src/third_party/WebKit/Source/core/css/RuleSet.cpp

   1 /*
   2  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
   3  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
   4  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
   5  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
   6  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
   7  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
   8  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
   9  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  10  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
  11  * Copyright (C) 2012 Google Inc. All rights reserved.
  12  *
  13  * This library is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU Library General Public
  15  * License as published by the Free Software Foundation; either
  16  * version 2 of the License, or (at your option) any later version.
  17  *
  18  * This library is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  * Library General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU Library General Public License
  24  * along with this library; see the file COPYING.LIB.  If not, write to
  25  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  26  * Boston, MA 02110-1301, USA.
  27  */
  28
  29 #include "config.h"
  30 #include "core/css/RuleSet.h"
  31
  32 #include "core/HTMLNames.h"
  33 #include "core/css/CSSFontSelector.h"
  34 #include "core/css/CSSSelector.h"
  35 #include "core/css/CSSSelectorList.h"
  36 #include "core/css/SelectorChecker.h"
  37 #include "core/css/SelectorFilter.h"
  38 #include "core/css/StyleRuleImport.h"
  39 #include "core/css/StyleSheetContents.h"
  40 #include "core/html/track/TextTrackCue.h"
  41 #include "platform/RuntimeEnabledFeatures.h"
  42 #include "platform/TraceEvent.h"
  43 #include "platform/heap/HeapTerminatedArrayBuilder.h"
  44 #include "platform/weborigin/SecurityOrigin.h"
  45
  46 #include "wtf/TerminatedArrayBuilder.h"
  47
  48 namespace blink {
  49
  50 using namespace HTMLNames;
  51
  52 // -----------------------------------------------------------------
  53
  54 static inline bool isSelectorMatchingHTMLBasedOnRuleHash(const CSSSelector& selector)
  55 {
  56     if (selector.match() == CSSSelector::Tag) {
  57         const AtomicString& selectorNamespace = selector.tagQName().namespaceURI();
  58         if (selectorNamespace != starAtom && selectorNamespace != xhtmlNamespaceURI)
  59             return false;
  60         if (selector.relation() == CSSSelector::SubSelector && selector.tagHistory())
  61             return isSelectorMatchingHTMLBasedOnRuleHash(*selector.tagHistory());
  62         return true;
  63     }
  64     if (SelectorChecker::isCommonPseudoClassSelector(selector))
  65         return true;
  66     return selector.match() == CSSSelector::Id || selector.match() == CSSSelector::Class;
  67 }
  68
  69 static inline bool selectorListContainsUncommonAttributeSelector(const CSSSelector* selector)
  70 {
  71     const CSSSelectorList* selectorList = selector->selectorList();
  72     if (!selectorList)
  73         return false;
  74     for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector)) {
  75         for (const CSSSelector* component = selector; component; component = component->tagHistory()) {
  76             if (component->isAttributeSelector())
  77                 return true;
  78         }
  79     }
  80     return false;
  81 }
  82
  83 static inline bool isCommonAttributeSelectorAttribute(const QualifiedName& attribute)
  84 {
  85     // These are explicitly tested for equality in canShareStyleWithElement.
  86     return attribute == typeAttr || attribute == readonlyAttr;
  87 }
  88
  89 static inline bool containsUncommonAttributeSelector(const CSSSelector& selector)
  90 {
  91     const CSSSelector* current = &selector;
  92     for (; current; current = current->tagHistory()) {
  93         // Allow certain common attributes (used in the default style) in the selectors that match the current element.
  94         if (current->isAttributeSelector() && !isCommonAttributeSelectorAttribute(current->attribute()))
  95             return true;
  96         if (selectorListContainsUncommonAttributeSelector(current))
  97             return true;
  98         if (current->relation() != CSSSelector::SubSelector) {
  99             current = current->tagHistory();
 100             break;
 101         }
 102     }
 103
 104     for (; current; current = current->tagHistory()) {
 105         if (current->isAttributeSelector())
 106             return true;
 107         if (selectorListContainsUncommonAttributeSelector(current))
 108             return true;
 109     }
 110     return false;
 111 }
 112
 113 static inline PropertyWhitelistType determinePropertyWhitelistType(const AddRuleFlags addRuleFlags, const CSSSelector& selector)
 114 {
 115     for (const CSSSelector* component = &selector; component; component = component->tagHistory()) {
 116         if (component->pseudoType() == CSSSelector::PseudoCue || (component->match() == CSSSelector::PseudoElement && component->value() == TextTrackCue::cueShadowPseudoId()))
 117             return PropertyWhitelistCue;
 118         if (component->pseudoType() == CSSSelector::PseudoFirstLetter)
 119             return PropertyWhitelistFirstLetter;
 120     }
 121     return PropertyWhitelistNone;
 122 }
 123
 124 RuleData::RuleData(StyleRule* rule, unsigned selectorIndex, unsigned position, AddRuleFlags addRuleFlags)
 125     : m_rule(rule)
 126     , m_selectorIndex(selectorIndex)
 127     , m_isLastInArray(false)
 128     , m_position(position)
 129     , m_specificity(selector().specificity())
 130     , m_hasMultipartSelector(!!selector().tagHistory())
 131     , m_hasRightmostSelectorMatchingHTMLBasedOnRuleHash(isSelectorMatchingHTMLBasedOnRuleHash(selector()))
 132     , m_containsUncommonAttributeSelector(blink::containsUncommonAttributeSelector(selector()))
 133     , m_linkMatchType(SelectorChecker::determineLinkMatchType(selector()))
 134     , m_hasDocumentSecurityOrigin(addRuleFlags & RuleHasDocumentSecurityOrigin)
 135     , m_propertyWhitelistType(determinePropertyWhitelistType(addRuleFlags, selector()))
 136 {
 137     ASSERT(m_position == position);
 138     ASSERT(m_selectorIndex == selectorIndex);
 139     SelectorFilter::collectIdentifierHashes(selector(), m_descendantSelectorIdentifierHashes, maximumIdentifierCount);
 140 }
 141
 142 void RuleSet::addToRuleSet(const AtomicString& key, PendingRuleMap& map, const RuleData& ruleData)
 143 {
 144     OwnPtrWillBeMember<WillBeHeapLinkedStack<RuleData> >& rules = map.add(key, nullptr).storedValue->value;
 145     if (!rules)
 146         rules = adoptPtrWillBeNoop(new WillBeHeapLinkedStack<RuleData>);
 147     rules->push(ruleData);
 148 }
 149
 150 static void extractValuesforSelector(const CSSSelector* selector, AtomicString& id, AtomicString& className, AtomicString& customPseudoElementName, AtomicString& tagName)
 151 {
 152     switch (selector->match()) {
 153     case CSSSelector::Id:
 154         id = selector->value();
 155         break;
 156     case CSSSelector::Class:
 157         className = selector->value();
 158         break;
 159     case CSSSelector::Tag:
 160         if (selector->tagQName().localName() != starAtom)
 161             tagName = selector->tagQName().localName();
 162         break;
 163     default:
 164         break;
 165     }
 166     if (selector->isCustomPseudoElement())
 167         customPseudoElementName = selector->value();
 168 }
 169
 170 bool RuleSet::findBestRuleSetAndAdd(const CSSSelector& component, RuleData& ruleData)
 171 {
 172     AtomicString id;
 173     AtomicString className;
 174     AtomicString customPseudoElementName;
 175     AtomicString tagName;
 176
 177 #ifndef NDEBUG
 178     m_allRules.append(ruleData);
 179 #endif
 180
 181     const CSSSelector* it = &component;
 182     for (; it && it->relation() == CSSSelector::SubSelector; it = it->tagHistory())
 183         extractValuesforSelector(it, id, className, customPseudoElementName, tagName);
 184     if (it)
 185         extractValuesforSelector(it, id, className, customPseudoElementName, tagName);
 186
 187     // Prefer rule sets in order of most likely to apply infrequently.
 188     if (!id.isEmpty()) {
 189         addToRuleSet(id, ensurePendingRules()->idRules, ruleData);
 190         return true;
 191     }
 192     if (!className.isEmpty()) {
 193         addToRuleSet(className, ensurePendingRules()->classRules, ruleData);
 194         return true;
 195     }
 196     if (!customPseudoElementName.isEmpty()) {
 197         // Custom pseudos come before ids and classes in the order of tagHistory, and have a relation of
 198         // ShadowPseudo between them. Therefore we should never be a situation where extractValuesforSelector
 199         // finsd id and className in addition to custom pseudo.
 200         ASSERT(id.isEmpty() && className.isEmpty());
 201         addToRuleSet(customPseudoElementName, ensurePendingRules()->shadowPseudoElementRules, ruleData);
 202         return true;
 203     }
 204
 205     if (component.pseudoType() == CSSSelector::PseudoCue) {
 206         m_cuePseudoRules.append(ruleData);
 207         return true;
 208     }
 209
 210     if (SelectorChecker::isCommonPseudoClassSelector(component)) {
 211         switch (component.pseudoType()) {
 212         case CSSSelector::PseudoLink:
 213         case CSSSelector::PseudoVisited:
 214         case CSSSelector::PseudoAnyLink:
 215             m_linkPseudoClassRules.append(ruleData);
 216             return true;
 217         case CSSSelector::PseudoFocus:
 218             m_focusPseudoClassRules.append(ruleData);
 219             return true;
 220         default:
 221             ASSERT_NOT_REACHED();
 222             return true;
 223         }
 224     }
 225
 226     if (!tagName.isEmpty()) {
 227         addToRuleSet(tagName, ensurePendingRules()->tagRules, ruleData);
 228         return true;
 229     }
 230
 231     return false;
 232 }
 233
 234 void RuleSet::addRule(StyleRule* rule, unsigned selectorIndex, AddRuleFlags addRuleFlags)
 235 {
 236     RuleData ruleData(rule, selectorIndex, m_ruleCount++, addRuleFlags);
 237     m_features.collectFeaturesFromRuleData(ruleData);
 238
 239     if (!findBestRuleSetAndAdd(ruleData.selector(), ruleData)) {
 240         // If we didn't find a specialized map to stick it in, file under universal rules.
 241         m_universalRules.append(ruleData);
 242     }
 243 }
 244
 245 void RuleSet::addPageRule(StyleRulePage* rule)
 246 {
 247     ensurePendingRules(); // So that m_pageRules.shrinkToFit() gets called.
 248     m_pageRules.append(rule);
 249 }
 250
 251 void RuleSet::addViewportRule(StyleRuleViewport* rule)
 252 {
 253     ensurePendingRules(); // So that m_viewportRules.shrinkToFit() gets called.
 254     m_viewportRules.append(rule);
 255 }
 256
 257 void RuleSet::addFontFaceRule(StyleRuleFontFace* rule)
 258 {
 259     ensurePendingRules(); // So that m_fontFaceRules.shrinkToFit() gets called.
 260     m_fontFaceRules.append(rule);
 261 }
 262
 263 void RuleSet::addKeyframesRule(StyleRuleKeyframes* rule)
 264 {
 265     ensurePendingRules(); // So that m_keyframesRules.shrinkToFit() gets called.
 266     m_keyframesRules.append(rule);
 267 }
 268
 269 void RuleSet::addChildRules(const WillBeHeapVector<RefPtrWillBeMember<StyleRuleBase> >& rules, const MediaQueryEvaluator& medium, AddRuleFlags addRuleFlags)
 270 {
 271     for (unsigned i = 0; i < rules.size(); ++i) {
 272         StyleRuleBase* rule = rules[i].get();
 273
 274         if (rule->isStyleRule()) {
 275             StyleRule* styleRule = toStyleRule(rule);
 276
 277             const CSSSelectorList& selectorList = styleRule->selectorList();
 278             for (size_t selectorIndex = 0; selectorIndex != kNotFound; selectorIndex = selectorList.indexOfNextSelectorAfter(selectorIndex)) {
 279                 if (selectorList.selectorCrossesTreeScopes(selectorIndex)) {
 280                     m_treeBoundaryCrossingRules.append(MinimalRuleData(styleRule, selectorIndex, addRuleFlags));
 281                 } else if (selectorList.hasShadowDistributedAt(selectorIndex)) {
 282                     m_shadowDistributedRules.append(MinimalRuleData(styleRule, selectorIndex, addRuleFlags));
 283                 } else {
 284                     addRule(styleRule, selectorIndex, addRuleFlags);
 285                 }
 286             }
 287         } else if (rule->isPageRule()) {
 288             addPageRule(toStyleRulePage(rule));
 289         } else if (rule->isMediaRule()) {
 290             StyleRuleMedia* mediaRule = toStyleRuleMedia(rule);
 291             if ((!mediaRule->mediaQueries() || medium.eval(mediaRule->mediaQueries(), &m_viewportDependentMediaQueryResults)))
 292                 addChildRules(mediaRule->childRules(), medium, addRuleFlags);
 293         } else if (rule->isFontFaceRule()) {
 294             addFontFaceRule(toStyleRuleFontFace(rule));
 295         } else if (rule->isKeyframesRule()) {
 296             addKeyframesRule(toStyleRuleKeyframes(rule));
 297         } else if (rule->isViewportRule()) {
 298             addViewportRule(toStyleRuleViewport(rule));
 299         } else if (rule->isSupportsRule() && toStyleRuleSupports(rule)->conditionIsSupported()) {
 300             addChildRules(toStyleRuleSupports(rule)->childRules(), medium, addRuleFlags);
 301         }
 302     }
 303 }
 304
 305 void RuleSet::addRulesFromSheet(StyleSheetContents* sheet, const MediaQueryEvaluator& medium, AddRuleFlags addRuleFlags)
 306 {
 307     TRACE_EVENT0("blink", "RuleSet::addRulesFromSheet");
 308
 309     ASSERT(sheet);
 310
 311     addRuleFlags = static_cast<AddRuleFlags>(addRuleFlags | RuleCanUseFastCheckSelector);
 312     const WillBeHeapVector<RefPtrWillBeMember<StyleRuleImport> >& importRules = sheet->importRules();
 313     for (unsigned i = 0; i < importRules.size(); ++i) {
 314         StyleRuleImport* importRule = importRules[i].get();
 315         if (importRule->styleSheet() && (!importRule->mediaQueries() || medium.eval(importRule->mediaQueries(), &m_viewportDependentMediaQueryResults)))
 316             addRulesFromSheet(importRule->styleSheet(), medium, addRuleFlags);
 317     }
 318
 319     addChildRules(sheet->childRules(), medium, addRuleFlags);
 320 }
 321
 322 void RuleSet::addStyleRule(StyleRule* rule, AddRuleFlags addRuleFlags)
 323 {
 324     for (size_t selectorIndex = 0; selectorIndex != kNotFound; selectorIndex = rule->selectorList().indexOfNextSelectorAfter(selectorIndex))
 325         addRule(rule, selectorIndex, addRuleFlags);
 326 }
 327
 328 void RuleSet::compactPendingRules(PendingRuleMap& pendingMap, CompactRuleMap& compactMap)
 329 {
 330     for (auto& item : pendingMap) {
 331         OwnPtrWillBeRawPtr<WillBeHeapLinkedStack<RuleData> > pendingRules = item.value.release();
 332         CompactRuleMap::ValueType* compactRules = compactMap.add(item.key, nullptr).storedValue;
 333
 334         WillBeHeapTerminatedArrayBuilder<RuleData> builder(compactRules->value.release());
 335         builder.grow(pendingRules->size());
 336         while (!pendingRules->isEmpty()) {
 337             builder.append(pendingRules->peek());
 338             pendingRules->pop();
 339         }
 340
 341         compactRules->value = builder.release();
 342     }
 343 }
 344
 345 void RuleSet::compactRules()
 346 {
 347     ASSERT(m_pendingRules);
 348     OwnPtrWillBeRawPtr<PendingRuleMaps> pendingRules = m_pendingRules.release();
 349     compactPendingRules(pendingRules->idRules, m_idRules);
 350     compactPendingRules(pendingRules->classRules, m_classRules);
 351     compactPendingRules(pendingRules->tagRules, m_tagRules);
 352     compactPendingRules(pendingRules->shadowPseudoElementRules, m_shadowPseudoElementRules);
 353     m_linkPseudoClassRules.shrinkToFit();
 354     m_cuePseudoRules.shrinkToFit();
 355     m_focusPseudoClassRules.shrinkToFit();
 356     m_universalRules.shrinkToFit();
 357     m_pageRules.shrinkToFit();
 358     m_viewportRules.shrinkToFit();
 359     m_fontFaceRules.shrinkToFit();
 360     m_keyframesRules.shrinkToFit();
 361     m_treeBoundaryCrossingRules.shrinkToFit();
 362     m_shadowDistributedRules.shrinkToFit();
 363 }
 364
 365 void MinimalRuleData::trace(Visitor* visitor)
 366 {
 367     visitor->trace(m_rule);
 368 }
 369
 370 void RuleData::trace(Visitor* visitor)
 371 {
 372     visitor->trace(m_rule);
 373 }
 374
 375 void RuleSet::PendingRuleMaps::trace(Visitor* visitor)
 376 {
 377 #if ENABLE(OILPAN)
 378     visitor->trace(idRules);
 379     visitor->trace(classRules);
 380     visitor->trace(tagRules);
 381     visitor->trace(shadowPseudoElementRules);
 382 #endif
 383 }
 384
 385 void RuleSet::trace(Visitor* visitor)
 386 {
 387 #if ENABLE(OILPAN)
 388     visitor->trace(m_idRules);
 389     visitor->trace(m_classRules);
 390     visitor->trace(m_tagRules);
 391     visitor->trace(m_shadowPseudoElementRules);
 392     visitor->trace(m_linkPseudoClassRules);
 393     visitor->trace(m_cuePseudoRules);
 394     visitor->trace(m_focusPseudoClassRules);
 395     visitor->trace(m_universalRules);
 396     visitor->trace(m_features);
 397     visitor->trace(m_pageRules);
 398     visitor->trace(m_viewportRules);
 399     visitor->trace(m_fontFaceRules);
 400     visitor->trace(m_keyframesRules);
 401     visitor->trace(m_treeBoundaryCrossingRules);
 402     visitor->trace(m_shadowDistributedRules);
 403     visitor->trace(m_viewportDependentMediaQueryResults);
 404     visitor->trace(m_pendingRules);
 405 #ifndef NDEBUG
 406     visitor->trace(m_allRules);
 407 #endif
 408 #endif
 409 }
 410
 411 #ifndef NDEBUG
 412 void RuleSet::show()
 413 {
 414     for (const auto& rule: m_allRules)
 415         rule.selector().show();
 416 }
 417 #endif
 418
 419 } // namespace blink