~drizzle-trunk/drizzle/development

/* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2008-2009 Sun Microsystems

 *  Copyright (c) 2010 Jay Pipes <jaypipes@gmail.com>

 *

 *  Authors:

 *

 *  Jay Pipes <jaypipes@gmail.com.com>

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

/**

 * @file

 *

 * Defines the API of the transaction log applier.

 *

 * @see drizzled/plugin/replicator.h

 * @see drizzled/plugin/applier.h

 */

#ifndef PLUGIN_TRANSACTION_LOG_TRANSACTION_LOG_APPLIER_H

#define PLUGIN_TRANSACTION_LOG_TRANSACTION_LOG_APPLIER_H

#include <drizzled/replication_services.h>

#include <drizzled/plugin/transaction_applier.h>

#include "transaction_log_entry.h"

#include <vector>

#include <string>

namespace drizzled

{

  class Session;

}

class TransactionLog;

class TransactionLogIndex;

class WriteBuffer;

class TransactionLogApplier: public drizzled::plugin::TransactionApplier 

{

public:

  TransactionLogApplier(const std::string name_arg,

                        TransactionLog *in_transaction_log,

                        TransactionLogIndex *in_transaction_log_index,

                        uint32_t in_num_write_buffers);

  /** Destructor */

  ~TransactionLogApplier();

  /**

   * Applies a Transaction to the serial log

   *

   * @note

   *

   * It is important to note that memory allocation for the 

   * supplied pointer is not guaranteed after the completion 

   * of this function -- meaning the caller can dispose of the

   * supplied message.  Therefore, appliers which are

   * implementing an asynchronous replication system must copy

   * the supplied message to their own controlled memory storage

   * area.

   *

   * @param Session descriptor

   * @param Transaction message to be replicated

   */

  drizzled::plugin::ReplicationReturnCode

  apply(drizzled::Session &in_session,

        const drizzled::message::Transaction &to_apply);

private:

  /* Don't allows these */

  TransactionLogApplier();

  TransactionLogApplier(const TransactionLogApplier &other);

  TransactionLogApplier &operator=(const TransactionLogApplier &other);

  /** 

   * This Applier owns the memory of the associated TransactionLog 

   * and its index - so we have to track it. 

   */

  TransactionLog *transaction_log;

  TransactionLogIndex *transaction_log_index;

  uint32_t num_write_buffers; ///< Number of write buffers used

  std::vector<WriteBuffer *> write_buffers; ///< array of write buffers

  /**

   * Returns the write buffer for the supplied session

   *

   * @param Session descriptor

   */

  WriteBuffer *getWriteBuffer(const drizzled::Session &session);

};

#endif /* PLUGIN_TRANSACTION_LOG_TRANSACTION_LOG_APPLIER_H */