1/*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
4 *           (C) 2001 Dirk Mueller (mueller@kde.org)
5 * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public License
18 * along with this library; see the file COPYING.LIB.  If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 *
22 */
23
24#ifndef ContainerNode_h
25#define ContainerNode_h
26
27#include "ExceptionCodePlaceholder.h"
28#include "Node.h"
29
30#include <wtf/OwnPtr.h>
31#include <wtf/Vector.h>
32
33namespace WebCore {
34
35class FloatPoint;
36
37typedef void (*NodeCallback)(Node*, unsigned);
38
39namespace Private {
40    template<class GenericNode, class GenericNodeContainer>
41    void addChildNodesToDeletionQueue(GenericNode*& head, GenericNode*& tail, GenericNodeContainer*);
42};
43
44class NoEventDispatchAssertion {
45public:
46    NoEventDispatchAssertion()
47    {
48#ifndef NDEBUG
49        if (!isMainThread())
50            return;
51        s_count++;
52#endif
53    }
54
55    ~NoEventDispatchAssertion()
56    {
57#ifndef NDEBUG
58        if (!isMainThread())
59            return;
60        ASSERT(s_count);
61        s_count--;
62#endif
63    }
64
65#ifndef NDEBUG
66    static bool isEventDispatchForbidden()
67    {
68        if (!isMainThread())
69            return false;
70        return s_count;
71    }
72#endif
73
74private:
75#ifndef NDEBUG
76    static unsigned s_count;
77#endif
78};
79
80class ContainerNode : public Node {
81    friend class PostAttachCallbackDisabler;
82public:
83    virtual ~ContainerNode();
84
85    Node* firstChild() const { return m_firstChild; }
86    Node* lastChild() const { return m_lastChild; }
87    bool hasChildNodes() const { return m_firstChild; }
88
89    unsigned childNodeCount() const;
90    Node* childNode(unsigned index) const;
91
92    bool insertBefore(PassRefPtr<Node> newChild, Node* refChild, ExceptionCode& = ASSERT_NO_EXCEPTION, AttachBehavior = AttachNow);
93    bool replaceChild(PassRefPtr<Node> newChild, Node* oldChild, ExceptionCode& = ASSERT_NO_EXCEPTION, AttachBehavior = AttachNow);
94    bool removeChild(Node* child, ExceptionCode& = ASSERT_NO_EXCEPTION);
95    bool appendChild(PassRefPtr<Node> newChild, ExceptionCode& = ASSERT_NO_EXCEPTION, AttachBehavior = AttachNow);
96
97    // These methods are only used during parsing.
98    // They don't send DOM mutation events or handle reparenting.
99    // However, arbitrary code may be run by beforeload handlers.
100    void parserAppendChild(PassRefPtr<Node>);
101    void parserRemoveChild(Node*);
102    void parserInsertBefore(PassRefPtr<Node> newChild, Node* refChild);
103
104    void removeChildren();
105    void takeAllChildrenFrom(ContainerNode*);
106
107    void cloneChildNodes(ContainerNode* clone);
108
109    virtual void attach(const AttachContext& = AttachContext()) OVERRIDE;
110    virtual void detach(const AttachContext& = AttachContext()) OVERRIDE;
111    virtual LayoutRect boundingBox() const OVERRIDE;
112    virtual void scheduleSetNeedsStyleRecalc(StyleChangeType = FullStyleChange) OVERRIDE FINAL;
113
114    // -----------------------------------------------------------------------------
115    // Notification of document structure changes (see Node.h for more notification methods)
116
117    // Notifies the node that it's list of children have changed (either by adding or removing child nodes), or a child
118    // node that is of the type CDATA_SECTION_NODE, TEXT_NODE or COMMENT_NODE has changed its value.
119    virtual void childrenChanged(bool createdByParser = false, Node* beforeChange = 0, Node* afterChange = 0, int childCountDelta = 0);
120
121    void attachChildren();
122    void attachChildrenLazily();
123    void detachChildren();
124    void detachChildrenIfNeeded();
125
126    void disconnectDescendantFrames();
127
128    virtual bool childShouldCreateRenderer(const NodeRenderingContext&) const { return true; }
129
130protected:
131    ContainerNode(Document*, ConstructionType = CreateContainer);
132
133    static void queuePostAttachCallback(NodeCallback, Node*, unsigned = 0);
134    static bool postAttachCallbacksAreSuspended();
135
136    template<class GenericNode, class GenericNodeContainer>
137    friend void appendChildToContainer(GenericNode* child, GenericNodeContainer*);
138
139    template<class GenericNode, class GenericNodeContainer>
140    friend void Private::addChildNodesToDeletionQueue(GenericNode*& head, GenericNode*& tail, GenericNodeContainer*);
141
142    void removeDetachedChildren();
143    void setFirstChild(Node* child) { m_firstChild = child; }
144    void setLastChild(Node* child) { m_lastChild = child; }
145
146private:
147    void removeBetween(Node* previousChild, Node* nextChild, Node* oldChild);
148    void insertBeforeCommon(Node* nextChild, Node* oldChild);
149
150    static void dispatchPostAttachCallbacks();
151    void suspendPostAttachCallbacks();
152    void resumePostAttachCallbacks();
153
154    bool getUpperLeftCorner(FloatPoint&) const;
155    bool getLowerRightCorner(FloatPoint&) const;
156
157    Node* m_firstChild;
158    Node* m_lastChild;
159};
160
161#ifndef NDEBUG
162bool childAttachedAllowedWhenAttachingChildren(ContainerNode*);
163#endif
164
165inline ContainerNode* toContainerNode(Node* node)
166{
167    ASSERT_WITH_SECURITY_IMPLICATION(!node || node->isContainerNode());
168    return static_cast<ContainerNode*>(node);
169}
170
171inline const ContainerNode* toContainerNode(const Node* node)
172{
173    ASSERT_WITH_SECURITY_IMPLICATION(!node || node->isContainerNode());
174    return static_cast<const ContainerNode*>(node);
175}
176
177// This will catch anyone doing an unnecessary cast.
178void toContainerNode(const ContainerNode*);
179
180inline ContainerNode::ContainerNode(Document* document, ConstructionType type)
181    : Node(document, type)
182    , m_firstChild(0)
183    , m_lastChild(0)
184{
185}
186
187inline void ContainerNode::attachChildren()
188{
189    for (Node* child = firstChild(); child; child = child->nextSibling()) {
190        ASSERT(!child->attached() || childAttachedAllowedWhenAttachingChildren(this));
191        if (!child->attached())
192            child->attach();
193    }
194}
195
196inline void ContainerNode::attachChildrenLazily()
197{
198    for (Node* child = firstChild(); child; child = child->nextSibling())
199        if (!child->attached())
200            child->lazyAttach();
201}
202
203inline void ContainerNode::detachChildrenIfNeeded()
204{
205    for (Node* child = firstChild(); child; child = child->nextSibling()) {
206        if (child->attached())
207            child->detach();
208    }
209}
210
211inline void ContainerNode::detachChildren()
212{
213    for (Node* child = firstChild(); child; child = child->nextSibling())
214        child->detach();
215}
216
217inline unsigned Node::childNodeCount() const
218{
219    if (!isContainerNode())
220        return 0;
221    return toContainerNode(this)->childNodeCount();
222}
223
224inline Node* Node::childNode(unsigned index) const
225{
226    if (!isContainerNode())
227        return 0;
228    return toContainerNode(this)->childNode(index);
229}
230
231inline Node* Node::firstChild() const
232{
233    if (!isContainerNode())
234        return 0;
235    return toContainerNode(this)->firstChild();
236}
237
238inline Node* Node::lastChild() const
239{
240    if (!isContainerNode())
241        return 0;
242    return toContainerNode(this)->lastChild();
243}
244
245inline Node* Node::highestAncestor() const
246{
247    Node* node = const_cast<Node*>(this);
248    Node* highest = node;
249    for (; node; node = node->parentNode())
250        highest = node;
251    return highest;
252}
253
254inline bool Node::needsShadowTreeWalker() const
255{
256    if (getFlag(NeedsShadowTreeWalkerFlag))
257        return true;
258    ContainerNode* parent = parentOrShadowHostNode();
259    return parent && parent->getFlag(NeedsShadowTreeWalkerFlag);
260}
261
262inline bool Node::isTreeScope() const
263{
264    return treeScope()->rootNode() == this;
265}
266
267// This constant controls how much buffer is initially allocated
268// for a Node Vector that is used to store child Nodes of a given Node.
269// FIXME: Optimize the value.
270const int initialNodeVectorSize = 11;
271typedef Vector<RefPtr<Node>, initialNodeVectorSize> NodeVector;
272
273inline void getChildNodes(Node* node, NodeVector& nodes)
274{
275    ASSERT(!nodes.size());
276    for (Node* child = node->firstChild(); child; child = child->nextSibling())
277        nodes.append(child);
278}
279
280class ChildNodesLazySnapshot {
281    WTF_MAKE_NONCOPYABLE(ChildNodesLazySnapshot);
282    WTF_MAKE_FAST_ALLOCATED;
283public:
284    explicit ChildNodesLazySnapshot(Node* parentNode)
285        : m_currentNode(parentNode->firstChild())
286        , m_currentIndex(0)
287    {
288        m_nextSnapshot = latestSnapshot;
289        latestSnapshot = this;
290    }
291
292    ~ChildNodesLazySnapshot()
293    {
294        latestSnapshot = m_nextSnapshot;
295    }
296
297    // Returns 0 if there is no next Node.
298    PassRefPtr<Node> nextNode()
299    {
300        if (LIKELY(!hasSnapshot())) {
301            RefPtr<Node> node = m_currentNode;
302            if (node)
303                m_currentNode = node->nextSibling();
304            return node.release();
305        }
306        Vector<RefPtr<Node> >& nodeVector = *m_childNodes;
307        if (m_currentIndex >= nodeVector.size())
308            return 0;
309        return nodeVector[m_currentIndex++];
310    }
311
312    void takeSnapshot()
313    {
314        if (hasSnapshot())
315            return;
316        m_childNodes = adoptPtr(new Vector<RefPtr<Node> >());
317        Node* node = m_currentNode.get();
318        while (node) {
319            m_childNodes->append(node);
320            node = node->nextSibling();
321        }
322    }
323
324    ChildNodesLazySnapshot* nextSnapshot() { return m_nextSnapshot; }
325    bool hasSnapshot() { return !!m_childNodes.get(); }
326
327    static void takeChildNodesLazySnapshot()
328    {
329        ChildNodesLazySnapshot* snapshot = latestSnapshot;
330        while (snapshot && !snapshot->hasSnapshot()) {
331            snapshot->takeSnapshot();
332            snapshot = snapshot->nextSnapshot();
333        }
334    }
335
336private:
337    static ChildNodesLazySnapshot* latestSnapshot;
338
339    RefPtr<Node> m_currentNode;
340    unsigned m_currentIndex;
341    OwnPtr<Vector<RefPtr<Node> > > m_childNodes; // Lazily instantiated.
342    ChildNodesLazySnapshot* m_nextSnapshot;
343};
344
345class PostAttachCallbackDisabler {
346public:
347    PostAttachCallbackDisabler(ContainerNode* node)
348        : m_node(node)
349    {
350        ASSERT(m_node);
351        m_node->suspendPostAttachCallbacks();
352    }
353
354    ~PostAttachCallbackDisabler()
355    {
356        m_node->resumePostAttachCallbacks();
357    }
358
359private:
360    ContainerNode* m_node;
361};
362
363} // namespace WebCore
364
365#endif // ContainerNode_h
366