src/db.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2012 The Bitcoin developers
   3 // Distributed under the MIT/X11 software license, see the accompanying
   4 // file license.txt or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #include "headers.h"
   7 #include "db.h"
   8 #include "net.h"
   9 #include <boost/version.hpp>
  10 #include <boost/filesystem.hpp>
  11 #include <boost/filesystem/fstream.hpp>
  12
  13 using namespace std;
  14 using namespace boost;
  15
  16
  17 unsigned int nWalletDBUpdated;
  18 uint64 nAccountingEntryNumber = 0;
  19
  20
  21
  22 //
  23 // CDB
  24 //
  25
  26 static CCriticalSection cs_db;
  27 static bool fDbEnvInit = false;
  28 DbEnv dbenv(0);
  29 static map<string, int> mapFileUseCount;
  30 static map<string, Db*> mapDb;
  31
  32 static void EnvShutdown()
  33 {
  34     if (!fDbEnvInit)
  35         return;
  36
  37     fDbEnvInit = false;
  38     try
  39     {
  40         dbenv.close(0);
  41     }
  42     catch (const DbException& e)
  43     {
  44         printf("EnvShutdown exception: %s (%d)\n", e.what(), e.get_errno());
  45     }
  46     DbEnv(0).remove(GetDataDir().c_str(), 0);
  47 }
  48
  49 class CDBInit
  50 {
  51 public:
  52     CDBInit()
  53     {
  54     }
  55     ~CDBInit()
  56     {
  57         EnvShutdown();
  58     }
  59 }
  60 instance_of_cdbinit;
  61
  62
  63 CDB::CDB(const char* pszFile, const char* pszMode) : pdb(NULL)
  64 {
  65     int ret;
  66     if (pszFile == NULL)
  67         return;
  68
  69     fReadOnly = (!strchr(pszMode, '+') && !strchr(pszMode, 'w'));
  70     bool fCreate = strchr(pszMode, 'c');
  71     unsigned int nFlags = DB_THREAD;
  72     if (fCreate)
  73         nFlags |= DB_CREATE;
  74
  75     {
  76         LOCK(cs_db);
  77         if (!fDbEnvInit)
  78         {
  79             if (fShutdown)
  80                 return;
  81             string strDataDir = GetDataDir();
  82             filesystem::path pathLogDir(strDataDir + "/database");
  83             pathLogDir.make_preferred();
  84             filesystem::create_directory(pathLogDir);
  85             filesystem::path pathErrorFile(strDataDir + "/db.log");
  86             pathErrorFile.make_preferred();
  87             printf("dbenv.open LogDir=%s ErrorFile=%s\n", pathLogDir.string().c_str(), pathErrorFile.string().c_str());
  88
  89             int nDbCache = GetArg("-dbcache", 25);
  90             dbenv.set_lg_dir(pathLogDir.string().c_str());
  91             dbenv.set_cachesize(nDbCache / 1024, (nDbCache % 1024)*1048576, 1);
  92             dbenv.set_lg_bsize(1048576);
  93             dbenv.set_lg_max(10485760);
  94             dbenv.set_lk_max_locks(10000);
  95             dbenv.set_lk_max_objects(10000);
  96             dbenv.set_errfile(fopen(pathErrorFile.string().c_str(), "a")); /// debug
  97             dbenv.set_flags(DB_AUTO_COMMIT, 1);
  98             dbenv.log_set_config(DB_LOG_AUTO_REMOVE, 1);
  99             ret = dbenv.open(strDataDir.c_str(),
 100                              DB_CREATE     |
 101                              DB_INIT_LOCK  |
 102                              DB_INIT_LOG   |
 103                              DB_INIT_MPOOL |
 104                              DB_INIT_TXN   |
 105                              DB_THREAD     |
 106                              DB_RECOVER,
 107                              S_IRUSR | S_IWUSR);
 108             if (ret > 0)
 109                 throw runtime_error(strprintf("CDB() : error %d opening database environment", ret));
 110             fDbEnvInit = true;
 111         }
 112
 113         strFile = pszFile;
 114         ++mapFileUseCount[strFile];
 115         pdb = mapDb[strFile];
 116         if (pdb == NULL)
 117         {
 118             pdb = new Db(&dbenv, 0);
 119
 120             ret = pdb->open(NULL,      // Txn pointer
 121                             pszFile,   // Filename
 122                             "main",    // Logical db name
 123                             DB_BTREE,  // Database type
 124                             nFlags,    // Flags
 125                             0);
 126
 127             if (ret > 0)
 128             {
 129                 delete pdb;
 130                 pdb = NULL;
 131                 {
 132                      LOCK(cs_db);
 133                     --mapFileUseCount[strFile];
 134                 }
 135                 strFile = "";
 136                 throw runtime_error(strprintf("CDB() : can't open database file %s, error %d", pszFile, ret));
 137             }
 138
 139             if (fCreate && !Exists(string("version")))
 140             {
 141                 bool fTmp = fReadOnly;
 142                 fReadOnly = false;
 143                 WriteVersion(CLIENT_VERSION);
 144                 fReadOnly = fTmp;
 145             }
 146
 147             mapDb[strFile] = pdb;
 148         }
 149     }
 150 }
 151
 152 void CDB::Close()
 153 {
 154     if (!pdb)
 155         return;
 156     if (!vTxn.empty())
 157         vTxn.front()->abort();
 158     vTxn.clear();
 159     pdb = NULL;
 160
 161     // Flush database activity from memory pool to disk log
 162     unsigned int nMinutes = 0;
 163     if (fReadOnly)
 164         nMinutes = 1;
 165     if (strFile == "addr.dat")
 166         nMinutes = 2;
 167     if (strFile == "blkindex.dat" && IsInitialBlockDownload())
 168         nMinutes = 5;
 169
 170     dbenv.txn_checkpoint(nMinutes ? GetArg("-dblogsize", 100)*1024 : 0, nMinutes, 0);
 171
 172     {
 173         LOCK(cs_db);
 174         --mapFileUseCount[strFile];
 175     }
 176 }
 177
 178 void static CloseDb(const string& strFile)
 179 {
 180     {
 181         LOCK(cs_db);
 182         if (mapDb[strFile] != NULL)
 183         {
 184             // Close the database handle
 185             Db* pdb = mapDb[strFile];
 186             pdb->close(0);
 187             delete pdb;
 188             mapDb[strFile] = NULL;
 189         }
 190     }
 191 }
 192
 193 bool CDB::Rewrite(const string& strFile, const char* pszSkip)
 194 {
 195     while (!fShutdown)
 196     {
 197         {
 198             LOCK(cs_db);
 199             if (!mapFileUseCount.count(strFile) || mapFileUseCount[strFile] == 0)
 200             {
 201                 // Flush log data to the dat file
 202                 CloseDb(strFile);
 203                 dbenv.txn_checkpoint(0, 0, 0);
 204                 dbenv.lsn_reset(strFile.c_str(), 0);
 205                 mapFileUseCount.erase(strFile);
 206
 207                 bool fSuccess = true;
 208                 printf("Rewriting %s...\n", strFile.c_str());
 209                 string strFileRes = strFile + ".rewrite";
 210                 { // surround usage of db with extra {}
 211                     CDB db(strFile.c_str(), "r");
 212                     Db* pdbCopy = new Db(&dbenv, 0);
 213
 214                     int ret = pdbCopy->open(NULL,                 // Txn pointer
 215                                             strFileRes.c_str(),   // Filename
 216                                             "main",    // Logical db name
 217                                             DB_BTREE,  // Database type
 218                                             DB_CREATE,    // Flags
 219                                             0);
 220                     if (ret > 0)
 221                     {
 222                         printf("Cannot create database file %s\n", strFileRes.c_str());
 223                         fSuccess = false;
 224                     }
 225
 226                     Dbc* pcursor = db.GetCursor();
 227                     if (pcursor)
 228                         while (fSuccess)
 229                         {
 230                             CDataStream ssKey;
 231                             CDataStream ssValue;
 232                             int ret = db.ReadAtCursor(pcursor, ssKey, ssValue, DB_NEXT);
 233                             if (ret == DB_NOTFOUND)
 234                             {
 235                                 pcursor->close();
 236                                 break;
 237                             }
 238                             else if (ret != 0)
 239                             {
 240                                 pcursor->close();
 241                                 fSuccess = false;
 242                                 break;
 243                             }
 244                             if (pszSkip &&
 245                                 strncmp(&ssKey[0], pszSkip, std::min(ssKey.size(), strlen(pszSkip))) == 0)
 246                                 continue;
 247                             if (strncmp(&ssKey[0], "\x07version", 8) == 0)
 248                             {
 249                                 // Update version:
 250                                 ssValue.clear();
 251                                 ssValue << CLIENT_VERSION;
 252                             }
 253                             Dbt datKey(&ssKey[0], ssKey.size());
 254                             Dbt datValue(&ssValue[0], ssValue.size());
 255                             int ret2 = pdbCopy->put(NULL, &datKey, &datValue, DB_NOOVERWRITE);
 256                             if (ret2 > 0)
 257                                 fSuccess = false;
 258                         }
 259                     if (fSuccess)
 260                     {
 261                         db.Close();
 262                         CloseDb(strFile);
 263                         if (pdbCopy->close(0))
 264                             fSuccess = false;
 265                         delete pdbCopy;
 266                     }
 267                 }
 268                 if (fSuccess)
 269                 {
 270                     Db dbA(&dbenv, 0);
 271                     if (dbA.remove(strFile.c_str(), NULL, 0))
 272                         fSuccess = false;
 273                     Db dbB(&dbenv, 0);
 274                     if (dbB.rename(strFileRes.c_str(), NULL, strFile.c_str(), 0))
 275                         fSuccess = false;
 276                 }
 277                 if (!fSuccess)
 278                     printf("Rewriting of %s FAILED!\n", strFileRes.c_str());
 279                 return fSuccess;
 280             }
 281         }
 282         Sleep(100);
 283     }
 284     return false;
 285 }
 286
 287
 288 void DBFlush(bool fShutdown)
 289 {
 290     // Flush log data to the actual data file
 291     //  on all files that are not in use
 292     printf("DBFlush(%s)%s\n", fShutdown ? "true" : "false", fDbEnvInit ? "" : " db not started");
 293     if (!fDbEnvInit)
 294         return;
 295     {
 296         LOCK(cs_db);
 297         map<string, int>::iterator mi = mapFileUseCount.begin();
 298         while (mi != mapFileUseCount.end())
 299         {
 300             string strFile = (*mi).first;
 301             int nRefCount = (*mi).second;
 302             printf("%s refcount=%d\n", strFile.c_str(), nRefCount);
 303             if (nRefCount == 0)
 304             {
 305                 // Move log data to the dat file
 306                 CloseDb(strFile);
 307                 dbenv.txn_checkpoint(0, 0, 0);
 308                 printf("%s flush\n", strFile.c_str());
 309                 dbenv.lsn_reset(strFile.c_str(), 0);
 310                 mapFileUseCount.erase(mi++);
 311             }
 312             else
 313                 mi++;
 314         }
 315         if (fShutdown)
 316         {
 317             char** listp;
 318             if (mapFileUseCount.empty())
 319             {
 320                 dbenv.log_archive(&listp, DB_ARCH_REMOVE);
 321                 EnvShutdown();
 322             }
 323         }
 324     }
 325 }
 326
 327
 328
 329
 330
 331
 332 //
 333 // CTxDB
 334 //
 335
 336 bool CTxDB::ReadTxIndex(uint256 hash, CTxIndex& txindex)
 337 {
 338     assert(!fClient);
 339     txindex.SetNull();
 340     return Read(make_pair(string("tx"), hash), txindex);
 341 }
 342
 343 bool CTxDB::UpdateTxIndex(uint256 hash, const CTxIndex& txindex)
 344 {
 345     assert(!fClient);
 346     return Write(make_pair(string("tx"), hash), txindex);
 347 }
 348
 349 bool CTxDB::AddTxIndex(const CTransaction& tx, const CDiskTxPos& pos, int nHeight)
 350 {
 351     assert(!fClient);
 352
 353     // Add to tx index
 354     uint256 hash = tx.GetHash();
 355     CTxIndex txindex(pos, tx.vout.size());
 356     return Write(make_pair(string("tx"), hash), txindex);
 357 }
 358
 359 bool CTxDB::EraseTxIndex(const CTransaction& tx)
 360 {
 361     assert(!fClient);
 362     uint256 hash = tx.GetHash();
 363
 364     return Erase(make_pair(string("tx"), hash));
 365 }
 366
 367 bool CTxDB::ContainsTx(uint256 hash)
 368 {
 369     assert(!fClient);
 370     return Exists(make_pair(string("tx"), hash));
 371 }
 372
 373 bool CTxDB::ReadOwnerTxes(uint160 hash160, int nMinHeight, vector<CTransaction>& vtx)
 374 {
 375     assert(!fClient);
 376     vtx.clear();
 377
 378     // Get cursor
 379     Dbc* pcursor = GetCursor();
 380     if (!pcursor)
 381         return false;
 382
 383     unsigned int fFlags = DB_SET_RANGE;
 384     loop
 385     {
 386         // Read next record
 387         CDataStream ssKey;
 388         if (fFlags == DB_SET_RANGE)
 389             ssKey << string("owner") << hash160 << CDiskTxPos(0, 0, 0);
 390         CDataStream ssValue;
 391         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
 392         fFlags = DB_NEXT;
 393         if (ret == DB_NOTFOUND)
 394             break;
 395         else if (ret != 0)
 396         {
 397             pcursor->close();
 398             return false;
 399         }
 400
 401         // Unserialize
 402         string strType;
 403         uint160 hashItem;
 404         CDiskTxPos pos;
 405         ssKey >> strType >> hashItem >> pos;
 406         int nItemHeight;
 407         ssValue >> nItemHeight;
 408
 409         // Read transaction
 410         if (strType != "owner" || hashItem != hash160)
 411             break;
 412         if (nItemHeight >= nMinHeight)
 413         {
 414             vtx.resize(vtx.size()+1);
 415             if (!vtx.back().ReadFromDisk(pos))
 416             {
 417                 pcursor->close();
 418                 return false;
 419             }
 420         }
 421     }
 422
 423     pcursor->close();
 424     return true;
 425 }
 426
 427 bool CTxDB::ReadDiskTx(uint256 hash, CTransaction& tx, CTxIndex& txindex)
 428 {
 429     assert(!fClient);
 430     tx.SetNull();
 431     if (!ReadTxIndex(hash, txindex))
 432         return false;
 433     return (tx.ReadFromDisk(txindex.pos));
 434 }
 435
 436 bool CTxDB::ReadDiskTx(uint256 hash, CTransaction& tx)
 437 {
 438     CTxIndex txindex;
 439     return ReadDiskTx(hash, tx, txindex);
 440 }
 441
 442 bool CTxDB::ReadDiskTx(COutPoint outpoint, CTransaction& tx, CTxIndex& txindex)
 443 {
 444     return ReadDiskTx(outpoint.hash, tx, txindex);
 445 }
 446
 447 bool CTxDB::ReadDiskTx(COutPoint outpoint, CTransaction& tx)
 448 {
 449     CTxIndex txindex;
 450     return ReadDiskTx(outpoint.hash, tx, txindex);
 451 }
 452
 453 bool CTxDB::WriteBlockIndex(const CDiskBlockIndex& blockindex)
 454 {
 455     return Write(make_pair(string("blockindex"), blockindex.GetBlockHash()), blockindex);
 456 }
 457
 458 bool CTxDB::EraseBlockIndex(uint256 hash)
 459 {
 460     return Erase(make_pair(string("blockindex"), hash));
 461 }
 462
 463 bool CTxDB::ReadHashBestChain(uint256& hashBestChain)
 464 {
 465     return Read(string("hashBestChain"), hashBestChain);
 466 }
 467
 468 bool CTxDB::WriteHashBestChain(uint256 hashBestChain)
 469 {
 470     return Write(string("hashBestChain"), hashBestChain);
 471 }
 472
 473 bool CTxDB::ReadBestInvalidWork(CBigNum& bnBestInvalidWork)
 474 {
 475     return Read(string("bnBestInvalidWork"), bnBestInvalidWork);
 476 }
 477
 478 bool CTxDB::WriteBestInvalidWork(CBigNum bnBestInvalidWork)
 479 {
 480     return Write(string("bnBestInvalidWork"), bnBestInvalidWork);
 481 }
 482
 483 CBlockIndex static * InsertBlockIndex(uint256 hash)
 484 {
 485     if (hash == 0)
 486         return NULL;
 487
 488     // Return existing
 489     map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hash);
 490     if (mi != mapBlockIndex.end())
 491         return (*mi).second;
 492
 493     // Create new
 494     CBlockIndex* pindexNew = new CBlockIndex();
 495     if (!pindexNew)
 496         throw runtime_error("LoadBlockIndex() : new CBlockIndex failed");
 497     mi = mapBlockIndex.insert(make_pair(hash, pindexNew)).first;
 498     pindexNew->phashBlock = &((*mi).first);
 499
 500     return pindexNew;
 501 }
 502
 503 bool CTxDB::LoadBlockIndex()
 504 {
 505     // Get database cursor
 506     Dbc* pcursor = GetCursor();
 507     if (!pcursor)
 508         return false;
 509
 510     // Load mapBlockIndex
 511     unsigned int fFlags = DB_SET_RANGE;
 512     loop
 513     {
 514         // Read next record
 515         CDataStream ssKey;
 516         if (fFlags == DB_SET_RANGE)
 517             ssKey << make_pair(string("blockindex"), uint256(0));
 518         CDataStream ssValue;
 519         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
 520         fFlags = DB_NEXT;
 521         if (ret == DB_NOTFOUND)
 522             break;
 523         else if (ret != 0)
 524             return false;
 525
 526         // Unserialize
 527         string strType;
 528         ssKey >> strType;
 529         if (strType == "blockindex")
 530         {
 531             CDiskBlockIndex diskindex;
 532             ssValue >> diskindex;
 533
 534             // Construct block index object
 535             CBlockIndex* pindexNew = InsertBlockIndex(diskindex.GetBlockHash());
 536             pindexNew->pprev          = InsertBlockIndex(diskindex.hashPrev);
 537             pindexNew->pnext          = InsertBlockIndex(diskindex.hashNext);
 538             pindexNew->nFile          = diskindex.nFile;
 539             pindexNew->nBlockPos      = diskindex.nBlockPos;
 540             pindexNew->nHeight        = diskindex.nHeight;
 541             pindexNew->nVersion       = diskindex.nVersion;
 542             pindexNew->hashMerkleRoot = diskindex.hashMerkleRoot;
 543             pindexNew->nTime          = diskindex.nTime;
 544             pindexNew->nBits          = diskindex.nBits;
 545             pindexNew->nNonce         = diskindex.nNonce;
 546
 547             // Watch for genesis block
 548             if (pindexGenesisBlock == NULL && diskindex.GetBlockHash() == hashGenesisBlock)
 549                 pindexGenesisBlock = pindexNew;
 550
 551             if (!pindexNew->CheckIndex())
 552                 return error("LoadBlockIndex() : CheckIndex failed at %d", pindexNew->nHeight);
 553         }
 554         else
 555         {
 556             break;
 557         }
 558     }
 559     pcursor->close();
 560
 561     // Calculate bnChainWork
 562     vector<pair<int, CBlockIndex*> > vSortedByHeight;
 563     vSortedByHeight.reserve(mapBlockIndex.size());
 564     BOOST_FOREACH(const PAIRTYPE(uint256, CBlockIndex*)& item, mapBlockIndex)
 565     {
 566         CBlockIndex* pindex = item.second;
 567         vSortedByHeight.push_back(make_pair(pindex->nHeight, pindex));
 568     }
 569     sort(vSortedByHeight.begin(), vSortedByHeight.end());
 570     BOOST_FOREACH(const PAIRTYPE(int, CBlockIndex*)& item, vSortedByHeight)
 571     {
 572         CBlockIndex* pindex = item.second;
 573         pindex->bnChainWork = (pindex->pprev ? pindex->pprev->bnChainWork : 0) + pindex->GetBlockWork();
 574     }
 575
 576     // Load hashBestChain pointer to end of best chain
 577     if (!ReadHashBestChain(hashBestChain))
 578     {
 579         if (pindexGenesisBlock == NULL)
 580             return true;
 581         return error("CTxDB::LoadBlockIndex() : hashBestChain not loaded");
 582     }
 583     if (!mapBlockIndex.count(hashBestChain))
 584         return error("CTxDB::LoadBlockIndex() : hashBestChain not found in the block index");
 585     pindexBest = mapBlockIndex[hashBestChain];
 586     nBestHeight = pindexBest->nHeight;
 587     bnBestChainWork = pindexBest->bnChainWork;
 588     printf("LoadBlockIndex(): hashBestChain=%s  height=%d\n", hashBestChain.ToString().substr(0,20).c_str(), nBestHeight);
 589
 590     // Load bnBestInvalidWork, OK if it doesn't exist
 591     ReadBestInvalidWork(bnBestInvalidWork);
 592
 593     // Verify blocks in the best chain
 594     int nCheckLevel = GetArg("-checklevel", 1);
 595     int nCheckDepth = GetArg( "-checkblocks", 2500);
 596     if (nCheckDepth == 0)
 597         nCheckDepth = 1000000000; // suffices until the year 19000
 598     if (nCheckDepth > nBestHeight)
 599         nCheckDepth = nBestHeight;
 600     printf("Verifying last %i blocks at level %i\n", nCheckDepth, nCheckLevel);
 601     CBlockIndex* pindexFork = NULL;
 602     map<pair<unsigned int, unsigned int>, CBlockIndex*> mapBlockPos;
 603     for (CBlockIndex* pindex = pindexBest; pindex && pindex->pprev; pindex = pindex->pprev)
 604     {
 605         if (pindex->nHeight < nBestHeight-nCheckDepth)
 606             break;
 607         CBlock block;
 608         if (!block.ReadFromDisk(pindex))
 609             return error("LoadBlockIndex() : block.ReadFromDisk failed");
 610         // check level 1: verify block validity
 611         if (nCheckLevel>0 && !block.CheckBlock())
 612         {
 613             printf("LoadBlockIndex() : *** found bad block at %d, hash=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString().c_str());
 614             pindexFork = pindex->pprev;
 615         }
 616         // check level 2: verify transaction index validity
 617         if (nCheckLevel>1)
 618         {
 619             pair<unsigned int, unsigned int> pos = make_pair(pindex->nFile, pindex->nBlockPos);
 620             mapBlockPos[pos] = pindex;
 621             BOOST_FOREACH(const CTransaction &tx, block.vtx)
 622             {
 623                 uint256 hashTx = tx.GetHash();
 624                 CTxIndex txindex;
 625                 if (ReadTxIndex(hashTx, txindex))
 626                 {
 627                     // check level 3: checker transaction hashes
 628                     if (nCheckLevel>2 || pindex->nFile != txindex.pos.nFile || pindex->nBlockPos != txindex.pos.nBlockPos)
 629                     {
 630                         // either an error or a duplicate transaction
 631                         CTransaction txFound;
 632                         if (!txFound.ReadFromDisk(txindex.pos))
 633                         {
 634                             printf("LoadBlockIndex() : *** cannot read mislocated transaction %s\n", hashTx.ToString().c_str());
 635                             pindexFork = pindex->pprev;
 636                         }
 637                         else
 638                             if (txFound.GetHash() != hashTx) // not a duplicate tx
 639                             {
 640                                 printf("LoadBlockIndex(): *** invalid tx position for %s\n", hashTx.ToString().c_str());
 641                                 pindexFork = pindex->pprev;
 642                             }
 643                     }
 644                     // check level 4: check whether spent txouts were spent within the main chain
 645                     int nOutput = 0;
 646                     if (nCheckLevel>3)
 647                         BOOST_FOREACH(const CDiskTxPos &txpos, txindex.vSpent)
 648                         {
 649                             if (!txpos.IsNull())
 650                             {
 651                                 pair<unsigned int, unsigned int> posFind = make_pair(txpos.nFile, txpos.nBlockPos);
 652                                 if (!mapBlockPos.count(posFind))
 653                                 {
 654                                     printf("LoadBlockIndex(): *** found bad spend at %d, hashBlock=%s, hashTx=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString().c_str(), hashTx.ToString().c_str());
 655                                     pindexFork = pindex->pprev;
 656                                 }
 657                                 // check level 6: check whether spent txouts were spent by a valid transaction that consume them
 658                                 if (nCheckLevel>5)
 659                                 {
 660                                     CTransaction txSpend;
 661                                     if (!txSpend.ReadFromDisk(txpos))
 662                                     {
 663                                         printf("LoadBlockIndex(): *** cannot read spending transaction of %s:%i from disk\n", hashTx.ToString().c_str(), nOutput);
 664                                         pindexFork = pindex->pprev;
 665                                     }
 666                                     else if (!txSpend.CheckTransaction())
 667                                     {
 668                                         printf("LoadBlockIndex(): *** spending transaction of %s:%i is invalid\n", hashTx.ToString().c_str(), nOutput);
 669                                         pindexFork = pindex->pprev;
 670                                     }
 671                                     else
 672                                     {
 673                                         bool fFound = false;
 674                                         BOOST_FOREACH(const CTxIn &txin, txSpend.vin)
 675                                             if (txin.prevout.hash == hashTx && txin.prevout.n == nOutput)
 676                                                 fFound = true;
 677                                         if (!fFound)
 678                                         {
 679                                             printf("LoadBlockIndex(): *** spending transaction of %s:%i does not spend it\n", hashTx.ToString().c_str(), nOutput);
 680                                             pindexFork = pindex->pprev;
 681                                         }
 682                                     }
 683                                 }
 684                             }
 685                             nOutput++;
 686                         }
 687                 }
 688                 // check level 5: check whether all prevouts are marked spent
 689                 if (nCheckLevel>4)
 690                      BOOST_FOREACH(const CTxIn &txin, tx.vin)
 691                      {
 692                           CTxIndex txindex;
 693                           if (ReadTxIndex(txin.prevout.hash, txindex))
 694                               if (txindex.vSpent.size()-1 < txin.prevout.n || txindex.vSpent[txin.prevout.n].IsNull())
 695                               {
 696                                   printf("LoadBlockIndex(): *** found unspent prevout %s:%i in %s\n", txin.prevout.hash.ToString().c_str(), txin.prevout.n, hashTx.ToString().c_str());
 697                                   pindexFork = pindex->pprev;
 698                               }
 699                      }
 700             }
 701         }
 702     }
 703     if (pindexFork)
 704     {
 705         // Reorg back to the fork
 706         printf("LoadBlockIndex() : *** moving best chain pointer back to block %d\n", pindexFork->nHeight);
 707         CBlock block;
 708         if (!block.ReadFromDisk(pindexFork))
 709             return error("LoadBlockIndex() : block.ReadFromDisk failed");
 710         CTxDB txdb;
 711         block.SetBestChain(txdb, pindexFork);
 712     }
 713
 714     return true;
 715 }
 716
 717
 718
 719
 720
 721 //
 722 // CAddrDB
 723 //
 724
 725 bool CAddrDB::WriteAddrman(const CAddrMan& addrman)
 726 {
 727     return Write(string("addrman"), addrman);
 728 }
 729
 730 bool CAddrDB::LoadAddresses()
 731 {
 732     if (Read(string("addrman"), addrman))
 733     {
 734         printf("Loaded %i addresses\n", addrman.size());
 735         return true;
 736     }
 737
 738     // Read pre-0.6 addr records
 739
 740     vector<CAddress> vAddr;
 741     vector<vector<unsigned char> > vDelete;
 742
 743     // Get cursor
 744     Dbc* pcursor = GetCursor();
 745     if (!pcursor)
 746         return false;
 747
 748     loop
 749     {
 750         // Read next record
 751         CDataStream ssKey;
 752         CDataStream ssValue;
 753         int ret = ReadAtCursor(pcursor, ssKey, ssValue);
 754         if (ret == DB_NOTFOUND)
 755             break;
 756         else if (ret != 0)
 757             return false;
 758
 759         // Unserialize
 760         string strType;
 761         ssKey >> strType;
 762         if (strType == "addr")
 763         {
 764             CAddress addr;
 765             ssValue >> addr;
 766             vAddr.push_back(addr);
 767         }
 768     }
 769     pcursor->close();
 770
 771     addrman.Add(vAddr, CNetAddr("0.0.0.0"));
 772     printf("Loaded %i addresses\n", addrman.size());
 773
 774     // Note: old records left; we ran into hangs-on-startup
 775     // bugs for some users who (we think) were running after
 776     // an unclean shutdown.
 777
 778     return true;
 779 }
 780
 781 bool LoadAddresses()
 782 {
 783     return CAddrDB("cr+").LoadAddresses();
 784 }
 785
 786
 787
 788
 789 //
 790 // CWalletDB
 791 //
 792
 793 bool CWalletDB::WriteName(const string& strAddress, const string& strName)
 794 {
 795     nWalletDBUpdated++;
 796     return Write(make_pair(string("name"), strAddress), strName);
 797 }
 798
 799 bool CWalletDB::EraseName(const string& strAddress)
 800 {
 801     // This should only be used for sending addresses, never for receiving addresses,
 802     // receiving addresses must always have an address book entry if they're not change return.
 803     nWalletDBUpdated++;
 804     return Erase(make_pair(string("name"), strAddress));
 805 }
 806
 807 bool CWalletDB::ReadAccount(const string& strAccount, CAccount& account)
 808 {
 809     account.SetNull();
 810     return Read(make_pair(string("acc"), strAccount), account);
 811 }
 812
 813 bool CWalletDB::WriteAccount(const string& strAccount, const CAccount& account)
 814 {
 815     return Write(make_pair(string("acc"), strAccount), account);
 816 }
 817
 818 bool CWalletDB::WriteAccountingEntry(const CAccountingEntry& acentry)
 819 {
 820     return Write(boost::make_tuple(string("acentry"), acentry.strAccount, ++nAccountingEntryNumber), acentry);
 821 }
 822
 823 int64 CWalletDB::GetAccountCreditDebit(const string& strAccount)
 824 {
 825     list<CAccountingEntry> entries;
 826     ListAccountCreditDebit(strAccount, entries);
 827
 828     int64 nCreditDebit = 0;
 829     BOOST_FOREACH (const CAccountingEntry& entry, entries)
 830         nCreditDebit += entry.nCreditDebit;
 831
 832     return nCreditDebit;
 833 }
 834
 835 void CWalletDB::ListAccountCreditDebit(const string& strAccount, list<CAccountingEntry>& entries)
 836 {
 837     bool fAllAccounts = (strAccount == "*");
 838
 839     Dbc* pcursor = GetCursor();
 840     if (!pcursor)
 841         throw runtime_error("CWalletDB::ListAccountCreditDebit() : cannot create DB cursor");
 842     unsigned int fFlags = DB_SET_RANGE;
 843     loop
 844     {
 845         // Read next record
 846         CDataStream ssKey;
 847         if (fFlags == DB_SET_RANGE)
 848             ssKey << boost::make_tuple(string("acentry"), (fAllAccounts? string("") : strAccount), uint64(0));
 849         CDataStream ssValue;
 850         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
 851         fFlags = DB_NEXT;
 852         if (ret == DB_NOTFOUND)
 853             break;
 854         else if (ret != 0)
 855         {
 856             pcursor->close();
 857             throw runtime_error("CWalletDB::ListAccountCreditDebit() : error scanning DB");
 858         }
 859
 860         // Unserialize
 861         string strType;
 862         ssKey >> strType;
 863         if (strType != "acentry")
 864             break;
 865         CAccountingEntry acentry;
 866         ssKey >> acentry.strAccount;
 867         if (!fAllAccounts && acentry.strAccount != strAccount)
 868             break;
 869
 870         ssValue >> acentry;
 871         entries.push_back(acentry);
 872     }
 873
 874     pcursor->close();
 875 }
 876
 877
 878 int CWalletDB::LoadWallet(CWallet* pwallet)
 879 {
 880     pwallet->vchDefaultKey.clear();
 881     int nFileVersion = 0;
 882     vector<uint256> vWalletUpgrade;
 883     bool fIsEncrypted = false;
 884
 885     //// todo: shouldn't we catch exceptions and try to recover and continue?
 886     {
 887         LOCK(pwallet->cs_wallet);
 888         int nMinVersion = 0;
 889         if (Read((string)"minversion", nMinVersion))
 890         {
 891             if (nMinVersion > CLIENT_VERSION)
 892                 return DB_TOO_NEW;
 893             pwallet->LoadMinVersion(nMinVersion);
 894         }
 895
 896         // Get cursor
 897         Dbc* pcursor = GetCursor();
 898         if (!pcursor)
 899         {
 900             printf("Error getting wallet database cursor\n");
 901             return DB_CORRUPT;
 902         }
 903
 904         loop
 905         {
 906             // Read next record
 907             CDataStream ssKey;
 908             CDataStream ssValue;
 909             int ret = ReadAtCursor(pcursor, ssKey, ssValue);
 910             if (ret == DB_NOTFOUND)
 911                 break;
 912             else if (ret != 0)
 913             {
 914                 printf("Error reading next record from wallet database\n");
 915                 return DB_CORRUPT;
 916             }
 917
 918             // Unserialize
 919             // Taking advantage of the fact that pair serialization
 920             // is just the two items serialized one after the other
 921             string strType;
 922             ssKey >> strType;
 923             if (strType == "name")
 924             {
 925                 string strAddress;
 926                 ssKey >> strAddress;
 927                 ssValue >> pwallet->mapAddressBook[strAddress];
 928             }
 929             else if (strType == "tx")
 930             {
 931                 uint256 hash;
 932                 ssKey >> hash;
 933                 CWalletTx& wtx = pwallet->mapWallet[hash];
 934                 ssValue >> wtx;
 935                 wtx.BindWallet(pwallet);
 936
 937                 if (wtx.GetHash() != hash)
 938                     printf("Error in wallet.dat, hash mismatch\n");
 939
 940                 // Undo serialize changes in 31600
 941                 if (31404 <= wtx.fTimeReceivedIsTxTime && wtx.fTimeReceivedIsTxTime <= 31703)
 942                 {
 943                     if (!ssValue.empty())
 944                     {
 945                         char fTmp;
 946                         char fUnused;
 947                         ssValue >> fTmp >> fUnused >> wtx.strFromAccount;
 948                         printf("LoadWallet() upgrading tx ver=%d %d '%s' %s\n", wtx.fTimeReceivedIsTxTime, fTmp, wtx.strFromAccount.c_str(), hash.ToString().c_str());
 949                         wtx.fTimeReceivedIsTxTime = fTmp;
 950                     }
 951                     else
 952                     {
 953                         printf("LoadWallet() repairing tx ver=%d %s\n", wtx.fTimeReceivedIsTxTime, hash.ToString().c_str());
 954                         wtx.fTimeReceivedIsTxTime = 0;
 955                     }
 956                     vWalletUpgrade.push_back(hash);
 957                 }
 958
 959                 //// debug print
 960                 //printf("LoadWallet  %s\n", wtx.GetHash().ToString().c_str());
 961                 //printf(" %12I64d  %s  %s  %s\n",
 962                 //    wtx.vout[0].nValue,
 963                 //    DateTimeStrFormat("%x %H:%M:%S", wtx.GetBlockTime()).c_str(),
 964                 //    wtx.hashBlock.ToString().substr(0,20).c_str(),
 965                 //    wtx.mapValue["message"].c_str());
 966             }
 967             else if (strType == "acentry")
 968             {
 969                 string strAccount;
 970                 ssKey >> strAccount;
 971                 uint64 nNumber;
 972                 ssKey >> nNumber;
 973                 if (nNumber > nAccountingEntryNumber)
 974                     nAccountingEntryNumber = nNumber;
 975             }
 976             else if (strType == "key" || strType == "wkey")
 977             {
 978                 vector<unsigned char> vchPubKey;
 979                 ssKey >> vchPubKey;
 980                 CKey key;
 981                 if (strType == "key")
 982                 {
 983                     CPrivKey pkey;
 984                     ssValue >> pkey;
 985                     key.SetPubKey(vchPubKey);
 986                     key.SetPrivKey(pkey);
 987                     if (key.GetPubKey() != vchPubKey)
 988                     {
 989                         printf("Error reading wallet database: CPrivKey pubkey inconsistency\n");
 990                         return DB_CORRUPT;
 991                     }
 992                     if (!key.IsValid())
 993                     {
 994                         printf("Error reading wallet database: invalid CPrivKey\n");
 995                         return DB_CORRUPT;
 996                     }
 997                 }
 998                 else
 999                 {
1000                     CWalletKey wkey;
1001                     ssValue >> wkey;
1002                     key.SetPubKey(vchPubKey);
1003                     key.SetPrivKey(wkey.vchPrivKey);
1004                     if (key.GetPubKey() != vchPubKey)
1005                     {
1006                         printf("Error reading wallet database: CWalletKey pubkey inconsistency\n");
1007                         return DB_CORRUPT;
1008                     }
1009                     if (!key.IsValid())
1010                     {
1011                         printf("Error reading wallet database: invalid CWalletKey\n");
1012                         return DB_CORRUPT;
1013                     }
1014                 }
1015                 if (!pwallet->LoadKey(key))
1016                 {
1017                     printf("Error reading wallet database: LoadKey failed\n");
1018                     return DB_CORRUPT;
1019                 }
1020             }
1021             else if (strType == "mkey")
1022             {
1023                 unsigned int nID;
1024                 ssKey >> nID;
1025                 CMasterKey kMasterKey;
1026                 ssValue >> kMasterKey;
1027                 if(pwallet->mapMasterKeys.count(nID) != 0)
1028                 {
1029                     printf("Error reading wallet database: duplicate CMasterKey id %u\n", nID);
1030                     return DB_CORRUPT;
1031                 }
1032                 pwallet->mapMasterKeys[nID] = kMasterKey;
1033                 if (pwallet->nMasterKeyMaxID < nID)
1034                     pwallet->nMasterKeyMaxID = nID;
1035             }
1036             else if (strType == "ckey")
1037             {
1038                 vector<unsigned char> vchPubKey;
1039                 ssKey >> vchPubKey;
1040                 vector<unsigned char> vchPrivKey;
1041                 ssValue >> vchPrivKey;
1042                 if (!pwallet->LoadCryptedKey(vchPubKey, vchPrivKey))
1043                 {
1044                     printf("Error reading wallet database: LoadCryptedKey failed\n");
1045                     return DB_CORRUPT;
1046                 }
1047                 fIsEncrypted = true;
1048             }
1049             else if (strType == "defaultkey")
1050             {
1051                 ssValue >> pwallet->vchDefaultKey;
1052             }
1053             else if (strType == "pool")
1054             {
1055                 int64 nIndex;
1056                 ssKey >> nIndex;
1057                 pwallet->setKeyPool.insert(nIndex);
1058             }
1059             else if (strType == "version")
1060             {
1061                 ssValue >> nFileVersion;
1062                 if (nFileVersion == 10300)
1063                     nFileVersion = 300;
1064             }
1065             else if (strType == "cscript")
1066             {
1067                 uint160 hash;
1068                 ssKey >> hash;
1069                 CScript script;
1070                 ssValue >> script;
1071                 if (!pwallet->LoadCScript(script))
1072                 {
1073                     printf("Error reading wallet database: LoadCScript failed\n");
1074                     return DB_CORRUPT;
1075                 }
1076             }
1077         }
1078         pcursor->close();
1079     }
1080
1081     BOOST_FOREACH(uint256 hash, vWalletUpgrade)
1082         WriteTx(hash, pwallet->mapWallet[hash]);
1083
1084     printf("nFileVersion = %d\n", nFileVersion);
1085
1086
1087     // Rewrite encrypted wallets of versions 0.4.0 and 0.5.0rc:
1088     if (fIsEncrypted && (nFileVersion == 40000 || nFileVersion == 50000))
1089         return DB_NEED_REWRITE;
1090
1091     if (nFileVersion < CLIENT_VERSION) // Update
1092     {
1093         // Get rid of old debug.log file in current directory
1094         if (nFileVersion <= 105 && !pszSetDataDir[0])
1095             unlink("debug.log");
1096
1097         WriteVersion(CLIENT_VERSION);
1098     }
1099
1100     return DB_LOAD_OK;
1101 }
1102
1103 void ThreadFlushWalletDB(void* parg)
1104 {
1105     const string& strFile = ((const string*)parg)[0];
1106     static bool fOneThread;
1107     if (fOneThread)
1108         return;
1109     fOneThread = true;
1110     if (!GetBoolArg("-flushwallet", true))
1111         return;
1112
1113     unsigned int nLastSeen = nWalletDBUpdated;
1114     unsigned int nLastFlushed = nWalletDBUpdated;
1115     int64 nLastWalletUpdate = GetTime();
1116     while (!fShutdown)
1117     {
1118         Sleep(500);
1119
1120         if (nLastSeen != nWalletDBUpdated)
1121         {
1122             nLastSeen = nWalletDBUpdated;
1123             nLastWalletUpdate = GetTime();
1124         }
1125
1126         if (nLastFlushed != nWalletDBUpdated && GetTime() - nLastWalletUpdate >= 2)
1127         {
1128             TRY_LOCK(cs_db,lockDb);
1129             if (lockDb)
1130             {
1131                 // Don't do this if any databases are in use
1132                 int nRefCount = 0;
1133                 map<string, int>::iterator mi = mapFileUseCount.begin();
1134                 while (mi != mapFileUseCount.end())
1135                 {
1136                     nRefCount += (*mi).second;
1137                     mi++;
1138                 }
1139
1140                 if (nRefCount == 0 && !fShutdown)
1141                 {
1142                     map<string, int>::iterator mi = mapFileUseCount.find(strFile);
1143                     if (mi != mapFileUseCount.end())
1144                     {
1145                         printf("%s ", DateTimeStrFormat("%x %H:%M:%S", GetTime()).c_str());
1146                         printf("Flushing wallet.dat\n");
1147                         nLastFlushed = nWalletDBUpdated;
1148                         int64 nStart = GetTimeMillis();
1149
1150                         // Flush wallet.dat so it's self contained
1151                         CloseDb(strFile);
1152                         dbenv.txn_checkpoint(0, 0, 0);
1153                         dbenv.lsn_reset(strFile.c_str(), 0);
1154
1155                         mapFileUseCount.erase(mi++);
1156                         printf("Flushed wallet.dat %"PRI64d"ms\n", GetTimeMillis() - nStart);
1157                     }
1158                 }
1159             }
1160         }
1161     }
1162 }
1163
1164 bool BackupWallet(const CWallet& wallet, const string& strDest)
1165 {
1166     if (!wallet.fFileBacked)
1167         return false;
1168     while (!fShutdown)
1169     {
1170         {
1171             LOCK(cs_db);
1172             if (!mapFileUseCount.count(wallet.strWalletFile) || mapFileUseCount[wallet.strWalletFile] == 0)
1173             {
1174                 // Flush log data to the dat file
1175                 CloseDb(wallet.strWalletFile);
1176                 dbenv.txn_checkpoint(0, 0, 0);
1177                 dbenv.lsn_reset(wallet.strWalletFile.c_str(), 0);
1178                 mapFileUseCount.erase(wallet.strWalletFile);
1179
1180                 // Copy wallet.dat
1181                 filesystem::path pathSrc(GetDataDir() + "/" + wallet.strWalletFile);
1182                 pathSrc.make_preferred();
1183                 filesystem::path pathDest(strDest);
1184                 pathDest.make_preferred();
1185                 if (filesystem::is_directory(pathDest))
1186                     pathDest = pathDest / wallet.strWalletFile;
1187
1188                 try {
1189 #if BOOST_VERSION >= 104000
1190                     filesystem::copy_file(pathSrc, pathDest, filesystem::copy_option::overwrite_if_exists);
1191 #else
1192                     filesystem::copy_file(pathSrc, pathDest);
1193 #endif
1194                     printf("copied wallet.dat to %s\n", pathDest.string().c_str());
1195                     return true;
1196                 } catch(const filesystem::filesystem_error &e) {
1197                     printf("error copying wallet.dat to %s - %s\n", pathDest.string().c_str(), e.what());
1198                     return false;
1199                 }
1200             }
1201         }
1202         Sleep(100);
1203     }
1204     return false;
1205 }