forked from bitcoin/bitcoin
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathdb.cpp
More file actions
920 lines (809 loc) · 32.4 KB
/
db.cpp
File metadata and controls
920 lines (809 loc) · 32.4 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2019 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <wallet/db.h>
#include <util/strencodings.h>
#include <util/translation.h>
#include <stdint.h>
#ifndef WIN32
#include <sys/stat.h>
#endif
#include <boost/thread.hpp>
namespace {
//! Make sure database has a unique fileid within the environment. If it
//! doesn't, throw an error. BDB caches do not work properly when more than one
//! open database has the same fileid (values written to one database may show
//! up in reads to other databases).
//!
//! BerkeleyDB generates unique fileids by default
//! (https://docs.oracle.com/cd/E17275_01/html/programmer_reference/program_copy.html),
//! so bitcoin should never create different databases with the same fileid, but
//! this error can be triggered if users manually copy database files.
void CheckUniqueFileid(const BerkeleyEnvironment& env, const std::string& filename, Db& db, WalletDatabaseFileId& fileid)
{
if (env.IsMock()) return;
int ret = db.get_mpf()->get_fileid(fileid.value);
if (ret != 0) {
throw std::runtime_error(strprintf("BerkeleyBatch: Can't open database %s (get_fileid failed with %d)", filename, ret));
}
for (const auto& item : env.m_fileids) {
if (fileid == item.second && &fileid != &item.second) {
throw std::runtime_error(strprintf("BerkeleyBatch: Can't open database %s (duplicates fileid %s from %s)", filename,
HexStr(std::begin(item.second.value), std::end(item.second.value)), item.first));
}
}
}
CCriticalSection cs_db;
std::map<std::string, std::weak_ptr<BerkeleyEnvironment>> g_dbenvs GUARDED_BY(cs_db); //!< Map from directory name to db environment.
} // namespace
bool WalletDatabaseFileId::operator==(const WalletDatabaseFileId& rhs) const
{
return memcmp(value, &rhs.value, sizeof(value)) == 0;
}
static void SplitWalletPath(const fs::path& wallet_path, fs::path& env_directory, std::string& database_filename)
{
if (fs::is_regular_file(wallet_path)) {
// Special case for backwards compatibility: if wallet path points to an
// existing file, treat it as the path to a BDB data file in a parent
// directory that also contains BDB log files.
env_directory = wallet_path.parent_path();
database_filename = wallet_path.filename().string();
} else {
// Normal case: Interpret wallet path as a directory path containing
// data and log files.
env_directory = wallet_path;
database_filename = "wallet.dat";
}
}
bool IsWalletLoaded(const fs::path& wallet_path)
{
fs::path env_directory;
std::string database_filename;
SplitWalletPath(wallet_path, env_directory, database_filename);
LOCK(cs_db);
auto env = g_dbenvs.find(env_directory.string());
if (env == g_dbenvs.end()) return false;
auto database = env->second.lock();
return database && database->IsDatabaseLoaded(database_filename);
}
fs::path WalletDataFilePath(const fs::path& wallet_path)
{
fs::path env_directory;
std::string database_filename;
SplitWalletPath(wallet_path, env_directory, database_filename);
return env_directory / database_filename;
}
/**
* @param[in] wallet_path Path to wallet directory. Or (for backwards compatibility only) a path to a berkeley btree data file inside a wallet directory.
* @param[out] database_filename Filename of berkeley btree data file inside the wallet directory.
* @return A shared pointer to the BerkeleyEnvironment object for the wallet directory, never empty because ~BerkeleyEnvironment
* erases the weak pointer from the g_dbenvs map.
* @post A new BerkeleyEnvironment weak pointer is inserted into g_dbenvs if the directory path key was not already in the map.
*/
std::shared_ptr<BerkeleyEnvironment> GetWalletEnv(const fs::path& wallet_path, std::string& database_filename)
{
fs::path env_directory;
SplitWalletPath(wallet_path, env_directory, database_filename);
LOCK(cs_db);
auto inserted = g_dbenvs.emplace(env_directory.string(), std::weak_ptr<BerkeleyEnvironment>());
if (inserted.second) {
auto env = std::make_shared<BerkeleyEnvironment>(env_directory.string());
inserted.first->second = env;
return env;
}
return inserted.first->second.lock();
}
//
// BerkeleyBatch
//
void BerkeleyEnvironment::Close()
{
if (!fDbEnvInit)
return;
fDbEnvInit = false;
for (auto& db : m_databases) {
auto count = mapFileUseCount.find(db.first);
assert(count == mapFileUseCount.end() || count->second == 0);
BerkeleyDatabase& database = db.second.get();
if (database.m_db) {
database.m_db->close(0);
database.m_db.reset();
}
}
FILE* error_file = nullptr;
dbenv->get_errfile(&error_file);
int ret = dbenv->close(0);
if (ret != 0)
LogPrintf("BerkeleyEnvironment::Close: Error %d closing database environment: %s\n", ret, DbEnv::strerror(ret));
if (!fMockDb)
DbEnv((u_int32_t)0).remove(strPath.c_str(), 0);
if (error_file) fclose(error_file);
UnlockDirectory(strPath, ".walletlock");
}
void BerkeleyEnvironment::Reset()
{
dbenv.reset(new DbEnv(DB_CXX_NO_EXCEPTIONS));
fDbEnvInit = false;
fMockDb = false;
}
BerkeleyEnvironment::BerkeleyEnvironment(const fs::path& dir_path) : strPath(dir_path.string())
{
Reset();
}
BerkeleyEnvironment::~BerkeleyEnvironment()
{
LOCK(cs_db);
g_dbenvs.erase(strPath);
Close();
}
bool BerkeleyEnvironment::Open(bool retry)
{
if (fDbEnvInit)
return true;
boost::this_thread::interruption_point();
fs::path pathIn = strPath;
TryCreateDirectories(pathIn);
if (!LockDirectory(pathIn, ".walletlock")) {
LogPrintf("Cannot obtain a lock on wallet directory %s. Another instance of bitcoin may be using it.\n", strPath);
return false;
}
fs::path pathLogDir = pathIn / "database";
TryCreateDirectories(pathLogDir);
fs::path pathErrorFile = pathIn / "db.log";
LogPrintf("BerkeleyEnvironment::Open: LogDir=%s ErrorFile=%s\n", pathLogDir.string(), pathErrorFile.string());
unsigned int nEnvFlags = 0;
if (gArgs.GetBoolArg("-privdb", DEFAULT_WALLET_PRIVDB))
nEnvFlags |= DB_PRIVATE;
dbenv->set_lg_dir(pathLogDir.string().c_str());
dbenv->set_cachesize(0, 0x100000, 1); // 1 MiB should be enough for just the wallet
dbenv->set_lg_bsize(0x10000);
dbenv->set_lg_max(1048576);
dbenv->set_lk_max_locks(40000);
dbenv->set_lk_max_objects(40000);
dbenv->set_errfile(fsbridge::fopen(pathErrorFile, "a")); /// debug
dbenv->set_flags(DB_AUTO_COMMIT, 1);
dbenv->set_flags(DB_TXN_WRITE_NOSYNC, 1);
dbenv->log_set_config(DB_LOG_AUTO_REMOVE, 1);
int ret = dbenv->open(strPath.c_str(),
DB_CREATE |
DB_INIT_LOCK |
DB_INIT_LOG |
DB_INIT_MPOOL |
DB_INIT_TXN |
DB_THREAD |
DB_RECOVER |
nEnvFlags,
S_IRUSR | S_IWUSR);
if (ret != 0) {
LogPrintf("BerkeleyEnvironment::Open: Error %d opening database environment: %s\n", ret, DbEnv::strerror(ret));
int ret2 = dbenv->close(0);
if (ret2 != 0) {
LogPrintf("BerkeleyEnvironment::Open: Error %d closing failed database environment: %s\n", ret2, DbEnv::strerror(ret2));
}
Reset();
if (retry) {
// try moving the database env out of the way
fs::path pathDatabaseBak = pathIn / strprintf("database.%d.bak", GetTime());
try {
fs::rename(pathLogDir, pathDatabaseBak);
LogPrintf("Moved old %s to %s. Retrying.\n", pathLogDir.string(), pathDatabaseBak.string());
} catch (const fs::filesystem_error&) {
// failure is ok (well, not really, but it's not worse than what we started with)
}
// try opening it again one more time
if (!Open(false /* retry */)) {
// if it still fails, it probably means we can't even create the database env
return false;
}
} else {
return false;
}
}
fDbEnvInit = true;
fMockDb = false;
return true;
}
//! Construct an in-memory mock Berkeley environment for testing and as a place-holder for g_dbenvs emplace
BerkeleyEnvironment::BerkeleyEnvironment()
{
Reset();
boost::this_thread::interruption_point();
LogPrint(BCLog::DB, "BerkeleyEnvironment::MakeMock\n");
dbenv->set_cachesize(1, 0, 1);
dbenv->set_lg_bsize(10485760 * 4);
dbenv->set_lg_max(10485760);
dbenv->set_lk_max_locks(10000);
dbenv->set_lk_max_objects(10000);
dbenv->set_flags(DB_AUTO_COMMIT, 1);
dbenv->log_set_config(DB_LOG_IN_MEMORY, 1);
int ret = dbenv->open(nullptr,
DB_CREATE |
DB_INIT_LOCK |
DB_INIT_LOG |
DB_INIT_MPOOL |
DB_INIT_TXN |
DB_THREAD |
DB_PRIVATE,
S_IRUSR | S_IWUSR);
if (ret > 0)
throw std::runtime_error(strprintf("BerkeleyEnvironment::MakeMock: Error %d opening database environment.", ret));
fDbEnvInit = true;
fMockDb = true;
}
BerkeleyEnvironment::VerifyResult BerkeleyEnvironment::Verify(const std::string& strFile, recoverFunc_type recoverFunc, std::string& out_backup_filename)
{
LOCK(cs_db);
assert(mapFileUseCount.count(strFile) == 0);
Db db(dbenv.get(), 0);
int result = db.verify(strFile.c_str(), nullptr, nullptr, 0);
if (result == 0)
return VerifyResult::VERIFY_OK;
else if (recoverFunc == nullptr)
return VerifyResult::RECOVER_FAIL;
// Try to recover:
bool fRecovered = (*recoverFunc)(fs::path(strPath) / strFile, out_backup_filename);
return (fRecovered ? VerifyResult::RECOVER_OK : VerifyResult::RECOVER_FAIL);
}
BerkeleyBatch::SafeDbt::SafeDbt()
{
m_dbt.set_flags(DB_DBT_MALLOC);
}
BerkeleyBatch::SafeDbt::SafeDbt(void* data, size_t size)
: m_dbt(data, size)
{
}
BerkeleyBatch::SafeDbt::~SafeDbt()
{
if (m_dbt.get_data() != nullptr) {
// Clear memory, e.g. in case it was a private key
memory_cleanse(m_dbt.get_data(), m_dbt.get_size());
// under DB_DBT_MALLOC, data is malloced by the Dbt, but must be
// freed by the caller.
// https://docs.oracle.com/cd/E17275_01/html/api_reference/C/dbt.html
if (m_dbt.get_flags() & DB_DBT_MALLOC) {
free(m_dbt.get_data());
}
}
}
const void* BerkeleyBatch::SafeDbt::get_data() const
{
return m_dbt.get_data();
}
u_int32_t BerkeleyBatch::SafeDbt::get_size() const
{
return m_dbt.get_size();
}
BerkeleyBatch::SafeDbt::operator Dbt*()
{
return &m_dbt;
}
bool BerkeleyBatch::Recover(const fs::path& file_path, void *callbackDataIn, bool (*recoverKVcallback)(void* callbackData, CDataStream ssKey, CDataStream ssValue), std::string& newFilename)
{
std::string filename;
std::shared_ptr<BerkeleyEnvironment> env = GetWalletEnv(file_path, filename);
// Recovery procedure:
// move wallet file to walletfilename.timestamp.bak
// Call Salvage with fAggressive=true to
// get as much data as possible.
// Rewrite salvaged data to fresh wallet file
// Set -rescan so any missing transactions will be
// found.
int64_t now = GetTime();
newFilename = strprintf("%s.%d.bak", filename, now);
int result = env->dbenv->dbrename(nullptr, filename.c_str(), nullptr,
newFilename.c_str(), DB_AUTO_COMMIT);
if (result == 0)
LogPrintf("Renamed %s to %s\n", filename, newFilename);
else
{
LogPrintf("Failed to rename %s to %s\n", filename, newFilename);
return false;
}
std::vector<BerkeleyEnvironment::KeyValPair> salvagedData;
bool fSuccess = env->Salvage(newFilename, true, salvagedData);
if (salvagedData.empty())
{
LogPrintf("Salvage(aggressive) found no records in %s.\n", newFilename);
return false;
}
LogPrintf("Salvage(aggressive) found %u records\n", salvagedData.size());
std::unique_ptr<Db> pdbCopy = MakeUnique<Db>(env->dbenv.get(), 0);
int ret = pdbCopy->open(nullptr, // Txn pointer
filename.c_str(), // Filename
"main", // Logical db name
DB_BTREE, // Database type
DB_CREATE, // Flags
0);
if (ret > 0) {
LogPrintf("Cannot create database file %s\n", filename);
pdbCopy->close(0);
return false;
}
DbTxn* ptxn = env->TxnBegin();
for (BerkeleyEnvironment::KeyValPair& row : salvagedData)
{
if (recoverKVcallback)
{
CDataStream ssKey(row.first, SER_DISK, CLIENT_VERSION);
CDataStream ssValue(row.second, SER_DISK, CLIENT_VERSION);
if (!(*recoverKVcallback)(callbackDataIn, ssKey, ssValue))
continue;
}
Dbt datKey(&row.first[0], row.first.size());
Dbt datValue(&row.second[0], row.second.size());
int ret2 = pdbCopy->put(ptxn, &datKey, &datValue, DB_NOOVERWRITE);
if (ret2 > 0)
fSuccess = false;
}
ptxn->commit(0);
pdbCopy->close(0);
return fSuccess;
}
bool BerkeleyBatch::VerifyEnvironment(const fs::path& file_path, std::string& errorStr)
{
std::string walletFile;
std::shared_ptr<BerkeleyEnvironment> env = GetWalletEnv(file_path, walletFile);
fs::path walletDir = env->Directory();
LogPrintf("Using BerkeleyDB version %s\n", DbEnv::version(nullptr, nullptr, nullptr));
LogPrintf("Using wallet %s\n", file_path.string());
if (!env->Open(true /* retry */)) {
errorStr = strprintf(_("Error initializing wallet database environment %s!").translated, walletDir);
return false;
}
return true;
}
bool BerkeleyBatch::VerifyDatabaseFile(const fs::path& file_path, std::string& warningStr, std::string& errorStr, BerkeleyEnvironment::recoverFunc_type recoverFunc)
{
std::string walletFile;
std::shared_ptr<BerkeleyEnvironment> env = GetWalletEnv(file_path, walletFile);
fs::path walletDir = env->Directory();
if (fs::exists(walletDir / walletFile))
{
std::string backup_filename;
BerkeleyEnvironment::VerifyResult r = env->Verify(walletFile, recoverFunc, backup_filename);
if (r == BerkeleyEnvironment::VerifyResult::RECOVER_OK)
{
warningStr = strprintf(_("Warning: Wallet file corrupt, data salvaged!"
" Original %s saved as %s in %s; if"
" your balance or transactions are incorrect you should"
" restore from a backup.").translated,
walletFile, backup_filename, walletDir);
}
if (r == BerkeleyEnvironment::VerifyResult::RECOVER_FAIL)
{
errorStr = strprintf(_("%s corrupt, salvage failed").translated, walletFile);
return false;
}
}
// also return true if files does not exists
return true;
}
/* End of headers, beginning of key/value data */
static const char *HEADER_END = "HEADER=END";
/* End of key/value data */
static const char *DATA_END = "DATA=END";
bool BerkeleyEnvironment::Salvage(const std::string& strFile, bool fAggressive, std::vector<BerkeleyEnvironment::KeyValPair>& vResult)
{
LOCK(cs_db);
assert(mapFileUseCount.count(strFile) == 0);
u_int32_t flags = DB_SALVAGE;
if (fAggressive)
flags |= DB_AGGRESSIVE;
std::stringstream strDump;
Db db(dbenv.get(), 0);
int result = db.verify(strFile.c_str(), nullptr, &strDump, flags);
if (result == DB_VERIFY_BAD) {
LogPrintf("BerkeleyEnvironment::Salvage: Database salvage found errors, all data may not be recoverable.\n");
if (!fAggressive) {
LogPrintf("BerkeleyEnvironment::Salvage: Rerun with aggressive mode to ignore errors and continue.\n");
return false;
}
}
if (result != 0 && result != DB_VERIFY_BAD) {
LogPrintf("BerkeleyEnvironment::Salvage: Database salvage failed with result %d.\n", result);
return false;
}
// Format of bdb dump is ascii lines:
// header lines...
// HEADER=END
// hexadecimal key
// hexadecimal value
// ... repeated
// DATA=END
std::string strLine;
while (!strDump.eof() && strLine != HEADER_END)
getline(strDump, strLine); // Skip past header
std::string keyHex, valueHex;
while (!strDump.eof() && keyHex != DATA_END) {
getline(strDump, keyHex);
if (keyHex != DATA_END) {
if (strDump.eof())
break;
getline(strDump, valueHex);
if (valueHex == DATA_END) {
LogPrintf("BerkeleyEnvironment::Salvage: WARNING: Number of keys in data does not match number of values.\n");
break;
}
vResult.push_back(make_pair(ParseHex(keyHex), ParseHex(valueHex)));
}
}
if (keyHex != DATA_END) {
LogPrintf("BerkeleyEnvironment::Salvage: WARNING: Unexpected end of file while reading salvage output.\n");
return false;
}
return (result == 0);
}
void BerkeleyEnvironment::CheckpointLSN(const std::string& strFile)
{
dbenv->txn_checkpoint(0, 0, 0);
if (fMockDb)
return;
dbenv->lsn_reset(strFile.c_str(), 0);
}
BerkeleyBatch::BerkeleyBatch(BerkeleyDatabase& database, const char* pszMode, bool fFlushOnCloseIn) : pdb(nullptr), activeTxn(nullptr)
{
fReadOnly = (!strchr(pszMode, '+') && !strchr(pszMode, 'w'));
fFlushOnClose = fFlushOnCloseIn;
env = database.env.get();
if (database.IsDummy()) {
return;
}
const std::string &strFilename = database.strFile;
bool fCreate = strchr(pszMode, 'c') != nullptr;
unsigned int nFlags = DB_THREAD;
if (fCreate)
nFlags |= DB_CREATE;
{
LOCK(cs_db);
if (!env->Open(false /* retry */))
throw std::runtime_error("BerkeleyBatch: Failed to open database environment.");
pdb = database.m_db.get();
if (pdb == nullptr) {
int ret;
std::unique_ptr<Db> pdb_temp = MakeUnique<Db>(env->dbenv.get(), 0);
bool fMockDb = env->IsMock();
if (fMockDb) {
DbMpoolFile* mpf = pdb_temp->get_mpf();
ret = mpf->set_flags(DB_MPOOL_NOFILE, 1);
if (ret != 0) {
throw std::runtime_error(strprintf("BerkeleyBatch: Failed to configure for no temp file backing for database %s", strFilename));
}
}
ret = pdb_temp->open(nullptr, // Txn pointer
fMockDb ? nullptr : strFilename.c_str(), // Filename
fMockDb ? strFilename.c_str() : "main", // Logical db name
DB_BTREE, // Database type
nFlags, // Flags
0);
if (ret != 0) {
throw std::runtime_error(strprintf("BerkeleyBatch: Error %d, can't open database %s", ret, strFilename));
}
// Call CheckUniqueFileid on the containing BDB environment to
// avoid BDB data consistency bugs that happen when different data
// files in the same environment have the same fileid.
//
// Also call CheckUniqueFileid on all the other g_dbenvs to prevent
// bitcoin from opening the same data file through another
// environment when the file is referenced through equivalent but
// not obviously identical symlinked or hard linked or bind mounted
// paths. In the future a more relaxed check for equal inode and
// device ids could be done instead, which would allow opening
// different backup copies of a wallet at the same time. Maybe even
// more ideally, an exclusive lock for accessing the database could
// be implemented, so no equality checks are needed at all. (Newer
// versions of BDB have an set_lk_exclusive method for this
// purpose, but the older version we use does not.)
for (const auto& env : g_dbenvs) {
CheckUniqueFileid(*env.second.lock().get(), strFilename, *pdb_temp, this->env->m_fileids[strFilename]);
}
pdb = pdb_temp.release();
database.m_db.reset(pdb);
if (fCreate && !Exists(std::string("version"))) {
bool fTmp = fReadOnly;
fReadOnly = false;
Write(std::string("version"), CLIENT_VERSION);
fReadOnly = fTmp;
}
}
++env->mapFileUseCount[strFilename];
strFile = strFilename;
}
}
void BerkeleyBatch::Flush()
{
if (activeTxn)
return;
// Flush database activity from memory pool to disk log
unsigned int nMinutes = 0;
if (fReadOnly)
nMinutes = 1;
if (env) { // env is nullptr for dummy databases (i.e. in tests). Don't actually flush if env is nullptr so we don't segfault
env->dbenv->txn_checkpoint(nMinutes ? gArgs.GetArg("-dblogsize", DEFAULT_WALLET_DBLOGSIZE) * 1024 : 0, nMinutes, 0);
}
}
void BerkeleyDatabase::IncrementUpdateCounter()
{
++nUpdateCounter;
}
void BerkeleyBatch::Close()
{
if (!pdb)
return;
if (activeTxn)
activeTxn->abort();
activeTxn = nullptr;
pdb = nullptr;
if (fFlushOnClose)
Flush();
{
LOCK(cs_db);
--env->mapFileUseCount[strFile];
}
env->m_db_in_use.notify_all();
}
void BerkeleyEnvironment::CloseDb(const std::string& strFile)
{
{
LOCK(cs_db);
auto it = m_databases.find(strFile);
assert(it != m_databases.end());
BerkeleyDatabase& database = it->second.get();
if (database.m_db) {
// Close the database handle
database.m_db->close(0);
database.m_db.reset();
}
}
}
void BerkeleyEnvironment::ReloadDbEnv()
{
// Make sure that no Db's are in use
AssertLockNotHeld(cs_db);
std::unique_lock<CCriticalSection> lock(cs_db);
m_db_in_use.wait(lock, [this](){
for (auto& count : mapFileUseCount) {
if (count.second > 0) return false;
}
return true;
});
std::vector<std::string> filenames;
for (auto it : m_databases) {
filenames.push_back(it.first);
}
// Close the individual Db's
for (const std::string& filename : filenames) {
CloseDb(filename);
}
// Reset the environment
Flush(true); // This will flush and close the environment
Reset();
Open(true);
}
bool BerkeleyBatch::Rewrite(BerkeleyDatabase& database, const char* pszSkip)
{
if (database.IsDummy()) {
return true;
}
BerkeleyEnvironment *env = database.env.get();
const std::string& strFile = database.strFile;
while (true) {
{
LOCK(cs_db);
if (!env->mapFileUseCount.count(strFile) || env->mapFileUseCount[strFile] == 0) {
// Flush log data to the dat file
env->CloseDb(strFile);
env->CheckpointLSN(strFile);
env->mapFileUseCount.erase(strFile);
bool fSuccess = true;
LogPrintf("BerkeleyBatch::Rewrite: Rewriting %s...\n", strFile);
std::string strFileRes = strFile + ".rewrite";
{ // surround usage of db with extra {}
BerkeleyBatch db(database, "r");
std::unique_ptr<Db> pdbCopy = MakeUnique<Db>(env->dbenv.get(), 0);
int ret = pdbCopy->open(nullptr, // Txn pointer
strFileRes.c_str(), // Filename
"main", // Logical db name
DB_BTREE, // Database type
DB_CREATE, // Flags
0);
if (ret > 0) {
LogPrintf("BerkeleyBatch::Rewrite: Can't create database file %s\n", strFileRes);
fSuccess = false;
}
Dbc* pcursor = db.GetCursor();
if (pcursor)
while (fSuccess) {
CDataStream ssKey(SER_DISK, CLIENT_VERSION);
CDataStream ssValue(SER_DISK, CLIENT_VERSION);
int ret1 = db.ReadAtCursor(pcursor, ssKey, ssValue);
if (ret1 == DB_NOTFOUND) {
pcursor->close();
break;
} else if (ret1 != 0) {
pcursor->close();
fSuccess = false;
break;
}
if (pszSkip &&
strncmp(ssKey.data(), pszSkip, std::min(ssKey.size(), strlen(pszSkip))) == 0)
continue;
if (strncmp(ssKey.data(), "\x07version", 8) == 0) {
// Update version:
ssValue.clear();
ssValue << CLIENT_VERSION;
}
Dbt datKey(ssKey.data(), ssKey.size());
Dbt datValue(ssValue.data(), ssValue.size());
int ret2 = pdbCopy->put(nullptr, &datKey, &datValue, DB_NOOVERWRITE);
if (ret2 > 0)
fSuccess = false;
}
if (fSuccess) {
db.Close();
env->CloseDb(strFile);
if (pdbCopy->close(0))
fSuccess = false;
} else {
pdbCopy->close(0);
}
}
if (fSuccess) {
Db dbA(env->dbenv.get(), 0);
if (dbA.remove(strFile.c_str(), nullptr, 0))
fSuccess = false;
Db dbB(env->dbenv.get(), 0);
if (dbB.rename(strFileRes.c_str(), nullptr, strFile.c_str(), 0))
fSuccess = false;
}
if (!fSuccess)
LogPrintf("BerkeleyBatch::Rewrite: Failed to rewrite database file %s\n", strFileRes);
return fSuccess;
}
}
MilliSleep(100);
}
}
void BerkeleyEnvironment::Flush(bool fShutdown)
{
int64_t nStart = GetTimeMillis();
// Flush log data to the actual data file on all files that are not in use
LogPrint(BCLog::DB, "BerkeleyEnvironment::Flush: [%s] Flush(%s)%s\n", strPath, fShutdown ? "true" : "false", fDbEnvInit ? "" : " database not started");
if (!fDbEnvInit)
return;
{
LOCK(cs_db);
std::map<std::string, int>::iterator mi = mapFileUseCount.begin();
while (mi != mapFileUseCount.end()) {
std::string strFile = (*mi).first;
int nRefCount = (*mi).second;
LogPrint(BCLog::DB, "BerkeleyEnvironment::Flush: Flushing %s (refcount = %d)...\n", strFile, nRefCount);
if (nRefCount == 0) {
// Move log data to the dat file
CloseDb(strFile);
LogPrint(BCLog::DB, "BerkeleyEnvironment::Flush: %s checkpoint\n", strFile);
dbenv->txn_checkpoint(0, 0, 0);
LogPrint(BCLog::DB, "BerkeleyEnvironment::Flush: %s detach\n", strFile);
if (!fMockDb)
dbenv->lsn_reset(strFile.c_str(), 0);
LogPrint(BCLog::DB, "BerkeleyEnvironment::Flush: %s closed\n", strFile);
mapFileUseCount.erase(mi++);
} else
mi++;
}
LogPrint(BCLog::DB, "BerkeleyEnvironment::Flush: Flush(%s)%s took %15dms\n", fShutdown ? "true" : "false", fDbEnvInit ? "" : " database not started", GetTimeMillis() - nStart);
if (fShutdown) {
char** listp;
if (mapFileUseCount.empty()) {
dbenv->log_archive(&listp, DB_ARCH_REMOVE);
Close();
if (!fMockDb) {
fs::remove_all(fs::path(strPath) / "database");
}
}
}
}
}
bool BerkeleyBatch::PeriodicFlush(BerkeleyDatabase& database)
{
if (database.IsDummy()) {
return true;
}
bool ret = false;
BerkeleyEnvironment *env = database.env.get();
const std::string& strFile = database.strFile;
TRY_LOCK(cs_db, lockDb);
if (lockDb)
{
// Don't do this if any databases are in use
int nRefCount = 0;
std::map<std::string, int>::iterator mit = env->mapFileUseCount.begin();
while (mit != env->mapFileUseCount.end())
{
nRefCount += (*mit).second;
mit++;
}
if (nRefCount == 0)
{
boost::this_thread::interruption_point();
std::map<std::string, int>::iterator mi = env->mapFileUseCount.find(strFile);
if (mi != env->mapFileUseCount.end())
{
LogPrint(BCLog::DB, "Flushing %s\n", strFile);
int64_t nStart = GetTimeMillis();
// Flush wallet file so it's self contained
env->CloseDb(strFile);
env->CheckpointLSN(strFile);
env->mapFileUseCount.erase(mi++);
LogPrint(BCLog::DB, "Flushed %s %dms\n", strFile, GetTimeMillis() - nStart);
ret = true;
}
}
}
return ret;
}
bool BerkeleyDatabase::Rewrite(const char* pszSkip)
{
return BerkeleyBatch::Rewrite(*this, pszSkip);
}
bool BerkeleyDatabase::Backup(const std::string& strDest)
{
if (IsDummy()) {
return false;
}
while (true)
{
{
LOCK(cs_db);
if (!env->mapFileUseCount.count(strFile) || env->mapFileUseCount[strFile] == 0)
{
// Flush log data to the dat file
env->CloseDb(strFile);
env->CheckpointLSN(strFile);
env->mapFileUseCount.erase(strFile);
// Copy wallet file
fs::path pathSrc = env->Directory() / strFile;
fs::path pathDest(strDest);
if (fs::is_directory(pathDest))
pathDest /= strFile;
try {
if (fs::equivalent(pathSrc, pathDest)) {
LogPrintf("cannot backup to wallet source file %s\n", pathDest.string());
return false;
}
fs::copy_file(pathSrc, pathDest, fs::copy_option::overwrite_if_exists);
LogPrintf("copied %s to %s\n", strFile, pathDest.string());
return true;
} catch (const fs::filesystem_error& e) {
LogPrintf("error copying %s to %s - %s\n", strFile, pathDest.string(), fsbridge::get_filesystem_error_message(e));
return false;
}
}
}
MilliSleep(100);
}
}
void BerkeleyDatabase::Flush(bool shutdown)
{
if (!IsDummy()) {
env->Flush(shutdown);
if (shutdown) {
LOCK(cs_db);
g_dbenvs.erase(env->Directory().string());
env = nullptr;
} else {
// TODO: To avoid g_dbenvs.erase erasing the environment prematurely after the
// first database shutdown when multiple databases are open in the same
// environment, should replace raw database `env` pointers with shared or weak
// pointers, or else separate the database and environment shutdowns so
// environments can be shut down after databases.
env->m_fileids.erase(strFile);
}
}
}
void BerkeleyDatabase::ReloadDbEnv()
{
if (!IsDummy()) {
env->ReloadDbEnv();
}
}