Source/core/dom/ScopedEventQueue.h

/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * 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
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef ScopedEventQueue_h
#define ScopedEventQueue_h

#include "wtf/Noncopyable.h"
#include "wtf/PassRefPtr.h"
#include "wtf/RefPtr.h"
#include "wtf/Vector.h"

namespace WebCore {

class EventDispatchMediator;

class ScopedEventQueue {
    WTF_MAKE_NONCOPYABLE(ScopedEventQueue); WTF_MAKE_FAST_ALLOCATED;
public:
    ~ScopedEventQueue();

    void enqueueEventDispatchMediator(PassRefPtr<EventDispatchMediator>);
    void dispatchAllEvents();
    static ScopedEventQueue* instance();

    void incrementScopingLevel();
    void decrementScopingLevel();

private:
    ScopedEventQueue();
    static void initialize();
    void dispatchEvent(PassRefPtr<EventDispatchMediator>) const;

    Vector<RefPtr<EventDispatchMediator> > m_queuedEventDispatchMediators;
    unsigned m_scopingLevel;

    static ScopedEventQueue* s_instance;
};

class EventQueueScope {
    WTF_MAKE_NONCOPYABLE(EventQueueScope);

public:
    EventQueueScope() { ScopedEventQueue::instance()->incrementScopingLevel(); }
    ~EventQueueScope() { ScopedEventQueue::instance()->decrementScopingLevel(); }
};

}

#endif // ScopedEventQueue_h