src/txdb.h

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2016 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #ifndef BITCOIN_TXDB_H
   7 #define BITCOIN_TXDB_H
   8
   9 #include "coins.h"
  10 #include "dbwrapper.h"
  11 #include "chain.h"
  12
  13 #include <map>
  14 #include <string>
  15 #include <utility>
  16 #include <vector>
  17
  18 #include <boost/function.hpp>
  19
  20 class CBlockIndex;
  21 class CCoinsViewDBCursor;
  22 class uint256;
  23
  24 //! -dbcache default (MiB)
  25 static const int64_t nDefaultDbCache = 300;
  26 //! max. -dbcache (MiB)
  27 static const int64_t nMaxDbCache = sizeof(void*) > 4 ? 16384 : 1024;
  28 //! min. -dbcache (MiB)
  29 static const int64_t nMinDbCache = 4;
  30 //! Max memory allocated to block tree DB specific cache, if no -txindex (MiB)
  31 static const int64_t nMaxBlockDBCache = 2;
  32 //! Max memory allocated to block tree DB specific cache, if -txindex (MiB)
  33 // Unlike for the UTXO database, for the txindex scenario the leveldb cache make
  34 // a meaningful difference: https://github.com/bitcoin/bitcoin/pull/8273#issuecomment-229601991
  35 static const int64_t nMaxBlockDBAndTxIndexCache = 1024;
  36 //! Max memory allocated to coin DB specific cache (MiB)
  37 static const int64_t nMaxCoinsDBCache = 8;
  38
  39 struct CDiskTxPos : public CDiskBlockPos
  40 {
  41     unsigned int nTxOffset; // after header
  42
  43     ADD_SERIALIZE_METHODS;
  44
  45     template <typename Stream, typename Operation>
  46     inline void SerializationOp(Stream& s, Operation ser_action) {
  47         READWRITE(*(CDiskBlockPos*)this);
  48         READWRITE(VARINT(nTxOffset));
  49     }
  50
  51     CDiskTxPos(const CDiskBlockPos &blockIn, unsigned int nTxOffsetIn) : CDiskBlockPos(blockIn.nFile, blockIn.nPos), nTxOffset(nTxOffsetIn) {
  52     }
  53
  54     CDiskTxPos() {
  55         SetNull();
  56     }
  57
  58     void SetNull() {
  59         CDiskBlockPos::SetNull();
  60         nTxOffset = 0;
  61     }
  62 };
  63
  64 /** CCoinsView backed by the coin database (chainstate/) */
  65 class CCoinsViewDB : public CCoinsView
  66 {
  67 protected:
  68     CDBWrapper db;
  69 public:
  70     CCoinsViewDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
  71
  72     bool GetCoins(const uint256 &txid, CCoins &coins) const;
  73     bool HaveCoins(const uint256 &txid) const;
  74     uint256 GetBestBlock() const;
  75     bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
  76     CCoinsViewCursor *Cursor() const;
  77 };
  78
  79 /** Specialization of CCoinsViewCursor to iterate over a CCoinsViewDB */
  80 class CCoinsViewDBCursor: public CCoinsViewCursor
  81 {
  82 public:
  83     ~CCoinsViewDBCursor() {}
  84
  85     bool GetKey(uint256 &key) const;
  86     bool GetValue(CCoins &coins) const;
  87     unsigned int GetValueSize() const;
  88
  89     bool Valid() const;
  90     void Next();
  91
  92 private:
  93     CCoinsViewDBCursor(CDBIterator* pcursorIn, const uint256 &hashBlockIn):
  94         CCoinsViewCursor(hashBlockIn), pcursor(pcursorIn) {}
  95     std::unique_ptr<CDBIterator> pcursor;
  96     std::pair<char, uint256> keyTmp;
  97
  98     friend class CCoinsViewDB;
  99 };
 100
 101 /** Access to the block database (blocks/index/) */
 102 class CBlockTreeDB : public CDBWrapper
 103 {
 104 public:
 105     CBlockTreeDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
 106 private:
 107     CBlockTreeDB(const CBlockTreeDB&);
 108     void operator=(const CBlockTreeDB&);
 109 public:
 110     bool WriteBatchSync(const std::vector<std::pair<int, const CBlockFileInfo*> >& fileInfo, int nLastFile, const std::vector<const CBlockIndex*>& blockinfo);
 111     bool ReadBlockFileInfo(int nFile, CBlockFileInfo &fileinfo);
 112     bool ReadLastBlockFile(int &nFile);
 113     bool WriteReindexing(bool fReindex);
 114     bool ReadReindexing(bool &fReindex);
 115     bool ReadTxIndex(const uint256 &txid, CDiskTxPos &pos);
 116     bool WriteTxIndex(const std::vector<std::pair<uint256, CDiskTxPos> > &list);
 117     bool WriteFlag(const std::string &name, bool fValue);
 118     bool ReadFlag(const std::string &name, bool &fValue);
 119     bool LoadBlockIndexGuts(boost::function<CBlockIndex*(const uint256&)> insertBlockIndex);
 120 };
 121
 122 #endif // BITCOIN_TXDB_H