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// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2018 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 <addrman.h>
#include <hash.h>
#include <protocol.h>
#include <util/strencodings.h>
#include <wallet/walletutil.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);
}
/**
* @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());
// Wallet file must be a plain filename without a directory
if (walletFile != fs::basename(walletFile) + fs::extension(walletFile))
{
errorStr = strprintf(_("Wallet %s resides outside wallet directory %s"), walletFile, walletDir.string());
return false;
}
if (!env->Open(true /* retry */)) {
errorStr = strprintf(_("Error initializing wallet database environment %s!"), 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."),
walletFile, backup_filename, walletDir);
}
if (r == BerkeleyEnvironment::VerifyResult::RECOVER_FAIL)
{
errorStr = strprintf(_("%s corrupt, salvage failed"), 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;
WriteVersion(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;
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();
}
}