADDRMAN will introduce frequent (and expensive)
   *      consistency checks for the entire data structure.
   */
  
  //! total number of buckets for tried addresses
  #define ADDRMAN_TRIED_BUCKET_COUNT_LOG2 8
  
  //! total number of buckets for new addresses
  #define ADDRMAN_NEW_BUCKET_COUNT_LOG2 10
  
  //! maximum allowed number of entries in buckets for new and tried addresses
  #define ADDRMAN_BUCKET_SIZE_LOG2 6
  
  //! over how many buckets entries with tried addresses from a single group (/16 for IPv4) are spread
  #define ADDRMAN_TRIED_BUCKETS_PER_GROUP 8
  
  //! over how many buckets entries with new addresses originating from a single group are spread
  #define ADDRMAN_NEW_BUCKETS_PER_SOURCE_GROUP 64
  
  //! in how many buckets for entries with new addresses a single address may occur
  #define ADDRMAN_NEW_BUCKETS_PER_ADDRESS 8
  
  //! how old addresses can maximally be
  #define ADDRMAN_HORIZON_DAYS 30
  
  //! after how many failed attempts we give up on a new node
  #define ADDRMAN_RETRIES 3
  
  //! how many successive failures are allowed ...
  #define ADDRMAN_MAX_FAILURES 10
  
  //! ... in at least this many days
  #define ADDRMAN_MIN_FAIL_DAYS 7
  
  //! how recent a successful connection should be before we allow an address to be evicted from tried
  #define ADDRMAN_REPLACEMENT_HOURS 4
  
  //! Convenience
  #define ADDRMAN_TRIED_BUCKET_COUNT (1 << ADDRMAN_TRIED_BUCKET_COUNT_LOG2)
  #define ADDRMAN_NEW_BUCKET_COUNT (1 << ADDRMAN_NEW_BUCKET_COUNT_LOG2)
  #define ADDRMAN_BUCKET_SIZE (1 << ADDRMAN_BUCKET_SIZE_LOG2)
  
  //! the maximum number of tried addr collisions to store
  #define ADDRMAN_SET_TRIED_COLLISION_SIZE 10
  
  //! the maximum time we'll spend trying to resolve a tried table collision, in seconds
  static const int64_t ADDRMAN_TEST_WINDOW = 40*60; // 40 minutes
  
  /**
   * Stochastical (IP) address manager
   */
  class CAddrMan
  {
  friend class CAddrManTest;
  protected:
      //! critical section to protect the inner data structures
      mutable RecursiveMutex cs;
  
  private:
      //! Serialization versions.
      enum Format : uint8_t {
          V0_HISTORICAL = 0,    //!< historic format, before commit e6b343d88
          V1_DETERMINISTIC = 1, //!< for pre-asmap files
          V2_ASMAP = 2,         //!< for files including asmap version
          V3_BIP155 = 3,        //!< same as V2_ASMAP plus addresses are in BIP155 format
      };
  
      //! The maximum format this software knows it can unserialize. Also, we always serialize
      //! in this format.
      //! The format (first byte in the serialized stream) can be higher than this and
      //! still this software may be able to unserialize the file - if the second byte
      //! (see `lowest_compatible` in `Unserialize()`) is less or equal to this.
      static constexpr Format FILE_FORMAT = Format::V3_BIP155;
  
      //! The initial value of a field that is incremented every time an incompatible format
      //! change is made (such that old software versions would not be able to parse and
      //! understand the new file format). This is 32 because we overtook the "key size"
      //! field which was 32 historically.
      //! @note Don't increment this. Increment `lowest_compatible` in `Serialize()` instead.
      static constexpr uint8_t INCOMPATIBILITY_BASE = 32;
  
      //! last used nId
      int nIdCount GUARDED_BY(cs);
  
      //! table with information about all nIds
      std::map<int, CAddrInfo> mapInfo GUARDED_BY(cs);
  
      //! find an nId based on its network address
      std::map<CNetAddr, int> mapAddr GUARDED_BY(cs);
  
      //! randomly-ordered vector of all nIds
      std::vector<int> vRandom GUARDED_BY(cs);
  
      // number of "tried" entries
      int nTried GUARDED_BY(cs);
  
      //! list of "tried" buckets
      int vvTried[ADDRMAN_TRIED_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE] GUARDED_BY(cs);
  
      //! number of (unique) "new" entries
      int nNew GUARDED_BY(cs);
  
      //! list of "new" buckets
      int vvNew[ADDRMAN_NEW_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE] GUARDED_BY(cs);
  
      //! last time Good was called (memory only)
      int64_t nLastGood GUARDED_BY(cs);
  
      //! Holds addrs inserted into tried table that collide with existing entries. Test-before-evict discipline used to resolve these collisions.
      std::set<int> m_tried_collisions;
  
  protected:
      //! secret key to randomize bucket select with
      uint256 nKey;
  
      //! Source of random numbers for randomization in inner loops
      FastRandomContext insecure_rand;
  
      //! Find an entry.
      CAddrInfo* Find(const CNetAddr& addr, int *pnId = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! find an entry, creating it if necessary.
      //! nTime and nServices of the found node are updated, if necessary.
      CAddrInfo* Create(const CAddress &addr, const CNetAddr &addrSource, int *pnId = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Swap two elements in vRandom.
      void SwapRandom(unsigned int nRandomPos1, unsigned int nRandomPos2) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Move an entry from the "new" table(s) to the "tried" table
      void MakeTried(CAddrInfo& info, int nId) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Delete an entry. It must not be in tried, and have refcount 0.
      void Delete(int nId) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Clear a position in a "new" table. This is the only place where entries are actually deleted.
      void ClearNew(int nUBucket, int nUBucketPos) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Mark an entry "good", possibly moving it from "new" to "tried".
      void Good_(const CService &addr, bool test_before_evict, int64_t time) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Add an entry to the "new" table.
      bool Add_(const CAddress &addr, const CNetAddr& source, int64_t nTimePenalty) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Mark an entry as attempted to connect.
      void Attempt_(const CService &addr, bool fCountFailure, int64_t nTime) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Select an address to connect to, if newOnly is set to true, only the new table is selected from.
      CAddrInfo Select_(bool newOnly) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! See if any to-be-evicted tried table entries have been tested and if so resolve the collisions.
      void ResolveCollisions_() EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Return a random to-be-evicted tried table address.
      CAddrInfo SelectTriedCollision_() EXCLUSIVE_LOCKS_REQUIRED(cs);
  
  #ifdef DEBUG_ADDRMAN
      //! Perform consistency check. Returns an error code or zero.
      int Check_() EXCLUSIVE_LOCKS_REQUIRED(cs);
  #endif
  
      //! Select several addresses at once.
      void GetAddr_(std::vector<CAddress> &vAddr, size_t max_addresses, size_t max_pct) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Mark an entry as currently-connected-to.
      void Connected_(const CService &addr, int64_t nTime) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
      //! Update an entry's service bits.
      void SetServices_(const CService &addr, ServiceFlags nServices) EXCLUSIVE_LOCKS_REQUIRED(cs);
  
  public:
      // Compressed IP->ASN mapping, loaded from a file when a node starts.
      // Should be always empty if no file was provided.
      // This mapping is then used for bucketing nodes in Addrman.
      //
      // If asmap is provided, nodes will be bucketed by
      // AS they belong to, in order to make impossible for a node
      // to connect to several nodes hosted in a single AS.
      // This is done in response to Erebus attack, but also to generally
      // diversify the connections every node creates,
      // especially useful when a large fraction of nodes
      // operate under a couple of cloud providers.
      //
      // If a new asmap was provided, the existing records
      // would be re-bucketed accordingly.
      std::vector<bool> m_asmap;
  
      // Read asmap from provided binary file
      static std::vector<bool> DecodeAsmap(fs::path path);
  
  
      /**
       * Serialized format.
       * * format version byte (@see `Format`)
       * * lowest compatible format version byte. This is used to help old software decide
       *   whether to parse the file. For example:
       *   * Ruvchain Core version N knows how to parse up to format=3. If a new format=4 is
       *     introduced in version N+1 that is compatible with format=3 and it is known that
       *     version N will be able to parse it, then version N+1 will write
       *     (format=4, lowest_compatible=3) in the first two bytes of the file, and so
       *     version N will still try to parse it.
       *   * Ruvchain Core version N+2 introduces a new incompatible format=5. It will write
       *     (format=5, lowest_compatible=5) and so any versions that do not know how to parse
       *     format=5 will not try to read the file.
       * * nKey
       * * nNew
       * * nTried
       * * number of "new" buckets XOR 2**30
       * * all nNew addrinfos in vvNew
       * * all nTried addrinfos in vvTried
       * * for each bucket:
       *   * number of elements
       *   * for each element: index
       *
       * 2**30 is xorred with the number of buckets to make addrman deserializer v0 detect it
       * as incompatible. This is necessary because it did not check the version number on
       * deserialization.
       *
       * Notice that vvTried, mapAddr and vVector are never encoded explicitly;
       * they are instead reconstructed from the other information.
       *
       * vvNew is serialized, but only used if ADDRMAN_UNKNOWN_BUCKET_COUNT didn't change,
       * otherwise it is reconstructed as well.
       *
       * This format is more complex, but significantly smaller (at most 1.5 MiB), and supports
       * changes to the ADDRMAN_ parameters without breaking the on-disk structure.
       *
       * We don't use SERIALIZE_METHODS since the serialization and deserialization code has
       * very little in common.
       */
      template <typename Stream>
      void Serialize(Stream& s_) const
      {
          LOCK(cs);
  
          // Always serialize in the latest version (FILE_FORMAT).
  
          OverrideStream<Stream> s(&s_, s_.GetType(), s_.GetVersion() | ADDRV2_FORMAT);
  
          s << static_cast<uint8_t>(FILE_FORMAT);
  
          // Increment `lowest_compatible` iff a newly introduced format is incompatible with
          // the previous one.
          static constexpr uint8_t lowest_compatible = Format::V3_BIP155;
          s << static_cast<uint8_t>(INCOMPATIBILITY_BASE + lowest_compatible);
  
          s << nKey;
          s << nNew;
          s << nTried;
  
          int nUBuckets = ADDRMAN_NEW_BUCKET_COUNT ^ (1 << 30);
          s << nUBuckets;
          std::map<int, int> mapUnkIds;
          int nIds = 0;
          for (const auto& entry : mapInfo) {
              mapUnkIds[entry.first] = nIds;
              const CAddrInfo &info = entry.second;
              if (info.nRefCount) {
                  assert(nIds != nNew); // this means nNew was wrong, oh ow
                  s << info;
                  nIds++;
              }
          }
          nIds = 0;
          for (const auto& entry : mapInfo) {
              const CAddrInfo &info = entry.second;
              if (info.fInTried) {
                  assert(nIds != nTried); // this means nTried was wrong, oh ow
                  s << info;
                  nIds++;
              }
          }
          for (int bucket = 0; bucket < ADDRMAN_NEW_BUCKET_COUNT; bucket++) {
              int nSize = 0;
              for (int i = 0; i < ADDRMAN_BUCKET_SIZE; i++) {
                  if (vvNew[bucket][i] != -1)
                      nSize++;
              }
              s << nSize;
              for (int i = 0; i < ADDRMAN_BUCKET_SIZE; i++) {
                  if (vvNew[bucket][i] != -1) {
                      int nIndex = mapUnkIds[vvNew[bucket][i]];
                      s << nIndex;
                  }
              }
          }
          // Store asmap version after bucket entries so that it
          // can be ignored by older clients for backward compatibility.
          uint256 asmap_version;
          if (m_asmap.size() != 0) {
              asmap_version = SerializeHash(m_asmap);
          }
          s << asmap_version;
      }
  
      template <typename Stream>
      void Unserialize(Stream& s_)
      {
          LOCK(cs);
  
          Clear();
  
          Format format;
          s_ >> Using<CustomUintFormatter<1>>(format);
  
          int stream_version = s_.GetVersion();
          if (format >= Format::V3_BIP155) {
              // Add ADDRV2_FORMAT to the version so that the CNetAddr and CAddress
              // unserialize methods know that an address in addrv2 format is coming.
              stream_version |= ADDRV2_FORMAT;
          }
  
          OverrideStream<Stream> s(&s_, s_.GetType(), stream_version);
  
          uint8_t compat;
          s >> compat;
          const uint8_t lowest_compatible = compat - INCOMPATIBILITY_BASE;
          if (lowest_compatible > FILE_FORMAT) {
              throw std::ios_base::failure(strprintf(
                  "Unsupported format of addrman database: %u. It is compatible with formats >=%u, "
                  "but the maximum supported by this version of %s is %u.",
                  format, lowest_compatible, PACKAGE_NAME, static_cast<uint8_t>(FILE_FORMAT)));
          }
  
          s >> nKey;
          s >> nNew;
          s >> nTried;
          int nUBuckets = 0;
          s >> nUBuckets;
          if (format >= Format::V1_DETERMINISTIC) {
              nUBuckets ^= (1 << 30);
          }
  
          if (nNew > ADDRMAN_NEW_BUCKET_COUNT * ADDRMAN_BUCKET_SIZE) {
              throw std::ios_base::failure("Corrupt CAddrMan serialization, nNew exceeds limit.");
          }
  
          if (nTried > ADDRMAN_TRIED_BUCKET_COUNT * ADDRMAN_BUCKET_SIZE) {
              throw std::ios_base::failure("Corrupt CAddrMan serialization, nTried exceeds limit.");
          }
  
          // Deserialize entries from the new table.
          for (int n = 0; n < nNew; n++) {
              CAddrInfo &info = mapInfo[n];
              s >> info;
              mapAddr[info] = n;
              info.nRandomPos = vRandom.size();
              vRandom.push_back(n);
          }
          nIdCount = nNew;
  
          // Deserialize entries from the tried table.
          int nLost = 0;
          for (int n = 0; n < nTried; n++) {
              CAddrInfo info;
              s >> info;
              int nKBucket = info.GetTriedBucket(nKey, m_asmap);
              int nKBucketPos = info.GetBucketPosition(nKey, false, nKBucket);
              if (vvTried[nKBucket][nKBucketPos] == -1) {
                  info.nRandomPos = vRandom.size();
                  info.fInTried = true;
                  vRandom.push_back(nIdCount);
                  mapInfo[nIdCount] = info;
                  mapAddr[info] = nIdCount;
                  vvTried[nKBucket][nKBucketPos] = nIdCount;
                  nIdCount++;
              } else {
                  nLost++;
              }
          }
          nTried -= nLost;
  
          // Store positions in the new table buckets to apply later (if possible).
          std::map<int, int> entryToBucket; // Represents which entry belonged to which bucket when serializing
  
          for (int bucket = 0; bucket < nUBuckets; bucket++) {
              int nSize = 0;
              s >> nSize;
              for (int n = 0; n < nSize; n++) {
                  int nIndex = 0;
                  s >> nIndex;
                  if (nIndex >= 0 && nIndex < nNew) {
                      entryToBucket[nIndex] = bucket;
                  }
              }
          }
  
          uint256 supplied_asmap_version;
          if (m_asmap.size() != 0) {
              supplied_asmap_version = SerializeHash(m_asmap);
          }
          uint256 serialized_asmap_version;
          if (format >= Format::V2_ASMAP) {
              s >> serialized_asmap_version;
          }
  
          for (int n = 0; n < nNew; n++) {
              CAddrInfo &info = mapInfo[n];
              int bucket = entryToBucket[n];
              int nUBucketPos = info.GetBucketPosition(nKey, true, bucket);
              if (format >= Format::V2_ASMAP && nUBuckets == ADDRMAN_NEW_BUCKET_COUNT && vvNew[bucket][nUBucketPos] == -1 &&
                  info.nRefCount < ADDRMAN_NEW_BUCKETS_PER_ADDRESS && serialized_asmap_version == supplied_asmap_version) {
                  // Bucketing has not changed, using existing bucket positions for the new table
                  vvNew[bucket][nUBucketPos] = n;
                  info.nRefCount++;
              } else {
                  // In case the new table data cannot be used (format unknown, bucket count wrong or new asmap),
                  // try to give them a reference based on their primary source address.
                  LogPrint(BCLog::ADDRMAN, "Bucketing method was updated, re-bucketing addrman entries from disk\n");
                  bucket = info.GetNewBucket(nKey, m_asmap);
                  nUBucketPos = info.GetBucketPosition(nKey, true, bucket);
                  if (vvNew[bucket][nUBucketPos] == -1) {
                      vvNew[bucket][nUBucketPos] = n;
                      info.nRefCount++;
                  }
              }
          }
  
          // Prune new entries with refcount 0 (as a result of collisions).
          int nLostUnk = 0;
          for (std::map<int, CAddrInfo>::const_iterator it = mapInfo.begin(); it != mapInfo.end(); ) {
              if (it->second.fInTried == false && it->second.nRefCount == 0) {
                  std::map<int, CAddrInfo>::const_iterator itCopy = it++;
                  Delete(itCopy->first);
                  nLostUnk++;
              } else {
                  it++;
              }
          }
          if (nLost + nLostUnk > 0) {
              LogPrint(BCLog::ADDRMAN, "addrman lost %i new and %i tried addresses due to collisions\n", nLostUnk, nLost);
          }
  
          Check();
      }
  
      void Clear()
      {
          LOCK(cs);
          std::vector<int>().swap(vRandom);
          nKey = insecure_rand.rand256();
          for (size_t bucket = 0; bucket < ADDRMAN_NEW_BUCKET_COUNT; bucket++) {
              for (size_t entry = 0; entry < ADDRMAN_BUCKET_SIZE; entry++) {
                  vvNew[bucket][entry] = -1;
              }
          }
          for (size_t bucket = 0; bucket < ADDRMAN_TRIED_BUCKET_COUNT; bucket++) {
              for (size_t entry = 0; entry < ADDRMAN_BUCKET_SIZE; entry++) {
                  vvTried[bucket][entry] = -1;
              }
          }
  
          nIdCount = 0;
          nTried = 0;
          nNew = 0;
          nLastGood = 1; //Initially at 1 so that "never" is strictly worse.
          mapInfo.clear();
          mapAddr.clear();
      }
  
      CAddrMan()
      {
          Clear();
      }
  
      ~CAddrMan()
      {
          nKey.SetNull();
      }
  
      //! Return the number of (unique) addresses in all tables.
      size_t size() const
      {
          LOCK(cs); // TODO: Cache this in an atomic to avoid this overhead
          return vRandom.size();
      }
  
      //! Consistency check
      void Check()
      {
  #ifdef DEBUG_ADDRMAN
          {
              LOCK(cs);
              int err;
              if ((err=Check_()))
                  LogPrintf("ADDRMAN CONSISTENCY CHECK FAILED!!! err=%i\n", err);
          }
  #endif
      }
  
      //! Add a single address.
      bool Add(const CAddress &addr, const CNetAddr& source, int64_t nTimePenalty = 0)
      {
          LOCK(cs);
          bool fRet = false;
          Check();
          fRet |= Add_(addr, source, nTimePenalty);
          Check();
          if (fRet) {
              LogPrint(BCLog::ADDRMAN, "Added %s from %s: %i tried, %i new\n", addr.ToStringIPPort(), source.ToString(), nTried, nNew);
          }
          return fRet;
      }
  
      //! Add multiple addresses.
      bool Add(const std::vector<CAddress> &vAddr, const CNetAddr& source, int64_t nTimePenalty = 0)
      {
          LOCK(cs);
          int nAdd = 0;
          Check();
          for (std::vector<CAddress>::const_iterator it = vAddr.begin(); it != vAddr.end(); it++)
              nAdd += Add_(*it, source, nTimePenalty) ? 1 : 0;
          Check();
          if (nAdd) {
              LogPrint(BCLog::ADDRMAN, "Added %i addresses from %s: %i tried, %i new\n", nAdd, source.ToString(), nTried, nNew);
          }
          return nAdd > 0;
      }
  
      //! Mark an entry as accessible.
      void Good(const CService &addr, bool test_before_evict = true, int64_t nTime = GetAdjustedTime())
      {
          LOCK(cs);
          Check();
          Good_(addr, test_before_evict, nTime);
          Check();
      }
  
      //! Mark an entry as connection attempted to.
      void Attempt(const CService &addr, bool fCountFailure, int64_t nTime = GetAdjustedTime())
      {
          LOCK(cs);
          Check();
          Attempt_(addr, fCountFailure, nTime);
          Check();
      }
  
      //! See if any to-be-evicted tried table entries have been tested and if so resolve the collisions.
      void ResolveCollisions()
      {
          LOCK(cs);
          Check();
          ResolveCollisions_();
          Check();
      }
  
      //! Randomly select an address in tried that another address is attempting to evict.
      CAddrInfo SelectTriedCollision()
      {
          CAddrInfo ret;
          {
              LOCK(cs);
              Check();
              ret = SelectTriedCollision_();
              Check();
          }
          return ret;
      }
  
      /**
       * Choose an address to connect to.
       */
      CAddrInfo Select(bool newOnly = false)
      {
          CAddrInfo addrRet;
          {
              LOCK(cs);
              Check();
              addrRet = Select_(newOnly);
              Check();
          }
          return addrRet;
      }
  
      //! Return a bunch of addresses, selected at random.
      std::vector<CAddress> GetAddr(size_t max_addresses, size_t max_pct)
      {
          Check();
          std::vector<CAddress> vAddr;
          {
              LOCK(cs);
              GetAddr_(vAddr, max_addresses, max_pct);
          }
          Check();
          return vAddr;
      }
  
      //! Mark an entry as currently-connected-to.
      void Connected(const CService &addr, int64_t nTime = GetAdjustedTime())
      {
          LOCK(cs);
          Check();
          Connected_(addr, nTime);
          Check();
      }
  
      void SetServices(const CService &addr, ServiceFlags nServices)
      {
          LOCK(cs);
          Check();
          SetServices_(addr, nServices);
          Check();
      }
  
  };
  
  #endif // RUVCHAIN_ADDRMAN_H
  