layout/style/nsCSSDeclaration.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Daniel Glazman <glazman@netscape.com>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either of the GNU General Public License Version 2 or later (the "GPL"),
  27  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
  30  * under the terms of either the GPL or the LGPL, and not to allow others to
  31  * use your version of this file under the terms of the MPL, indicate your
  32  * decision by deleting the provisions above and replace them with the notice
  33  * and other provisions required by the GPL or the LGPL. If you do not delete
  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 /*
  40  * representation of a declaration block (or style attribute) in a CSS
  41  * stylesheet
  42  */
  43
  44 #ifndef nsCSSDeclaration_h___
  45 #define nsCSSDeclaration_h___
  46
  47 #include "nsISupports.h"
  48 #include "nsColor.h"
  49 #include <stdio.h>
  50 #include "nsString.h"
  51 #include "nsCoord.h"
  52 #include "nsCSSValue.h"
  53 #include "nsCSSProps.h"
  54 #include "nsTArray.h"
  55 #include "nsCSSDataBlock.h"
  56 #include "nsCSSStruct.h"
  57
  58 class nsCSSDeclaration {
  59 public:
  60   /**
  61    * Construct an |nsCSSDeclaration| that is in an invalid state (null
  62    * |mData|) and cannot be used until its |CompressFrom| method or
  63    * |InitializeEmpty| method is called.
  64    */
  65   nsCSSDeclaration();
  66
  67   nsCSSDeclaration(const nsCSSDeclaration& aCopy);
  68
  69   /**
  70    * |ValueAppended| must be called to maintain this declaration's
  71    * |mOrder| whenever a property is parsed into an expanded data block
  72    * for this declaration.
  73    */
  74   nsresult ValueAppended(nsCSSProperty aProperty);
  75
  76   nsresult AppendComment(const nsAString& aComment);
  77   nsresult RemoveProperty(nsCSSProperty aProperty);
  78
  79   nsresult GetValue(nsCSSProperty aProperty, nsAString& aValue) const;
  80   nsresult GetValue(const nsAString& aProperty, nsAString& aValue) const;
  81
  82   PRBool HasImportantData() const { return mImportantData != nsnull; }
  83   PRBool GetValueIsImportant(nsCSSProperty aProperty) const;
  84   PRBool GetValueIsImportant(const nsAString& aProperty) const;
  85
  86   PRUint32 Count() const {
  87     return mOrder.Length();
  88   }
  89   nsresult GetNthProperty(PRUint32 aIndex, nsAString& aReturn) const;
  90
  91   nsresult ToString(nsAString& aString) const;
  92
  93   nsCSSDeclaration* Clone() const;
  94
  95   nsresult MapRuleInfoInto(nsRuleData *aRuleData) const {
  96     return mData->MapRuleInfoInto(aRuleData);
  97   }
  98
  99   nsresult MapImportantRuleInfoInto(nsRuleData *aRuleData) const {
 100     return mImportantData->MapRuleInfoInto(aRuleData);
 101   }
 102
 103   /**
 104    * Initialize this declaration as holding no data.  Return false on
 105    * out-of-memory.
 106    */
 107   PRBool InitializeEmpty();
 108
 109   /**
 110    * Transfer all of the state from |aExpandedData| into this declaration.
 111    * After calling, |aExpandedData| should be in its initial state.
 112    */
 113   void CompressFrom(nsCSSExpandedDataBlock *aExpandedData) {
 114     NS_ASSERTION(!mData, "oops");
 115     NS_ASSERTION(!mImportantData, "oops");
 116     aExpandedData->Compress(&mData, &mImportantData);
 117   }
 118
 119   /**
 120    * Transfer all of the state from this declaration into
 121    * |aExpandedData| and put this declaration temporarily into an
 122    * invalid state (ended by |CompressFrom| or |InitializeEmpty|) that
 123    * should last only during parsing.  During this time only
 124    * |ValueAppended| should be called.
 125    */
 126   void ExpandTo(nsCSSExpandedDataBlock *aExpandedData) {
 127     aExpandedData->AssertInitialState();
 128
 129     NS_ASSERTION(mData, "oops");
 130     aExpandedData->Expand(&mData, &mImportantData);
 131     NS_ASSERTION(!mData && !mImportantData,
 132                  "Expand didn't null things out");
 133   }
 134
 135   /**
 136    * Clear the data, in preparation for its replacement with entirely
 137    * new data by a call to |CompressFrom|.
 138    */
 139   void ClearData() {
 140     mData->Destroy();
 141     mData = nsnull;
 142     if (mImportantData) {
 143       mImportantData->Destroy();
 144       mImportantData = nsnull;
 145     }
 146     mOrder.Clear();
 147   }
 148
 149 #ifdef DEBUG
 150   void List(FILE* out = stdout, PRInt32 aIndent = 0) const;
 151 #endif
 152
 153   // return whether there was a value in |aValue| (i.e., it had a non-null unit)
 154   static PRBool AppendCSSValueToString(nsCSSProperty aProperty,
 155                                        const nsCSSValue& aValue,
 156                                        nsAString& aResult);
 157
 158 private:
 159   // Not implemented, and not supported.
 160   nsCSSDeclaration& operator=(const nsCSSDeclaration& aCopy);
 161   PRBool operator==(const nsCSSDeclaration& aCopy) const;
 162
 163   static void AppendImportanceToString(PRBool aIsImportant, nsAString& aString);
 164   // return whether there was a value in |aValue| (i.e., it had a non-null unit)
 165   PRBool   AppendValueToString(nsCSSProperty aProperty, nsAString& aResult) const;
 166   // May be called only for properties whose type is eCSSType_Value.
 167   nsresult GetValueOrImportantValue(nsCSSProperty aProperty, nsCSSValue& aValue) const;
 168
 169   void   PropertyIsSet(PRInt32 & aPropertyIndex, PRInt32 aIndex, PRUint32 & aSet, PRUint32 aValue) const;
 170   PRBool TryBorderShorthand(nsAString & aString, PRUint32 aPropertiesSet,
 171                             PRInt32 aBorderTopWidth,
 172                             PRInt32 aBorderTopStyle,
 173                             PRInt32 aBorderTopColor,
 174                             PRInt32 aBorderBottomWidth,
 175                             PRInt32 aBorderBottomStyle,
 176                             PRInt32 aBorderBottomColor,
 177                             PRInt32 aBorderLeftWidth,
 178                             PRInt32 aBorderLeftStyle,
 179                             PRInt32 aBorderLeftColor,
 180                             PRInt32 aBorderRightWidth,
 181                             PRInt32 aBorderRightStyle,
 182                             PRInt32 aBorderRightColor) const;
 183   PRBool  TryBorderSideShorthand(nsAString & aString,
 184                                  nsCSSProperty  aShorthand,
 185                                  PRInt32 aBorderWidth,
 186                                  PRInt32 aBorderStyle,
 187                                  PRInt32 aBorderColor) const;
 188   PRBool  TryFourSidesShorthand(nsAString & aString,
 189                                 nsCSSProperty aShorthand,
 190                                 PRInt32 & aTop,
 191                                 PRInt32 & aBottom,
 192                                 PRInt32 & aLeft,
 193                                 PRInt32 & aRight,
 194                                 PRBool aClearIndexes) const;
 195   void  TryBackgroundShorthand(nsAString & aString,
 196                                PRInt32 & aBgColor, PRInt32 & aBgImage,
 197                                PRInt32 & aBgRepeat, PRInt32 & aBgAttachment,
 198                                PRInt32 & aBgPosition) const;
 199   void  TryOverflowShorthand(nsAString & aString,
 200                              PRInt32 & aOverflowX, PRInt32 & aOverflowY) const;
 201 #ifdef MOZ_SVG
 202   void  TryMarkerShorthand(nsAString & aString,
 203                            PRInt32 & aMarkerEnd,
 204                            PRInt32 & aMarkerMid,
 205                            PRInt32 & aMarkerStart) const;
 206 #endif
 207
 208   PRBool   AllPropertiesSameImportance(PRInt32 aFirst, PRInt32 aSecond,
 209                                        PRInt32 aThird, PRInt32 aFourth,
 210                                        PRInt32 aFifth,
 211                                        PRBool & aImportance) const;
 212   PRBool   AllPropertiesSameValue(PRInt32 aFirst, PRInt32 aSecond,
 213                                   PRInt32 aThird, PRInt32 aFourth) const;
 214   void     AppendPropertyAndValueToString(nsCSSProperty aProperty,
 215                                           nsAString& aResult) const
 216   {
 217     AppendPropertyAndValueToString(aProperty, aProperty, aResult);
 218   }
 219   void     AppendPropertyAndValueToString(nsCSSProperty aProperty,
 220                                           nsCSSProperty aPropertyName,
 221                                           nsAString& aResult) const;
 222
 223 private:
 224     //
 225     // Specialized ref counting.
 226     // We do not want everyone to ref count us, only the rules which hold
 227     //  onto us (our well defined lifetime is when the last rule releases
 228     //  us).
 229     // It's worth a comment here that the main nsCSSDeclaration is refcounted,
 230     //  but it's |mImportant| is not refcounted, but just owned by the
 231     //  non-important declaration.
 232     //
 233     friend class CSSStyleRuleImpl;
 234     void AddRef(void) {
 235       ++mRefCnt;
 236     }
 237     void Release(void) {
 238       NS_ASSERTION(0 < mRefCnt, "bad Release");
 239       if (0 == --mRefCnt) {
 240         delete this;
 241       }
 242     }
 243 public:
 244     void RuleAbort(void) {
 245       NS_ASSERTION(0 == mRefCnt, "bad RuleAbort");
 246       delete this;
 247     }
 248 private:
 249   // Block everyone, except us or a derivative, from deleting us.
 250   ~nsCSSDeclaration(void);
 251
 252   nsCSSProperty OrderValueAt(PRUint32 aValue) const {
 253     return nsCSSProperty(mOrder.ElementAt(aValue));
 254   }
 255
 256 private:
 257     nsAutoTArray<PRUint8, 8> mOrder;
 258     nsAutoRefCnt mRefCnt;
 259     nsCSSCompressedDataBlock *mData; // never null, except while expanded
 260     nsCSSCompressedDataBlock *mImportantData; // may be null
 261 };
 262
 263 #endif /* nsCSSDeclaration_h___ */