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 : public DocumentSupplement { 47 public: ~CSSSelectorWatch()48 virtual ~CSSSelectorWatch() { } 49 50 static CSSSelectorWatch& from(Document&); 51 52 void watchCSSSelectors(const Vector<String>& selectors); watchedCallbackSelectors()53 const Vector<RefPtr<StyleRule> >& watchedCallbackSelectors() const { return m_watchedCallbackSelectors; } 54 55 void updateSelectorMatches(const Vector<String>& removedSelectors, const Vector<String>& addedSelectors); 56 57 private: 58 CSSSelectorWatch(Document&); 59 void callbackSelectorChangeTimerFired(Timer<CSSSelectorWatch>*); 60 61 Document& m_document; 62 63 Vector<RefPtr<StyleRule> > m_watchedCallbackSelectors; 64 65 // Maps a CSS selector string with a -webkit-callback property to the number 66 // of matching RenderStyle objects in this document. 67 HashCountedSet<String> m_matchingCallbackSelectors; 68 // Selectors are relative to m_matchingCallbackSelectors's contents at 69 // the previous call to selectorMatchChanged. 70 HashSet<String> m_addedSelectors; 71 HashSet<String> m_removedSelectors; 72 73 Timer<CSSSelectorWatch> m_callbackSelectorChangeTimer; 74 75 // When an element is reparented, the new location's style is evaluated after the expriation of the relayout timer. 76 // We don't want to send redundant callbacks to the embedder, so this counter lets us wait another time around the event loop. 77 int m_timerExpirations; 78 }; 79 80 } // namespace WebCore 81 82 #endif // CSSSelectorWatch_h 83