diff options
Diffstat (limited to 'src/wallet/bdb.cpp')
-rw-r--r-- | src/wallet/bdb.cpp | 869 |
1 files changed, 869 insertions, 0 deletions
diff --git a/src/wallet/bdb.cpp b/src/wallet/bdb.cpp new file mode 100644 index 0000000000..125bf004e4 --- /dev/null +++ b/src/wallet/bdb.cpp @@ -0,0 +1,869 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Copyright (c) 2009-2020 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/bdb.h> +#include <wallet/db.h> + +#include <util/strencodings.h> +#include <util/translation.h> + +#include <stdint.h> + +#ifndef WIN32 +#include <sys/stat.h> +#endif + +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)); + } + } +} + +RecursiveMutex 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; +} + +bool IsBDBWalletLoaded(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; + } + + 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 +BerkeleyEnvironment::BerkeleyEnvironment() +{ + Reset(); + + LogPrint(BCLog::WALLETDB, "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; +} + +bool BerkeleyEnvironment::Verify(const std::string& strFile) +{ + LOCK(cs_db); + assert(mapFileUseCount.count(strFile) == 0); + + Db db(dbenv.get(), 0); + int result = db.verify(strFile.c_str(), nullptr, nullptr, 0); + return result == 0; +} + +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::VerifyEnvironment(const fs::path& file_path, bilingual_str& errorStr) +{ + std::string walletFile; + std::shared_ptr<BerkeleyEnvironment> env = GetWalletEnv(file_path, walletFile); + fs::path walletDir = env->Directory(); + + LogPrintf("Using BerkeleyDB version %s\n", BerkeleyDatabaseVersion()); + LogPrintf("Using wallet %s\n", file_path.string()); + + 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, bilingual_str& errorStr) +{ + std::string walletFile; + std::shared_ptr<BerkeleyEnvironment> env = GetWalletEnv(file_path, walletFile); + fs::path walletDir = env->Directory(); + + if (fs::exists(walletDir / walletFile)) + { + if (!env->Verify(walletFile)) { + errorStr = strprintf(_("%s corrupt. Try using the wallet tool bitcoin-wallet to salvage or restoring a backup."), walletFile); + return false; + } + } + // also return true if files does not exists + return true; +} + +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<RecursiveMutex> 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; + } + } + UninterruptibleSleep(std::chrono::milliseconds{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::WALLETDB, "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::WALLETDB, "BerkeleyEnvironment::Flush: Flushing %s (refcount = %d)...\n", strFile, nRefCount); + if (nRefCount == 0) { + // Move log data to the dat file + CloseDb(strFile); + LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: %s checkpoint\n", strFile); + dbenv->txn_checkpoint(0, 0, 0); + LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: %s detach\n", strFile); + if (!fMockDb) + dbenv->lsn_reset(strFile.c_str(), 0); + LogPrint(BCLog::WALLETDB, "BerkeleyEnvironment::Flush: %s closed\n", strFile); + mapFileUseCount.erase(mi++); + } else + mi++; + } + LogPrint(BCLog::WALLETDB, "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) + { + std::map<std::string, int>::iterator mi = env->mapFileUseCount.find(strFile); + if (mi != env->mapFileUseCount.end()) + { + LogPrint(BCLog::WALLETDB, "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::WALLETDB, "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) const +{ + 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; + } + } + } + UninterruptibleSleep(std::chrono::milliseconds{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(); + } +} + +Dbc* BerkeleyBatch::GetCursor() +{ + if (!pdb) + return nullptr; + Dbc* pcursor = nullptr; + int ret = pdb->cursor(nullptr, &pcursor, 0); + if (ret != 0) + return nullptr; + return pcursor; +} + +int BerkeleyBatch::ReadAtCursor(Dbc* pcursor, CDataStream& ssKey, CDataStream& ssValue) +{ + // Read at cursor + SafeDbt datKey; + SafeDbt datValue; + int ret = pcursor->get(datKey, datValue, DB_NEXT); + if (ret != 0) + return ret; + else if (datKey.get_data() == nullptr || datValue.get_data() == nullptr) + return 99999; + + // Convert to streams + ssKey.SetType(SER_DISK); + ssKey.clear(); + ssKey.write((char*)datKey.get_data(), datKey.get_size()); + ssValue.SetType(SER_DISK); + ssValue.clear(); + ssValue.write((char*)datValue.get_data(), datValue.get_size()); + return 0; +} + +bool BerkeleyBatch::TxnBegin() +{ + if (!pdb || activeTxn) + return false; + DbTxn* ptxn = env->TxnBegin(); + if (!ptxn) + return false; + activeTxn = ptxn; + return true; +} + +bool BerkeleyBatch::TxnCommit() +{ + if (!pdb || !activeTxn) + return false; + int ret = activeTxn->commit(0); + activeTxn = nullptr; + return (ret == 0); +} + +bool BerkeleyBatch::TxnAbort() +{ + if (!pdb || !activeTxn) + return false; + int ret = activeTxn->abort(); + activeTxn = nullptr; + return (ret == 0); +} + +std::string BerkeleyDatabaseVersion() +{ + return DbEnv::version(nullptr, nullptr, nullptr); +} + +bool BerkeleyBatch::ReadKey(CDataStream& key, CDataStream& value) +{ + if (!pdb) + return false; + + // Key + SafeDbt datKey(key.data(), key.size()); + + // Read + SafeDbt datValue; + int ret = pdb->get(activeTxn, datKey, datValue, 0); + if (ret == 0 && datValue.get_data() != nullptr) { + value.write((char*)datValue.get_data(), datValue.get_size()); + return true; + } + return false; +} + +bool BerkeleyBatch::WriteKey(CDataStream& key, CDataStream& value, bool overwrite) +{ + if (!pdb) + return true; + if (fReadOnly) + assert(!"Write called on database in read-only mode"); + + // Key + SafeDbt datKey(key.data(), key.size()); + + // Value + SafeDbt datValue(value.data(), value.size()); + + // Write + int ret = pdb->put(activeTxn, datKey, datValue, (overwrite ? 0 : DB_NOOVERWRITE)); + return (ret == 0); +} + +bool BerkeleyBatch::EraseKey(CDataStream& key) +{ + if (!pdb) + return false; + if (fReadOnly) + assert(!"Erase called on database in read-only mode"); + + // Key + SafeDbt datKey(key.data(), key.size()); + + // Erase + int ret = pdb->del(activeTxn, datKey, 0); + return (ret == 0 || ret == DB_NOTFOUND); +} + +bool BerkeleyBatch::HasKey(CDataStream& key) +{ + if (!pdb) + return false; + + // Key + SafeDbt datKey(key.data(), key.size()); + + // Exists + int ret = pdb->exists(activeTxn, datKey, 0); + return ret == 0; +} |