1 /* 2 * Copyright (C) 2013 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef CSSSelectorWatch_h 32 #define CSSSelectorWatch_h 33 34 #include "core/css/StyleRule.h" 35 #include "core/dom/DocumentSupplementable.h" 36 #include "platform/Timer.h" 37 #include "wtf/HashCountedSet.h" 38 #include "wtf/HashSet.h" 39 #include "wtf/RefPtr.h" 40 #include "wtf/Vector.h" 41 #include "wtf/WeakPtr.h" 42 #include "wtf/text/WTFString.h" 43 44 namespace WebCore { 45 46 class CSSSelectorWatch FINAL : public NoBaseWillBeGarbageCollectedFinalized<CSSSelectorWatch>, public DocumentSupplement { 47 WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(CSSSelectorWatch); 48 public: ~CSSSelectorWatch()49 virtual ~CSSSelectorWatch() { } 50 51 static CSSSelectorWatch& from(Document&); 52 53 void watchCSSSelectors(const Vector<String>& selectors); watchedCallbackSelectors()54 const WillBeHeapVector<RefPtrWillBeMember<StyleRule> >& watchedCallbackSelectors() const { return m_watchedCallbackSelectors; } 55 56 void updateSelectorMatches(const Vector<String>& removedSelectors, const Vector<String>& addedSelectors); 57 58 virtual void trace(Visitor*) OVERRIDE; 59 60 private: 61 explicit CSSSelectorWatch(Document&); 62 void callbackSelectorChangeTimerFired(Timer<CSSSelectorWatch>*); 63 64 Document& m_document; 65 66 WillBeHeapVector<RefPtrWillBeMember<StyleRule> > m_watchedCallbackSelectors; 67 68 // Maps a CSS selector string with a -webkit-callback property to the number 69 // of matching RenderStyle objects in this document. 70 HashCountedSet<String> m_matchingCallbackSelectors; 71 // Selectors are relative to m_matchingCallbackSelectors's contents at 72 // the previous call to selectorMatchChanged. 73 HashSet<String> m_addedSelectors; 74 HashSet<String> m_removedSelectors; 75 76 Timer<CSSSelectorWatch> m_callbackSelectorChangeTimer; 77 78 // When an element is reparented, the new location's style is evaluated after the expriation of the relayout timer. 79 // We don't want to send redundant callbacks to the embedder, so this counter lets us wait another time around the event loop. 80 int m_timerExpirations; 81 }; 82 83 } // namespace WebCore 84 85 #endif // CSSSelectorWatch_h 86