third_party/WebKit/Source/core/html/parser/HTMLParserThread.cpp

/*
 * Copyright (C) 2013 Google Inc.  All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
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#include "core/html/parser/HTMLParserThread.h"

#include "platform/CrossThreadFunctional.h"
#include "platform/WaitableEvent.h"
#include "platform/heap/SafePoint.h"
#include "public/platform/Platform.h"
#include "public/platform/WebTraceLocation.h"

namespace blink {

static HTMLParserThread* s_sharedThread = nullptr;

HTMLParserThread::HTMLParserThread()
{
}

HTMLParserThread::~HTMLParserThread()
{
}

void HTMLParserThread::init()
{
    ASSERT(!s_sharedThread);
    s_sharedThread = new HTMLParserThread;
}

void HTMLParserThread::setupHTMLParserThread()
{
    ASSERT(m_thread);
    m_thread->initialize();
}

void HTMLParserThread::shutdown()
{
    ASSERT(isMainThread());
    ASSERT(s_sharedThread);
    // currentThread will always be non-null in production, but can be null in Chromium unit tests.
    if (Platform::current()->currentThread() && s_sharedThread->m_thread) {
        WaitableEvent waitableEvent;
        s_sharedThread->postTask(crossThreadBind(&HTMLParserThread::cleanupHTMLParserThread, crossThreadUnretained(s_sharedThread), crossThreadUnretained(&waitableEvent)));
        SafePointScope scope(BlinkGC::HeapPointersOnStack);
        waitableEvent.wait();
    }
    delete s_sharedThread;
    s_sharedThread = nullptr;
}

void HTMLParserThread::cleanupHTMLParserThread(WaitableEvent* waitableEvent)
{
    m_thread->shutdown();
    waitableEvent->signal();
}

HTMLParserThread* HTMLParserThread::shared()
{
    return s_sharedThread;
}

void HTMLParserThread::postTask(std::unique_ptr<CrossThreadClosure> closure)
{
    ASSERT(isMainThread());
    if (!m_thread) {
        m_thread = WebThreadSupportingGC::create("HTMLParserThread");
        postTask(crossThreadBind(&HTMLParserThread::setupHTMLParserThread, crossThreadUnretained(this)));
    }

    m_thread->postTask(BLINK_FROM_HERE, std::move(closure));
}

} // namespace blink