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/* - 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>
*
* 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 implementation of the transaction applier plugin
* for the transaction log.
*
* @see drizzled/plugin/transaction_replicator.h
* @see drizzled/plugin/transaction_applier.h
*
* @details
*
* The TransactionLogApplier::apply() method constructs the entry
* in the transaction log from the supplied Transaction message and
* asks its associated TransactionLog object to write this entry.
*
* Upon a successful write, the applier adds some information about
* the written transaction to the transaction log index.
*/
#include "config.h"
#include "write_buffer.h"
#include "transaction_log.h"
#include "transaction_log_applier.h"
#include "transaction_log_index.h"
#include <vector>
#include <drizzled/message/transaction.pb.h>
#include <drizzled/util/functors.h>
#include <drizzled/session.h>
using namespace std;
using namespace drizzled;
TransactionLogApplier *transaction_log_applier= NULL; /* The singleton transaction log applier */
TransactionLogApplier::TransactionLogApplier(const string name_arg,
TransactionLog *in_transaction_log,
TransactionLogIndex *in_transaction_log_index,
uint32_t in_num_write_buffers) :
plugin::TransactionApplier(name_arg),
transaction_log(in_transaction_log),
transaction_log_index(in_transaction_log_index),
num_write_buffers(in_num_write_buffers),
write_buffers()
{
/*
* Create each of the buffers we need for undo log entries
*/
write_buffers.reserve(num_write_buffers);
for (size_t x= 0; x < num_write_buffers; ++x)
{
write_buffers.push_back(new WriteBuffer());
}
}
TransactionLogApplier::~TransactionLogApplier()
{
for_each(write_buffers.begin(),
write_buffers.end(),
DeletePtr());
write_buffers.clear();
delete transaction_log;
delete transaction_log_index;
}
WriteBuffer *TransactionLogApplier::getWriteBuffer(const Session &session)
{
return write_buffers[session.getSessionId() % num_write_buffers];
}
plugin::ReplicationReturnCode
TransactionLogApplier::apply(Session &in_session,
const message::Transaction &to_apply)
{
size_t entry_size= TransactionLog::getLogEntrySize(to_apply);
WriteBuffer *write_buffer= getWriteBuffer(in_session);
uint32_t checksum;
write_buffer->lock();
write_buffer->resize(entry_size);
uint8_t *bytes= write_buffer->getRawBytes();
bytes= transaction_log->packTransactionIntoLogEntry(to_apply,
bytes,
&checksum);
off_t written_to= transaction_log->writeEntry(bytes, entry_size);
write_buffer->unlock();
/* Add an entry to the index describing what was just applied */
transaction_log_index->addEntry(TransactionLogEntry(ReplicationServices::TRANSACTION,
written_to,
entry_size),
to_apply,
checksum);
return plugin::SUCCESS;
}
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