locked_txn.h

Go to the documentation of this file.

// Copyright (c) 2014-2020, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
//    conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
//    of conditions and the following disclaimer in the documentation and/or other
//    materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
//    used to endorse or promote products derived from this software without specific
//    prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
 
#pragma once
 
namespace cryptonote
{
    // This class is meant to create a batch when none currently exists.
    // If a batch exists, it can't be from another thread, since we can
    // only be called with the txpool lock taken, and it is held during
    // the whole prepare/handle/cleanup incoming block sequence.
    class LockedTXN {
    public:
      LockedTXN(BlockchainDB &db): m_db(db), m_batch(false), m_active(false) {
        m_batch = m_db.batch_start();
        m_active = true;
      }
      void commit() { try { if (m_batch && m_active) { m_db.batch_stop(); m_active = false; } } catch (const std::exception &e) { MWARNING("LockedTXN::commit filtering exception: " << e.what()); } }
      void abort() { try { if (m_batch && m_active) { m_db.batch_abort(); m_active = false; } } catch (const std::exception &e) { MWARNING("LockedTXN::abort filtering exception: " << e.what()); } }
      ~LockedTXN() { abort(); }
    private:
      BlockchainDB &m_db;
      bool m_batch;
      bool m_active;
    };
}