third_party/WebKit/Source/core/dom/MutationObserverRegistration.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/MutationObserverRegistration.h"
  34
  35 #include "core/dom/Node.h"
  36 #include "core/dom/QualifiedName.h"
  37
  38 namespace blink {
  39
  40 PassOwnPtrWillBeRawPtr<MutationObserverRegistration> MutationObserverRegistration::create(MutationObserver& observer, Node* registrationNode, MutationObserverOptions options, const HashSet<AtomicString>& attributeFilter)
  41 {
  42     return adoptPtrWillBeNoop(new MutationObserverRegistration(observer, registrationNode, options, attributeFilter));
  43 }
  44
  45 MutationObserverRegistration::MutationObserverRegistration(MutationObserver& observer, Node* registrationNode, MutationObserverOptions options, const HashSet<AtomicString>& attributeFilter)
  46     : m_observer(observer)
  47     , m_registrationNode(registrationNode)
  48     , m_options(options)
  49     , m_attributeFilter(attributeFilter)
  50 {
  51     m_observer->observationStarted(this);
  52 }
  53
  54 MutationObserverRegistration::~MutationObserverRegistration()
  55 {
  56 #if !ENABLE(OILPAN)
  57     dispose();
  58 #endif
  59 }
  60
  61 void MutationObserverRegistration::dispose()
  62 {
  63     clearTransientRegistrations();
  64     m_observer->observationEnded(this);
  65     m_observer.clear();
  66 }
  67
  68 void MutationObserverRegistration::resetObservation(MutationObserverOptions options, const HashSet<AtomicString>& attributeFilter)
  69 {
  70     clearTransientRegistrations();
  71     m_options = options;
  72     m_attributeFilter = attributeFilter;
  73 }
  74
  75 void MutationObserverRegistration::observedSubtreeNodeWillDetach(Node& node)
  76 {
  77     if (!isSubtree())
  78         return;
  79
  80     node.registerTransientMutationObserver(this);
  81     m_observer->setHasTransientRegistration();
  82
  83     if (!m_transientRegistrationNodes) {
  84         m_transientRegistrationNodes = adoptPtrWillBeNoop(new NodeHashSet);
  85
  86         ASSERT(m_registrationNode);
  87         ASSERT(!m_registrationNodeKeepAlive);
  88         m_registrationNodeKeepAlive = PassRefPtrWillBeRawPtr<Node>(m_registrationNode.get()); // Balanced in clearTransientRegistrations.
  89     }
  90     m_transientRegistrationNodes->add(&node);
  91 }
  92
  93 void MutationObserverRegistration::clearTransientRegistrations()
  94 {
  95     if (!m_transientRegistrationNodes) {
  96         ASSERT(!m_registrationNodeKeepAlive);
  97         return;
  98     }
  99
 100     for (auto& node : *m_transientRegistrationNodes)
 101         node->unregisterTransientMutationObserver(this);
 102
 103     m_transientRegistrationNodes.clear();
 104
 105     ASSERT(m_registrationNodeKeepAlive);
 106     m_registrationNodeKeepAlive = nullptr; // Balanced in observeSubtreeNodeWillDetach.
 107 }
 108
 109 void MutationObserverRegistration::unregister()
 110 {
 111     ASSERT(m_registrationNode);
 112     m_registrationNode->unregisterMutationObserver(this);
 113     // The above line will cause this object to be deleted, so don't do any more in this function.
 114 }
 115
 116 bool MutationObserverRegistration::shouldReceiveMutationFrom(Node& node, MutationObserver::MutationType type, const QualifiedName* attributeName) const
 117 {
 118     ASSERT((type == MutationObserver::Attributes && attributeName) || !attributeName);
 119     if (!(m_options & type))
 120         return false;
 121
 122     if (m_registrationNode != &node && !isSubtree())
 123         return false;
 124
 125     if (type != MutationObserver::Attributes || !(m_options & MutationObserver::AttributeFilter))
 126         return true;
 127
 128     if (!attributeName->namespaceURI().isNull())
 129         return false;
 130
 131     return m_attributeFilter.contains(attributeName->localName());
 132 }
 133
 134 void MutationObserverRegistration::addRegistrationNodesToSet(WillBeHeapHashSet<RawPtrWillBeMember<Node>>& nodes) const
 135 {
 136     ASSERT(m_registrationNode);
 137     nodes.add(m_registrationNode.get());
 138     if (!m_transientRegistrationNodes)
 139         return;
 140     for (NodeHashSet::const_iterator iter = m_transientRegistrationNodes->begin(); iter != m_transientRegistrationNodes->end(); ++iter)
 141         nodes.add(iter->get());
 142 }
 143
 144 DEFINE_TRACE(MutationObserverRegistration)
 145 {
 146     visitor->trace(m_observer);
 147     visitor->trace(m_registrationNode);
 148     visitor->trace(m_registrationNodeKeepAlive);
 149 #if ENABLE(OILPAN)
 150     visitor->trace(m_transientRegistrationNodes);
 151 #endif
 152 }
 153
 154 } // namespace blink