Source/WebCore/dom/ScopedEventQueue.cpp

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#include "config.h"
#include "ScopedEventQueue.h"

#include "Event.h"
#include "EventDispatcher.h"
#include "EventTarget.h"

namespace WebCore {

ScopedEventQueue& ScopedEventQueue::singleton()
{
    static NeverDestroyed<ScopedEventQueue> scopedEventQueue;
    return scopedEventQueue;
}

void ScopedEventQueue::enqueueEvent(Ref<Event>&& event)
{
    if (m_scopingLevel)
        m_queuedEvents.append(WTFMove(event));
    else
        dispatchEvent(event);
}

void ScopedEventQueue::dispatchEvent(Event& event) const
{
    ASSERT(event.target());
    // Store the target in a local variable to avoid possibly dereferencing a nullified PassRefPtr after it's passed on.
    Node* node = event.target()->toNode();
    EventDispatcher::dispatchEvent(node, event);
}

void ScopedEventQueue::dispatchAllEvents()
{
    Vector<Ref<Event>> queuedEvents = WTFMove(m_queuedEvents);
    for (auto& queuedEvent : queuedEvents)
        dispatchEvent(queuedEvent);
}

void ScopedEventQueue::incrementScopingLevel()
{
    ++m_scopingLevel;
}

void ScopedEventQueue::decrementScopingLevel()
{
    ASSERT(m_scopingLevel);
    --m_scopingLevel;
    if (!m_scopingLevel)
        dispatchAllEvents();
}

}