third_party/WebKit/Source/core/dom/MutationObserverInterestGroup.cpp

   1 /*
   2  * Copyright (C) 2011 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "config.h"
  32
  33 #include "core/dom/MutationObserverInterestGroup.h"
  34
  35 #include "core/dom/MutationRecord.h"
  36
  37 namespace blink {
  38
  39 PassOwnPtrWillBeRawPtr<MutationObserverInterestGroup> MutationObserverInterestGroup::createIfNeeded(Node& target, MutationObserver::MutationType type, MutationRecordDeliveryOptions oldValueFlag, const QualifiedName* attributeName)
  40 {
  41     ASSERT((type == MutationObserver::Attributes && attributeName) || !attributeName);
  42     WillBeHeapHashMap<RawPtrWillBeMember<MutationObserver>, MutationRecordDeliveryOptions> observers;
  43     target.getRegisteredMutationObserversOfType(observers, type, attributeName);
  44     if (observers.isEmpty())
  45         return nullptr;
  46
  47     return adoptPtrWillBeNoop(new MutationObserverInterestGroup(observers, oldValueFlag));
  48 }
  49
  50 MutationObserverInterestGroup::MutationObserverInterestGroup(WillBeHeapHashMap<RawPtrWillBeMember<MutationObserver>, MutationRecordDeliveryOptions>& observers, MutationRecordDeliveryOptions oldValueFlag)
  51     : m_oldValueFlag(oldValueFlag)
  52 {
  53     ASSERT(!observers.isEmpty());
  54     m_observers.swap(observers);
  55 }
  56
  57 bool MutationObserverInterestGroup::isOldValueRequested()
  58 {
  59     for (auto& observer : m_observers) {
  60         if (hasOldValue(observer.value))
  61             return true;
  62     }
  63     return false;
  64 }
  65
  66 void MutationObserverInterestGroup::enqueueMutationRecord(PassRefPtrWillBeRawPtr<MutationRecord> prpMutation)
  67 {
  68     RefPtrWillBeRawPtr<MutationRecord> mutation = prpMutation;
  69     RefPtrWillBeRawPtr<MutationRecord> mutationWithNullOldValue = nullptr;
  70     for (auto& iter : m_observers) {
  71         MutationObserver* observer = iter.key;
  72         if (hasOldValue(iter.value)) {
  73             observer->enqueueMutationRecord(mutation);
  74             continue;
  75         }
  76         if (!mutationWithNullOldValue) {
  77             if (mutation->oldValue().isNull())
  78                 mutationWithNullOldValue = mutation;
  79             else
  80                 mutationWithNullOldValue = MutationRecord::createWithNullOldValue(mutation).get();
  81         }
  82         observer->enqueueMutationRecord(mutationWithNullOldValue);
  83     }
  84 }
  85
  86 DEFINE_TRACE(MutationObserverInterestGroup)
  87 {
  88 #if ENABLE(OILPAN)
  89     visitor->trace(m_observers);
  90 #endif
  91 }
  92
  93 } // namespace blink