2011-05-24 Nate Chapin <japhet@chromium.org>
[WebKit-https.git] / Source / WebCore / css / CSSFontSelector.cpp
1 /*
2  * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
3  *           (C) 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
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 COMPUTER, 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 COMPUTER, INC. OR
18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
25  */
26
27 #include "config.h"
28 #include "CSSFontSelector.h"
29
30 #include "CachedFont.h"
31 #include "CSSFontFace.h"
32 #include "CSSFontFaceRule.h"
33 #include "CSSFontFaceSource.h"
34 #include "CSSFontFaceSrcValue.h"
35 #include "CSSMutableStyleDeclaration.h"
36 #include "CSSPrimitiveValue.h"
37 #include "CSSPropertyNames.h"
38 #include "CSSSegmentedFontFace.h"
39 #include "CSSUnicodeRangeValue.h"
40 #include "CSSValueKeywords.h"
41 #include "CSSValueList.h"
42 #include "CachedResourceLoader.h"
43 #include "Document.h"
44 #include "FontCache.h"
45 #include "FontFamilyValue.h"
46 #include "Frame.h"
47 #include "RenderObject.h"
48 #include "Settings.h"
49 #include "SimpleFontData.h"
50 #include <wtf/text/AtomicString.h>
51
52 #if ENABLE(SVG)
53 #include "SVGFontFaceElement.h"
54 #include "SVGNames.h"
55 #endif
56
57 namespace WebCore {
58
59 CSSFontSelector::CSSFontSelector(Document* document)
60     : m_document(document)
61 {
62     // FIXME: An old comment used to say there was no need to hold a reference to m_document
63     // because "we are guaranteed to be destroyed before the document". But there does not
64     // seem to be any such guarantee.
65
66     ASSERT(m_document);
67     fontCache()->addClient(this);
68 }
69
70 CSSFontSelector::~CSSFontSelector()
71 {
72     fontCache()->removeClient(this);
73     deleteAllValues(m_fontFaces);
74     deleteAllValues(m_locallyInstalledFontFaces);
75     deleteAllValues(m_fonts);
76 }
77
78 bool CSSFontSelector::isEmpty() const
79 {
80     return m_fonts.isEmpty();
81 }
82
83 CachedResourceLoader* CSSFontSelector::cachedResourceLoader() const
84 {
85     return m_document ? m_document->cachedResourceLoader() : 0;
86 }
87
88 void CSSFontSelector::addFontFaceRule(const CSSFontFaceRule* fontFaceRule)
89 {
90     // Obtain the font-family property and the src property.  Both must be defined.
91     const CSSMutableStyleDeclaration* style = fontFaceRule->style();
92     RefPtr<CSSValue> fontFamily = style->getPropertyCSSValue(CSSPropertyFontFamily);
93     RefPtr<CSSValue> src = style->getPropertyCSSValue(CSSPropertySrc);
94     RefPtr<CSSValue> unicodeRange = style->getPropertyCSSValue(CSSPropertyUnicodeRange);
95     if (!fontFamily || !src || !fontFamily->isValueList() || !src->isValueList() || (unicodeRange && !unicodeRange->isValueList()))
96         return;
97
98     CSSValueList* familyList = static_cast<CSSValueList*>(fontFamily.get());
99     if (!familyList->length())
100         return;
101
102     CSSValueList* srcList = static_cast<CSSValueList*>(src.get());
103     if (!srcList->length())
104         return;
105
106     CSSValueList* rangeList = static_cast<CSSValueList*>(unicodeRange.get());
107
108     unsigned traitsMask = 0;
109
110     if (RefPtr<CSSValue> fontStyle = style->getPropertyCSSValue(CSSPropertyFontStyle)) {
111         if (fontStyle->isPrimitiveValue()) {
112             RefPtr<CSSValueList> list = CSSValueList::createCommaSeparated();
113             list->append(fontStyle);
114             fontStyle = list;
115         } else if (!fontStyle->isValueList())
116             return;
117
118         CSSValueList* styleList = static_cast<CSSValueList*>(fontStyle.get());
119         unsigned numStyles = styleList->length();
120         if (!numStyles)
121             return;
122
123         for (unsigned i = 0; i < numStyles; ++i) {
124             switch (static_cast<CSSPrimitiveValue*>(styleList->itemWithoutBoundsCheck(i))->getIdent()) {
125                 case CSSValueAll:
126                     traitsMask |= FontStyleMask;
127                     break;
128                 case CSSValueNormal:
129                     traitsMask |= FontStyleNormalMask;
130                     break;
131                 case CSSValueItalic:
132                 case CSSValueOblique:
133                     traitsMask |= FontStyleItalicMask;
134                     break;
135                 default:
136                     break;
137             }
138         }
139     } else
140         traitsMask |= FontStyleMask;
141
142     if (RefPtr<CSSValue> fontWeight = style->getPropertyCSSValue(CSSPropertyFontWeight)) {
143         if (fontWeight->isPrimitiveValue()) {
144             RefPtr<CSSValueList> list = CSSValueList::createCommaSeparated();
145             list->append(fontWeight);
146             fontWeight = list;
147         } else if (!fontWeight->isValueList())
148             return;
149
150         CSSValueList* weightList = static_cast<CSSValueList*>(fontWeight.get());
151         unsigned numWeights = weightList->length();
152         if (!numWeights)
153             return;
154
155         for (unsigned i = 0; i < numWeights; ++i) {
156             switch (static_cast<CSSPrimitiveValue*>(weightList->itemWithoutBoundsCheck(i))->getIdent()) {
157                 case CSSValueAll:
158                     traitsMask |= FontWeightMask;
159                     break;
160                 case CSSValueBolder:
161                 case CSSValueBold:
162                 case CSSValue700:
163                     traitsMask |= FontWeight700Mask;
164                     break;
165                 case CSSValueNormal:
166                 case CSSValue400:
167                     traitsMask |= FontWeight400Mask;
168                     break;
169                 case CSSValue900:
170                     traitsMask |= FontWeight900Mask;
171                     break;
172                 case CSSValue800:
173                     traitsMask |= FontWeight800Mask;
174                     break;
175                 case CSSValue600:
176                     traitsMask |= FontWeight600Mask;
177                     break;
178                 case CSSValue500:
179                     traitsMask |= FontWeight500Mask;
180                     break;
181                 case CSSValue300:
182                     traitsMask |= FontWeight300Mask;
183                     break;
184                 case CSSValueLighter:
185                 case CSSValue200:
186                     traitsMask |= FontWeight200Mask;
187                     break;
188                 case CSSValue100:
189                     traitsMask |= FontWeight100Mask;
190                     break;
191                 default:
192                     break;
193             }
194         }
195     } else
196         traitsMask |= FontWeightMask;
197
198     if (RefPtr<CSSValue> fontVariant = style->getPropertyCSSValue(CSSPropertyFontVariant)) {
199         if (fontVariant->isPrimitiveValue()) {
200             RefPtr<CSSValueList> list = CSSValueList::createCommaSeparated();
201             list->append(fontVariant);
202             fontVariant = list;
203         } else if (!fontVariant->isValueList())
204             return;
205
206         CSSValueList* variantList = static_cast<CSSValueList*>(fontVariant.get());
207         unsigned numVariants = variantList->length();
208         if (!numVariants)
209             return;
210
211         for (unsigned i = 0; i < numVariants; ++i) {
212             switch (static_cast<CSSPrimitiveValue*>(variantList->itemWithoutBoundsCheck(i))->getIdent()) {
213                 case CSSValueAll:
214                     traitsMask |= FontVariantMask;
215                     break;
216                 case CSSValueNormal:
217                     traitsMask |= FontVariantNormalMask;
218                     break;
219                 case CSSValueSmallCaps:
220                     traitsMask |= FontVariantSmallCapsMask;
221                     break;
222                 default:
223                     break;
224             }
225         }
226     } else
227         traitsMask |= FontVariantMask;
228
229     // Each item in the src property's list is a single CSSFontFaceSource. Put them all into a CSSFontFace.
230     RefPtr<CSSFontFace> fontFace;
231
232     int srcLength = srcList->length();
233
234     bool foundSVGFont = false;
235
236     for (int i = 0; i < srcLength; i++) {
237         // An item in the list either specifies a string (local font name) or a URL (remote font to download).
238         CSSFontFaceSrcValue* item = static_cast<CSSFontFaceSrcValue*>(srcList->itemWithoutBoundsCheck(i));
239         CSSFontFaceSource* source = 0;
240
241 #if ENABLE(SVG_FONTS)
242         foundSVGFont = item->isSVGFontFaceSrc() || item->svgFontFaceElement();
243 #endif
244         if (!item->isLocal()) {
245             Settings* settings = m_document ? m_document->frame() ? m_document->frame()->settings() : 0 : 0;
246             bool allowDownloading = foundSVGFont || (settings && settings->downloadableBinaryFontsEnabled());
247             if (allowDownloading && item->isSupportedFormat() && m_document) {
248                 ResourceRequest request(m_document->completeURL(item->resource()));
249                 CachedFont* cachedFont = m_document->cachedResourceLoader()->requestFont(request);
250                 if (cachedFont) {
251                     source = new CSSFontFaceSource(item->resource(), cachedFont);
252 #if ENABLE(SVG_FONTS)
253                     if (foundSVGFont)
254                         source->setHasExternalSVGFont(true);
255 #endif
256                 }
257             }
258         } else {
259             source = new CSSFontFaceSource(item->resource());
260         }
261
262         if (!fontFace)
263             fontFace = CSSFontFace::create(static_cast<FontTraitsMask>(traitsMask));
264
265         if (source) {
266 #if ENABLE(SVG_FONTS)
267             source->setSVGFontFaceElement(item->svgFontFaceElement());
268 #endif
269             fontFace->addSource(source);
270         }
271     }
272
273     ASSERT(fontFace);
274
275     if (fontFace && !fontFace->isValid())
276         return;
277
278     if (rangeList) {
279         unsigned numRanges = rangeList->length();
280         for (unsigned i = 0; i < numRanges; i++) {
281             CSSUnicodeRangeValue* range = static_cast<CSSUnicodeRangeValue*>(rangeList->itemWithoutBoundsCheck(i));
282             fontFace->addRange(range->from(), range->to());
283         }
284     }
285
286     // Hash under every single family name.
287     int familyLength = familyList->length();
288     for (int i = 0; i < familyLength; i++) {
289         CSSPrimitiveValue* item = static_cast<CSSPrimitiveValue*>(familyList->itemWithoutBoundsCheck(i));
290         String familyName;
291         if (item->primitiveType() == CSSPrimitiveValue::CSS_STRING)
292             familyName = static_cast<FontFamilyValue*>(item)->familyName();
293         else if (item->primitiveType() == CSSPrimitiveValue::CSS_IDENT) {
294             // We need to use the raw text for all the generic family types, since @font-face is a way of actually
295             // defining what font to use for those types.
296             String familyName;
297             switch (item->getIdent()) {
298                 case CSSValueSerif:
299                     familyName = "-webkit-serif";
300                     break;
301                 case CSSValueSansSerif:
302                     familyName = "-webkit-sans-serif";
303                     break;
304                 case CSSValueCursive:
305                     familyName = "-webkit-cursive";
306                     break;
307                 case CSSValueFantasy:
308                     familyName = "-webkit-fantasy";
309                     break;
310                 case CSSValueMonospace:
311                     familyName = "-webkit-monospace";
312                     break;
313                 default:
314                     break;
315             }
316         }
317
318         if (familyName.isEmpty())
319             continue;
320
321         Vector<RefPtr<CSSFontFace> >* familyFontFaces = m_fontFaces.get(familyName);
322         if (!familyFontFaces) {
323             familyFontFaces = new Vector<RefPtr<CSSFontFace> >;
324             m_fontFaces.set(familyName, familyFontFaces);
325
326             ASSERT(!m_locallyInstalledFontFaces.contains(familyName));
327             Vector<RefPtr<CSSFontFace> >* familyLocallyInstalledFaces;
328
329             Vector<unsigned> locallyInstalledFontsTraitsMasks;
330             fontCache()->getTraitsInFamily(familyName, locallyInstalledFontsTraitsMasks);
331             unsigned numLocallyInstalledFaces = locallyInstalledFontsTraitsMasks.size();
332             if (numLocallyInstalledFaces) {
333                 familyLocallyInstalledFaces = new Vector<RefPtr<CSSFontFace> >;
334                 m_locallyInstalledFontFaces.set(familyName, familyLocallyInstalledFaces);
335
336                 for (unsigned i = 0; i < numLocallyInstalledFaces; ++i) {
337                     RefPtr<CSSFontFace> locallyInstalledFontFace = CSSFontFace::create(static_cast<FontTraitsMask>(locallyInstalledFontsTraitsMasks[i]), true);
338                     locallyInstalledFontFace->addSource(new CSSFontFaceSource(familyName));
339                     ASSERT(locallyInstalledFontFace->isValid());
340                     familyLocallyInstalledFaces->append(locallyInstalledFontFace);
341                 }
342             }
343         }
344
345         familyFontFaces->append(fontFace);
346     }
347 }
348
349 void CSSFontSelector::registerForInvalidationCallbacks(FontSelectorClient* client)
350 {
351     m_clients.add(client);
352 }
353
354 void CSSFontSelector::unregisterForInvalidationCallbacks(FontSelectorClient* client)
355 {
356     m_clients.remove(client);
357 }
358
359 void CSSFontSelector::dispatchInvalidationCallbacks()
360 {
361     Vector<FontSelectorClient*> clients;
362     copyToVector(m_clients, clients);
363     for (size_t i = 0; i < clients.size(); ++i)
364         clients[i]->fontsNeedUpdate(this);
365
366     // FIXME: Make Document a FontSelectorClient so that it can simply register for invalidation callbacks.
367     if (!m_document || m_document->inPageCache() || !m_document->renderer())
368         return;
369     m_document->scheduleForcedStyleRecalc();
370 }
371
372 void CSSFontSelector::fontLoaded()
373 {
374     dispatchInvalidationCallbacks();
375 }
376
377 void CSSFontSelector::fontCacheInvalidated()
378 {
379     dispatchInvalidationCallbacks();
380 }
381
382 static FontData* fontDataForGenericFamily(Document* document, const FontDescription& fontDescription, const AtomicString& familyName)
383 {
384     if (!document || !document->frame())
385         return 0;
386
387     const Settings* settings = document->frame()->settings();
388     if (!settings)
389         return 0;
390     
391     AtomicString genericFamily;
392     if (familyName == "-webkit-serif")
393         genericFamily = settings->serifFontFamily();
394     else if (familyName == "-webkit-sans-serif")
395         genericFamily = settings->sansSerifFontFamily();
396     else if (familyName == "-webkit-cursive")
397         genericFamily = settings->cursiveFontFamily();
398     else if (familyName == "-webkit-fantasy")
399         genericFamily = settings->fantasyFontFamily();
400     else if (familyName == "-webkit-monospace")
401         genericFamily = settings->fixedFontFamily();
402     else if (familyName == "-webkit-standard")
403         genericFamily = settings->standardFontFamily();
404
405     if (!genericFamily.isEmpty())
406         return fontCache()->getCachedFontData(fontDescription, genericFamily);
407
408     return 0;
409 }
410
411 static FontTraitsMask desiredTraitsMaskForComparison;
412
413 static inline bool compareFontFaces(CSSFontFace* first, CSSFontFace* second)
414 {
415     FontTraitsMask firstTraitsMask = first->traitsMask();
416     FontTraitsMask secondTraitsMask = second->traitsMask();
417
418     bool firstHasDesiredVariant = firstTraitsMask & desiredTraitsMaskForComparison & FontVariantMask;
419     bool secondHasDesiredVariant = secondTraitsMask & desiredTraitsMaskForComparison & FontVariantMask;
420
421     if (firstHasDesiredVariant != secondHasDesiredVariant)
422         return firstHasDesiredVariant;
423
424     if ((desiredTraitsMaskForComparison & FontVariantSmallCapsMask) && !first->isLocalFallback() && !second->isLocalFallback()) {
425         // Prefer a font that has indicated that it can only support small-caps to a font that claims to support
426         // all variants.  The specialized font is more likely to be true small-caps and not require synthesis.
427         bool firstRequiresSmallCaps = (firstTraitsMask & FontVariantSmallCapsMask) && !(firstTraitsMask & FontVariantNormalMask);
428         bool secondRequiresSmallCaps = (secondTraitsMask & FontVariantSmallCapsMask) && !(secondTraitsMask & FontVariantNormalMask);
429         if (firstRequiresSmallCaps != secondRequiresSmallCaps)
430             return firstRequiresSmallCaps;
431     }
432
433     bool firstHasDesiredStyle = firstTraitsMask & desiredTraitsMaskForComparison & FontStyleMask;
434     bool secondHasDesiredStyle = secondTraitsMask & desiredTraitsMaskForComparison & FontStyleMask;
435
436     if (firstHasDesiredStyle != secondHasDesiredStyle)
437         return firstHasDesiredStyle;
438
439     if ((desiredTraitsMaskForComparison & FontStyleItalicMask) && !first->isLocalFallback() && !second->isLocalFallback()) {
440         // Prefer a font that has indicated that it can only support italics to a font that claims to support
441         // all styles.  The specialized font is more likely to be the one the author wants used.
442         bool firstRequiresItalics = (firstTraitsMask & FontStyleItalicMask) && !(firstTraitsMask & FontStyleNormalMask);
443         bool secondRequiresItalics = (secondTraitsMask & FontStyleItalicMask) && !(secondTraitsMask & FontStyleNormalMask);
444         if (firstRequiresItalics != secondRequiresItalics)
445             return firstRequiresItalics;
446     }
447
448     if (secondTraitsMask & desiredTraitsMaskForComparison & FontWeightMask)
449         return false;
450     if (firstTraitsMask & desiredTraitsMaskForComparison & FontWeightMask)
451         return true;
452
453     // http://www.w3.org/TR/2002/WD-css3-webfonts-20020802/#q46 says: "If there are fewer then 9 weights in the family, the default algorithm
454     // for filling the "holes" is as follows. If '500' is unassigned, it will be assigned the same font as '400'. If any of the values '600',
455     // '700', '800', or '900' remains unassigned, they are assigned to the same face as the next darker assigned keyword, if any, or the next
456     // lighter one otherwise. If any of '300', '200', or '100' remains unassigned, it is assigned to the next lighter assigned keyword, if any,
457     // or the next darker otherwise."
458     // For '400', we made up our own rule (which then '500' follows).
459
460     static const unsigned fallbackRuleSets = 9;
461     static const unsigned rulesPerSet = 8;
462     static const FontTraitsMask weightFallbackRuleSets[fallbackRuleSets][rulesPerSet] = {
463         { FontWeight200Mask, FontWeight300Mask, FontWeight400Mask, FontWeight500Mask, FontWeight600Mask, FontWeight700Mask, FontWeight800Mask, FontWeight900Mask },
464         { FontWeight100Mask, FontWeight300Mask, FontWeight400Mask, FontWeight500Mask, FontWeight600Mask, FontWeight700Mask, FontWeight800Mask, FontWeight900Mask },
465         { FontWeight200Mask, FontWeight100Mask, FontWeight400Mask, FontWeight500Mask, FontWeight600Mask, FontWeight700Mask, FontWeight800Mask, FontWeight900Mask },
466         { FontWeight500Mask, FontWeight300Mask, FontWeight600Mask, FontWeight200Mask, FontWeight700Mask, FontWeight100Mask, FontWeight800Mask, FontWeight900Mask },
467         { FontWeight400Mask, FontWeight300Mask, FontWeight600Mask, FontWeight200Mask, FontWeight700Mask, FontWeight100Mask, FontWeight800Mask, FontWeight900Mask },
468         { FontWeight700Mask, FontWeight800Mask, FontWeight900Mask, FontWeight500Mask, FontWeight400Mask, FontWeight300Mask, FontWeight200Mask, FontWeight100Mask },
469         { FontWeight800Mask, FontWeight900Mask, FontWeight600Mask, FontWeight500Mask, FontWeight400Mask, FontWeight300Mask, FontWeight200Mask, FontWeight100Mask },
470         { FontWeight900Mask, FontWeight700Mask, FontWeight600Mask, FontWeight500Mask, FontWeight400Mask, FontWeight300Mask, FontWeight200Mask, FontWeight100Mask },
471         { FontWeight800Mask, FontWeight700Mask, FontWeight600Mask, FontWeight500Mask, FontWeight400Mask, FontWeight300Mask, FontWeight200Mask, FontWeight100Mask }
472     };
473
474     unsigned ruleSetIndex = 0;
475     unsigned w = FontWeight100Bit;
476     while (!(desiredTraitsMaskForComparison & (1 << w))) {
477         w++;
478         ruleSetIndex++;
479     }
480
481     ASSERT(ruleSetIndex < fallbackRuleSets);
482     const FontTraitsMask* weightFallbackRule = weightFallbackRuleSets[ruleSetIndex];
483     for (unsigned i = 0; i < rulesPerSet; ++i) {
484         if (secondTraitsMask & weightFallbackRule[i])
485             return false;
486         if (firstTraitsMask & weightFallbackRule[i])
487             return true;
488     }
489
490     return false;
491 }
492
493 FontData* CSSFontSelector::getFontData(const FontDescription& fontDescription, const AtomicString& familyName)
494 {
495     if (m_fontFaces.isEmpty()) {
496         if (familyName.startsWith("-webkit-"))
497             return fontDataForGenericFamily(m_document, fontDescription, familyName);
498         return 0;
499     }
500
501     String family = familyName.string();
502
503     Vector<RefPtr<CSSFontFace> >* familyFontFaces = m_fontFaces.get(family);
504     // If no face was found, then return 0 and let the OS come up with its best match for the name.
505     if (!familyFontFaces || familyFontFaces->isEmpty()) {
506         // If we were handed a generic family, but there was no match, go ahead and return the correct font based off our
507         // settings.
508         return fontDataForGenericFamily(m_document, fontDescription, familyName);
509     }
510
511     HashMap<unsigned, RefPtr<CSSSegmentedFontFace> >* segmentedFontFaceCache = m_fonts.get(family);
512     if (!segmentedFontFaceCache) {
513         segmentedFontFaceCache = new HashMap<unsigned, RefPtr<CSSSegmentedFontFace> >;
514         m_fonts.set(family, segmentedFontFaceCache);
515     }
516
517     FontTraitsMask traitsMask = fontDescription.traitsMask();
518
519     RefPtr<CSSSegmentedFontFace> face = segmentedFontFaceCache->get(traitsMask);
520
521     if (!face) {
522         face = CSSSegmentedFontFace::create(this);
523         segmentedFontFaceCache->set(traitsMask, face);
524         // Collect all matching faces and sort them in order of preference.
525         Vector<CSSFontFace*, 32> candidateFontFaces;
526         for (int i = familyFontFaces->size() - 1; i >= 0; --i) {
527             CSSFontFace* candidate = familyFontFaces->at(i).get();
528             unsigned candidateTraitsMask = candidate->traitsMask();
529             if ((traitsMask & FontStyleNormalMask) && !(candidateTraitsMask & FontStyleNormalMask))
530                 continue;
531             if ((traitsMask & FontVariantNormalMask) && !(candidateTraitsMask & FontVariantNormalMask))
532                 continue;
533 #if ENABLE(SVG_FONTS)
534             // For SVG Fonts that specify that they only support the "normal" variant, we will assume they are incapable
535             // of small-caps synthesis and just ignore the font face as a candidate.
536             if (candidate->hasSVGFontFaceSource() && (traitsMask & FontVariantSmallCapsMask) && !(candidateTraitsMask & FontVariantSmallCapsMask))
537                 continue;
538 #endif
539             candidateFontFaces.append(candidate);
540         }
541
542         if (Vector<RefPtr<CSSFontFace> >* familyLocallyInstalledFontFaces = m_locallyInstalledFontFaces.get(family)) {
543             unsigned numLocallyInstalledFontFaces = familyLocallyInstalledFontFaces->size();
544             for (unsigned i = 0; i < numLocallyInstalledFontFaces; ++i) {
545                 CSSFontFace* candidate = familyLocallyInstalledFontFaces->at(i).get();
546                 unsigned candidateTraitsMask = candidate->traitsMask();
547                 if ((traitsMask & FontStyleNormalMask) && !(candidateTraitsMask & FontStyleNormalMask))
548                     continue;
549                 if ((traitsMask & FontVariantNormalMask) && !(candidateTraitsMask & FontVariantNormalMask))
550                     continue;
551                 candidateFontFaces.append(candidate);
552             }
553         }
554
555         desiredTraitsMaskForComparison = traitsMask;
556         std::stable_sort(candidateFontFaces.begin(), candidateFontFaces.end(), compareFontFaces);
557         unsigned numCandidates = candidateFontFaces.size();
558         for (unsigned i = 0; i < numCandidates; ++i)
559             face->appendFontFace(candidateFontFaces[i]);
560     }
561
562     // We have a face.  Ask it for a font data.  If it cannot produce one, it will fail, and the OS will take over.
563     return face->getFontData(fontDescription);
564 }
565
566 }