blob: f4a1750ccfd3824b3967b0719f8b22404c5c0cb2 [file] [log] [blame]
/*
* Copyright (C) 2006 Apple Computer, Inc. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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.
*/
#include "modules/webdatabase/sqlite/SQLiteTransaction.h"
#include "modules/webdatabase/sqlite/SQLiteDatabase.h"
namespace blink {
SQLiteTransaction::SQLiteTransaction(SQLiteDatabase& db, bool readOnly)
: m_db(db)
, m_inProgress(false)
, m_readOnly(readOnly)
{
}
SQLiteTransaction::~SQLiteTransaction()
{
if (m_inProgress)
rollback();
}
void SQLiteTransaction::begin()
{
if (!m_inProgress) {
ASSERT(!m_db.m_transactionInProgress);
// Call BEGIN IMMEDIATE for a write transaction to acquire
// a RESERVED lock on the DB file. Otherwise, another write
// transaction (on another connection) could make changes
// to the same DB file before this transaction gets to execute
// any statements. If that happens, this transaction will fail.
// http://www.sqlite.org/lang_transaction.html
// http://www.sqlite.org/lockingv3.html#locking
if (m_readOnly)
m_inProgress = m_db.executeCommand("BEGIN");
else
m_inProgress = m_db.executeCommand("BEGIN IMMEDIATE");
m_db.m_transactionInProgress = m_inProgress;
}
}
void SQLiteTransaction::commit()
{
if (m_inProgress) {
ASSERT(m_db.m_transactionInProgress);
m_inProgress = !m_db.executeCommand("COMMIT");
m_db.m_transactionInProgress = m_inProgress;
}
}
void SQLiteTransaction::rollback()
{
// We do not use the 'm_inProgress = m_db.executeCommand("ROLLBACK")' construct here,
// because m_inProgress should always be set to false after a ROLLBACK, and
// m_db.executeCommand("ROLLBACK") can sometimes harmlessly fail, thus returning
// a non-zero/true result (http://www.sqlite.org/lang_transaction.html).
if (m_inProgress) {
ASSERT(m_db.m_transactionInProgress);
m_db.executeCommand("ROLLBACK");
m_inProgress = false;
m_db.m_transactionInProgress = false;
}
}
void SQLiteTransaction::stop()
{
if (m_inProgress) {
m_inProgress = false;
m_db.m_transactionInProgress = false;
}
}
bool SQLiteTransaction::wasRolledBackBySqlite() const
{
// According to http://www.sqlite.org/c3ref/get_autocommit.html,
// the auto-commit flag should be off in the middle of a transaction
return m_inProgress && m_db.isAutoCommitOn();
}
} // namespace blink