1 files changed, 76 insertions, 108 deletions

diff --git a/src/txdb.cpp b/src/txdb.cpp
index ff87655c3..b27ad8010 100644
--- a/src/txdb.cpp
+++ b/src/txdb.cpp
@@ -1,6 +1,5 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2014 The Bitcoin Core developers
-// Copyright (c) 2014-2015 The Dogecoin Core developers
+// Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -8,17 +7,13 @@
 
 #include "chainparams.h"
 #include "hash.h"
-#include "main.h"
 #include "pow.h"
 #include "uint256.h"
-#include "arith_uint256.h"
 
 #include <stdint.h>
 
 #include <boost/thread.hpp>
 
-using namespace std;
-
 static const char DB_COINS = 'c';
 static const char DB_BLOCK_FILES = 'f';
 static const char DB_TXINDEX = 't';
@@ -30,26 +25,16 @@ static const char DB_REINDEX_FLAG = 'R';
 static const char DB_LAST_BLOCK = 'l';
 
 
-void static BatchWriteCoins(CLevelDBBatch &batch, const uint256 &hash, const CCoins &coins) {
-    if (coins.IsPruned())
-        batch.Erase(make_pair(DB_COINS, hash));
-    else
-        batch.Write(make_pair(DB_COINS, hash), coins);
-}
-
-void static BatchWriteHashBestChain(CLevelDBBatch &batch, const uint256 &hash) {
-    batch.Write(DB_BEST_BLOCK, hash);
-}
-
-CCoinsViewDB::CCoinsViewDB(size_t nCacheSize, bool fMemory, bool fWipe) : db(GetDataDir() / "chainstate", nCacheSize, fMemory, fWipe) {
+CCoinsViewDB::CCoinsViewDB(size_t nCacheSize, bool fMemory, bool fWipe) : db(GetDataDir() / "chainstate", nCacheSize, fMemory, fWipe, true) 
+{
 }
 
 bool CCoinsViewDB::GetCoins(const uint256 &txid, CCoins &coins) const {
-    return db.Read(make_pair(DB_COINS, txid), coins);
+    return db.Read(std::make_pair(DB_COINS, txid), coins);
 }
 
 bool CCoinsViewDB::HaveCoins(const uint256 &txid) const {
-    return db.Exists(make_pair(DB_COINS, txid));
+    return db.Exists(std::make_pair(DB_COINS, txid));
 }
 
 uint256 CCoinsViewDB::GetBestBlock() const {
@@ -60,12 +45,15 @@ uint256 CCoinsViewDB::GetBestBlock() const {
 }
 
 bool CCoinsViewDB::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) {
-    CLevelDBBatch batch;
+    CDBBatch batch(db);
     size_t count = 0;
     size_t changed = 0;
     for (CCoinsMap::iterator it = mapCoins.begin(); it != mapCoins.end();) {
         if (it->second.flags & CCoinsCacheEntry::DIRTY) {
-            BatchWriteCoins(batch, it->first, it->second.coins);
+            if (it->second.coins.IsPruned())
+                batch.Erase(std::make_pair(DB_COINS, it->first));
+            else
+                batch.Write(std::make_pair(DB_COINS, it->first), it->second.coins);
             changed++;
         }
         count++;
@@ -73,17 +61,17 @@ bool CCoinsViewDB::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) {
         mapCoins.erase(itOld);
     }
     if (!hashBlock.IsNull())
-        BatchWriteHashBestChain(batch, hashBlock);
+        batch.Write(DB_BEST_BLOCK, hashBlock);
 
     LogPrint("coindb", "Committing %u changed transactions (out of %u) to coin database...\n", (unsigned int)changed, (unsigned int)count);
     return db.WriteBatch(batch);
 }
 
-CBlockTreeDB::CBlockTreeDB(size_t nCacheSize, bool fMemory, bool fWipe) : CLevelDBWrapper(GetDataDir() / "blocks" / "index", nCacheSize, fMemory, fWipe) {
+CBlockTreeDB::CBlockTreeDB(size_t nCacheSize, bool fMemory, bool fWipe) : CDBWrapper(GetDataDir() / "blocks" / "index", nCacheSize, fMemory, fWipe) {
 }
 
 bool CBlockTreeDB::ReadBlockFileInfo(int nFile, CBlockFileInfo &info) {
-    return Read(make_pair(DB_BLOCK_FILES, nFile), info);
+    return Read(std::make_pair(DB_BLOCK_FILES, nFile), info);
 }
 
 bool CBlockTreeDB::WriteReindexing(bool fReindexing) {
@@ -102,79 +90,74 @@ bool CBlockTreeDB::ReadLastBlockFile(int &nFile) {
     return Read(DB_LAST_BLOCK, nFile);
 }
 
-bool CCoinsViewDB::GetStats(CCoinsStats &stats) const {
+CCoinsViewCursor *CCoinsViewDB::Cursor() const
+{
+    CCoinsViewDBCursor *i = new CCoinsViewDBCursor(const_cast<CDBWrapper*>(&db)->NewIterator(), GetBestBlock());
     /* It seems that there are no "const iterators" for LevelDB.  Since we
        only need read operations on it, use a const-cast to get around
        that restriction.  */
-    boost::scoped_ptr<leveldb::Iterator> pcursor(const_cast<CLevelDBWrapper*>(&db)->NewIterator());
-    pcursor->SeekToFirst();
+    i->pcursor->Seek(DB_COINS);
+    // Cache key of first record
+    if (i->pcursor->Valid()) {
+        i->pcursor->GetKey(i->keyTmp);
+    } else {
+        i->keyTmp.first = 0; // Make sure Valid() and GetKey() return false
+    }
+    return i;
+}
 
-    CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);
-    stats.hashBlock = GetBestBlock();
-    ss << stats.hashBlock;
-    arith_uint256 nTotalAmount = 0;
-    while (pcursor->Valid()) {
-        boost::this_thread::interruption_point();
-        try {
-            leveldb::Slice slKey = pcursor->key();
-            CDataStream ssKey(slKey.data(), slKey.data()+slKey.size(), SER_DISK, CLIENT_VERSION);
-            char chType;
-            ssKey >> chType;
-            if (chType == DB_COINS) {
-                leveldb::Slice slValue = pcursor->value();
-                CDataStream ssValue(slValue.data(), slValue.data()+slValue.size(), SER_DISK, CLIENT_VERSION);
-                CCoins coins;
-                ssValue >> coins;
-                uint256 txhash;
-                ssKey >> txhash;
-                ss << txhash;
-                ss << VARINT(coins.nVersion);
-                ss << (coins.fCoinBase ? 'c' : 'n');
-                ss << VARINT(coins.nHeight);
-                stats.nTransactions++;
-                for (unsigned int i=0; i<coins.vout.size(); i++) {
-                    const CTxOut &out = coins.vout[i];
-                    if (!out.IsNull()) {
-                        stats.nTransactionOutputs++;
-                        ss << VARINT(i+1);
-                        ss << out;
-                        nTotalAmount += out.nValue;
-                    }
-                }
-                stats.nSerializedSize += 32 + slValue.size();
-                ss << VARINT(0);
-            }
-            pcursor->Next();
-        } catch (const std::exception& e) {
-            return error("%s: Deserialize or I/O error - %s", __func__, e.what());
-        }
+bool CCoinsViewDBCursor::GetKey(uint256 &key) const
+{
+    // Return cached key
+    if (keyTmp.first == DB_COINS) {
+        key = keyTmp.second;
+        return true;
     }
-    stats.nHeight = mapBlockIndex.find(GetBestBlock())->second->nHeight;
-    stats.hashSerialized = ss.GetHash();
-    stats.nTotalAmount = nTotalAmount;
-    return true;
+    return false;
+}
+
+bool CCoinsViewDBCursor::GetValue(CCoins &coins) const
+{
+    return pcursor->GetValue(coins);
+}
+
+unsigned int CCoinsViewDBCursor::GetValueSize() const
+{
+    return pcursor->GetValueSize();
+}
+
+bool CCoinsViewDBCursor::Valid() const
+{
+    return keyTmp.first == DB_COINS;
+}
+
+void CCoinsViewDBCursor::Next()
+{
+    pcursor->Next();
+    if (!pcursor->Valid() || !pcursor->GetKey(keyTmp))
+        keyTmp.first = 0; // Invalidate cached key after last record so that Valid() and GetKey() return false
 }
 
 bool CBlockTreeDB::WriteBatchSync(const std::vector<std::pair<int, const CBlockFileInfo*> >& fileInfo, int nLastFile, const std::vector<const CBlockIndex*>& blockinfo) {
-    CLevelDBBatch batch;
+    CDBBatch batch(*this);
     for (std::vector<std::pair<int, const CBlockFileInfo*> >::const_iterator it=fileInfo.begin(); it != fileInfo.end(); it++) {
-        batch.Write(make_pair(DB_BLOCK_FILES, it->first), *it->second);
+        batch.Write(std::make_pair(DB_BLOCK_FILES, it->first), *it->second);
     }
     batch.Write(DB_LAST_BLOCK, nLastFile);
     for (std::vector<const CBlockIndex*>::const_iterator it=blockinfo.begin(); it != blockinfo.end(); it++) {
-        batch.Write(make_pair(DB_BLOCK_INDEX, (*it)->GetBlockHash()), CDiskBlockIndex(*it));
+        batch.Write(std::make_pair(DB_BLOCK_INDEX, (*it)->GetBlockHash()), CDiskBlockIndex(*it));
     }
     return WriteBatch(batch, true);
 }
 
 bool CBlockTreeDB::ReadTxIndex(const uint256 &txid, CDiskTxPos &pos) {
-    return Read(make_pair(DB_TXINDEX, txid), pos);
+    return Read(std::make_pair(DB_TXINDEX, txid), pos);
 }
 
 bool CBlockTreeDB::WriteTxIndex(const std::vector<std::pair<uint256, CDiskTxPos> >&vect) {
-    CLevelDBBatch batch;
+    CDBBatch batch(*this);
     for (std::vector<std::pair<uint256,CDiskTxPos> >::const_iterator it=vect.begin(); it!=vect.end(); it++)
-        batch.Write(make_pair(DB_TXINDEX, it->first), it->second);
+        batch.Write(std::make_pair(DB_TXINDEX, it->first), it->second);
     return WriteBatch(batch);
 }
 
@@ -190,32 +173,22 @@ bool CBlockTreeDB::ReadFlag(const std::string &name, bool &fValue) {
     return true;
 }
 
-bool CBlockTreeDB::LoadBlockIndexGuts()
+bool CBlockTreeDB::LoadBlockIndexGuts(boost::function<CBlockIndex*(const uint256&)> insertBlockIndex)
 {
-    boost::scoped_ptr<leveldb::Iterator> pcursor(NewIterator());
+    std::unique_ptr<CDBIterator> pcursor(NewIterator());
 
-    CDataStream ssKeySet(SER_DISK, CLIENT_VERSION);
-    ssKeySet << make_pair(DB_BLOCK_INDEX, uint256());
-    pcursor->Seek(ssKeySet.str());
+    pcursor->Seek(std::make_pair(DB_BLOCK_INDEX, uint256()));
 
     // Load mapBlockIndex
     while (pcursor->Valid()) {
         boost::this_thread::interruption_point();
-        try {
-            leveldb::Slice slKey = pcursor->key();
-            CDataStream ssKey(slKey.data(), slKey.data()+slKey.size(), SER_DISK, CLIENT_VERSION);
-            char chType;
-            ssKey >> chType;
-            if (chType == DB_BLOCK_INDEX) {
-                leveldb::Slice slValue = pcursor->value();
-                CDataStream ssValue(slValue.data(), slValue.data()+slValue.size(), SER_DISK, CLIENT_VERSION);
-                CDiskBlockIndex diskindex;
-                ssValue >> diskindex;
-
+        std::pair<char, uint256> key;
+        if (pcursor->GetKey(key) && key.first == DB_BLOCK_INDEX) {
+            CDiskBlockIndex diskindex;
+            if (pcursor->GetValue(diskindex)) {
                 // Construct block index object
-                CBlockIndex* pindexNew = InsertBlockIndex(diskindex.GetBlockHash());
-                pindexNew->pprev          = InsertBlockIndex(diskindex.hashPrev);
-                pindexNew->pauxpow        = diskindex.pauxpow;
+                CBlockIndex* pindexNew = insertBlockIndex(diskindex.GetBlockHash());
+                pindexNew->pprev          = insertBlockIndex(diskindex.hashPrev);
                 pindexNew->nHeight        = diskindex.nHeight;
                 pindexNew->nFile          = diskindex.nFile;
                 pindexNew->nDataPos       = diskindex.nDataPos;
@@ -227,23 +200,18 @@ bool CBlockTreeDB::LoadBlockIndexGuts()
                 pindexNew->nNonce         = diskindex.nNonce;
                 pindexNew->nStatus        = diskindex.nStatus;
                 pindexNew->nTx            = diskindex.nTx;
-                pindexNew->hashBlockPoW   = diskindex.hashBlockPoW;
 
-                if (pindexNew->nVersion.IsAuxpow()) {
-                    if (!diskindex.pauxpow->check(diskindex.GetBlockHash(), pindexNew->nVersion.GetChainId(), Params().GetConsensus(pindexNew->nHeight))) {
-                        return error("LoadBlockIndex(): CheckProofOfWork failed: %s", pindexNew->ToString());
-                    }
-                } else {
-                    if (!CheckProofOfWork(pindexNew->hashBlockPoW, pindexNew->nBits, Params().GetConsensus(pindexNew->nHeight)))
-                        return error("LoadBlockIndex(): CheckProofOfWork failed: %s", pindexNew->ToString());
-                }
+                /* Bitcoin checks the PoW here.  We don't do this because
+                   the CDiskBlockIndex does not contain the auxpow.
+                   This check isn't important, since the data on disk should
+                   already be valid and can be trusted.  */
 
                 pcursor->Next();
             } else {
-                break; // if shutdown requested or finished loading block index
+                return error("LoadBlockIndex() : failed to read value");
             }
-        } catch (const std::exception& e) {
-            return error("%s: Deserialize or I/O error - %s", __func__, e.what());
+        } else {
+            break;
         }
     }