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/*
* Copyright (C) 2008 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.
*
* 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 "config.h"
#if ENABLE(WORKERS)
#include "WorkerThread.h"
#include "DedicatedWorkerContext.h"
#include "KURL.h"
#include "PlatformString.h"
#include "ScriptSourceCode.h"
#include "ScriptValue.h"
#include "WorkerObjectProxy.h"
#include <utility>
#include <wtf/Noncopyable.h>
namespace WebCore {
struct WorkerThreadStartupData : Noncopyable {
public:
static std::auto_ptr<WorkerThreadStartupData> create(const KURL& scriptURL, const String& userAgent, const String& sourceCode)
{
return std::auto_ptr<WorkerThreadStartupData>(new WorkerThreadStartupData(scriptURL, userAgent, sourceCode));
}
KURL m_scriptURL;
String m_userAgent;
String m_sourceCode;
private:
WorkerThreadStartupData(const KURL& scriptURL, const String& userAgent, const String& sourceCode);
};
WorkerThreadStartupData::WorkerThreadStartupData(const KURL& scriptURL, const String& userAgent, const String& sourceCode)
: m_scriptURL(scriptURL.copy())
, m_userAgent(userAgent.copy())
, m_sourceCode(sourceCode.copy())
{
}
PassRefPtr<WorkerThread> WorkerThread::create(const KURL& scriptURL, const String& userAgent, const String& sourceCode, WorkerLoaderProxy& workerLoaderProxy, WorkerObjectProxy& workerObjectProxy)
{
return adoptRef(new WorkerThread(scriptURL, userAgent, sourceCode, workerLoaderProxy, workerObjectProxy));
}
WorkerThread::WorkerThread(const KURL& scriptURL, const String& userAgent, const String& sourceCode, WorkerLoaderProxy& workerLoaderProxy, WorkerObjectProxy& workerObjectProxy)
: m_threadID(0)
, m_workerLoaderProxy(workerLoaderProxy)
, m_workerObjectProxy(workerObjectProxy)
, m_startupData(WorkerThreadStartupData::create(scriptURL, userAgent, sourceCode))
{
}
WorkerThread::~WorkerThread()
{
}
bool WorkerThread::start()
{
// Mutex protection is necessary to ensure that m_threadID is initialized when the thread starts.
MutexLocker lock(m_threadCreationMutex);
if (m_threadID)
return true;
m_threadID = createThread(WorkerThread::workerThreadStart, this, "WebCore: Worker");
return m_threadID;
}
void* WorkerThread::workerThreadStart(void* thread)
{
return static_cast<WorkerThread*>(thread)->workerThread();
}
void* WorkerThread::workerThread()
{
{
MutexLocker lock(m_threadCreationMutex);
m_workerContext = DedicatedWorkerContext::create(m_startupData->m_scriptURL, m_startupData->m_userAgent, this);
if (m_runLoop.terminated()) {
// The worker was terminated before the thread had a chance to run. Since the context didn't exist yet,
// forbidExecution() couldn't be called from stop().
m_workerContext->script()->forbidExecution();
}
}
WorkerScriptController* script = m_workerContext->script();
script->evaluate(ScriptSourceCode(m_startupData->m_sourceCode, m_startupData->m_scriptURL));
// Free the startup data to cause its member variable deref's happen on the worker's thread (since
// all ref/derefs of these objects are happening on the thread at this point). Note that
// WorkerThread::~WorkerThread happens on a different thread where it was created.
m_startupData.clear();
m_workerObjectProxy.reportPendingActivity(m_workerContext->hasPendingActivity());
// Blocks until terminated.
m_runLoop.run(m_workerContext.get());
ThreadIdentifier threadID = m_threadID;
m_workerContext->stopActiveDOMObjects();
m_workerContext->clearScript();
ASSERT(m_workerContext->hasOneRef());
// The below assignment will destroy the context, which will in turn notify messaging proxy.
// We cannot let any objects survive past thread exit, because no other thread will run GC or otherwise destroy them.
m_workerContext = 0;
// The thread object may be already destroyed from notification now, don't try to access "this".
detachThread(threadID);
return 0;
}
void WorkerThread::stop()
{
// Mutex protection is necessary because stop() can be called before the context is fully created.
MutexLocker lock(m_threadCreationMutex);
// Ensure that tasks are being handled by thread event loop. If script execution weren't forbidden, a while(1) loop in JS could keep the thread alive forever.
if (m_workerContext)
m_workerContext->script()->forbidExecution();
// FIXME: Rudely killing the thread won't work when we allow nested workers, because they will try to post notifications of their destruction.
m_runLoop.terminate();
}
} // namespace WebCore
#endif // ENABLE(WORKERS)
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