blockchain/src/common/db_backend_base.h

// Copyright (c) 2014-2019 Zano Project
// Copyright (c) 2014-2018 The Louisdor Project
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#pragma once

namespace tools
{
  namespace db
  {
    typedef size_t container_handle;
    const uint64_t invalid_tx_id = 0;
    struct i_db_callback
    {
      virtual bool on_enum_item(uint64_t i, const void* pkey, uint64_t ks, const void* pval, uint64_t vs) = 0;
    };

    struct stat_info
    {
      uint64_t tx_count;
      uint64_t write_tx_count;
      uint64_t map_size;
    };

    struct i_db_backend
    {
      virtual bool close() = 0;
      virtual bool begin_transaction(bool read_only = false) = 0;
      virtual bool commit_transaction() = 0;
      virtual void abort_transaction() = 0;
      virtual bool open(const std::string& path, uint64_t flags = 0) = 0;
      virtual bool open_container(const std::string& name, container_handle& h) = 0;
      virtual bool erase(container_handle h, const char* k, size_t s) = 0;
      virtual uint64_t size(container_handle h) = 0;
      virtual bool get(container_handle h, const char* k, size_t s, std::string& res_buff) = 0;
      virtual bool set(container_handle h, const char* k, size_t s, const char* v, size_t vs) = 0;
      virtual bool clear(container_handle h) = 0;
      virtual bool enumerate(container_handle h, i_db_callback* pcb) = 0;
      virtual bool get_stat_info(stat_info& si) = 0;
      virtual ~i_db_backend() {};
    };
  }
}