layout/style/nsCSSRuleProcessor.h

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   3 /* ***** BEGIN LICENSE BLOCK *****
   4  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   5  *
   6  * The contents of this file are subject to the Mozilla Public License Version
   7  * 1.1 (the "License"); you may not use this file except in compliance with
   8  * the License. You may obtain a copy of the License at
   9  * http://www.mozilla.org/MPL/
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  11  * Software distributed under the License is distributed on an "AS IS" basis,
  12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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  15  *
  16  * The Original Code is mozilla.org code.
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  18  * The Initial Developer of the Original Code is
  19  * Netscape Communications Corporation.
  20  * Portions created by the Initial Developer are Copyright (C) 1998
  21  * the Initial Developer. All Rights Reserved.
  22  *
  23  * Contributor(s):
  24  *   L. David Baron <dbaron@dbaron.org>
  25  *
  26  * Alternatively, the contents of this file may be used under the terms of
  27  * either of the GNU General Public License Version 2 or later (the "GPL"),
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  37  *
  38  * ***** END LICENSE BLOCK ***** */
  39
  40 /*
  41  * style rule processor for CSS style sheets, responsible for selector
  42  * matching and cascading
  43  */
  44
  45 #ifndef nsCSSRuleProcessor_h_
  46 #define nsCSSRuleProcessor_h_
  47
  48 #include "nsIStyleRuleProcessor.h"
  49 #include "nsCSSStyleSheet.h"
  50 #include "nsTArray.h"
  51 #include "nsAutoPtr.h"
  52 #include "nsCSSRules.h"
  53
  54 struct RuleCascadeData;
  55 struct nsCSSSelectorList;
  56 struct CascadeEnumData;
  57
  58 /**
  59  * The CSS style rule processor provides a mechanism for sibling style
  60  * sheets to combine their rule processing in order to allow proper
  61  * cascading to happen.
  62  *
  63  * CSS style rule processors keep a live reference on all style sheets
  64  * bound to them.  The CSS style sheets keep a weak reference to all the
  65  * processors that they are bound to (many to many).  The CSS style sheet
  66  * is told when the rule processor is going away (via DropRuleProcessor).
  67  */
  68
  69 class nsCSSRuleProcessor: public nsIStyleRuleProcessor {
  70 public:
  71   typedef nsTArray<nsRefPtr<nsCSSStyleSheet> > sheet_array_type;
  72
  73   nsCSSRuleProcessor(const sheet_array_type& aSheets, PRUint8 aSheetType);
  74   virtual ~nsCSSRuleProcessor();
  75
  76   NS_DECL_ISUPPORTS
  77
  78 public:
  79   nsresult ClearRuleCascades();
  80
  81   static nsresult Startup();
  82   static void Shutdown();
  83   static void FreeSystemMetrics();
  84   static PRBool HasSystemMetric(nsIAtom* aMetric);
  85
  86   /*
  87    * Returns true if the given RuleProcessorData matches one of the
  88    * selectors in aSelectorList.  Note that this method will assume
  89    * the matching is not for styling purposes.  aSelectorList must not
  90    * include any pseudo-element selectors.  aSelectorList is allowed
  91    * to be null; in this case PR_FALSE will be returned.
  92    */
  93   static PRBool SelectorListMatches(RuleProcessorData& aData,
  94                                     nsCSSSelectorList* aSelectorList);
  95
  96   // nsIStyleRuleProcessor
  97   virtual void RulesMatching(ElementRuleProcessorData* aData);
  98
  99   virtual void RulesMatching(PseudoElementRuleProcessorData* aData);
 100
 101   virtual void RulesMatching(AnonBoxRuleProcessorData* aData);
 102
 103 #ifdef MOZ_XUL
 104   virtual void RulesMatching(XULTreeRuleProcessorData* aData);
 105 #endif
 106
 107   virtual nsRestyleHint HasStateDependentStyle(StateRuleProcessorData* aData);
 108
 109   virtual PRBool HasDocumentStateDependentStyle(StateRuleProcessorData* aData);
 110
 111   virtual nsRestyleHint
 112     HasAttributeDependentStyle(AttributeRuleProcessorData* aData);
 113
 114   virtual PRBool MediumFeaturesChanged(nsPresContext* aPresContext);
 115
 116   // Append all the currently-active font face rules to aArray.  Return
 117   // true for success and false for failure.
 118   PRBool AppendFontFaceRules(nsPresContext* aPresContext,
 119                              nsTArray<nsFontFaceRuleContainer>& aArray);
 120
 121 #ifdef DEBUG
 122   void AssertQuirksChangeOK() {
 123     NS_ASSERTION(!mRuleCascades, "can't toggle quirks style sheet without "
 124                                  "clearing rule cascades");
 125   }
 126 #endif
 127
 128 #ifdef XP_WIN
 129   // Cached theme identifier for the moz-windows-theme media query.
 130   static PRUint8 GetWindowsThemeIdentifier();
 131   static void SetWindowsThemeIdentifier(PRUint8 aId) {
 132     sWinThemeId = aId;
 133   }
 134 #endif
 135
 136 private:
 137   static PRBool CascadeSheet(nsCSSStyleSheet* aSheet, CascadeEnumData* aData);
 138
 139   RuleCascadeData* GetRuleCascade(nsPresContext* aPresContext);
 140   void RefreshRuleCascade(nsPresContext* aPresContext);
 141
 142   // The sheet order here is the same as in nsStyleSet::mSheets
 143   sheet_array_type mSheets;
 144
 145   // active first, then cached (most recent first)
 146   RuleCascadeData* mRuleCascades;
 147
 148   // The last pres context for which GetRuleCascades was called.
 149   nsPresContext *mLastPresContext;
 150
 151   // type of stylesheet using this processor
 152   PRUint8 mSheetType;  // == nsStyleSet::sheetType
 153
 154 #ifdef XP_WIN
 155   static PRUint8 sWinThemeId;
 156 #endif
 157 };
 158
 159 #endif /* nsCSSRuleProcessor_h_ */