third_party/WebKit/Source/core/dom/custom/V0CustomElementCallbackQueue.cpp

/*
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 *    software without specific prior written permission.
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#include "core/dom/custom/V0CustomElementCallbackQueue.h"

#include "core/dom/shadow/ShadowRoot.h"

namespace blink {

V0CustomElementCallbackQueue* V0CustomElementCallbackQueue::create(Element* element)
{
    return new V0CustomElementCallbackQueue(element);
}

V0CustomElementCallbackQueue::V0CustomElementCallbackQueue(Element* element)
    : m_element(element)
    , m_owner(-1)
    , m_index(0)
    , m_inCreatedCallback(false)
{
}

bool V0CustomElementCallbackQueue::processInElementQueue(ElementQueueId caller)
{
    DCHECK(!m_inCreatedCallback);
    bool didWork = false;

    // Never run custom element callbacks in UA shadow roots since that would
    // leak the UA root and it's elements into the page.
    ShadowRoot* shadowRoot = m_element->containingShadowRoot();
    if (!shadowRoot || shadowRoot->type() != ShadowRootType::UserAgent) {
        while (m_index < m_queue.size() && owner() == caller) {
            m_inCreatedCallback = m_queue[m_index]->isCreatedCallback();

            // dispatch() may cause recursion which steals this callback
            // queue and reenters processInQueue. owner() == caller
            // detects this recursion and cedes processing.
            m_queue[m_index++]->dispatch(m_element.get());
            m_inCreatedCallback = false;
            didWork = true;
        }
    }

    if (owner() == caller && m_index == m_queue.size()) {
        // This processInQueue exhausted the queue; shrink it.
        m_index = 0;
        m_queue.resize(0);
        m_owner = -1;
    }

    return didWork;
}

DEFINE_TRACE(V0CustomElementCallbackQueue)
{
    visitor->trace(m_element);
    visitor->trace(m_queue);
}

} // namespace blink