src/txdb.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2015 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 #include "txdb.h"
   7
   8 #include "chainparams.h"
   9 #include "hash.h"
  10 #include "pow.h"
  11 #include "uint256.h"
  12
  13 #include <stdint.h>
  14
  15 #include <boost/thread.hpp>
  16
  17 using namespace std;
  18
  19 static const char DB_COINS = 'c';
  20 static const char DB_BLOCK_FILES = 'f';
  21 static const char DB_TXINDEX = 't';
  22 static const char DB_BLOCK_INDEX = 'b';
  23
  24 static const char DB_BEST_BLOCK = 'B';
  25 static const char DB_FLAG = 'F';
  26 static const char DB_REINDEX_FLAG = 'R';
  27 static const char DB_LAST_BLOCK = 'l';
  28
  29
  30 CCoinsViewDB::CCoinsViewDB(size_t nCacheSize, bool fMemory, bool fWipe) : db(GetDataDir() / "chainstate", nCacheSize, fMemory, fWipe, true)
  31 {
  32 }
  33
  34 bool CCoinsViewDB::GetCoins(const uint256 &txid, CCoins &coins) const {
  35     return db.Read(make_pair(DB_COINS, txid), coins);
  36 }
  37
  38 bool CCoinsViewDB::HaveCoins(const uint256 &txid) const {
  39     return db.Exists(make_pair(DB_COINS, txid));
  40 }
  41
  42 uint256 CCoinsViewDB::GetBestBlock() const {
  43     uint256 hashBestChain;
  44     if (!db.Read(DB_BEST_BLOCK, hashBestChain))
  45         return uint256();
  46     return hashBestChain;
  47 }
  48
  49 bool CCoinsViewDB::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) {
  50     CDBBatch batch(db);
  51     size_t count = 0;
  52     size_t changed = 0;
  53     for (CCoinsMap::iterator it = mapCoins.begin(); it != mapCoins.end();) {
  54         if (it->second.flags & CCoinsCacheEntry::DIRTY) {
  55             if (it->second.coins.IsPruned())
  56                 batch.Erase(make_pair(DB_COINS, it->first));
  57             else
  58                 batch.Write(make_pair(DB_COINS, it->first), it->second.coins);
  59             changed++;
  60         }
  61         count++;
  62         CCoinsMap::iterator itOld = it++;
  63         mapCoins.erase(itOld);
  64     }
  65     if (!hashBlock.IsNull())
  66         batch.Write(DB_BEST_BLOCK, hashBlock);
  67
  68     LogPrint("coindb", "Committing %u changed transactions (out of %u) to coin database...\n", (unsigned int)changed, (unsigned int)count);
  69     return db.WriteBatch(batch);
  70 }
  71
  72 CBlockTreeDB::CBlockTreeDB(size_t nCacheSize, bool fMemory, bool fWipe) : CDBWrapper(GetDataDir() / "blocks" / "index", nCacheSize, fMemory, fWipe) {
  73 }
  74
  75 bool CBlockTreeDB::ReadBlockFileInfo(int nFile, CBlockFileInfo &info) {
  76     return Read(make_pair(DB_BLOCK_FILES, nFile), info);
  77 }
  78
  79 bool CBlockTreeDB::WriteReindexing(bool fReindexing) {
  80     if (fReindexing)
  81         return Write(DB_REINDEX_FLAG, '1');
  82     else
  83         return Erase(DB_REINDEX_FLAG);
  84 }
  85
  86 bool CBlockTreeDB::ReadReindexing(bool &fReindexing) {
  87     fReindexing = Exists(DB_REINDEX_FLAG);
  88     return true;
  89 }
  90
  91 bool CBlockTreeDB::ReadLastBlockFile(int &nFile) {
  92     return Read(DB_LAST_BLOCK, nFile);
  93 }
  94
  95 CCoinsViewCursor *CCoinsViewDB::Cursor() const
  96 {
  97     CCoinsViewDBCursor *i = new CCoinsViewDBCursor(const_cast<CDBWrapper*>(&db)->NewIterator(), GetBestBlock());
  98     /* It seems that there are no "const iterators" for LevelDB.  Since we
  99        only need read operations on it, use a const-cast to get around
 100        that restriction.  */
 101     i->pcursor->Seek(DB_COINS);
 102     // Cache key of first record
 103     i->pcursor->GetKey(i->keyTmp);
 104     return i;
 105 }
 106
 107 bool CCoinsViewDBCursor::GetKey(uint256 &key) const
 108 {
 109     // Return cached key
 110     if (keyTmp.first == DB_COINS) {
 111         key = keyTmp.second;
 112         return true;
 113     }
 114     return false;
 115 }
 116
 117 bool CCoinsViewDBCursor::GetValue(CCoins &coins) const
 118 {
 119     return pcursor->GetValue(coins);
 120 }
 121
 122 unsigned int CCoinsViewDBCursor::GetValueSize() const
 123 {
 124     return pcursor->GetValueSize();
 125 }
 126
 127 bool CCoinsViewDBCursor::Valid() const
 128 {
 129     return keyTmp.first == DB_COINS;
 130 }
 131
 132 void CCoinsViewDBCursor::Next()
 133 {
 134     pcursor->Next();
 135     if (!pcursor->Valid() || !pcursor->GetKey(keyTmp))
 136         keyTmp.first = 0; // Invalidate cached key after last record so that Valid() and GetKey() return false
 137 }
 138
 139 bool CBlockTreeDB::WriteBatchSync(const std::vector<std::pair<int, const CBlockFileInfo*> >& fileInfo, int nLastFile, const std::vector<const CBlockIndex*>& blockinfo) {
 140     CDBBatch batch(*this);
 141     for (std::vector<std::pair<int, const CBlockFileInfo*> >::const_iterator it=fileInfo.begin(); it != fileInfo.end(); it++) {
 142         batch.Write(make_pair(DB_BLOCK_FILES, it->first), *it->second);
 143     }
 144     batch.Write(DB_LAST_BLOCK, nLastFile);
 145     for (std::vector<const CBlockIndex*>::const_iterator it=blockinfo.begin(); it != blockinfo.end(); it++) {
 146         batch.Write(make_pair(DB_BLOCK_INDEX, (*it)->GetBlockHash()), CDiskBlockIndex(*it));
 147     }
 148     return WriteBatch(batch, true);
 149 }
 150
 151 bool CBlockTreeDB::ReadTxIndex(const uint256 &txid, CDiskTxPos &pos) {
 152     return Read(make_pair(DB_TXINDEX, txid), pos);
 153 }
 154
 155 bool CBlockTreeDB::WriteTxIndex(const std::vector<std::pair<uint256, CDiskTxPos> >&vect) {
 156     CDBBatch batch(*this);
 157     for (std::vector<std::pair<uint256,CDiskTxPos> >::const_iterator it=vect.begin(); it!=vect.end(); it++)
 158         batch.Write(make_pair(DB_TXINDEX, it->first), it->second);
 159     return WriteBatch(batch);
 160 }
 161
 162 bool CBlockTreeDB::WriteFlag(const std::string &name, bool fValue) {
 163     return Write(std::make_pair(DB_FLAG, name), fValue ? '1' : '0');
 164 }
 165
 166 bool CBlockTreeDB::ReadFlag(const std::string &name, bool &fValue) {
 167     char ch;
 168     if (!Read(std::make_pair(DB_FLAG, name), ch))
 169         return false;
 170     fValue = ch == '1';
 171     return true;
 172 }
 173
 174 bool CBlockTreeDB::LoadBlockIndexGuts(boost::function<CBlockIndex*(const uint256&)> insertBlockIndex)
 175 {
 176     std::unique_ptr<CDBIterator> pcursor(NewIterator());
 177
 178     pcursor->Seek(make_pair(DB_BLOCK_INDEX, uint256()));
 179
 180     // Load mapBlockIndex
 181     while (pcursor->Valid()) {
 182         boost::this_thread::interruption_point();
 183         std::pair<char, uint256> key;
 184         if (pcursor->GetKey(key) && key.first == DB_BLOCK_INDEX) {
 185             CDiskBlockIndex diskindex;
 186             if (pcursor->GetValue(diskindex)) {
 187                 // Construct block index object
 188                 CBlockIndex* pindexNew = insertBlockIndex(diskindex.GetBlockHash());
 189                 pindexNew->pprev          = insertBlockIndex(diskindex.hashPrev);
 190                 pindexNew->nHeight        = diskindex.nHeight;
 191                 pindexNew->nFile          = diskindex.nFile;
 192                 pindexNew->nDataPos       = diskindex.nDataPos;
 193                 pindexNew->nUndoPos       = diskindex.nUndoPos;
 194                 pindexNew->nVersion       = diskindex.nVersion;
 195                 pindexNew->hashMerkleRoot = diskindex.hashMerkleRoot;
 196                 pindexNew->nTime          = diskindex.nTime;
 197                 pindexNew->nBits          = diskindex.nBits;
 198                 pindexNew->nNonce         = diskindex.nNonce;
 199                 pindexNew->nStatus        = diskindex.nStatus;
 200                 pindexNew->nTx            = diskindex.nTx;
 201
 202                 if (!CheckProofOfWork(pindexNew->GetBlockHash(), pindexNew->nBits, Params().GetConsensus()))
 203                     return error("LoadBlockIndex(): CheckProofOfWork failed: %s", pindexNew->ToString());
 204
 205                 pcursor->Next();
 206             } else {
 207                 return error("LoadBlockIndex() : failed to read value");
 208             }
 209         } else {
 210             break;
 211         }
 212     }
 213
 214     return true;
 215 }