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 "MutationObserverRegistration.h"
34
35#include "Document.h"
36#include "QualifiedName.h"
37
38namespace WebCore {
39
40MutationObserverRegistration::MutationObserverRegistration(MutationObserver& observer, Node& node, MutationObserverOptions options, const HashSet<AtomicString>& attributeFilter)
41 : m_observer(observer)
42 , m_node(node)
43 , m_options(options)
44 , m_attributeFilter(attributeFilter)
45{
46 m_observer->observationStarted(*this);
47}
48
49MutationObserverRegistration::~MutationObserverRegistration()
50{
51 takeTransientRegistrations();
52 m_observer->observationEnded(*this);
53}
54
55void MutationObserverRegistration::resetObservation(MutationObserverOptions options, const HashSet<AtomicString>& attributeFilter)
56{
57 takeTransientRegistrations();
58 m_options = options;
59 m_attributeFilter = attributeFilter;
60}
61
62void MutationObserverRegistration::observedSubtreeNodeWillDetach(Node& node)
63{
64 if (!isSubtree())
65 return;
66
67 node.registerTransientMutationObserver(*this);
68 m_observer->setHasTransientRegistration();
69
70 if (!m_transientRegistrationNodes) {
71 m_transientRegistrationNodes = std::make_unique<HashSet<GCReachableRef<Node>>>();
72
73 ASSERT(!m_nodeKeptAlive);
74 m_nodeKeptAlive = &m_node; // Balanced in takeTransientRegistrations.
75 }
76 m_transientRegistrationNodes->add(node);
77}
78
79std::unique_ptr<HashSet<GCReachableRef<Node>>> MutationObserverRegistration::takeTransientRegistrations()
80{
81 if (!m_transientRegistrationNodes) {
82 ASSERT(!m_nodeKeptAlive);
83 return nullptr;
84 }
85
86 for (auto& node : *m_transientRegistrationNodes)
87 node->unregisterTransientMutationObserver(*this);
88
89 auto returnValue = WTFMove(m_transientRegistrationNodes);
90
91 ASSERT(m_nodeKeptAlive);
92 m_nodeKeptAlive = nullptr; // Balanced in observeSubtreeNodeWillDetach.
93
94 return returnValue;
95}
96
97bool MutationObserverRegistration::shouldReceiveMutationFrom(Node& node, MutationObserver::MutationType type, const QualifiedName* attributeName) const
98{
99 ASSERT((type == MutationObserver::Attributes && attributeName) || !attributeName);
100 if (!(m_options & type))
101 return false;
102
103 if (&m_node != &node && !isSubtree())
104 return false;
105
106 if (type != MutationObserver::Attributes || !(m_options & MutationObserver::AttributeFilter))
107 return true;
108
109 if (!attributeName->namespaceURI().isNull())
110 return false;
111
112 return m_attributeFilter.contains(attributeName->localName());
113}
114
115void MutationObserverRegistration::addRegistrationNodesToSet(HashSet<Node*>& nodes) const
116{
117 nodes.add(&m_node);
118 if (!m_transientRegistrationNodes)
119 return;
120 for (auto& node : *m_transientRegistrationNodes)
121 nodes.add(node.ptr());
122}
123
124} // namespace WebCore
125