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/*
* Copyright (C) 2007, 2008, 2013 Apple 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.
* 3. Neither the name of Apple Computer, Inc. ("Apple") 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 APPLE AND ITS 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 APPLE OR ITS 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 "config.h"
#include "DatabaseThread.h"
#if ENABLE(SQL_DATABASE)
#include "Database.h"
#include "DatabaseTask.h"
#include "Logging.h"
#include "SQLTransactionClient.h"
#include "SQLTransactionCoordinator.h"
#include <wtf/AutodrainedPool.h>
namespace WebCore {
DatabaseThread::DatabaseThread()
: m_threadID(0)
, m_transactionClient(adoptPtr(new SQLTransactionClient()))
, m_transactionCoordinator(adoptPtr(new SQLTransactionCoordinator()))
, m_cleanupSync(0)
{
m_selfRef = this;
}
DatabaseThread::~DatabaseThread()
{
// The DatabaseThread will only be destructed when both its owner
// DatabaseContext has deref'ed it, and the databaseThread() thread function
// has deref'ed the DatabaseThread object. The DatabaseContext destructor
// will take care of ensuring that a termination request has been issued.
// The termination request will trigger an orderly shutdown of the thread
// function databaseThread(). In shutdown, databaseThread() will deref the
// DatabaseThread before returning.
ASSERT(terminationRequested());
}
bool DatabaseThread::start()
{
MutexLocker lock(m_threadCreationMutex);
if (m_threadID)
return true;
m_threadID = createThread(DatabaseThread::databaseThreadStart, this, "WebCore: Database");
return m_threadID;
}
void DatabaseThread::requestTermination(DatabaseTaskSynchronizer *cleanupSync)
{
m_cleanupSync = cleanupSync;
LOG(StorageAPI, "DatabaseThread %p was asked to terminate\n", this);
m_queue.kill();
}
bool DatabaseThread::terminationRequested(DatabaseTaskSynchronizer* taskSynchronizer) const
{
#ifndef NDEBUG
if (taskSynchronizer)
taskSynchronizer->setHasCheckedForTermination();
#else
UNUSED_PARAM(taskSynchronizer);
#endif
return m_queue.killed();
}
void DatabaseThread::databaseThreadStart(void* vDatabaseThread)
{
DatabaseThread* dbThread = static_cast<DatabaseThread*>(vDatabaseThread);
dbThread->databaseThread();
}
void DatabaseThread::databaseThread()
{
{
// Wait for DatabaseThread::start() to complete.
MutexLocker lock(m_threadCreationMutex);
LOG(StorageAPI, "Started DatabaseThread %p", this);
}
while (OwnPtr<DatabaseTask> task = m_queue.waitForMessage()) {
AutodrainedPool pool;
task->performTask();
}
// Clean up the list of all pending transactions on this database thread
m_transactionCoordinator->shutdown();
LOG(StorageAPI, "About to detach thread %i and clear the ref to DatabaseThread %p, which currently has %i ref(s)", m_threadID, this, refCount());
// Close the databases that we ran transactions on. This ensures that if any transactions are still open, they are rolled back and we don't leave the database in an
// inconsistent or locked state.
if (m_openDatabaseSet.size() > 0) {
// As the call to close will modify the original set, we must take a copy to iterate over.
DatabaseSet openSetCopy;
openSetCopy.swap(m_openDatabaseSet);
DatabaseSet::iterator end = openSetCopy.end();
for (DatabaseSet::iterator it = openSetCopy.begin(); it != end; ++it)
(*it).get()->close();
}
// Detach the thread so its resources are no longer of any concern to anyone else
detachThread(m_threadID);
DatabaseTaskSynchronizer* cleanupSync = m_cleanupSync;
// Clear the self refptr, possibly resulting in deletion
m_selfRef = 0;
if (cleanupSync) // Someone wanted to know when we were done cleaning up.
cleanupSync->taskCompleted();
}
void DatabaseThread::recordDatabaseOpen(DatabaseBackend* database)
{
ASSERT(currentThread() == m_threadID);
ASSERT(database);
ASSERT(!m_openDatabaseSet.contains(database));
m_openDatabaseSet.add(database);
}
void DatabaseThread::recordDatabaseClosed(DatabaseBackend* database)
{
ASSERT(currentThread() == m_threadID);
ASSERT(database);
ASSERT(m_queue.killed() || m_openDatabaseSet.contains(database));
m_openDatabaseSet.remove(database);
}
void DatabaseThread::scheduleTask(PassOwnPtr<DatabaseTask> task)
{
ASSERT(!task->hasSynchronizer() || task->hasCheckedForTermination());
m_queue.append(task);
}
void DatabaseThread::scheduleImmediateTask(PassOwnPtr<DatabaseTask> task)
{
ASSERT(!task->hasSynchronizer() || task->hasCheckedForTermination());
m_queue.prepend(task);
}
class SameDatabasePredicate {
public:
SameDatabasePredicate(const DatabaseBackend* database) : m_database(database) { }
bool operator()(DatabaseTask* task) const { return task->database() == m_database; }
private:
const DatabaseBackend* m_database;
};
void DatabaseThread::unscheduleDatabaseTasks(DatabaseBackend* database)
{
// Note that the thread loop is running, so some tasks for the database
// may still be executed. This is unavoidable.
SameDatabasePredicate predicate(database);
m_queue.removeIf(predicate);
}
} // namespace WebCore
#endif
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