diff --git a/src/wallet/bdb.h b/src/wallet/bdb.h index edab0839b..8302416c7 100644 --- a/src/wallet/bdb.h +++ b/src/wallet/bdb.h @@ -1,257 +1,255 @@ // 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. #ifndef BITCOIN_WALLET_BDB_H #define BITCOIN_WALLET_BDB_H #include #include #include #include #include #include #include #include #include #include #include #include #include struct bilingual_str; static const unsigned int DEFAULT_WALLET_DBLOGSIZE = 100; static const bool DEFAULT_WALLET_PRIVDB = true; struct WalletDatabaseFileId { u_int8_t value[DB_FILE_ID_LEN]; bool operator==(const WalletDatabaseFileId &rhs) const; }; class BerkeleyDatabase; class BerkeleyEnvironment { private: bool fDbEnvInit; bool fMockDb; // Don't change into fs::path, as that can result in // shutdown problems/crashes caused by a static initialized internal // pointer. std::string strPath; public: std::unique_ptr dbenv; std::map> m_databases; std::unordered_map m_fileids; std::condition_variable_any m_db_in_use; BerkeleyEnvironment(const fs::path &env_directory); BerkeleyEnvironment(); ~BerkeleyEnvironment(); void Reset(); void MakeMock(); bool IsMock() const { return fMockDb; } bool IsInitialized() const { return fDbEnvInit; } bool IsDatabaseLoaded(const std::string &db_filename) const { return m_databases.find(db_filename) != m_databases.end(); } fs::path Directory() const { return strPath; } bool Open(bilingual_str &error); void Close(); void Flush(bool fShutdown); void CheckpointLSN(const std::string &strFile); void CloseDb(const std::string &strFile); void ReloadDbEnv(); DbTxn *TxnBegin(int flags = DB_TXN_WRITE_NOSYNC) { DbTxn *ptxn = nullptr; int ret = dbenv->txn_begin(nullptr, &ptxn, flags); if (!ptxn || ret != 0) { return nullptr; } return ptxn; } }; /** Get BerkeleyEnvironment and database filename given a wallet path. */ std::shared_ptr GetWalletEnv(const fs::path &wallet_path, std::string &database_filename); /** Return whether a BDB wallet database is currently loaded. */ bool IsBDBWalletLoaded(const fs::path &wallet_path); class BerkeleyBatch; /** * An instance of this class represents one database. * For BerkeleyDB this is just a (env, strFile) tuple. */ class BerkeleyDatabase : public WalletDatabase { - friend class BerkeleyBatch; - public: /** Create dummy DB handle */ BerkeleyDatabase() : WalletDatabase(), env(nullptr) {} /** Create DB handle to real database */ BerkeleyDatabase(std::shared_ptr envIn, std::string filename) : WalletDatabase(), env(std::move(envIn)), strFile(std::move(filename)) { auto inserted = this->env->m_databases.emplace(strFile, std::ref(*this)); assert(inserted.second); } ~BerkeleyDatabase() override; /** * Open the database if it is not already opened. * Dummy function, doesn't do anything right now, but is needed for class * abstraction */ void Open(const char *mode) override; /** * Rewrite the entire database on disk, with the exception of key pszSkip if * non-zero */ bool Rewrite(const char *pszSkip = nullptr) override; /** Indicate the a new database user has began using the database. */ void AddRef() override; /** * Indicate that database user has stopped using the database and that it * could be flushed or closed. */ void RemoveRef() override; /** * Back up the entire database to a file. */ bool Backup(const std::string &strDest) const override; /** * Make sure all changes are flushed to database file. */ void Flush() override; /** * Flush to the database file and close the database. * Also close the environment if no other databases are open in it. */ void Close() override; /** * flush the wallet passively (TRY_LOCK) * ideal to be called periodically */ bool PeriodicFlush() override; void IncrementUpdateCounter() override; void ReloadDbEnv() override; /** Verifies the environment and database file */ bool Verify(bilingual_str &error) override; /** * Pointer to shared database environment. * * Normally there is only one BerkeleyDatabase object per * BerkeleyEnvivonment, but in the special, backwards compatible case where * multiple wallet BDB data files are loaded from the same directory, this * will point to a shared instance that gets freed when the last data file * is closed. */ std::shared_ptr env; /** * Database pointer. This is initialized lazily and reset during flushes, * so it can be null. */ std::unique_ptr m_db; + std::string strFile; + /** Make a BerkeleyBatch connected to this database */ std::unique_ptr MakeBatch(const char *mode = "r+", bool flush_on_close = true) override; private: - std::string strFile; - /** * Return whether this database handle is a dummy for testing. * Only to be used at a low level, application should ideally not care * about this. */ bool IsDummy() const { return env == nullptr; } }; /** RAII class that provides access to a Berkeley database */ class BerkeleyBatch : public DatabaseBatch { /** RAII class that automatically cleanses its data on destruction */ class SafeDbt final { Dbt m_dbt; public: // construct Dbt with internally-managed data SafeDbt(); // construct Dbt with provided data SafeDbt(void *data, size_t size); ~SafeDbt(); // delegate to Dbt const void *get_data() const; u_int32_t get_size() const; // conversion operator to access the underlying Dbt operator Dbt *(); }; private: bool ReadKey(CDataStream &&key, CDataStream &value) override; bool WriteKey(CDataStream &&key, CDataStream &&value, bool overwrite = true) override; bool EraseKey(CDataStream &&key) override; bool HasKey(CDataStream &&key) override; protected: Db *pdb; std::string strFile; DbTxn *activeTxn; Dbc *m_cursor; bool fReadOnly; bool fFlushOnClose; BerkeleyEnvironment *env; BerkeleyDatabase &m_database; public: explicit BerkeleyBatch(BerkeleyDatabase &database, const char *pszMode = "r+", bool fFlushOnCloseIn = true); ~BerkeleyBatch() override; BerkeleyBatch(const BerkeleyBatch &) = delete; BerkeleyBatch &operator=(const BerkeleyBatch &) = delete; void Flush() override; void Close() override; bool StartCursor() override; bool ReadAtCursor(CDataStream &ssKey, CDataStream &ssValue, bool &complete) override; void CloseCursor() override; bool TxnBegin() override; bool TxnCommit() override; bool TxnAbort() override; }; #endif // BITCOIN_WALLET_BDB_H