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 | #include "ChildListMutationScope.h" |
33 | |
34 | #include "MutationObserverInterestGroup.h" |
35 | #include "MutationRecord.h" |
36 | #include "StaticNodeList.h" |
37 | #include <wtf/NeverDestroyed.h> |
38 | #include <wtf/StdLibExtras.h> |
39 | |
40 | namespace WebCore { |
41 | |
42 | typedef HashMap<ContainerNode*, ChildListMutationAccumulator*> AccumulatorMap; |
43 | static AccumulatorMap& accumulatorMap() |
44 | { |
45 | static NeverDestroyed<AccumulatorMap> map; |
46 | return map; |
47 | } |
48 | |
49 | ChildListMutationAccumulator::ChildListMutationAccumulator(ContainerNode& target, std::unique_ptr<MutationObserverInterestGroup> observers) |
50 | : m_target(target) |
51 | , m_lastAdded(nullptr) |
52 | , m_observers(WTFMove(observers)) |
53 | { |
54 | } |
55 | |
56 | ChildListMutationAccumulator::~ChildListMutationAccumulator() |
57 | { |
58 | if (!isEmpty()) |
59 | enqueueMutationRecord(); |
60 | accumulatorMap().remove(m_target.ptr()); |
61 | } |
62 | |
63 | Ref<ChildListMutationAccumulator> ChildListMutationAccumulator::getOrCreate(ContainerNode& target) |
64 | { |
65 | AccumulatorMap::AddResult result = accumulatorMap().add(&target, nullptr); |
66 | RefPtr<ChildListMutationAccumulator> accumulator; |
67 | if (!result.isNewEntry) |
68 | accumulator = result.iterator->value; |
69 | else { |
70 | accumulator = adoptRef(new ChildListMutationAccumulator(target, MutationObserverInterestGroup::createForChildListMutation(target))); |
71 | result.iterator->value = accumulator.get(); |
72 | } |
73 | ASSERT(accumulator); |
74 | return accumulator.releaseNonNull(); |
75 | } |
76 | |
77 | inline bool ChildListMutationAccumulator::isAddedNodeInOrder(Node& child) |
78 | { |
79 | return isEmpty() || (m_lastAdded == child.previousSibling() && m_nextSibling == child.nextSibling()); |
80 | } |
81 | |
82 | void ChildListMutationAccumulator::childAdded(Node& childRef) |
83 | { |
84 | ASSERT(hasObservers()); |
85 | |
86 | Ref<Node> child(childRef); |
87 | |
88 | if (!isAddedNodeInOrder(child)) |
89 | enqueueMutationRecord(); |
90 | |
91 | if (isEmpty()) { |
92 | m_previousSibling = child->previousSibling(); |
93 | m_nextSibling = child->nextSibling(); |
94 | } |
95 | |
96 | m_lastAdded = child.ptr(); |
97 | m_addedNodes.append(child.get()); |
98 | } |
99 | |
100 | inline bool ChildListMutationAccumulator::isRemovedNodeInOrder(Node& child) |
101 | { |
102 | return isEmpty() || m_nextSibling == &child; |
103 | } |
104 | |
105 | void ChildListMutationAccumulator::willRemoveChild(Node& childRef) |
106 | { |
107 | ASSERT(hasObservers()); |
108 | |
109 | Ref<Node> child(childRef); |
110 | |
111 | if (!m_addedNodes.isEmpty() || !isRemovedNodeInOrder(child)) |
112 | enqueueMutationRecord(); |
113 | |
114 | if (isEmpty()) { |
115 | m_previousSibling = child->previousSibling(); |
116 | m_nextSibling = child->nextSibling(); |
117 | m_lastAdded = child->previousSibling(); |
118 | } else |
119 | m_nextSibling = child->nextSibling(); |
120 | |
121 | m_removedNodes.append(child.get()); |
122 | } |
123 | |
124 | void ChildListMutationAccumulator::enqueueMutationRecord() |
125 | { |
126 | ASSERT(hasObservers()); |
127 | ASSERT(!isEmpty()); |
128 | |
129 | auto record = MutationRecord::createChildList(m_target, StaticNodeList::create(WTFMove(m_addedNodes)), StaticNodeList::create(WTFMove(m_removedNodes)), WTFMove(m_previousSibling), WTFMove(m_nextSibling)); |
130 | m_observers->enqueueMutationRecord(WTFMove(record)); |
131 | m_lastAdded = nullptr; |
132 | ASSERT(isEmpty()); |
133 | } |
134 | |
135 | bool ChildListMutationAccumulator::isEmpty() |
136 | { |
137 | bool result = m_removedNodes.isEmpty() && m_addedNodes.isEmpty(); |
138 | #ifndef NDEBUG |
139 | if (result) { |
140 | ASSERT(!m_previousSibling); |
141 | ASSERT(!m_nextSibling); |
142 | ASSERT(!m_lastAdded); |
143 | } |
144 | #endif |
145 | return result; |
146 | } |
147 | |
148 | } // namespace WebCore |
149 | |