1 /*
2 * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
3 * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010 Apple Inc. All right reserved.
4 * Copyright (C) 2010 Google 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
23 #ifndef InlineIterator_h
24 #define InlineIterator_h
25
26 #include "core/rendering/BidiRun.h"
27 #include "core/rendering/RenderBlockFlow.h"
28 #include "core/rendering/RenderInline.h"
29 #include "core/rendering/RenderText.h"
30 #include "wtf/StdLibExtras.h"
31
32 namespace blink {
33
34 // This class is used to RenderInline subtrees, stepping by character within the
35 // text children. InlineIterator will use bidiNext to find the next RenderText
36 // optionally notifying a BidiResolver every time it steps into/out of a RenderInline.
37 class InlineIterator {
38 public:
39 enum IncrementRule {
40 FastIncrementInIsolatedRenderer,
41 FastIncrementInTextNode
42 };
43
InlineIterator()44 InlineIterator()
45 : m_root(0)
46 , m_obj(0)
47 , m_nextBreakablePosition(-1)
48 , m_pos(0)
49 {
50 }
51
InlineIterator(RenderObject * root,RenderObject * o,unsigned p)52 InlineIterator(RenderObject* root, RenderObject* o, unsigned p)
53 : m_root(root)
54 , m_obj(o)
55 , m_nextBreakablePosition(-1)
56 , m_pos(p)
57 {
58 }
59
clear()60 void clear() { moveTo(0, 0); }
61
moveToStartOf(RenderObject * object)62 void moveToStartOf(RenderObject* object)
63 {
64 moveTo(object, 0);
65 }
66
67 void moveTo(RenderObject* object, unsigned offset, int nextBreak = -1)
68 {
69 m_obj = object;
70 m_pos = offset;
71 m_nextBreakablePosition = nextBreak;
72 }
73
object()74 RenderObject* object() const { return m_obj; }
setObject(RenderObject * object)75 void setObject(RenderObject* object) { m_obj = object; }
76
nextBreakablePosition()77 int nextBreakablePosition() const { return m_nextBreakablePosition; }
setNextBreakablePosition(int position)78 void setNextBreakablePosition(int position) { m_nextBreakablePosition = position; }
79
offset()80 unsigned offset() const { return m_pos; }
setOffset(unsigned position)81 void setOffset(unsigned position) { m_pos = position; }
root()82 RenderObject* root() const { return m_root; }
83
84 void fastIncrementInTextNode();
85 void increment(InlineBidiResolver* = 0, IncrementRule = FastIncrementInTextNode);
86 bool atEnd() const;
87
atTextParagraphSeparator()88 inline bool atTextParagraphSeparator() const
89 {
90 return m_obj && m_obj->preservesNewline() && m_obj->isText() && toRenderText(m_obj)->textLength()
91 && !toRenderText(m_obj)->isWordBreak() && toRenderText(m_obj)->characterAt(m_pos) == '\n';
92 }
93
atParagraphSeparator()94 inline bool atParagraphSeparator() const
95 {
96 return (m_obj && m_obj->isBR()) || atTextParagraphSeparator();
97 }
98
99 UChar characterAt(unsigned) const;
100 UChar current() const;
101 UChar previousInSameNode() const;
102 ALWAYS_INLINE WTF::Unicode::Direction direction() const;
103
104 private:
105 RenderObject* m_root;
106 RenderObject* m_obj;
107
108 int m_nextBreakablePosition;
109 unsigned m_pos;
110 };
111
112 inline bool operator==(const InlineIterator& it1, const InlineIterator& it2)
113 {
114 return it1.offset() == it2.offset() && it1.object() == it2.object();
115 }
116
117 inline bool operator!=(const InlineIterator& it1, const InlineIterator& it2)
118 {
119 return it1.offset() != it2.offset() || it1.object() != it2.object();
120 }
121
embedCharFromDirection(TextDirection dir,EUnicodeBidi unicodeBidi)122 static inline WTF::Unicode::Direction embedCharFromDirection(TextDirection dir, EUnicodeBidi unicodeBidi)
123 {
124 using namespace WTF::Unicode;
125 if (unicodeBidi == Embed)
126 return dir == RTL ? RightToLeftEmbedding : LeftToRightEmbedding;
127 return dir == RTL ? RightToLeftOverride : LeftToRightOverride;
128 }
129
130 template <class Observer>
notifyObserverEnteredObject(Observer * observer,RenderObject * object)131 static inline void notifyObserverEnteredObject(Observer* observer, RenderObject* object)
132 {
133 if (!observer || !object || !object->isRenderInline())
134 return;
135
136 RenderStyle* style = object->style();
137 EUnicodeBidi unicodeBidi = style->unicodeBidi();
138 if (unicodeBidi == UBNormal) {
139 // http://dev.w3.org/csswg/css3-writing-modes/#unicode-bidi
140 // "The element does not open an additional level of embedding with respect to the bidirectional algorithm."
141 // Thus we ignore any possible dir= attribute on the span.
142 return;
143 }
144 if (isIsolated(unicodeBidi)) {
145 // Make sure that explicit embeddings are committed before we enter the isolated content.
146 observer->commitExplicitEmbedding(observer->runs());
147 observer->enterIsolate();
148 // Embedding/Override characters implied by dir= will be handled when
149 // we process the isolated span, not when laying out the "parent" run.
150 return;
151 }
152
153 if (!observer->inIsolate())
154 observer->embed(embedCharFromDirection(style->direction(), unicodeBidi), FromStyleOrDOM);
155 }
156
157 template <class Observer>
notifyObserverWillExitObject(Observer * observer,RenderObject * object)158 static inline void notifyObserverWillExitObject(Observer* observer, RenderObject* object)
159 {
160 if (!observer || !object || !object->isRenderInline())
161 return;
162
163 EUnicodeBidi unicodeBidi = object->style()->unicodeBidi();
164 if (unicodeBidi == UBNormal)
165 return; // Nothing to do for unicode-bidi: normal
166 if (isIsolated(unicodeBidi)) {
167 observer->exitIsolate();
168 return;
169 }
170
171 // Otherwise we pop any embed/override character we added when we opened this tag.
172 if (!observer->inIsolate())
173 observer->embed(WTF::Unicode::PopDirectionalFormat, FromStyleOrDOM);
174 }
175
isIteratorTarget(RenderObject * object)176 static inline bool isIteratorTarget(RenderObject* object)
177 {
178 ASSERT(object); // The iterator will of course return 0, but its not an expected argument to this function.
179 return object->isText() || object->isFloating() || object->isOutOfFlowPositioned() || object->isReplaced();
180 }
181
182 // This enum is only used for bidiNextShared()
183 enum EmptyInlineBehavior {
184 SkipEmptyInlines,
185 IncludeEmptyInlines,
186 };
187
isEmptyInline(RenderObject * object)188 static bool isEmptyInline(RenderObject* object)
189 {
190 if (!object->isRenderInline())
191 return false;
192
193 for (RenderObject* curr = toRenderInline(object)->firstChild(); curr; curr = curr->nextSibling()) {
194 if (curr->isFloatingOrOutOfFlowPositioned())
195 continue;
196 if (curr->isText() && toRenderText(curr)->isAllCollapsibleWhitespace())
197 continue;
198
199 if (!isEmptyInline(curr))
200 return false;
201 }
202 return true;
203 }
204
205 // FIXME: This function is misleadingly named. It has little to do with bidi.
206 // This function will iterate over inlines within a block, optionally notifying
207 // a bidi resolver as it enters/exits inlines (so it can push/pop embedding levels).
208 template <class Observer>
209 static inline RenderObject* bidiNextShared(RenderObject* root, RenderObject* current, Observer* observer = 0, EmptyInlineBehavior emptyInlineBehavior = SkipEmptyInlines, bool* endOfInlinePtr = 0)
210 {
211 RenderObject* next = 0;
212 // oldEndOfInline denotes if when we last stopped iterating if we were at the end of an inline.
213 bool oldEndOfInline = endOfInlinePtr ? *endOfInlinePtr : false;
214 bool endOfInline = false;
215
216 while (current) {
217 next = 0;
218 if (!oldEndOfInline && !isIteratorTarget(current)) {
219 next = current->slowFirstChild();
220 notifyObserverEnteredObject(observer, next);
221 }
222
223 // We hit this when either current has no children, or when current is not a renderer we care about.
224 if (!next) {
225 // If it is a renderer we care about, and we're doing our inline-walk, return it.
226 if (emptyInlineBehavior == IncludeEmptyInlines && !oldEndOfInline && current->isRenderInline()) {
227 next = current;
228 endOfInline = true;
229 break;
230 }
231
232 while (current && current != root) {
233 notifyObserverWillExitObject(observer, current);
234
235 next = current->nextSibling();
236 if (next) {
237 notifyObserverEnteredObject(observer, next);
238 break;
239 }
240
241 current = current->parent();
242 if (emptyInlineBehavior == IncludeEmptyInlines && current && current != root && current->isRenderInline()) {
243 next = current;
244 endOfInline = true;
245 break;
246 }
247 }
248 }
249
250 if (!next)
251 break;
252
253 if (isIteratorTarget(next)
254 || ((emptyInlineBehavior == IncludeEmptyInlines || isEmptyInline(next)) // Always return EMPTY inlines.
255 && next->isRenderInline()))
256 break;
257 current = next;
258 }
259
260 if (endOfInlinePtr)
261 *endOfInlinePtr = endOfInline;
262
263 return next;
264 }
265
266 template <class Observer>
bidiNextSkippingEmptyInlines(RenderObject * root,RenderObject * current,Observer * observer)267 static inline RenderObject* bidiNextSkippingEmptyInlines(RenderObject* root, RenderObject* current, Observer* observer)
268 {
269 // The SkipEmptyInlines callers never care about endOfInlinePtr.
270 return bidiNextShared(root, current, observer, SkipEmptyInlines);
271 }
272
273 // This makes callers cleaner as they don't have to specify a type for the observer when not providing one.
bidiNextSkippingEmptyInlines(RenderObject * root,RenderObject * current)274 static inline RenderObject* bidiNextSkippingEmptyInlines(RenderObject* root, RenderObject* current)
275 {
276 InlineBidiResolver* observer = 0;
277 return bidiNextSkippingEmptyInlines(root, current, observer);
278 }
279
280 static inline RenderObject* bidiNextIncludingEmptyInlines(RenderObject* root, RenderObject* current, bool* endOfInlinePtr = 0)
281 {
282 InlineBidiResolver* observer = 0; // Callers who include empty inlines, never use an observer.
283 return bidiNextShared(root, current, observer, IncludeEmptyInlines, endOfInlinePtr);
284 }
285
286 static inline RenderObject* bidiFirstSkippingEmptyInlines(RenderBlockFlow* root, BidiRunList<BidiRun>& runs, InlineBidiResolver* resolver = 0)
287 {
288 RenderObject* o = root->firstChild();
289 if (!o)
290 return 0;
291
292 if (o->isRenderInline()) {
293 notifyObserverEnteredObject(resolver, o);
294 if (!isEmptyInline(o))
295 o = bidiNextSkippingEmptyInlines(root, o, resolver);
296 else {
297 // Never skip empty inlines.
298 if (resolver)
299 resolver->commitExplicitEmbedding(runs);
300 return o;
301 }
302 }
303
304 // FIXME: Unify this with the bidiNext call above.
305 if (o && !isIteratorTarget(o))
306 o = bidiNextSkippingEmptyInlines(root, o, resolver);
307
308 if (resolver)
309 resolver->commitExplicitEmbedding(runs);
310 return o;
311 }
312
313 // FIXME: This method needs to be renamed when bidiNext finds a good name.
bidiFirstIncludingEmptyInlines(RenderBlock * root)314 static inline RenderObject* bidiFirstIncludingEmptyInlines(RenderBlock* root)
315 {
316 RenderObject* o = root->firstChild();
317 // If either there are no children to walk, or the first one is correct
318 // then just return it.
319 if (!o || o->isRenderInline() || isIteratorTarget(o))
320 return o;
321
322 return bidiNextIncludingEmptyInlines(root, o);
323 }
324
fastIncrementInTextNode()325 inline void InlineIterator::fastIncrementInTextNode()
326 {
327 ASSERT(m_obj);
328 ASSERT(m_obj->isText());
329 ASSERT(m_pos <= toRenderText(m_obj)->textLength());
330 if (m_pos < INT_MAX)
331 m_pos++;
332 }
333
334 // FIXME: This is used by RenderBlockFlow for simplified layout, and has nothing to do with bidi
335 // it shouldn't use functions called bidiFirst and bidiNext.
336 class InlineWalker {
337 public:
InlineWalker(RenderBlock * root)338 InlineWalker(RenderBlock* root)
339 : m_root(root)
340 , m_current(0)
341 , m_atEndOfInline(false)
342 {
343 // FIXME: This class should be taught how to do the SkipEmptyInlines codepath as well.
344 m_current = bidiFirstIncludingEmptyInlines(m_root);
345 }
346
root()347 RenderBlock* root() { return m_root; }
current()348 RenderObject* current() { return m_current; }
349
atEndOfInline()350 bool atEndOfInline() { return m_atEndOfInline; }
atEnd()351 bool atEnd() const { return !m_current; }
352
advance()353 RenderObject* advance()
354 {
355 // FIXME: Support SkipEmptyInlines and observer parameters.
356 m_current = bidiNextIncludingEmptyInlines(m_root, m_current, &m_atEndOfInline);
357 return m_current;
358 }
359 private:
360 RenderBlock* m_root;
361 RenderObject* m_current;
362 bool m_atEndOfInline;
363 };
364
endOfLineHasIsolatedObjectAncestor(const InlineIterator & isolatedIterator,const InlineIterator & ancestorItertor)365 static inline bool endOfLineHasIsolatedObjectAncestor(const InlineIterator& isolatedIterator, const InlineIterator& ancestorItertor)
366 {
367 if (!isolatedIterator.object() || !isIsolated(isolatedIterator.object()->style()->unicodeBidi()))
368 return false;
369
370 RenderObject* innerIsolatedObject = isolatedIterator.object();
371 while (innerIsolatedObject && innerIsolatedObject != isolatedIterator.root()) {
372 if (innerIsolatedObject == ancestorItertor.object())
373 return true;
374 innerIsolatedObject = innerIsolatedObject->parent();
375 }
376 return false;
377 }
378
increment(InlineBidiResolver * resolver,IncrementRule rule)379 inline void InlineIterator::increment(InlineBidiResolver* resolver, IncrementRule rule)
380 {
381 if (!m_obj)
382 return;
383
384 if (rule == FastIncrementInIsolatedRenderer
385 && resolver && resolver->inIsolate()
386 && !endOfLineHasIsolatedObjectAncestor(resolver->endOfLine(), resolver->position())) {
387 moveTo(bidiNextSkippingEmptyInlines(m_root, m_obj, resolver), 0);
388 return;
389 }
390
391 if (m_obj->isText()) {
392 fastIncrementInTextNode();
393 if (m_pos < toRenderText(m_obj)->textLength())
394 return;
395 }
396 // bidiNext can return 0, so use moveTo instead of moveToStartOf
397 moveTo(bidiNextSkippingEmptyInlines(m_root, m_obj, resolver), 0);
398 }
399
atEnd()400 inline bool InlineIterator::atEnd() const
401 {
402 return !m_obj;
403 }
404
characterAt(unsigned index)405 inline UChar InlineIterator::characterAt(unsigned index) const
406 {
407 if (!m_obj || !m_obj->isText())
408 return 0;
409
410 return toRenderText(m_obj)->characterAt(index);
411 }
412
current()413 inline UChar InlineIterator::current() const
414 {
415 return characterAt(m_pos);
416 }
417
previousInSameNode()418 inline UChar InlineIterator::previousInSameNode() const
419 {
420 if (!m_pos)
421 return 0;
422
423 return characterAt(m_pos - 1);
424 }
425
direction()426 ALWAYS_INLINE WTF::Unicode::Direction InlineIterator::direction() const
427 {
428 if (UChar c = current())
429 return WTF::Unicode::direction(c);
430
431 if (m_obj && m_obj->isListMarker())
432 return m_obj->style()->isLeftToRightDirection() ? WTF::Unicode::LeftToRight : WTF::Unicode::RightToLeft;
433
434 return WTF::Unicode::OtherNeutral;
435 }
436
437 template<>
increment()438 inline void InlineBidiResolver::increment()
439 {
440 m_current.increment(this, InlineIterator::FastIncrementInIsolatedRenderer);
441 }
442
443 template <>
isEndOfLine(const InlineIterator & end)444 inline bool InlineBidiResolver::isEndOfLine(const InlineIterator& end)
445 {
446 bool inEndOfLine = m_current == end || m_current.atEnd() || (inIsolate() && m_current.object() == end.object());
447 if (inIsolate() && inEndOfLine) {
448 m_current.moveTo(m_current.object(), end.offset(), m_current.nextBreakablePosition());
449 m_last = m_current;
450 updateStatusLastFromCurrentDirection(WTF::Unicode::OtherNeutral);
451 }
452 return inEndOfLine;
453 }
454
isCollapsibleSpace(UChar character,RenderText * renderer)455 static inline bool isCollapsibleSpace(UChar character, RenderText* renderer)
456 {
457 if (character == ' ' || character == '\t' || character == softHyphen)
458 return true;
459 if (character == '\n')
460 return !renderer->style()->preserveNewline();
461 return false;
462 }
463
464 template <typename CharacterType>
findFirstTrailingSpace(RenderText * lastText,const CharacterType * characters,int start,int stop)465 static inline int findFirstTrailingSpace(RenderText* lastText, const CharacterType* characters, int start, int stop)
466 {
467 int firstSpace = stop;
468 while (firstSpace > start) {
469 UChar current = characters[firstSpace - 1];
470 if (!isCollapsibleSpace(current, lastText))
471 break;
472 firstSpace--;
473 }
474
475 return firstSpace;
476 }
477
478 template <>
findFirstTrailingSpaceAtRun(BidiRun * run)479 inline int InlineBidiResolver::findFirstTrailingSpaceAtRun(BidiRun* run)
480 {
481 ASSERT(run);
482 RenderObject* lastObject = run->m_object;
483 if (!lastObject->isText())
484 return run->m_stop;
485
486 RenderText* lastText = toRenderText(lastObject);
487 int firstSpace;
488 if (lastText->is8Bit())
489 firstSpace = findFirstTrailingSpace(lastText, lastText->characters8(), run->start(), run->stop());
490 else
491 firstSpace = findFirstTrailingSpace(lastText, lastText->characters16(), run->start(), run->stop());
492 return firstSpace;
493 }
494
495 template <>
addTrailingRun(BidiRunList<BidiRun> & runs,int start,int stop,BidiRun * run,BidiContext * context,TextDirection direction)496 inline BidiRun* InlineBidiResolver::addTrailingRun(BidiRunList<BidiRun>& runs, int start, int stop, BidiRun* run, BidiContext* context, TextDirection direction) const
497 {
498 BidiRun* newTrailingRun = new BidiRun(start, stop, run->m_object, context, WTF::Unicode::OtherNeutral);
499 if (direction == LTR)
500 runs.addRun(newTrailingRun);
501 else
502 runs.prependRun(newTrailingRun);
503
504 return newTrailingRun;
505 }
506
507 template <>
needsToApplyL1Rule(BidiRunList<BidiRun> & runs)508 inline bool InlineBidiResolver::needsToApplyL1Rule(BidiRunList<BidiRun>& runs)
509 {
510 if (!runs.logicallyLastRun()->m_object->style()->breakOnlyAfterWhiteSpace()
511 || !runs.logicallyLastRun()->m_object->style()->autoWrap())
512 return false;
513 return true;
514 }
515
isIsolatedInline(RenderObject * object)516 static inline bool isIsolatedInline(RenderObject* object)
517 {
518 ASSERT(object);
519 return object->isRenderInline() && isIsolated(object->style()->unicodeBidi());
520 }
521
highestContainingIsolateWithinRoot(RenderObject * object,RenderObject * root)522 static inline RenderObject* highestContainingIsolateWithinRoot(RenderObject* object, RenderObject* root)
523 {
524 ASSERT(object);
525 RenderObject* containingIsolateObj = 0;
526 while (object && object != root) {
527 if (isIsolatedInline(object))
528 containingIsolateObj = object;
529
530 object = object->parent();
531 }
532 return containingIsolateObj;
533 }
534
numberOfIsolateAncestors(const InlineIterator & iter)535 static inline unsigned numberOfIsolateAncestors(const InlineIterator& iter)
536 {
537 RenderObject* object = iter.object();
538 if (!object)
539 return 0;
540 unsigned count = 0;
541 while (object && object != iter.root()) {
542 if (isIsolatedInline(object))
543 count++;
544 object = object->parent();
545 }
546 return count;
547 }
548
549 // FIXME: This belongs on InlineBidiResolver, except it's a template specialization
550 // of BidiResolver which knows nothing about RenderObjects.
addPlaceholderRunForIsolatedInline(InlineBidiResolver & resolver,RenderObject * obj,unsigned pos)551 static inline BidiRun* addPlaceholderRunForIsolatedInline(InlineBidiResolver& resolver, RenderObject* obj, unsigned pos)
552 {
553 ASSERT(obj);
554 BidiRun* isolatedRun = new BidiRun(pos, pos, obj, resolver.context(), resolver.dir());
555 resolver.runs().addRun(isolatedRun);
556 // FIXME: isolatedRuns() could be a hash of object->run and then we could cheaply
557 // ASSERT here that we didn't create multiple objects for the same inline.
558 resolver.isolatedRuns().append(isolatedRun);
559 return isolatedRun;
560 }
561
createRun(int start,int end,RenderObject * obj,InlineBidiResolver & resolver)562 static inline BidiRun* createRun(int start, int end, RenderObject* obj, InlineBidiResolver& resolver)
563 {
564 return new BidiRun(start, end, obj, resolver.context(), resolver.dir());
565 }
566
567 enum AppendRunBehavior {
568 AppendingFakeRun,
569 AppendingRunsForObject
570 };
571
572 class IsolateTracker {
573 public:
IsolateTracker(BidiRunList<BidiRun> & runs,unsigned nestedIsolateCount)574 explicit IsolateTracker(BidiRunList<BidiRun>& runs, unsigned nestedIsolateCount)
575 : m_nestedIsolateCount(nestedIsolateCount)
576 , m_haveAddedFakeRunForRootIsolate(false)
577 , m_runs(runs)
578 {
579 }
580
setMidpointStateForRootIsolate(const LineMidpointState & midpointState)581 void setMidpointStateForRootIsolate(const LineMidpointState& midpointState)
582 {
583 m_midpointStateForRootIsolate = midpointState;
584 }
585
enterIsolate()586 void enterIsolate() { m_nestedIsolateCount++; }
exitIsolate()587 void exitIsolate()
588 {
589 ASSERT(m_nestedIsolateCount >= 1);
590 m_nestedIsolateCount--;
591 if (!inIsolate())
592 m_haveAddedFakeRunForRootIsolate = false;
593 }
inIsolate()594 bool inIsolate() const { return m_nestedIsolateCount; }
595
596 // We don't care if we encounter bidi directional overrides.
embed(WTF::Unicode::Direction,BidiEmbeddingSource)597 void embed(WTF::Unicode::Direction, BidiEmbeddingSource) { }
commitExplicitEmbedding(BidiRunList<BidiRun> &)598 void commitExplicitEmbedding(BidiRunList<BidiRun>&) { }
runs()599 BidiRunList<BidiRun>& runs() { return m_runs; }
600
addFakeRunIfNecessary(RenderObject * obj,unsigned pos,unsigned end,InlineBidiResolver & resolver)601 void addFakeRunIfNecessary(RenderObject* obj, unsigned pos, unsigned end, InlineBidiResolver& resolver)
602 {
603 // We only need to add a fake run for a given isolated span once during each call to createBidiRunsForLine.
604 // We'll be called for every span inside the isolated span so we just ignore subsequent calls.
605 // We also avoid creating a fake run until we hit a child that warrants one, e.g. we skip floats.
606 if (RenderBlockFlow::shouldSkipCreatingRunsForObject(obj))
607 return;
608 if (!m_haveAddedFakeRunForRootIsolate) {
609 BidiRun* run = addPlaceholderRunForIsolatedInline(resolver, obj, pos);
610 resolver.setMidpointStateForIsolatedRun(run, m_midpointStateForRootIsolate);
611 m_haveAddedFakeRunForRootIsolate = true;
612 }
613 // obj and pos together denote a single position in the inline, from which the parsing of the isolate will start.
614 // We don't need to mark the end of the run because this is implicit: it is either endOfLine or the end of the
615 // isolate, when we call createBidiRunsForLine it will stop at whichever comes first.
616 }
617
618 private:
619 unsigned m_nestedIsolateCount;
620 bool m_haveAddedFakeRunForRootIsolate;
621 LineMidpointState m_midpointStateForRootIsolate;
622 BidiRunList<BidiRun>& m_runs;
623 };
624
appendRunObjectIfNecessary(RenderObject * obj,unsigned start,unsigned end,InlineBidiResolver & resolver,AppendRunBehavior behavior,IsolateTracker & tracker)625 static void inline appendRunObjectIfNecessary(RenderObject* obj, unsigned start, unsigned end, InlineBidiResolver& resolver, AppendRunBehavior behavior, IsolateTracker& tracker)
626 {
627 if (behavior == AppendingFakeRun)
628 tracker.addFakeRunIfNecessary(obj, start, end, resolver);
629 else
630 resolver.runs().addRun(createRun(start, end, obj, resolver));
631 }
632
adjustMidpointsAndAppendRunsForObjectIfNeeded(RenderObject * obj,unsigned start,unsigned end,InlineBidiResolver & resolver,AppendRunBehavior behavior,IsolateTracker & tracker)633 static void adjustMidpointsAndAppendRunsForObjectIfNeeded(RenderObject* obj, unsigned start, unsigned end, InlineBidiResolver& resolver, AppendRunBehavior behavior, IsolateTracker& tracker)
634 {
635 if (start > end || RenderBlockFlow::shouldSkipCreatingRunsForObject(obj))
636 return;
637
638 LineMidpointState& lineMidpointState = resolver.midpointState();
639 bool haveNextMidpoint = (lineMidpointState.currentMidpoint() < lineMidpointState.numMidpoints());
640 InlineIterator nextMidpoint;
641 if (haveNextMidpoint)
642 nextMidpoint = lineMidpointState.midpoints()[lineMidpointState.currentMidpoint()];
643 if (lineMidpointState.betweenMidpoints()) {
644 if (!(haveNextMidpoint && nextMidpoint.object() == obj))
645 return;
646 // This is a new start point. Stop ignoring objects and
647 // adjust our start.
648 lineMidpointState.setBetweenMidpoints(false);
649 start = nextMidpoint.offset();
650 lineMidpointState.incrementCurrentMidpoint();
651 if (start < end)
652 return adjustMidpointsAndAppendRunsForObjectIfNeeded(obj, start, end, resolver, behavior, tracker);
653 } else {
654 if (!haveNextMidpoint || (obj != nextMidpoint.object())) {
655 appendRunObjectIfNecessary(obj, start, end, resolver, behavior, tracker);
656 return;
657 }
658
659 // An end midpoint has been encountered within our object. We
660 // need to go ahead and append a run with our endpoint.
661 if (nextMidpoint.offset() + 1 <= end) {
662 lineMidpointState.setBetweenMidpoints(true);
663 lineMidpointState.incrementCurrentMidpoint();
664 if (nextMidpoint.offset() != UINT_MAX) { // UINT_MAX means stop at the object and don't nclude any of it.
665 if (nextMidpoint.offset() + 1 > start)
666 appendRunObjectIfNecessary(obj, start, nextMidpoint.offset() + 1, resolver, behavior, tracker);
667 return adjustMidpointsAndAppendRunsForObjectIfNeeded(obj, nextMidpoint.offset() + 1, end, resolver, behavior, tracker);
668 }
669 } else {
670 appendRunObjectIfNecessary(obj, start, end, resolver, behavior, tracker);
671 }
672 }
673 }
674
addFakeRunIfNecessary(RenderObject * obj,unsigned start,unsigned end,InlineBidiResolver & resolver,IsolateTracker & tracker)675 static inline void addFakeRunIfNecessary(RenderObject* obj, unsigned start, unsigned end, InlineBidiResolver& resolver, IsolateTracker& tracker)
676 {
677 tracker.setMidpointStateForRootIsolate(resolver.midpointState());
678 adjustMidpointsAndAppendRunsForObjectIfNeeded(obj, start, obj->length(), resolver, AppendingFakeRun, tracker);
679 }
680
681 template <>
appendRun(BidiRunList<BidiRun> & runs)682 inline void InlineBidiResolver::appendRun(BidiRunList<BidiRun>& runs)
683 {
684 if (!m_emptyRun && !m_eor.atEnd() && !m_reachedEndOfLine) {
685 // Keep track of when we enter/leave "unicode-bidi: isolate" inlines.
686 // Initialize our state depending on if we're starting in the middle of such an inline.
687 // FIXME: Could this initialize from this->inIsolate() instead of walking up the render tree?
688 IsolateTracker isolateTracker(runs, numberOfIsolateAncestors(m_sor));
689 int start = m_sor.offset();
690 RenderObject* obj = m_sor.object();
691 while (obj && obj != m_eor.object() && obj != m_endOfRunAtEndOfLine.object()) {
692 if (isolateTracker.inIsolate())
693 addFakeRunIfNecessary(obj, start, obj->length(), *this, isolateTracker);
694 else
695 adjustMidpointsAndAppendRunsForObjectIfNeeded(obj, start, obj->length(), *this, AppendingRunsForObject, isolateTracker);
696 // FIXME: start/obj should be an InlineIterator instead of two separate variables.
697 start = 0;
698 obj = bidiNextSkippingEmptyInlines(m_sor.root(), obj, &isolateTracker);
699 }
700 bool isEndOfLine = obj == m_endOfLine.object() && !m_endOfLine.offset();
701 if (obj && !isEndOfLine) {
702 unsigned pos = obj == m_eor.object() ? m_eor.offset() : INT_MAX;
703 if (obj == m_endOfRunAtEndOfLine.object() && m_endOfRunAtEndOfLine.offset() <= pos) {
704 m_reachedEndOfLine = true;
705 pos = m_endOfRunAtEndOfLine.offset();
706 }
707 // It's OK to add runs for zero-length RenderObjects, just don't make the run larger than it should be
708 int end = obj->length() ? pos + 1 : 0;
709 if (isolateTracker.inIsolate())
710 addFakeRunIfNecessary(obj, start, end, *this, isolateTracker);
711 else
712 adjustMidpointsAndAppendRunsForObjectIfNeeded(obj, start, end, *this, AppendingRunsForObject, isolateTracker);
713 }
714
715 if (isEndOfLine)
716 m_reachedEndOfLine = true;
717 // If isolateTrack is inIsolate, the next |start of run| can not be the current isolated renderer.
718 if (isolateTracker.inIsolate())
719 m_eor.moveTo(bidiNextSkippingEmptyInlines(m_eor.root(), m_eor.object()), 0);
720 else
721 m_eor.increment();
722 m_sor = m_eor;
723 }
724
725 m_direction = WTF::Unicode::OtherNeutral;
726 m_status.eor = WTF::Unicode::OtherNeutral;
727 }
728
729 }
730
731 #endif // InlineIterator_h
732