src/third_party/WebKit/Source/core/dom/ContextLifecycleNotifier.cpp

   1 /*
   2  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
   3  * Copyright (C) 2013 Google Inc. All Rights Reserved.
   4  *
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   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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  24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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  27
  28 #include "config.h"
  29 #include "core/dom/ContextLifecycleNotifier.h"
  30
  31 #include "core/dom/ExecutionContext.h"
  32 #include "wtf/TemporaryChange.h"
  33
  34 namespace blink {
  35
  36 ContextLifecycleNotifier::ContextLifecycleNotifier(ExecutionContext* context)
  37     : LifecycleNotifier<ExecutionContext>(context)
  38 {
  39 }
  40
  41 ContextLifecycleNotifier::~ContextLifecycleNotifier()
  42 {
  43 }
  44
  45 void ContextLifecycleNotifier::addObserver(ContextLifecycleNotifier::Observer* observer)
  46 {
  47     LifecycleNotifier<ExecutionContext>::addObserver(observer);
  48
  49     RELEASE_ASSERT(m_iterating != IteratingOverContextObservers);
  50     if (observer->observerType() == Observer::ActiveDOMObjectType) {
  51         RELEASE_ASSERT(m_iterating != IteratingOverActiveDOMObjects);
  52         m_activeDOMObjects.add(static_cast<ActiveDOMObject*>(observer));
  53     }
  54 }
  55
  56 void ContextLifecycleNotifier::removeObserver(ContextLifecycleNotifier::Observer* observer)
  57 {
  58     LifecycleNotifier<ExecutionContext>::removeObserver(observer);
  59
  60     RELEASE_ASSERT(m_iterating != IteratingOverContextObservers);
  61     if (observer->observerType() == Observer::ActiveDOMObjectType) {
  62         m_activeDOMObjects.remove(static_cast<ActiveDOMObject*>(observer));
  63     }
  64 }
  65
  66 void ContextLifecycleNotifier::notifyResumingActiveDOMObjects()
  67 {
  68     TemporaryChange<IterationType> scope(this->m_iterating, IteratingOverActiveDOMObjects);
  69     Vector<ActiveDOMObject*> snapshotOfActiveDOMObjects;
  70     copyToVector(m_activeDOMObjects, snapshotOfActiveDOMObjects);
  71     for (ActiveDOMObject* obj : snapshotOfActiveDOMObjects) {
  72         // FIXME: Oilpan: At the moment, it's possible that the ActiveDOMObject is destructed
  73         // during the iteration. Once we move ActiveDOMObject to the heap and
  74         // make m_activeDOMObjects a HeapHashSet<WeakMember<ActiveDOMObject>>,
  75         // it's no longer possible that ActiveDOMObject is destructed during the iteration,
  76         // so we can remove the hack (i.e., we can just iterate m_activeDOMObjects without
  77         // taking a snapshot). For more details, see https://codereview.chromium.org/247253002/.
  78         if (m_activeDOMObjects.contains(obj)) {
  79             ASSERT(obj->executionContext() == context());
  80             ASSERT(obj->suspendIfNeededCalled());
  81             obj->resume();
  82         }
  83     }
  84 }
  85
  86 void ContextLifecycleNotifier::notifySuspendingActiveDOMObjects()
  87 {
  88     TemporaryChange<IterationType> scope(this->m_iterating, IteratingOverActiveDOMObjects);
  89     Vector<ActiveDOMObject*> snapshotOfActiveDOMObjects;
  90     copyToVector(m_activeDOMObjects, snapshotOfActiveDOMObjects);
  91     for (ActiveDOMObject* obj : snapshotOfActiveDOMObjects) {
  92         // It's possible that the ActiveDOMObject is already destructed.
  93         // See a FIXME above.
  94         if (m_activeDOMObjects.contains(obj)) {
  95             ASSERT(obj->executionContext() == context());
  96             ASSERT(obj->suspendIfNeededCalled());
  97             obj->suspend();
  98         }
  99     }
 100 }
 101
 102 void ContextLifecycleNotifier::notifyStoppingActiveDOMObjects()
 103 {
 104     TemporaryChange<IterationType> scope(this->m_iterating, IteratingOverActiveDOMObjects);
 105     Vector<ActiveDOMObject*> snapshotOfActiveDOMObjects;
 106     copyToVector(m_activeDOMObjects, snapshotOfActiveDOMObjects);
 107     for (ActiveDOMObject* obj : snapshotOfActiveDOMObjects) {
 108         // It's possible that the ActiveDOMObject is already destructed.
 109         // See a FIXME above.
 110         if (m_activeDOMObjects.contains(obj)) {
 111             ASSERT(obj->executionContext() == context());
 112             ASSERT(obj->suspendIfNeededCalled());
 113             obj->stop();
 114         }
 115     }
 116 }
 117
 118 bool ContextLifecycleNotifier::hasPendingActivity() const
 119 {
 120     for (ActiveDOMObject* obj : m_activeDOMObjects) {
 121         if (obj->hasPendingActivity())
 122             return true;
 123     }
 124     return false;
 125 }
 126
 127 } // namespace blink