| /* |
| * Copyright (C) 2012 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. 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 distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #pragma once |
| |
| #include "Timer.h" |
| #include <wtf/Vector.h> |
| |
| namespace WebCore { |
| |
| template<typename T> class EventSender { |
| WTF_MAKE_NONCOPYABLE(EventSender); WTF_MAKE_FAST_ALLOCATED; |
| public: |
| explicit EventSender(const AtomString& eventType); |
| |
| const AtomString& eventType() const { return m_eventType; } |
| void dispatchEventSoon(T&); |
| void cancelEvent(T&); |
| void dispatchPendingEvents(); |
| |
| #if ASSERT_ENABLED |
| bool hasPendingEvents(T& sender) const |
| { |
| return m_dispatchSoonList.find(&sender) != notFound || m_dispatchingList.find(&sender) != notFound; |
| } |
| #endif |
| |
| private: |
| void timerFired() { dispatchPendingEvents(); } |
| |
| AtomString m_eventType; |
| Timer m_timer; |
| Vector<T*> m_dispatchSoonList; |
| Vector<T*> m_dispatchingList; |
| }; |
| |
| template<typename T> EventSender<T>::EventSender(const AtomString& eventType) |
| : m_eventType(eventType) |
| , m_timer(*this, &EventSender::timerFired) |
| { |
| } |
| |
| template<typename T> void EventSender<T>::dispatchEventSoon(T& sender) |
| { |
| m_dispatchSoonList.append(&sender); |
| if (!m_timer.isActive()) |
| m_timer.startOneShot(0_s); |
| } |
| |
| template<typename T> void EventSender<T>::cancelEvent(T& sender) |
| { |
| // Remove instances of this sender from both lists. |
| // Use loops because we allow multiple instances to get into the lists. |
| for (auto& event : m_dispatchSoonList) { |
| if (event == &sender) |
| event = nullptr; |
| } |
| for (auto& event : m_dispatchingList) { |
| if (event == &sender) |
| event = nullptr; |
| } |
| } |
| |
| template<typename T> void EventSender<T>::dispatchPendingEvents() |
| { |
| // Need to avoid re-entering this function; if new dispatches are |
| // scheduled before the parent finishes processing the list, they |
| // will set a timer and eventually be processed. |
| if (!m_dispatchingList.isEmpty()) |
| return; |
| |
| m_timer.stop(); |
| |
| m_dispatchSoonList.checkConsistency(); |
| |
| m_dispatchingList.swap(m_dispatchSoonList); |
| for (auto& event : m_dispatchingList) { |
| if (T* sender = event) { |
| event = nullptr; |
| sender->dispatchPendingEvent(this); |
| } |
| } |
| m_dispatchingList.clear(); |
| } |
| |
| } // namespace WebCore |