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             : 
      10             : static constexpr bool DEFAULT_TXINDEX{false};
      11             : 
      12             : /**
      13             :  * TxIndex is used to look up transactions included in the blockchain by hash.
      14             :  * The index is written to a LevelDB database and records the filesystem
      15             :  * location of each transaction by transaction hash.
      16             :  */
      17             : class TxIndex final : public BaseIndex
      18             : {
      19             : protected:
      20             :     class DB;
      21             : 
      22             : private:
      23             :     const std::unique_ptr<DB> m_db;
      24             : 
      25           0 :     bool AllowPrune() const override { return false; }
      26             : 
      27             : protected:
      28             :     bool CustomAppend(const interfaces::BlockInfo& block) override;
      29             : 
      30             :     BaseIndex::DB& GetDB() const override;
      31             : 
      32             : public:
      33             :     /// Constructs the index, which becomes available to be queried.
      34             :     explicit TxIndex(std::unique_ptr<interfaces::Chain> chain, size_t n_cache_size, bool f_memory = false, bool f_wipe = false);
      35             : 
      36             :     // Destructor is declared because this class contains a unique_ptr to an incomplete type.
      37             :     virtual ~TxIndex() override;
      38             : 
      39             :     /// Look up a transaction by hash.
      40             :     ///
      41             :     /// @param[in]   tx_hash  The hash of the transaction to be returned.
      42             :     /// @param[out]  block_hash  The hash of the block the transaction is found in.
      43             :     /// @param[out]  tx  The transaction itself.
      44             :     /// @return  true if transaction is found, false otherwise
      45             :     bool FindTx(const uint256& tx_hash, uint256& block_hash, CTransactionRef& tx) const;
      46             : };
      47             : 
      48             : /// The global transaction index, used in GetTransaction. May be null.
      49             : extern std::unique_ptr<TxIndex> g_txindex;
      50             : 
      51             : #endif // BITCOIN_INDEX_TXINDEX_H