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 "RuleSet.h"
31
32#include "CSSFontSelector.h"
33#include "CSSSelector.h"
34#include "CSSSelectorList.h"
35#include "HTMLNames.h"
36#include "MediaQueryEvaluator.h"
37#include "SecurityOrigin.h"
38#include "SelectorChecker.h"
39#include "SelectorCheckerFastPath.h"
40#include "SelectorFilter.h"
41#include "StyleResolver.h"
42#include "StyleRule.h"
43#include "StyleRuleImport.h"
44#include "StyleSheetContents.h"
45#include "WebKitCSSKeyframesRule.h"
46
47#if ENABLE(VIDEO_TRACK)
48#include "TextTrackCue.h"
49#endif
50
51namespace WebCore {
52
53using namespace HTMLNames;
54
55// -----------------------------------------------------------------
56
57static inline bool isSelectorMatchingHTMLBasedOnRuleHash(const CSSSelector* selector)
58{
59    ASSERT(selector);
60    if (selector->m_match == CSSSelector::Tag) {
61        const AtomicString& selectorNamespace = selector->tagQName().namespaceURI();
62        if (selectorNamespace != starAtom && selectorNamespace != xhtmlNamespaceURI)
63            return false;
64        if (selector->relation() == CSSSelector::SubSelector)
65            return isSelectorMatchingHTMLBasedOnRuleHash(selector->tagHistory());
66        return true;
67    }
68    if (SelectorChecker::isCommonPseudoClassSelector(selector))
69        return true;
70    return selector->m_match == CSSSelector::Id || selector->m_match == CSSSelector::Class;
71}
72
73static inline bool selectorListContainsUncommonAttributeSelector(const CSSSelector* selector)
74{
75    const CSSSelectorList* selectorList = selector->selectorList();
76    if (!selectorList)
77        return false;
78    for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(selector)) {
79        for (const CSSSelector* component = selector; component; component = component->tagHistory()) {
80            if (component->isAttributeSelector())
81                return true;
82        }
83    }
84    return false;
85}
86
87static inline bool isCommonAttributeSelectorAttribute(const QualifiedName& attribute)
88{
89    // These are explicitly tested for equality in canShareStyleWithElement.
90    return attribute == typeAttr || attribute == readonlyAttr;
91}
92
93static inline bool containsUncommonAttributeSelector(const CSSSelector* selector)
94{
95    for (; selector; selector = selector->tagHistory()) {
96        // Allow certain common attributes (used in the default style) in the selectors that match the current element.
97        if (selector->isAttributeSelector() && !isCommonAttributeSelectorAttribute(selector->attribute()))
98            return true;
99        if (selectorListContainsUncommonAttributeSelector(selector))
100            return true;
101        if (selector->relation() != CSSSelector::SubSelector) {
102            selector = selector->tagHistory();
103            break;
104        }
105    }
106
107    for (; selector; selector = selector->tagHistory()) {
108        if (selector->isAttributeSelector())
109            return true;
110        if (selectorListContainsUncommonAttributeSelector(selector))
111            return true;
112    }
113    return false;
114}
115
116static inline PropertyWhitelistType determinePropertyWhitelistType(const AddRuleFlags addRuleFlags, const CSSSelector* selector)
117{
118    if (addRuleFlags & RuleIsInRegionRule)
119        return PropertyWhitelistRegion;
120#if ENABLE(VIDEO_TRACK)
121    for (const CSSSelector* component = selector; component; component = component->tagHistory()) {
122        if (component->pseudoType() == CSSSelector::PseudoCue || (component->m_match == CSSSelector::PseudoElement && component->value() == TextTrackCue::cueShadowPseudoId()))
123            return PropertyWhitelistCue;
124    }
125#else
126    UNUSED_PARAM(selector);
127#endif
128    return PropertyWhitelistNone;
129}
130
131RuleData::RuleData(StyleRule* rule, unsigned selectorIndex, unsigned position, AddRuleFlags addRuleFlags)
132    : m_rule(rule)
133    , m_selectorIndex(selectorIndex)
134    , m_position(position)
135    , m_hasFastCheckableSelector((addRuleFlags & RuleCanUseFastCheckSelector) && SelectorCheckerFastPath::canUse(selector()))
136    , m_specificity(selector()->specificity())
137    , m_hasMultipartSelector(!!selector()->tagHistory())
138    , m_hasRightmostSelectorMatchingHTMLBasedOnRuleHash(isSelectorMatchingHTMLBasedOnRuleHash(selector()))
139    , m_containsUncommonAttributeSelector(WebCore::containsUncommonAttributeSelector(selector()))
140    , m_linkMatchType(SelectorChecker::determineLinkMatchType(selector()))
141    , m_hasDocumentSecurityOrigin(addRuleFlags & RuleHasDocumentSecurityOrigin)
142    , m_propertyWhitelistType(determinePropertyWhitelistType(addRuleFlags, selector()))
143{
144    ASSERT(m_position == position);
145    ASSERT(m_selectorIndex == selectorIndex);
146    SelectorFilter::collectIdentifierHashes(selector(), m_descendantSelectorIdentifierHashes, maximumIdentifierCount);
147}
148
149static void collectFeaturesFromRuleData(RuleFeatureSet& features, const RuleData& ruleData)
150{
151    bool foundSiblingSelector = false;
152    for (const CSSSelector* selector = ruleData.selector(); selector; selector = selector->tagHistory()) {
153        features.collectFeaturesFromSelector(selector);
154
155        if (const CSSSelectorList* selectorList = selector->selectorList()) {
156            for (const CSSSelector* subSelector = selectorList->first(); subSelector; subSelector = CSSSelectorList::next(subSelector)) {
157                if (!foundSiblingSelector && selector->isSiblingSelector())
158                    foundSiblingSelector = true;
159                features.collectFeaturesFromSelector(subSelector);
160            }
161        } else if (!foundSiblingSelector && selector->isSiblingSelector())
162            foundSiblingSelector = true;
163    }
164    if (foundSiblingSelector)
165        features.siblingRules.append(RuleFeature(ruleData.rule(), ruleData.selectorIndex(), ruleData.hasDocumentSecurityOrigin()));
166    if (ruleData.containsUncommonAttributeSelector())
167        features.uncommonAttributeRules.append(RuleFeature(ruleData.rule(), ruleData.selectorIndex(), ruleData.hasDocumentSecurityOrigin()));
168}
169
170void RuleSet::addToRuleSet(AtomicStringImpl* key, AtomRuleMap& map, const RuleData& ruleData)
171{
172    if (!key)
173        return;
174    OwnPtr<Vector<RuleData> >& rules = map.add(key, nullptr).iterator->value;
175    if (!rules)
176        rules = adoptPtr(new Vector<RuleData>);
177    rules->append(ruleData);
178}
179
180bool RuleSet::findBestRuleSetAndAdd(const CSSSelector* component, RuleData& ruleData)
181{
182    if (component->m_match == CSSSelector::Id) {
183        addToRuleSet(component->value().impl(), m_idRules, ruleData);
184        return true;
185    }
186    if (component->m_match == CSSSelector::Class) {
187        addToRuleSet(component->value().impl(), m_classRules, ruleData);
188        return true;
189    }
190    if (component->isCustomPseudoElement()) {
191        addToRuleSet(component->value().impl(), m_shadowPseudoElementRules, ruleData);
192        return true;
193    }
194#if ENABLE(VIDEO_TRACK)
195    if (component->pseudoType() == CSSSelector::PseudoCue) {
196        m_cuePseudoRules.append(ruleData);
197        return true;
198    }
199#endif
200    if (SelectorChecker::isCommonPseudoClassSelector(component)) {
201        switch (component->pseudoType()) {
202        case CSSSelector::PseudoLink:
203        case CSSSelector::PseudoVisited:
204        case CSSSelector::PseudoAnyLink:
205            m_linkPseudoClassRules.append(ruleData);
206            return true;
207        case CSSSelector::PseudoFocus:
208            m_focusPseudoClassRules.append(ruleData);
209            return true;
210        default:
211            ASSERT_NOT_REACHED();
212            return true;
213        }
214    }
215
216    if (component->m_match == CSSSelector::Tag) {
217        // If this is part of a subselector chain, recurse ahead to find a narrower set (ID/class/:pseudo)
218        if (component->relation() == CSSSelector::SubSelector) {
219            const CSSSelector* nextComponent = component->tagHistory();
220            if (nextComponent->m_match == CSSSelector::Class || nextComponent->m_match == CSSSelector::Id || SelectorChecker::isCommonPseudoClassSelector(nextComponent)) {
221                if (findBestRuleSetAndAdd(nextComponent, ruleData))
222                    return true;
223            }
224        }
225        if (component->tagQName().localName() != starAtom) {
226            addToRuleSet(component->tagQName().localName().impl(), m_tagRules, ruleData);
227            return true;
228        }
229    }
230    return false;
231}
232
233void RuleSet::addRule(StyleRule* rule, unsigned selectorIndex, AddRuleFlags addRuleFlags)
234{
235    RuleData ruleData(rule, selectorIndex, m_ruleCount++, addRuleFlags);
236    collectFeaturesFromRuleData(m_features, ruleData);
237
238    if (!findBestRuleSetAndAdd(ruleData.selector(), ruleData)) {
239        // If we didn't find a specialized map to stick it in, file under universal rules.
240        m_universalRules.append(ruleData);
241    }
242}
243
244void RuleSet::addPageRule(StyleRulePage* rule)
245{
246    m_pageRules.append(rule);
247}
248
249void RuleSet::addRegionRule(StyleRuleRegion* regionRule, bool hasDocumentSecurityOrigin)
250{
251    OwnPtr<RuleSet> regionRuleSet = RuleSet::create();
252    // The region rule set should take into account the position inside the parent rule set.
253    // Otherwise, the rules inside region block might be incorrectly positioned before other similar rules from
254    // the stylesheet that contains the region block.
255    regionRuleSet->m_ruleCount = m_ruleCount;
256
257    // Collect the region rules into a rule set
258    // FIXME: Should this add other types of rules? (i.e. use addChildRules() directly?)
259    const Vector<RefPtr<StyleRuleBase> >& childRules = regionRule->childRules();
260    AddRuleFlags addRuleFlags = hasDocumentSecurityOrigin ? RuleHasDocumentSecurityOrigin : RuleHasNoSpecialState;
261    addRuleFlags = static_cast<AddRuleFlags>(addRuleFlags | RuleCanUseFastCheckSelector | RuleIsInRegionRule);
262    for (unsigned i = 0; i < childRules.size(); ++i) {
263        StyleRuleBase* regionStylingRule = childRules[i].get();
264        if (regionStylingRule->isStyleRule())
265            regionRuleSet->addStyleRule(static_cast<StyleRule*>(regionStylingRule), addRuleFlags);
266    }
267    // Update the "global" rule count so that proper order is maintained
268    m_ruleCount = regionRuleSet->m_ruleCount;
269
270    m_regionSelectorsAndRuleSets.append(RuleSetSelectorPair(regionRule->selectorList().first(), regionRuleSet.release()));
271}
272
273void RuleSet::addChildRules(const Vector<RefPtr<StyleRuleBase> >& rules, const MediaQueryEvaluator& medium, StyleResolver* resolver, const ContainerNode* scope, bool hasDocumentSecurityOrigin, AddRuleFlags addRuleFlags)
274{
275    for (unsigned i = 0; i < rules.size(); ++i) {
276        StyleRuleBase* rule = rules[i].get();
277
278        if (rule->isStyleRule()) {
279            StyleRule* styleRule = static_cast<StyleRule*>(rule);
280            addStyleRule(styleRule, addRuleFlags);
281        } else if (rule->isPageRule())
282            addPageRule(static_cast<StyleRulePage*>(rule));
283        else if (rule->isMediaRule()) {
284            StyleRuleMedia* mediaRule = static_cast<StyleRuleMedia*>(rule);
285            if ((!mediaRule->mediaQueries() || medium.eval(mediaRule->mediaQueries(), resolver)))
286                addChildRules(mediaRule->childRules(), medium, resolver, scope, hasDocumentSecurityOrigin, addRuleFlags);
287        } else if (rule->isFontFaceRule() && resolver) {
288            // Add this font face to our set.
289            // FIXME(BUG 72461): We don't add @font-face rules of scoped style sheets for the moment.
290            if (scope)
291                continue;
292            const StyleRuleFontFace* fontFaceRule = static_cast<StyleRuleFontFace*>(rule);
293            resolver->fontSelector()->addFontFaceRule(fontFaceRule);
294            resolver->invalidateMatchedPropertiesCache();
295        } else if (rule->isKeyframesRule() && resolver) {
296            // FIXME (BUG 72462): We don't add @keyframe rules of scoped style sheets for the moment.
297            if (scope)
298                continue;
299            resolver->addKeyframeStyle(static_cast<StyleRuleKeyframes*>(rule));
300        }
301#if ENABLE(CSS_REGIONS)
302        else if (rule->isRegionRule() && resolver) {
303            // FIXME (BUG 72472): We don't add @-webkit-region rules of scoped style sheets for the moment.
304            if (scope)
305                continue;
306            addRegionRule(static_cast<StyleRuleRegion*>(rule), hasDocumentSecurityOrigin);
307        }
308#endif
309#if ENABLE(SHADOW_DOM)
310        else if (rule->isHostRule())
311            resolver->addHostRule(static_cast<StyleRuleHost*>(rule), hasDocumentSecurityOrigin, scope);
312#endif
313#if ENABLE(CSS_DEVICE_ADAPTATION)
314        else if (rule->isViewportRule() && resolver) {
315            // @viewport should not be scoped.
316            if (scope)
317                continue;
318            resolver->viewportStyleResolver()->addViewportRule(static_cast<StyleRuleViewport*>(rule));
319        }
320#endif
321#if ENABLE(CSS3_CONDITIONAL_RULES)
322        else if (rule->isSupportsRule() && static_cast<StyleRuleSupports*>(rule)->conditionIsSupported())
323            addChildRules(static_cast<StyleRuleSupports*>(rule)->childRules(), medium, resolver, scope, hasDocumentSecurityOrigin, addRuleFlags);
324#endif
325    }
326}
327
328void RuleSet::addRulesFromSheet(StyleSheetContents* sheet, const MediaQueryEvaluator& medium, StyleResolver* resolver, const ContainerNode* scope)
329{
330    ASSERT(sheet);
331
332    const Vector<RefPtr<StyleRuleImport> >& importRules = sheet->importRules();
333    for (unsigned i = 0; i < importRules.size(); ++i) {
334        StyleRuleImport* importRule = importRules[i].get();
335        if (importRule->styleSheet() && (!importRule->mediaQueries() || medium.eval(importRule->mediaQueries(), resolver)))
336            addRulesFromSheet(importRule->styleSheet(), medium, resolver, scope);
337    }
338
339    bool hasDocumentSecurityOrigin = resolver && resolver->document()->securityOrigin()->canRequest(sheet->baseURL());
340    AddRuleFlags addRuleFlags = static_cast<AddRuleFlags>((hasDocumentSecurityOrigin ? RuleHasDocumentSecurityOrigin : 0) | (!scope ? RuleCanUseFastCheckSelector : 0));
341
342    addChildRules(sheet->childRules(), medium, resolver, scope, hasDocumentSecurityOrigin, addRuleFlags);
343
344    if (m_autoShrinkToFitEnabled)
345        shrinkToFit();
346}
347
348void RuleSet::addStyleRule(StyleRule* rule, AddRuleFlags addRuleFlags)
349{
350    for (size_t selectorIndex = 0; selectorIndex != notFound; selectorIndex = rule->selectorList().indexOfNextSelectorAfter(selectorIndex))
351        addRule(rule, selectorIndex, addRuleFlags);
352}
353
354static inline void shrinkMapVectorsToFit(RuleSet::AtomRuleMap& map)
355{
356    RuleSet::AtomRuleMap::iterator end = map.end();
357    for (RuleSet::AtomRuleMap::iterator it = map.begin(); it != end; ++it)
358        it->value->shrinkToFit();
359}
360
361void RuleSet::shrinkToFit()
362{
363    shrinkMapVectorsToFit(m_idRules);
364    shrinkMapVectorsToFit(m_classRules);
365    shrinkMapVectorsToFit(m_tagRules);
366    shrinkMapVectorsToFit(m_shadowPseudoElementRules);
367    m_linkPseudoClassRules.shrinkToFit();
368#if ENABLE(VIDEO_TRACK)
369    m_cuePseudoRules.shrinkToFit();
370#endif
371    m_focusPseudoClassRules.shrinkToFit();
372    m_universalRules.shrinkToFit();
373    m_pageRules.shrinkToFit();
374}
375
376} // namespace WebCore
377