1 /*
2 * Copyright (C) 2011 Google Inc. All Rights Reserved.
3 * Copyright (C) 2012 Apple Inc. All Rights Reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #ifndef TreeScope_h
28 #define TreeScope_h
29
30 #include "core/dom/DocumentOrderedMap.h"
31 #include "wtf/Forward.h"
32 #include "wtf/text/AtomicString.h"
33
34 namespace WebCore {
35
36 class ContainerNode;
37 class DOMSelection;
38 class Document;
39 class Element;
40 class HTMLLabelElement;
41 class HTMLMapElement;
42 class LayoutPoint;
43 class IdTargetObserverRegistry;
44 class Node;
45 class RenderObject;
46
47 // A class which inherits both Node and TreeScope must call clearRareData() in its destructor
48 // so that the Node destructor no longer does problematic NodeList cache manipulation in
49 // the destructor.
50 class TreeScope {
51 friend class Document;
52 friend class TreeScopeAdopter;
53
54 public:
parentTreeScope()55 TreeScope* parentTreeScope() const { return m_parentTreeScope; }
56 void setParentTreeScope(TreeScope*);
57
58 Element* adjustedFocusedElement() const;
59 Element* getElementById(const AtomicString&) const;
60 bool hasElementWithId(StringImpl* id) const;
61 bool containsMultipleElementsWithId(const AtomicString& id) const;
62 void addElementById(const AtomicString& elementId, Element*);
63 void removeElementById(const AtomicString& elementId, Element*);
64
documentScope()65 Document* documentScope() const { return m_documentScope; }
66
67 Node* ancestorInThisScope(Node*) const;
68
69 void addImageMap(HTMLMapElement*);
70 void removeImageMap(HTMLMapElement*);
71 HTMLMapElement* getImageMap(const String& url) const;
72
73 Element* elementFromPoint(int x, int y) const;
74
75 // For accessibility.
shouldCacheLabelsByForAttribute()76 bool shouldCacheLabelsByForAttribute() const { return m_labelsByForAttribute; }
77 void addLabel(const AtomicString& forAttributeValue, HTMLLabelElement*);
78 void removeLabel(const AtomicString& forAttributeValue, HTMLLabelElement*);
79 HTMLLabelElement* labelElementForId(const AtomicString& forAttributeValue);
80
81 DOMSelection* getSelection() const;
82
83 // Find first anchor with the given name.
84 // First searches for an element with the given ID, but if that fails, then looks
85 // for an anchor with the given name. ID matching is always case sensitive, but
86 // Anchor name matching is case sensitive in strict mode and not case sensitive in
87 // quirks mode for historical compatibility reasons.
88 Element* findAnchor(const String& name);
89
90 bool applyAuthorStyles() const;
91
92 // Used by the basic DOM mutation methods (e.g., appendChild()).
93 void adoptIfNeeded(Node&);
94
rootNode()95 Node* rootNode() const { return m_rootNode; }
96
idTargetObserverRegistry()97 IdTargetObserverRegistry& idTargetObserverRegistry() const { return *m_idTargetObserverRegistry.get(); }
98
99 // Nodes belonging to this scope hold guard references -
100 // these are enough to keep the scope from being destroyed, but
101 // not enough to keep it from removing its children. This allows a
102 // node that outlives its scope to still have a valid document
103 // pointer without introducing reference cycles.
guardRef()104 void guardRef()
105 {
106 ASSERT(!deletionHasBegun());
107 ++m_guardRefCount;
108 }
109
guardDeref()110 void guardDeref()
111 {
112 ASSERT(!deletionHasBegun());
113 --m_guardRefCount;
114 if (!m_guardRefCount && !refCount() && !rootNodeHasTreeSharedParent()) {
115 beginDeletion();
116 delete this;
117 }
118 }
119
120 void removedLastRefToScope();
121
122 bool isInclusiveAncestorOf(const TreeScope&) const;
123 unsigned short comparePosition(const TreeScope&) const;
124
125 Element* getElementByAccessKey(const String& key) const;
126
127 protected:
128 TreeScope(ContainerNode*, Document*);
129 TreeScope(Document*);
130 virtual ~TreeScope();
131
132 void destroyTreeScopeData();
133 void clearDocumentScope();
setDocumentScope(Document * document)134 void setDocumentScope(Document* document)
135 {
136 ASSERT(document);
137 m_documentScope = document;
138 }
139
hasGuardRefCount()140 bool hasGuardRefCount() const { return m_guardRefCount; }
141
142 private:
143 TreeScope();
144
dispose()145 virtual void dispose() { }
146
147 int refCount() const;
148 #if SECURITY_ASSERT_ENABLED
149 bool deletionHasBegun();
150 void beginDeletion();
151 #else
deletionHasBegun()152 bool deletionHasBegun() { return false; }
beginDeletion()153 void beginDeletion() { }
154 #endif
155
156 bool rootNodeHasTreeSharedParent() const;
157
158 Node* m_rootNode;
159 Document* m_documentScope;
160 TreeScope* m_parentTreeScope;
161 int m_guardRefCount;
162
163 OwnPtr<DocumentOrderedMap> m_elementsById;
164 OwnPtr<DocumentOrderedMap> m_imageMapsByName;
165 OwnPtr<DocumentOrderedMap> m_labelsByForAttribute;
166
167 OwnPtr<IdTargetObserverRegistry> m_idTargetObserverRegistry;
168
169 mutable RefPtr<DOMSelection> m_selection;
170 };
171
hasElementWithId(StringImpl * id)172 inline bool TreeScope::hasElementWithId(StringImpl* id) const
173 {
174 ASSERT(id);
175 return m_elementsById && m_elementsById->contains(id);
176 }
177
containsMultipleElementsWithId(const AtomicString & id)178 inline bool TreeScope::containsMultipleElementsWithId(const AtomicString& id) const
179 {
180 return m_elementsById && m_elementsById->containsMultiple(id.impl());
181 }
182
183 inline bool operator==(const TreeScope& a, const TreeScope& b) { return &a == &b; }
184 inline bool operator==(const TreeScope& a, const TreeScope* b) { return &a == b; }
185 inline bool operator==(const TreeScope* a, const TreeScope& b) { return a == &b; }
186 inline bool operator!=(const TreeScope& a, const TreeScope& b) { return !(a == b); }
187 inline bool operator!=(const TreeScope& a, const TreeScope* b) { return !(a == b); }
188 inline bool operator!=(const TreeScope* a, const TreeScope& b) { return !(a == b); }
189
190 RenderObject* rendererFromPoint(Document*, int x, int y, LayoutPoint* localPoint = 0);
191 TreeScope* commonTreeScope(Node*, Node*);
192
193 } // namespace WebCore
194
195 #endif // TreeScope_h
196