1 /* 2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org) 3 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved. 4 * Copyright (C) 2013 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 MatchedPropertiesCache_h 24 #define MatchedPropertiesCache_h 25 26 #include "core/css/resolver/MatchResult.h" 27 28 #include "platform/Timer.h" 29 #include "wtf/Forward.h" 30 #include "wtf/HashMap.h" 31 #include "wtf/Noncopyable.h" 32 33 namespace WebCore { 34 35 class RenderStyle; 36 class StyleResolverState; 37 38 struct CachedMatchedProperties { 39 Vector<MatchedProperties> matchedProperties; 40 MatchRanges ranges; 41 RefPtr<RenderStyle> renderStyle; 42 RefPtr<RenderStyle> parentRenderStyle; 43 44 void set(const RenderStyle*, const RenderStyle* parentStyle, const MatchResult&); 45 void clear(); 46 }; 47 48 class MatchedPropertiesCache { 49 WTF_MAKE_NONCOPYABLE(MatchedPropertiesCache); 50 public: 51 MatchedPropertiesCache(); 52 53 const CachedMatchedProperties* find(unsigned hash, const StyleResolverState&, const MatchResult&); 54 void add(const RenderStyle*, const RenderStyle* parentStyle, unsigned hash, const MatchResult&); 55 56 void clear(); 57 58 static bool isCacheable(const Element*, const RenderStyle*, const RenderStyle* parentStyle); 59 60 private: 61 // Every N additions to the matched declaration cache trigger a sweep where entries holding 62 // the last reference to a style declaration are garbage collected. 63 void sweep(Timer<MatchedPropertiesCache>*); 64 65 unsigned m_additionsSinceLastSweep; 66 67 typedef HashMap<unsigned, OwnPtr<CachedMatchedProperties> > Cache; 68 Cache m_cache; 69 70 Timer<MatchedPropertiesCache> m_sweepTimer; 71 }; 72 73 } 74 75 #endif 76