1 /* 2 * Copyright (C) 2013 Google, Inc. 3 * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org) 4 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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 #ifndef SharedStyleFinder_h 23 #define SharedStyleFinder_h 24 25 #include "core/css/resolver/ElementResolveContext.h" 26 #include "core/dom/Element.h" 27 28 namespace WebCore { 29 30 class Element; 31 class Node; 32 class RenderStyle; 33 class RuleFeatureSet; 34 class RuleSet; 35 class SpaceSplitString; 36 class StyleResolver; 37 38 class SharedStyleFinder { 39 STACK_ALLOCATED(); 40 public: 41 // RuleSets are passed non-const as the act of matching against them can cause them 42 // to be compacted. :( 43 SharedStyleFinder(const ElementResolveContext& context, 44 const RuleFeatureSet& features, RuleSet* siblingRuleSet, 45 RuleSet* uncommonAttributeRuleSet, StyleResolver& styleResolver) 46 : m_elementAffectedByClassRules(false) 47 , m_features(features) 48 , m_siblingRuleSet(siblingRuleSet) 49 , m_uncommonAttributeRuleSet(uncommonAttributeRuleSet) 50 , m_styleResolver(styleResolver) 51 , m_context(context) 52 { } 53 54 RenderStyle* findSharedStyle(); 55 56 private: 57 Element* findElementForStyleSharing() const; 58 59 // Only used when we're collecting stats on styles. 60 bool documentContainsValidCandidate() const; 61 62 bool classNamesAffectedByRules(const SpaceSplitString&) const; 63 64 bool canShareStyleWithElement(Element& candidate) const; 65 bool canShareStyleWithControl(Element& candidate) const; 66 bool sharingCandidateHasIdenticalStyleAffectingAttributes(Element& candidate) const; 67 bool sharingCandidateCanShareHostStyles(Element& candidate) const; 68 bool sharingCandidateDistributedToSameInsertionPoint(Element& candidate) const; 69 bool matchesRuleSet(RuleSet*); 70 71 Element& element() const { return *m_context.element(); } 72 Document& document() const { return element().document(); } 73 74 bool m_elementAffectedByClassRules; 75 const RuleFeatureSet& m_features; 76 RawPtrWillBeMember<RuleSet> m_siblingRuleSet; 77 RawPtrWillBeMember<RuleSet> m_uncommonAttributeRuleSet; 78 StyleResolver& m_styleResolver; 79 const ElementResolveContext& m_context; 80 }; 81 82 } // namespace WebCore 83 84 #endif // SharedStyleFinder_h 85