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 class CBlockIndex;
  19 class CCoinsViewDBCursor;
  20 class uint256;
  21
  22 //! No need to periodic flush if at least this much space still available.
  23 static constexpr int MAX_BLOCK_COINSDB_USAGE = 10;
  24 //! -dbcache default (MiB)
  25 static const int64_t nDefaultDbCache = 450;
  26 //! -dbbatchsize default (bytes)
  27 static const int64_t nDefaultDbBatchSize = 16 << 20;
  28 //! max. -dbcache (MiB)
  29 static const int64_t nMaxDbCache = sizeof(void*) > 4 ? 16384 : 1024;
  30 //! min. -dbcache (MiB)
  31 static const int64_t nMinDbCache = 4;
  32 //! Max memory allocated to block tree DB specific cache, if no -txindex (MiB)
  33 static const int64_t nMaxBlockDBCache = 2;
  34 //! Max memory allocated to block tree DB specific cache, if -txindex (MiB)
  35 // Unlike for the UTXO database, for the txindex scenario the leveldb cache make
  36 // a meaningful difference: https://github.com/bitcoin/bitcoin/pull/8273#issuecomment-229601991
  37 static const int64_t nMaxBlockDBAndTxIndexCache = 1024;
  38 //! Max memory allocated to coin DB specific cache (MiB)
  39 static const int64_t nMaxCoinsDBCache = 8;
  40
  41 struct CDiskTxPos : public CDiskBlockPos
  42 {
  43     unsigned int nTxOffset; // after header
  44
  45     ADD_SERIALIZE_METHODS;
  46
  47     template <typename Stream, typename Operation>
  48     inline void SerializationOp(Stream& s, Operation ser_action) {
  49         READWRITE(*(CDiskBlockPos*)this);
  50         READWRITE(VARINT(nTxOffset));
  51     }
  52
  53     CDiskTxPos(const CDiskBlockPos &blockIn, unsigned int nTxOffsetIn) : CDiskBlockPos(blockIn.nFile, blockIn.nPos), nTxOffset(nTxOffsetIn) {
  54     }
  55
  56     CDiskTxPos() {
  57         SetNull();
  58     }
  59
  60     void SetNull() {
  61         CDiskBlockPos::SetNull();
  62         nTxOffset = 0;
  63     }
  64 };
  65
  66 /** CCoinsView backed by the coin database (chainstate/) */
  67 class CCoinsViewDB : public CCoinsView
  68 {
  69 protected:
  70     CDBWrapper db;
  71 public:
  72     CCoinsViewDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
  73
  74     bool GetCoin(const COutPoint &outpoint, Coin &coin) const override;
  75     bool HaveCoin(const COutPoint &outpoint) const override;
  76     uint256 GetBestBlock() const override;
  77     std::vector<uint256> GetHeadBlocks() const override;
  78     bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) override;
  79     CCoinsViewCursor *Cursor() const override;
  80
  81     //! Attempt to update from an older database format. Returns whether an error occurred.
  82     bool Upgrade();
  83     size_t EstimateSize() const override;
  84 };
  85
  86 /** Specialization of CCoinsViewCursor to iterate over a CCoinsViewDB */
  87 class CCoinsViewDBCursor: public CCoinsViewCursor
  88 {
  89 public:
  90     ~CCoinsViewDBCursor() {}
  91
  92     bool GetKey(COutPoint &key) const;
  93     bool GetValue(Coin &coin) const;
  94     unsigned int GetValueSize() const;
  95
  96     bool Valid() const;
  97     void Next();
  98
  99 private:
 100     CCoinsViewDBCursor(CDBIterator* pcursorIn, const uint256 &hashBlockIn):
 101         CCoinsViewCursor(hashBlockIn), pcursor(pcursorIn) {}
 102     std::unique_ptr<CDBIterator> pcursor;
 103     std::pair<char, COutPoint> keyTmp;
 104
 105     friend class CCoinsViewDB;
 106 };
 107
 108 /** Access to the block database (blocks/index/) */
 109 class CBlockTreeDB : public CDBWrapper
 110 {
 111 public:
 112     CBlockTreeDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
 113 private:
 114     CBlockTreeDB(const CBlockTreeDB&);
 115     void operator=(const CBlockTreeDB&);
 116 public:
 117     bool WriteBatchSync(const std::vector<std::pair<int, const CBlockFileInfo*> >& fileInfo, int nLastFile, const std::vector<const CBlockIndex*>& blockinfo);
 118     bool ReadBlockFileInfo(int nFile, CBlockFileInfo &fileinfo);
 119     bool ReadLastBlockFile(int &nFile);
 120     bool WriteReindexing(bool fReindex);
 121     bool ReadReindexing(bool &fReindex);
 122     bool ReadTxIndex(const uint256 &txid, CDiskTxPos &pos);
 123     bool WriteTxIndex(const std::vector<std::pair<uint256, CDiskTxPos> > &list);
 124     bool WriteFlag(const std::string &name, bool fValue);
 125     bool ReadFlag(const std::string &name, bool &fValue);
 126     bool LoadBlockIndexGuts(const Consensus::Params& consensusParams, std::function<CBlockIndex*(const uint256&)> insertBlockIndex);
 127 };
 128
 129 #endif // BITCOIN_TXDB_H