Source/platform/heap/glue/MessageLoopInterruptor.h

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#ifndef MessageLoopInterruptor_h
#define MessageLoopInterruptor_h

#include "platform/heap/ThreadState.h"
#include "public/platform/WebThread.h"

namespace blink {

class MessageLoopInterruptor : public ThreadState::Interruptor {
public:
    explicit MessageLoopInterruptor(blink::WebThread* thread) : m_thread(thread) { }

    virtual void requestInterrupt() OVERRIDE
    {
        // GCTask has an empty run() method. Its only purpose is to guarantee
        // that MessageLoop will have a task to process which will result
        // in PendingGCRunner::didProcessTask being executed.
        m_thread->postTask(new GCTask);
    }

    virtual void clearInterrupt() OVERRIDE { }

private:
    class GCTask : public blink::WebThread::Task {
    public:
        virtual ~GCTask() { }

        virtual void run() OVERRIDE
        {
            // Don't do anything here because we don't know if this is
            // a nested event loop or not. PendingGCRunner::didProcessTask
            // will enter correct safepoint for us.
            // We are not calling onInterrupted() because that always
            // conservatively enters safepoint with pointers on stack.
        }
    };

    blink::WebThread* m_thread;
};

}

#endif