Source/web/WorkerFileWriterCallbacksBridge.cpp

/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *     * Redistributions of source code must retain the above copyright
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 * in the documentation and/or other materials provided with the
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#include "config.h"
#include "WorkerFileWriterCallbacksBridge.h"

#include "WebFileWriter.h"
#include "WebWorkerBase.h"
#include "core/dom/CrossThreadTask.h"
#include "core/workers/WorkerGlobalScope.h"
#include "core/workers/WorkerLoaderProxy.h"
#include "core/workers/WorkerThread.h"
#include "modules/filesystem/AsyncFileWriterClient.h"
#include "public/platform/Platform.h"
#include "public/platform/WebCString.h"
#include "public/platform/WebFileSystem.h"
#include "wtf/MainThread.h"
#include "wtf/Threading.h"

using namespace WebCore;

namespace WebKit {

void WorkerFileWriterCallbacksBridge::notifyStop()
{
    ASSERT(m_workerGlobalScope->isContextThread());
    m_clientOnWorkerThread = 0;
    {
        MutexLocker locker(m_loaderProxyMutex);
        m_proxy = 0;
    }
}

void WorkerFileWriterCallbacksBridge::postWriteToMainThread(long long position, const KURL& data)
{
    ASSERT(!m_operationInProgress);
    m_operationInProgress = true;
    dispatchTaskToMainThread(createCallbackTask(&writeOnMainThread,
                                                this, position, data));
}

void WorkerFileWriterCallbacksBridge::postTruncateToMainThread(long long length)
{
    ASSERT(!m_operationInProgress);
    m_operationInProgress = true;
    dispatchTaskToMainThread(createCallbackTask(&truncateOnMainThread,
                                                this, length));
}

void WorkerFileWriterCallbacksBridge::postAbortToMainThread()
{
    ASSERT(m_operationInProgress);
    dispatchTaskToMainThread(createCallbackTask(&abortOnMainThread, this));
}

void WorkerFileWriterCallbacksBridge::postShutdownToMainThread(PassRefPtr<WorkerFileWriterCallbacksBridge> bridge)
{
    ASSERT(m_workerGlobalScope->isContextThread());
    m_clientOnWorkerThread = 0;
    stopObserving();
    dispatchTaskToMainThread(createCallbackTask(&shutdownOnMainThread, bridge));
}

void WorkerFileWriterCallbacksBridge::writeOnMainThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, long long position, const KURL& data)
{
    bridge->m_writer->write(position, WebURL(data));
}

void WorkerFileWriterCallbacksBridge::truncateOnMainThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, long long length)
{
    bridge->m_writer->truncate(length);
}

void WorkerFileWriterCallbacksBridge::abortOnMainThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge)
{
    bridge->m_writer->cancel();
}

void WorkerFileWriterCallbacksBridge::initOnMainThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, const KURL& path)
{
    ASSERT(!bridge->m_writer);
    bridge->m_writer = adoptPtr(WebKit::Platform::current()->fileSystem()->createFileWriter(path, bridge.get()));
}

void WorkerFileWriterCallbacksBridge::shutdownOnMainThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge)
{
    bridge->m_writerDeleted = true;
    bridge->m_writer.clear();
}

void WorkerFileWriterCallbacksBridge::didWrite(long long bytes, bool complete)
{
    dispatchTaskToWorkerThread(createCallbackTask(&didWriteOnWorkerThread, this, bytes, complete));
}

void WorkerFileWriterCallbacksBridge::didFail(WebFileError error)
{
    dispatchTaskToWorkerThread(createCallbackTask(&didFailOnWorkerThread, this, error));
}

void WorkerFileWriterCallbacksBridge::didTruncate()
{
    dispatchTaskToWorkerThread(createCallbackTask(&didTruncateOnWorkerThread, this));
}

static const char fileWriterOperationsMode[] = "fileWriterOperationsMode";

WorkerFileWriterCallbacksBridge::WorkerFileWriterCallbacksBridge(const KURL& path, WorkerLoaderProxy* proxy, ScriptExecutionContext* scriptExecutionContext, AsyncFileWriterClient* client)
    : WorkerGlobalScope::Observer(toWorkerGlobalScope(scriptExecutionContext))
    , m_proxy(proxy)
    , m_workerGlobalScope(scriptExecutionContext)
    , m_clientOnWorkerThread(client)
    , m_writerDeleted(false)
    , m_operationInProgress(false)
{
    ASSERT(m_workerGlobalScope->isContextThread());
    m_mode = fileWriterOperationsMode;
    m_mode.append(String::number(toWorkerGlobalScope(scriptExecutionContext)->thread()->runLoop().createUniqueId()));
    postInitToMainThread(path);
}

void WorkerFileWriterCallbacksBridge::postInitToMainThread(const KURL& path)
{
    dispatchTaskToMainThread(
        createCallbackTask(&initOnMainThread, this, path));
}

WorkerFileWriterCallbacksBridge::~WorkerFileWriterCallbacksBridge()
{
    ASSERT(!m_clientOnWorkerThread);
    ASSERT(!m_writer);
}

// We know m_clientOnWorkerThread is still valid because it is only cleared on the context thread, and because we check in runTaskOnWorkerThread before calling any of these methods.
void WorkerFileWriterCallbacksBridge::didWriteOnWorkerThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, long long length, bool complete)
{
    ASSERT(bridge->m_workerGlobalScope->isContextThread());
    ASSERT(bridge->m_operationInProgress);
    if (complete)
        bridge->m_operationInProgress = false;
    bridge->m_clientOnWorkerThread->didWrite(length, complete);
}

void WorkerFileWriterCallbacksBridge::didFailOnWorkerThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, WebFileError error)
{
    ASSERT(bridge->m_workerGlobalScope->isContextThread());
    ASSERT(bridge->m_operationInProgress);
    bridge->m_operationInProgress = false;
    bridge->m_clientOnWorkerThread->didFail(static_cast<FileError::ErrorCode>(error));
}

void WorkerFileWriterCallbacksBridge::didTruncateOnWorkerThread(ScriptExecutionContext*, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge)
{
    ASSERT(bridge->m_workerGlobalScope->isContextThread());
    ASSERT(bridge->m_operationInProgress);
    bridge->m_operationInProgress = false;
    bridge->m_clientOnWorkerThread->didTruncate();
}

void WorkerFileWriterCallbacksBridge::runTaskOnMainThread(ScriptExecutionContext* scriptExecutionContext, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, PassOwnPtr<ScriptExecutionContext::Task> taskToRun)
{
    ASSERT(isMainThread());
    if (!bridge->m_writerDeleted)
        taskToRun->performTask(scriptExecutionContext);
}

void WorkerFileWriterCallbacksBridge::runTaskOnWorkerThread(ScriptExecutionContext* scriptExecutionContext, PassRefPtr<WorkerFileWriterCallbacksBridge> bridge, PassOwnPtr<ScriptExecutionContext::Task> taskToRun)
{
    ASSERT(bridge->m_workerGlobalScope->isContextThread());
    if (bridge->m_clientOnWorkerThread)
        taskToRun->performTask(scriptExecutionContext);
}

void WorkerFileWriterCallbacksBridge::dispatchTaskToMainThread(PassOwnPtr<ScriptExecutionContext::Task> task)
{
    ASSERT(m_workerGlobalScope->isContextThread());
    WebWorkerBase::dispatchTaskToMainThread(
        createCallbackTask(&runTaskOnMainThread, this, task));
}

void WorkerFileWriterCallbacksBridge::dispatchTaskToWorkerThread(PassOwnPtr<ScriptExecutionContext::Task> task)
{
    ASSERT(isMainThread());

    MutexLocker locker(m_loaderProxyMutex);
    if (m_proxy)
        m_proxy->postTaskForModeToWorkerGlobalScope(
            createCallbackTask(&runTaskOnWorkerThread, this, task), m_mode);
}

bool WorkerFileWriterCallbacksBridge::waitForOperationToComplete()
{
    while (m_operationInProgress) {
        WorkerGlobalScope* context = toWorkerGlobalScope(m_workerGlobalScope);
        if (context->thread()->runLoop().runInMode(context, m_mode) == MessageQueueTerminated)
            return false;
    }
    return true;
}

} // namespace WebKit