Line data    Source code

       1              : // Copyright (c) 2017-2022 The Bitcoin Core developers
       2              : // Distributed under the MIT software license, see the accompanying
       3              : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       4              : 
       5              : #ifndef BITCOIN_INDEX_TXINDEX_H
       6              : #define BITCOIN_INDEX_TXINDEX_H
       7              : 
       8              : #include <index/base.h>
       9              : #include <primitives/transaction.h>
      10              : 
      11              : #include <cstddef>
      12              : #include <memory>
      13              : 
      14              : class uint256;
      15              : namespace interfaces {
      16              : class Chain;
      17              : }
      18              : 
      19              : static constexpr bool DEFAULT_TXINDEX{false};
      20              : 
      21              : /**
      22              :  * TxIndex is used to look up transactions included in the blockchain by hash.
      23              :  * The index is written to a LevelDB database and records the filesystem
      24              :  * location of each transaction by transaction hash.
      25              :  */
      26              : class TxIndex final : public BaseIndex
      27              : {
      28              : protected:
      29              :     class DB;
      30              : 
      31              : private:
      32              :     const std::unique_ptr<DB> m_db;
      33              : 
      34            0 :     bool AllowPrune() const override { return false; }
      35              : 
      36              : protected:
      37              :     bool CustomAppend(const interfaces::BlockInfo& block) override;
      38              : 
      39              :     BaseIndex::DB& GetDB() const override;
      40              : 
      41              : public:
      42              :     /// Constructs the index, which becomes available to be queried.
      43              :     explicit TxIndex(std::unique_ptr<interfaces::Chain> chain, size_t n_cache_size, bool f_memory = false, bool f_wipe = false);
      44              : 
      45              :     // Destructor is declared because this class contains a unique_ptr to an incomplete type.
      46              :     virtual ~TxIndex() override;
      47              : 
      48              :     /// Look up a transaction by hash.
      49              :     ///
      50              :     /// @param[in]   tx_hash  The hash of the transaction to be returned.
      51              :     /// @param[out]  block_hash  The hash of the block the transaction is found in.
      52              :     /// @param[out]  tx  The transaction itself.
      53              :     /// @return  true if transaction is found, false otherwise
      54              :     bool FindTx(const Txid& tx_hash, uint256& block_hash, CTransactionRef& tx) const;
      55              : };
      56              : 
      57              : /// The global transaction index, used in GetTransaction. May be null.
      58              : extern std::unique_ptr<TxIndex> g_txindex;
      59              : 
      60              : #endif // BITCOIN_INDEX_TXINDEX_H