Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2021 The Bitcoin Core developers
       3             : // Distributed under the MIT software license, see the accompanying
       4             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       5             : 
       6             : #ifndef BITCOIN_WALLET_DB_H
       7             : #define BITCOIN_WALLET_DB_H
       8             : 
       9             : #include <clientversion.h>
      10             : #include <streams.h>
      11             : #include <support/allocators/secure.h>
      12             : #include <util/fs.h>
      13             : 
      14             : #include <atomic>
      15             : #include <memory>
      16             : #include <optional>
      17             : #include <string>
      18             : 
      19             : class ArgsManager;
      20             : struct bilingual_str;
      21             : 
      22             : namespace wallet {
      23             : void SplitWalletPath(const fs::path& wallet_path, fs::path& env_directory, std::string& database_filename);
      24             : 
      25             : class DatabaseCursor
      26             : {
      27             : public:
      28           0 :     explicit DatabaseCursor() {}
      29           0 :     virtual ~DatabaseCursor() {}
      30             : 
      31             :     DatabaseCursor(const DatabaseCursor&) = delete;
      32             :     DatabaseCursor& operator=(const DatabaseCursor&) = delete;
      33             : 
      34             :     enum class Status
      35             :     {
      36             :         FAIL,
      37             :         MORE,
      38             :         DONE,
      39             :     };
      40             : 
      41           0 :     virtual Status Next(DataStream& key, DataStream& value) { return Status::FAIL; }
      42             : };
      43             : 
      44             : /** RAII class that provides access to a WalletDatabase */
      45             : class DatabaseBatch
      46             : {
      47             : private:
      48             :     virtual bool ReadKey(DataStream&& key, DataStream& value) = 0;
      49             :     virtual bool WriteKey(DataStream&& key, DataStream&& value, bool overwrite = true) = 0;
      50             :     virtual bool EraseKey(DataStream&& key) = 0;
      51             :     virtual bool HasKey(DataStream&& key) = 0;
      52             : 
      53             : public:
      54           0 :     explicit DatabaseBatch() {}
      55           0 :     virtual ~DatabaseBatch() {}
      56             : 
      57             :     DatabaseBatch(const DatabaseBatch&) = delete;
      58             :     DatabaseBatch& operator=(const DatabaseBatch&) = delete;
      59             : 
      60             :     virtual void Flush() = 0;
      61             :     virtual void Close() = 0;
      62             : 
      63             :     template <typename K, typename T>
      64           0 :     bool Read(const K& key, T& value)
      65             :     {
      66           0 :         DataStream ssKey{};
      67           0 :         ssKey.reserve(1000);
      68           0 :         ssKey << key;
      69             : 
      70           0 :         CDataStream ssValue(SER_DISK, CLIENT_VERSION);
      71           0 :         if (!ReadKey(std::move(ssKey), ssValue)) return false;
      72             :         try {
      73           0 :             ssValue >> value;
      74           0 :             return true;
      75           0 :         } catch (const std::exception&) {
      76           0 :             return false;
      77           0 :         }
      78           0 :     }
      79             : 
      80             :     template <typename K, typename T>
      81           0 :     bool Write(const K& key, const T& value, bool fOverwrite = true)
      82             :     {
      83           0 :         DataStream ssKey{};
      84           0 :         ssKey.reserve(1000);
      85           0 :         ssKey << key;
      86             : 
      87           0 :         CDataStream ssValue(SER_DISK, CLIENT_VERSION);
      88           0 :         ssValue.reserve(10000);
      89           0 :         ssValue << value;
      90             : 
      91           0 :         return WriteKey(std::move(ssKey), std::move(ssValue), fOverwrite);
      92           0 :     }
      93             : 
      94             :     template <typename K>
      95           0 :     bool Erase(const K& key)
      96             :     {
      97           0 :         DataStream ssKey{};
      98           0 :         ssKey.reserve(1000);
      99           0 :         ssKey << key;
     100             : 
     101           0 :         return EraseKey(std::move(ssKey));
     102           0 :     }
     103             : 
     104             :     template <typename K>
     105             :     bool Exists(const K& key)
     106             :     {
     107             :         DataStream ssKey{};
     108             :         ssKey.reserve(1000);
     109             :         ssKey << key;
     110             : 
     111             :         return HasKey(std::move(ssKey));
     112             :     }
     113             :     virtual bool ErasePrefix(Span<const std::byte> prefix) = 0;
     114             : 
     115             :     virtual std::unique_ptr<DatabaseCursor> GetNewCursor() = 0;
     116             :     virtual std::unique_ptr<DatabaseCursor> GetNewPrefixCursor(Span<const std::byte> prefix) = 0;
     117             :     virtual bool TxnBegin() = 0;
     118             :     virtual bool TxnCommit() = 0;
     119             :     virtual bool TxnAbort() = 0;
     120             : };
     121             : 
     122             : /** An instance of this class represents one database.
     123             :  **/
     124             : class WalletDatabase
     125             : {
     126             : public:
     127             :     /** Create dummy DB handle */
     128           0 :     WalletDatabase() : nUpdateCounter(0) {}
     129           0 :     virtual ~WalletDatabase() {};
     130             : 
     131             :     /** Open the database if it is not already opened. */
     132             :     virtual void Open() = 0;
     133             : 
     134             :     //! Counts the number of active database users to be sure that the database is not closed while someone is using it
     135           0 :     std::atomic<int> m_refcount{0};
     136             :     /** Indicate the a new database user has began using the database. Increments m_refcount */
     137             :     virtual void AddRef() = 0;
     138             :     /** Indicate that database user has stopped using the database and that it could be flushed or closed. Decrement m_refcount */
     139             :     virtual void RemoveRef() = 0;
     140             : 
     141             :     /** Rewrite the entire database on disk, with the exception of key pszSkip if non-zero
     142             :      */
     143             :     virtual bool Rewrite(const char* pszSkip=nullptr) = 0;
     144             : 
     145             :     /** Back up the entire database to a file.
     146             :      */
     147             :     virtual bool Backup(const std::string& strDest) const = 0;
     148             : 
     149             :     /** Make sure all changes are flushed to database file.
     150             :      */
     151             :     virtual void Flush() = 0;
     152             :     /** Flush to the database file and close the database.
     153             :      *  Also close the environment if no other databases are open in it.
     154             :      */
     155             :     virtual void Close() = 0;
     156             :     /* flush the wallet passively (TRY_LOCK)
     157             :        ideal to be called periodically */
     158             :     virtual bool PeriodicFlush() = 0;
     159             : 
     160             :     virtual void IncrementUpdateCounter() = 0;
     161             : 
     162             :     virtual void ReloadDbEnv() = 0;
     163             : 
     164             :     /** Return path to main database file for logs and error messages. */
     165             :     virtual std::string Filename() = 0;
     166             : 
     167             :     virtual std::string Format() = 0;
     168             : 
     169             :     std::atomic<unsigned int> nUpdateCounter;
     170           0 :     unsigned int nLastSeen{0};
     171           0 :     unsigned int nLastFlushed{0};
     172           0 :     int64_t nLastWalletUpdate{0};
     173             : 
     174             :     /** Make a DatabaseBatch connected to this database */
     175             :     virtual std::unique_ptr<DatabaseBatch> MakeBatch(bool flush_on_close = true) = 0;
     176             : };
     177             : 
     178             : enum class DatabaseFormat {
     179             :     BERKELEY,
     180             :     SQLITE,
     181             : };
     182             : 
     183           0 : struct DatabaseOptions {
     184           0 :     bool require_existing = false;
     185           0 :     bool require_create = false;
     186             :     std::optional<DatabaseFormat> require_format;
     187           0 :     uint64_t create_flags = 0;
     188             :     SecureString create_passphrase;
     189             : 
     190             :     // Specialized options. Not every option is supported by every backend.
     191           0 :     bool verify = true;             //!< Check data integrity on load.
     192           0 :     bool use_unsafe_sync = false;   //!< Disable file sync for faster performance.
     193           0 :     bool use_shared_memory = false; //!< Let other processes access the database.
     194           0 :     int64_t max_log_mb = 100;       //!< Max log size to allow before consolidating.
     195             : };
     196             : 
     197             : enum class DatabaseStatus {
     198             :     SUCCESS,
     199             :     FAILED_BAD_PATH,
     200             :     FAILED_BAD_FORMAT,
     201             :     FAILED_ALREADY_LOADED,
     202             :     FAILED_ALREADY_EXISTS,
     203             :     FAILED_NOT_FOUND,
     204             :     FAILED_CREATE,
     205             :     FAILED_LOAD,
     206             :     FAILED_VERIFY,
     207             :     FAILED_ENCRYPT,
     208             :     FAILED_INVALID_BACKUP_FILE,
     209             : };
     210             : 
     211             : /** Recursively list database paths in directory. */
     212             : std::vector<fs::path> ListDatabases(const fs::path& path);
     213             : 
     214             : void ReadDatabaseArgs(const ArgsManager& args, DatabaseOptions& options);
     215             : std::unique_ptr<WalletDatabase> MakeDatabase(const fs::path& path, const DatabaseOptions& options, DatabaseStatus& status, bilingual_str& error);
     216             : 
     217             : fs::path BDBDataFile(const fs::path& path);
     218             : fs::path SQLiteDataFile(const fs::path& path);
     219             : bool IsBDBFile(const fs::path& path);
     220             : bool IsSQLiteFile(const fs::path& path);
     221             : } // namespace wallet
     222             : 
     223             : #endif // BITCOIN_WALLET_DB_H