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 | #pragma once |
32 | |
33 | #include "ContainerNode.h" |
34 | #include "Document.h" |
35 | #include "MutationObserver.h" |
36 | #include <memory> |
37 | #include <wtf/Noncopyable.h> |
38 | #include <wtf/RefCounted.h> |
39 | |
40 | namespace WebCore { |
41 | |
42 | class MutationObserverInterestGroup; |
43 | |
44 | // ChildListMutationAccumulator is not meant to be used directly; ChildListMutationScope is the public interface. |
45 | class ChildListMutationAccumulator : public RefCounted<ChildListMutationAccumulator> { |
46 | public: |
47 | static Ref<ChildListMutationAccumulator> getOrCreate(ContainerNode&); |
48 | ~ChildListMutationAccumulator(); |
49 | |
50 | void childAdded(Node&); |
51 | void willRemoveChild(Node&); |
52 | |
53 | bool hasObservers() const { return !!m_observers; } |
54 | |
55 | private: |
56 | ChildListMutationAccumulator(ContainerNode&, std::unique_ptr<MutationObserverInterestGroup>); |
57 | |
58 | void enqueueMutationRecord(); |
59 | bool isEmpty(); |
60 | bool isAddedNodeInOrder(Node&); |
61 | bool isRemovedNodeInOrder(Node&); |
62 | |
63 | Ref<ContainerNode> m_target; |
64 | |
65 | Vector<Ref<Node>> m_removedNodes; |
66 | Vector<Ref<Node>> m_addedNodes; |
67 | RefPtr<Node> m_previousSibling; |
68 | RefPtr<Node> m_nextSibling; |
69 | Node* m_lastAdded; |
70 | |
71 | std::unique_ptr<MutationObserverInterestGroup> m_observers; |
72 | }; |
73 | |
74 | class ChildListMutationScope { |
75 | WTF_MAKE_NONCOPYABLE(ChildListMutationScope); |
76 | public: |
77 | explicit ChildListMutationScope(ContainerNode& target) |
78 | { |
79 | if (target.document().hasMutationObserversOfType(MutationObserver::ChildList)) |
80 | m_accumulator = ChildListMutationAccumulator::getOrCreate(target); |
81 | } |
82 | |
83 | bool canObserve() const { return m_accumulator; } |
84 | |
85 | void childAdded(Node& child) |
86 | { |
87 | if (m_accumulator && m_accumulator->hasObservers()) |
88 | m_accumulator->childAdded(child); |
89 | } |
90 | |
91 | void willRemoveChild(Node& child) |
92 | { |
93 | if (m_accumulator && m_accumulator->hasObservers()) |
94 | m_accumulator->willRemoveChild(child); |
95 | } |
96 | |
97 | private: |
98 | RefPtr<ChildListMutationAccumulator> m_accumulator; |
99 | }; |
100 | |
101 | } // namespace WebCore |
102 | |