txindex.h raw

   1  // Copyright (c) 2017-2022 The Limenka 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 LIMENKA_INDEX_TXINDEX_H
   6  #define LIMENKA_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      bool AllowPrune() const override { return false; }
  26      bilingual_str GetDisableAction() const override { return _("set -txindex=0"); }
  27  
  28  protected:
  29      bool CustomAppend(const interfaces::BlockInfo& block) override;
  30  
  31      BaseIndex::DB& GetDB() const override;
  32  
  33  public:
  34      /// Constructs the index, which becomes available to be queried.
  35      explicit TxIndex(std::unique_ptr<interfaces::Chain> chain, size_t n_cache_size, bool f_memory = false, bool f_wipe = false);
  36  
  37      // Destructor is declared because this class contains a unique_ptr to an incomplete type.
  38      virtual ~TxIndex() override;
  39  
  40      /// Look up a transaction by hash.
  41      ///
  42      /// @param[in]   tx_hash  The hash of the transaction to be returned.
  43      /// @param[out]  block_hash  The hash of the block the transaction is found in.
  44      /// @param[out]  tx  The transaction itself.
  45      /// @return  true if transaction is found, false otherwise
  46      bool FindTx(const uint256& tx_hash, uint256& block_hash, CTransactionRef& tx) const;
  47  };
  48  
  49  /// The global transaction index, used in GetTransaction. May be null.
  50  extern std::unique_ptr<TxIndex> g_txindex;
  51  
  52  #endif // LIMENKA_INDEX_TXINDEX_H
  53