1 /*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 * (C) 1999 Antti Koivisto (koivisto@kde.org)
4 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB. If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 */
21
22 #include "config.h"
23 #include "core/dom/Text.h"
24
25 #include "bindings/v8/ExceptionState.h"
26 #include "bindings/v8/ExceptionStatePlaceholder.h"
27 #include "core/SVGNames.h"
28 #include "core/css/resolver/StyleResolver.h"
29 #include "core/dom/ExceptionCode.h"
30 #include "core/dom/NodeRenderStyle.h"
31 #include "core/dom/NodeRenderingTraversal.h"
32 #include "core/dom/NodeTraversal.h"
33 #include "core/dom/RenderTreeBuilder.h"
34 #include "core/dom/shadow/ShadowRoot.h"
35 #include "core/events/ScopedEventQueue.h"
36 #include "core/rendering/RenderCombineText.h"
37 #include "core/rendering/RenderText.h"
38 #include "core/rendering/svg/RenderSVGInlineText.h"
39 #include "core/svg/SVGForeignObjectElement.h"
40 #include "wtf/text/CString.h"
41 #include "wtf/text/StringBuilder.h"
42
43 namespace WebCore {
44
create(Document & document,const String & data)45 PassRefPtrWillBeRawPtr<Text> Text::create(Document& document, const String& data)
46 {
47 return adoptRefWillBeNoop(new Text(document, data, CreateText));
48 }
49
createEditingText(Document & document,const String & data)50 PassRefPtrWillBeRawPtr<Text> Text::createEditingText(Document& document, const String& data)
51 {
52 return adoptRefWillBeNoop(new Text(document, data, CreateEditingText));
53 }
54
mergeNextSiblingNodesIfPossible()55 PassRefPtrWillBeRawPtr<Node> Text::mergeNextSiblingNodesIfPossible()
56 {
57 RefPtrWillBeRawPtr<Node> protect(this);
58
59 // Remove empty text nodes.
60 if (!length()) {
61 // Care must be taken to get the next node before removing the current node.
62 RefPtrWillBeRawPtr<Node> nextNode(NodeTraversal::nextPostOrder(*this));
63 remove(IGNORE_EXCEPTION);
64 return nextNode.release();
65 }
66
67 // Merge text nodes.
68 while (Node* nextSibling = this->nextSibling()) {
69 if (nextSibling->nodeType() != TEXT_NODE)
70 break;
71
72 RefPtrWillBeRawPtr<Text> nextText = toText(nextSibling);
73
74 // Remove empty text nodes.
75 if (!nextText->length()) {
76 nextText->remove(IGNORE_EXCEPTION);
77 continue;
78 }
79
80 // Both non-empty text nodes. Merge them.
81 unsigned offset = length();
82 String nextTextData = nextText->data();
83 String oldTextData = data();
84 setDataWithoutUpdate(data() + nextTextData);
85 updateTextRenderer(oldTextData.length(), 0);
86
87 // Empty nextText for layout update.
88 nextText->setDataWithoutUpdate(emptyString());
89 nextText->updateTextRenderer(0, nextTextData.length());
90
91 document().didMergeTextNodes(*nextText, offset);
92
93 // Restore nextText for mutation event.
94 nextText->setDataWithoutUpdate(nextTextData);
95 nextText->updateTextRenderer(0, 0);
96
97 document().incDOMTreeVersion();
98 didModifyData(oldTextData);
99 nextText->remove(IGNORE_EXCEPTION);
100 }
101
102 return NodeTraversal::nextPostOrder(*this);
103 }
104
splitText(unsigned offset,ExceptionState & exceptionState)105 PassRefPtrWillBeRawPtr<Text> Text::splitText(unsigned offset, ExceptionState& exceptionState)
106 {
107 // IndexSizeError: Raised if the specified offset is negative or greater than
108 // the number of 16-bit units in data.
109 if (offset > length()) {
110 exceptionState.throwDOMException(IndexSizeError, "The offset " + String::number(offset) + " is larger than the Text node's length.");
111 return nullptr;
112 }
113
114 EventQueueScope scope;
115 String oldStr = data();
116 RefPtrWillBeRawPtr<Text> newText = cloneWithData(oldStr.substring(offset));
117 setDataWithoutUpdate(oldStr.substring(0, offset));
118
119 didModifyData(oldStr);
120
121 if (parentNode())
122 parentNode()->insertBefore(newText.get(), nextSibling(), exceptionState);
123 if (exceptionState.hadException())
124 return nullptr;
125
126 if (renderer())
127 toRenderText(renderer())->setTextWithOffset(dataImpl(), 0, oldStr.length());
128
129 if (parentNode())
130 document().didSplitTextNode(*this);
131
132 return newText.release();
133 }
134
earliestLogicallyAdjacentTextNode(const Text * t)135 static const Text* earliestLogicallyAdjacentTextNode(const Text* t)
136 {
137 const Node* n = t;
138 while ((n = n->previousSibling())) {
139 Node::NodeType type = n->nodeType();
140 if (type == Node::TEXT_NODE || type == Node::CDATA_SECTION_NODE) {
141 t = toText(n);
142 continue;
143 }
144
145 break;
146 }
147 return t;
148 }
149
latestLogicallyAdjacentTextNode(const Text * t)150 static const Text* latestLogicallyAdjacentTextNode(const Text* t)
151 {
152 const Node* n = t;
153 while ((n = n->nextSibling())) {
154 Node::NodeType type = n->nodeType();
155 if (type == Node::TEXT_NODE || type == Node::CDATA_SECTION_NODE) {
156 t = toText(n);
157 continue;
158 }
159
160 break;
161 }
162 return t;
163 }
164
wholeText() const165 String Text::wholeText() const
166 {
167 const Text* startText = earliestLogicallyAdjacentTextNode(this);
168 const Text* endText = latestLogicallyAdjacentTextNode(this);
169
170 Node* onePastEndText = endText->nextSibling();
171 unsigned resultLength = 0;
172 for (const Node* n = startText; n != onePastEndText; n = n->nextSibling()) {
173 if (!n->isTextNode())
174 continue;
175 const String& data = toText(n)->data();
176 if (std::numeric_limits<unsigned>::max() - data.length() < resultLength)
177 CRASH();
178 resultLength += data.length();
179 }
180 StringBuilder result;
181 result.reserveCapacity(resultLength);
182 for (const Node* n = startText; n != onePastEndText; n = n->nextSibling()) {
183 if (!n->isTextNode())
184 continue;
185 result.append(toText(n)->data());
186 }
187 ASSERT(result.length() == resultLength);
188
189 return result.toString();
190 }
191
replaceWholeText(const String & newText)192 PassRefPtrWillBeRawPtr<Text> Text::replaceWholeText(const String& newText)
193 {
194 // Remove all adjacent text nodes, and replace the contents of this one.
195
196 // Protect startText and endText against mutation event handlers removing the last ref
197 RefPtrWillBeRawPtr<Text> startText = const_cast<Text*>(earliestLogicallyAdjacentTextNode(this));
198 RefPtrWillBeRawPtr<Text> endText = const_cast<Text*>(latestLogicallyAdjacentTextNode(this));
199
200 RefPtrWillBeRawPtr<Text> protectedThis(this); // Mutation event handlers could cause our last ref to go away
201 RefPtrWillBeRawPtr<ContainerNode> parent = parentNode(); // Protect against mutation handlers moving this node during traversal
202 for (RefPtrWillBeRawPtr<Node> n = startText; n && n != this && n->isTextNode() && n->parentNode() == parent;) {
203 RefPtrWillBeRawPtr<Node> nodeToRemove(n.release());
204 n = nodeToRemove->nextSibling();
205 parent->removeChild(nodeToRemove.get(), IGNORE_EXCEPTION);
206 }
207
208 if (this != endText) {
209 Node* onePastEndText = endText->nextSibling();
210 for (RefPtrWillBeRawPtr<Node> n = nextSibling(); n && n != onePastEndText && n->isTextNode() && n->parentNode() == parent;) {
211 RefPtrWillBeRawPtr<Node> nodeToRemove(n.release());
212 n = nodeToRemove->nextSibling();
213 parent->removeChild(nodeToRemove.get(), IGNORE_EXCEPTION);
214 }
215 }
216
217 if (newText.isEmpty()) {
218 if (parent && parentNode() == parent)
219 parent->removeChild(this, IGNORE_EXCEPTION);
220 return nullptr;
221 }
222
223 setData(newText);
224 return protectedThis.release();
225 }
226
nodeName() const227 String Text::nodeName() const
228 {
229 return "#text";
230 }
231
nodeType() const232 Node::NodeType Text::nodeType() const
233 {
234 return TEXT_NODE;
235 }
236
cloneNode(bool)237 PassRefPtrWillBeRawPtr<Node> Text::cloneNode(bool /*deep*/)
238 {
239 return cloneWithData(data());
240 }
241
textRendererIsNeeded(const RenderStyle & style,const RenderObject & parent)242 bool Text::textRendererIsNeeded(const RenderStyle& style, const RenderObject& parent)
243 {
244 if (isEditingText())
245 return true;
246
247 if (!length())
248 return false;
249
250 if (style.display() == NONE)
251 return false;
252
253 if (!containsOnlyWhitespace())
254 return true;
255
256 if (!parent.canHaveWhitespaceChildren())
257 return false;
258
259 if (style.preserveNewline()) // pre/pre-wrap/pre-line always make renderers.
260 return true;
261
262 const RenderObject* prev = NodeRenderingTraversal::previousSiblingRenderer(this);
263 if (prev && prev->isBR()) // <span><br/> <br/></span>
264 return false;
265
266 if (parent.isRenderInline()) {
267 // <span><div/> <div/></span>
268 if (prev && !prev->isInline())
269 return false;
270 } else {
271 if (parent.isRenderBlock() && !parent.childrenInline() && (!prev || !prev->isInline()))
272 return false;
273
274 // Avoiding creation of a Renderer for the text node is a non-essential memory optimization.
275 // So to avoid blowing up on very wide DOMs, we limit the number of siblings to visit.
276 unsigned maxSiblingsToVisit = 50;
277
278 RenderObject* first = parent.slowFirstChild();
279 while (first && first->isFloatingOrOutOfFlowPositioned() && maxSiblingsToVisit--)
280 first = first->nextSibling();
281 if (!first || NodeRenderingTraversal::nextSiblingRenderer(this) == first)
282 // Whitespace at the start of a block just goes away. Don't even
283 // make a render object for this text.
284 return false;
285 }
286 return true;
287 }
288
isSVGText(Text * text)289 static bool isSVGText(Text* text)
290 {
291 Node* parentOrShadowHostNode = text->parentOrShadowHostNode();
292 ASSERT(parentOrShadowHostNode);
293 return parentOrShadowHostNode->isSVGElement() && !isSVGForeignObjectElement(*parentOrShadowHostNode);
294 }
295
createTextRenderer(RenderStyle * style)296 RenderText* Text::createTextRenderer(RenderStyle* style)
297 {
298 if (isSVGText(this))
299 return new RenderSVGInlineText(this, dataImpl());
300
301 if (style->hasTextCombine())
302 return new RenderCombineText(this, dataImpl());
303
304 return new RenderText(this, dataImpl());
305 }
306
attach(const AttachContext & context)307 void Text::attach(const AttachContext& context)
308 {
309 RenderTreeBuilder(this, context.resolvedStyle).createRendererForTextIfNeeded();
310 CharacterData::attach(context);
311 }
312
recalcTextStyle(StyleRecalcChange change,Text * nextTextSibling)313 void Text::recalcTextStyle(StyleRecalcChange change, Text* nextTextSibling)
314 {
315 if (RenderText* renderer = toRenderText(this->renderer())) {
316 if (change != NoChange || needsStyleRecalc())
317 renderer->setStyle(document().ensureStyleResolver().styleForText(this));
318 if (needsStyleRecalc())
319 renderer->setText(dataImpl());
320 clearNeedsStyleRecalc();
321 } else if (needsStyleRecalc() || needsWhitespaceRenderer()) {
322 reattach();
323 reattachWhitespaceSiblings(nextTextSibling);
324 }
325 }
326
327 // If a whitespace node had no renderer and goes through a recalcStyle it may
328 // need to create one if the parent style now has white-space: pre.
needsWhitespaceRenderer()329 bool Text::needsWhitespaceRenderer()
330 {
331 ASSERT(!renderer());
332 if (RenderStyle* style = parentRenderStyle())
333 return style->preserveNewline();
334 return false;
335 }
336
updateTextRenderer(unsigned offsetOfReplacedData,unsigned lengthOfReplacedData,RecalcStyleBehavior recalcStyleBehavior)337 void Text::updateTextRenderer(unsigned offsetOfReplacedData, unsigned lengthOfReplacedData, RecalcStyleBehavior recalcStyleBehavior)
338 {
339 if (!inActiveDocument())
340 return;
341 RenderText* textRenderer = toRenderText(renderer());
342 if (!textRenderer || !textRendererIsNeeded(*textRenderer->style(), *textRenderer->parent())) {
343 lazyReattachIfAttached();
344 // FIXME: Editing should be updated so this is not neccesary.
345 if (recalcStyleBehavior == DeprecatedRecalcStyleImmediatlelyForEditing)
346 document().updateRenderTreeIfNeeded();
347 return;
348 }
349 textRenderer->setTextWithOffset(dataImpl(), offsetOfReplacedData, lengthOfReplacedData);
350 }
351
cloneWithData(const String & data)352 PassRefPtrWillBeRawPtr<Text> Text::cloneWithData(const String& data)
353 {
354 return create(document(), data);
355 }
356
357 #ifndef NDEBUG
formatForDebugger(char * buffer,unsigned length) const358 void Text::formatForDebugger(char *buffer, unsigned length) const
359 {
360 StringBuilder result;
361 String s;
362
363 result.append(nodeName());
364
365 s = data();
366 if (s.length() > 0) {
367 if (result.length())
368 result.appendLiteral("; ");
369 result.appendLiteral("value=");
370 result.append(s);
371 }
372
373 strncpy(buffer, result.toString().utf8().data(), length - 1);
374 }
375 #endif
376
377 } // namespace WebCore
378