content/base/src/nsAttrValue.h

Thu, 15 Jan 2015 21:03:48 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Thu, 15 Jan 2015 21:03:48 +0100
branch
TOR_BUG_9701
changeset 11
deefc01c0e14
permissions
-rw-r--r--

Integrate friendly tips from Tor colleagues to make (or not) 4.5 alpha 3;
This includes removal of overloaded (but unused) methods, and addition of
a overlooked call to DataStruct::SetData(nsISupports, uint32_t, bool.)

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
     2 /* This Source Code Form is subject to the terms of the Mozilla Public
     3  * License, v. 2.0. If a copy of the MPL was not distributed with this
     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
     6 /*
     7  * A struct that represents the value (type and actual data) of an
     8  * attribute.
     9  */
    11 #ifndef nsAttrValue_h___
    12 #define nsAttrValue_h___
    14 #include "nscore.h"
    15 #include "nsStringGlue.h"
    16 #include "nsStringBuffer.h"
    17 #include "nsColor.h"
    18 #include "nsCaseTreatment.h"
    19 #include "nsMargin.h"
    20 #include "nsCOMPtr.h"
    21 #include "SVGAttrValueWrapper.h"
    22 #include "nsTArrayForwardDeclare.h"
    23 #include "nsIAtom.h"
    24 #include "mozilla/MemoryReporting.h"
    25 #include "mozilla/dom/BindingDeclarations.h"
    27 class nsAString;
    28 class nsIDocument;
    29 class nsStyledElementNotElementCSSInlineStyle;
    30 struct MiscContainer;
    32 namespace mozilla {
    33 namespace css {
    34 class StyleRule;
    35 struct URLValue;
    36 struct ImageValue;
    37 }
    38 }
    40 #define NS_ATTRVALUE_MAX_STRINGLENGTH_ATOM 12
    42 #define NS_ATTRVALUE_BASETYPE_MASK (uintptr_t(3))
    43 #define NS_ATTRVALUE_POINTERVALUE_MASK (~NS_ATTRVALUE_BASETYPE_MASK)
    45 #define NS_ATTRVALUE_INTEGERTYPE_BITS 4
    46 #define NS_ATTRVALUE_INTEGERTYPE_MASK (uintptr_t((1 << NS_ATTRVALUE_INTEGERTYPE_BITS) - 1))
    47 #define NS_ATTRVALUE_INTEGERTYPE_MULTIPLIER (1 << NS_ATTRVALUE_INTEGERTYPE_BITS)
    48 #define NS_ATTRVALUE_INTEGERTYPE_MAXVALUE ((1 << (31 - NS_ATTRVALUE_INTEGERTYPE_BITS)) - 1)
    49 #define NS_ATTRVALUE_INTEGERTYPE_MINVALUE (-NS_ATTRVALUE_INTEGERTYPE_MAXVALUE - 1)
    51 #define NS_ATTRVALUE_ENUMTABLEINDEX_BITS (32 - 16 - NS_ATTRVALUE_INTEGERTYPE_BITS)
    52 #define NS_ATTRVALUE_ENUMTABLE_VALUE_NEEDS_TO_UPPER (1 << (NS_ATTRVALUE_ENUMTABLEINDEX_BITS - 1))
    53 #define NS_ATTRVALUE_ENUMTABLEINDEX_MAXVALUE (NS_ATTRVALUE_ENUMTABLE_VALUE_NEEDS_TO_UPPER - 1)
    54 #define NS_ATTRVALUE_ENUMTABLEINDEX_MASK \
    55   (uintptr_t((((1 << NS_ATTRVALUE_ENUMTABLEINDEX_BITS) - 1) &~ NS_ATTRVALUE_ENUMTABLE_VALUE_NEEDS_TO_UPPER)))
    57 /**
    58  * A class used to construct a nsString from a nsStringBuffer (we might
    59  * want to move this to nsString at some point).
    60  *
    61  * WARNING: Note that nsCheapString doesn't take an explicit length -- it
    62  * assumes the string is maximally large, given the nsStringBuffer's storage
    63  * size.  This means the given string buffer *must* be sized exactly correctly
    64  * for the string it contains (including one byte for a null terminator).  If
    65  * it has any unused storage space, then that will result in bogus characters
    66  * at the end of our nsCheapString.
    67  */
    68 class nsCheapString : public nsString {
    69 public:
    70   nsCheapString(nsStringBuffer* aBuf)
    71   {
    72     if (aBuf)
    73       aBuf->ToString(aBuf->StorageSize()/sizeof(char16_t) - 1, *this);
    74   }
    75 };
    77 class nsAttrValue {
    78   friend struct MiscContainer;
    79 public:
    80   typedef nsTArray< nsCOMPtr<nsIAtom> > AtomArray;
    82   // This has to be the same as in ValueBaseType
    83   enum ValueType {
    84     eString =       0x00, //   00
    85                           //   01  this value indicates an 'misc' struct
    86     eAtom =         0x02, //   10
    87     eInteger =      0x03, // 0011
    88     eColor =        0x07, // 0111
    89     eEnum =         0x0B, // 1011  This should eventually die
    90     ePercent =      0x0F, // 1111
    91     // Values below here won't matter, they'll be always stored in the 'misc'
    92     // struct.
    93     eCSSStyleRule =            0x10
    94     ,eURL =                    0x11
    95     ,eImage =                  0x12
    96     ,eAtomArray =              0x13
    97     ,eDoubleValue  =           0x14
    98     ,eIntMarginValue =         0x15
    99     ,eSVGAngle =               0x16
   100     ,eSVGTypesBegin =          eSVGAngle
   101     ,eSVGIntegerPair =         0x17
   102     ,eSVGLength =              0x18
   103     ,eSVGLengthList =          0x19
   104     ,eSVGNumberList =          0x1A
   105     ,eSVGNumberPair =          0x1B
   106     ,eSVGPathData =            0x1C
   107     ,eSVGPointList =           0x1D
   108     ,eSVGPreserveAspectRatio = 0x1E
   109     ,eSVGStringList =          0x1F
   110     ,eSVGTransformList =       0x20
   111     ,eSVGViewBox =             0x21
   112     ,eSVGTypesEnd =            eSVGViewBox
   113   };
   115   nsAttrValue();
   116   nsAttrValue(const nsAttrValue& aOther);
   117   explicit nsAttrValue(const nsAString& aValue);
   118   explicit nsAttrValue(nsIAtom* aValue);
   119   nsAttrValue(mozilla::css::StyleRule* aValue, const nsAString* aSerialized);
   120   explicit nsAttrValue(const nsIntMargin& aValue);
   121   ~nsAttrValue();
   123   inline const nsAttrValue& operator=(const nsAttrValue& aOther);
   125   static nsresult Init();
   126   static void Shutdown();
   128   ValueType Type() const;
   130   void Reset();
   132   void SetTo(const nsAttrValue& aOther);
   133   void SetTo(const nsAString& aValue);
   134   void SetTo(nsIAtom* aValue);
   135   void SetTo(int16_t aInt);
   136   void SetTo(int32_t aInt, const nsAString* aSerialized);
   137   void SetTo(double aValue, const nsAString* aSerialized);
   138   void SetTo(mozilla::css::StyleRule* aValue, const nsAString* aSerialized);
   139   void SetTo(mozilla::css::URLValue* aValue, const nsAString* aSerialized);
   140   void SetTo(const nsIntMargin& aValue);
   141   void SetTo(const nsSVGAngle& aValue, const nsAString* aSerialized);
   142   void SetTo(const nsSVGIntegerPair& aValue, const nsAString* aSerialized);
   143   void SetTo(const nsSVGLength2& aValue, const nsAString* aSerialized);
   144   void SetTo(const mozilla::SVGLengthList& aValue,
   145              const nsAString* aSerialized);
   146   void SetTo(const mozilla::SVGNumberList& aValue,
   147              const nsAString* aSerialized);
   148   void SetTo(const nsSVGNumberPair& aValue, const nsAString* aSerialized);
   149   void SetTo(const mozilla::SVGPathData& aValue, const nsAString* aSerialized);
   150   void SetTo(const mozilla::SVGPointList& aValue, const nsAString* aSerialized);
   151   void SetTo(const mozilla::SVGAnimatedPreserveAspectRatio& aValue,
   152              const nsAString* aSerialized);
   153   void SetTo(const mozilla::SVGStringList& aValue,
   154              const nsAString* aSerialized);
   155   void SetTo(const mozilla::SVGTransformList& aValue,
   156              const nsAString* aSerialized);
   157   void SetTo(const nsSVGViewBox& aValue, const nsAString* aSerialized);
   159   /**
   160    * Sets this object with the string or atom representation of aValue.
   161    *
   162    * After calling this method, this object will have type eString unless the
   163    * type of aValue is eAtom, in which case this object will also have type
   164    * eAtom.
   165    */
   166   void SetToSerialized(const nsAttrValue& aValue);
   168   void SwapValueWith(nsAttrValue& aOther);
   170   void ToString(nsAString& aResult) const;
   171   inline void ToString(mozilla::dom::DOMString& aResult) const;
   173   /**
   174    * Returns the value of this object as an atom. If necessary, the value will
   175    * first be serialised using ToString before converting to an atom.
   176    */
   177   already_AddRefed<nsIAtom> GetAsAtom() const;
   179   // Methods to get value. These methods do not convert so only use them
   180   // to retrieve the datatype that this nsAttrValue has.
   181   inline bool IsEmptyString() const;
   182   const nsCheapString GetStringValue() const;
   183   inline nsIAtom* GetAtomValue() const;
   184   inline int32_t GetIntegerValue() const;
   185   bool GetColorValue(nscolor& aColor) const;
   186   inline int16_t GetEnumValue() const;
   187   inline float GetPercentValue() const;
   188   inline AtomArray* GetAtomArrayValue() const;
   189   inline mozilla::css::StyleRule* GetCSSStyleRuleValue() const;
   190   inline mozilla::css::URLValue* GetURLValue() const;
   191   inline mozilla::css::ImageValue* GetImageValue() const;
   192   inline double GetDoubleValue() const;
   193   bool GetIntMarginValue(nsIntMargin& aMargin) const;
   195   /**
   196    * Returns the string corresponding to the stored enum value.
   197    *
   198    * @param aResult   the string representing the enum tag
   199    * @param aRealTag  wheter we want to have the real tag or the saved one
   200    */
   201   void GetEnumString(nsAString& aResult, bool aRealTag) const;
   203   // Methods to get access to atoms we may have
   204   // Returns the number of atoms we have; 0 if we have none.  It's OK
   205   // to call this without checking the type first; it handles that.
   206   uint32_t GetAtomCount() const;
   207   // Returns the atom at aIndex (0-based).  Do not call this with
   208   // aIndex >= GetAtomCount().
   209   nsIAtom* AtomAt(int32_t aIndex) const;
   211   uint32_t HashValue() const;
   212   bool Equals(const nsAttrValue& aOther) const;
   213   // aCaseSensitive == eIgnoreCase means ASCII case-insenstive matching
   214   bool Equals(const nsAString& aValue, nsCaseTreatment aCaseSensitive) const;
   215   bool Equals(nsIAtom* aValue, nsCaseTreatment aCaseSensitive) const;
   217   /**
   218    * Compares this object with aOther according to their string representation.
   219    *
   220    * For example, when called on an object with type eInteger and value 4, and
   221    * given aOther of type eString and value "4", EqualsAsStrings will return
   222    * true (while Equals will return false).
   223    */
   224   bool EqualsAsStrings(const nsAttrValue& aOther) const;
   226   /**
   227    * Returns true if this AttrValue is equal to the given atom, or is an
   228    * array which contains the given atom.
   229    */
   230   bool Contains(nsIAtom* aValue, nsCaseTreatment aCaseSensitive) const;
   231   /**
   232    * Returns true if this AttrValue is an atom equal to the given
   233    * string, or is an array of atoms which contains the given string.
   234    * This always does a case-sensitive comparison.
   235    */
   236   bool Contains(const nsAString& aValue) const;
   238   void ParseAtom(const nsAString& aValue);
   239   void ParseAtomArray(const nsAString& aValue);
   240   void ParseStringOrAtom(const nsAString& aValue);
   242   /**
   243    * Structure for a mapping from int (enum) values to strings.  When you use
   244    * it you generally create an array of them.
   245    * Instantiate like this:
   246    * EnumTable myTable[] = {
   247    *   { "string1", 1 },
   248    *   { "string2", 2 },
   249    *   { 0 }
   250    * }
   251    */
   252   struct EnumTable {
   253     /** The string the value maps to */
   254     const char* tag;
   255     /** The enum value that maps to this string */
   256     int16_t value;
   257   };
   259   /**
   260    * Parse into an enum value.
   261    *
   262    * @param aValue the string to find the value for
   263    * @param aTable the enumeration to map with
   264    * @param aCaseSensitive specify if the parsing has to be case sensitive
   265    * @param aDefaultValue if non-null, this function will always return true.
   266    *        Failure to parse aValue as one of the values in aTable will just
   267    *        cause aDefaultValue->value to be stored as the enumeration value.
   268    * @return whether the enum value was found or not
   269    */
   270   bool ParseEnumValue(const nsAString& aValue,
   271                         const EnumTable* aTable,
   272                         bool aCaseSensitive,
   273                         const EnumTable* aDefaultValue = nullptr);
   275   /**
   276    * Parse a string into an integer. Can optionally parse percent (n%).
   277    * This method explicitly sets a lower bound of zero on the element,
   278    * whether it be percent or raw integer.
   279    *
   280    * @param aString the string to parse
   281    * @return whether the value could be parsed
   282    *
   283    * @see http://www.whatwg.org/html/#rules-for-parsing-dimension-values
   284    */
   285   bool ParseSpecialIntValue(const nsAString& aString);
   288   /**
   289    * Parse a string value into an integer.
   290    *
   291    * @param aString the string to parse
   292    * @return whether the value could be parsed
   293    */
   294   bool ParseIntValue(const nsAString& aString) {
   295     return ParseIntWithBounds(aString, INT32_MIN, INT32_MAX);
   296   }
   298   /**
   299    * Parse a string value into an integer with minimum value and maximum value.
   300    *
   301    * @param aString the string to parse
   302    * @param aMin the minimum value (if value is less it will be bumped up)
   303    * @param aMax the maximum value (if value is greater it will be chopped down)
   304    * @return whether the value could be parsed
   305    */
   306   bool ParseIntWithBounds(const nsAString& aString, int32_t aMin,
   307                             int32_t aMax = INT32_MAX);
   309   /**
   310    * Parse a string value into a non-negative integer.
   311    * This method follows the rules for parsing non-negative integer from:
   312    * http://dev.w3.org/html5/spec/infrastructure.html#rules-for-parsing-non-negative-integers
   313    *
   314    * @param  aString the string to parse
   315    * @return whether the value is valid
   316    */
   317   bool ParseNonNegativeIntValue(const nsAString& aString);
   319   /**
   320    * Parse a string value into a positive integer.
   321    * This method follows the rules for parsing non-negative integer from:
   322    * http://dev.w3.org/html5/spec/infrastructure.html#rules-for-parsing-non-negative-integers
   323    * In addition of these rules, the value has to be greater than zero.
   324    *
   325    * This is generally used for parsing content attributes which reflecting IDL
   326    * attributes are limited to only non-negative numbers greater than zero, see:
   327    * http://dev.w3.org/html5/spec/common-dom-interfaces.html#limited-to-only-non-negative-numbers-greater-than-zero
   328    *
   329    * @param aString       the string to parse
   330    * @return              whether the value was valid
   331    */
   332   bool ParsePositiveIntValue(const nsAString& aString);
   334   /**
   335    * Parse a string into a color.  This implements what HTML5 calls the
   336    * "rules for parsing a legacy color value".
   337    *
   338    * @param aString the string to parse
   339    * @return whether the value could be parsed
   340    */
   341   bool ParseColor(const nsAString& aString);
   343   /**
   344    * Parse a string value into a double-precision floating point value.
   345    *
   346    * @param aString the string to parse
   347    * @return whether the value could be parsed
   348    */
   349   bool ParseDoubleValue(const nsAString& aString);
   351   /**
   352    * Parse a lazy URI.  This just sets up the storage for the URI; it
   353    * doesn't actually allocate it.
   354    */
   355   bool ParseLazyURIValue(const nsAString& aString);
   357   /**
   358    * Parse a margin string of format 'top, right, bottom, left' into
   359    * an nsIntMargin.
   360    *
   361    * @param aString the string to parse
   362    * @return whether the value could be parsed
   363    */
   364   bool ParseIntMarginValue(const nsAString& aString);
   366   /**
   367    * Convert a URL nsAttrValue to an Image nsAttrValue.
   368    *
   369    * @param aDocument the document this nsAttrValue belongs to.
   370    */
   371   void LoadImage(nsIDocument* aDocument);
   373   /**
   374    * Parse a string into a CSS style rule.
   375    *
   376    * @param aString the style attribute value to be parsed.
   377    * @param aElement the element the attribute is set on.
   378    */
   379   bool ParseStyleAttribute(const nsAString& aString,
   380                            nsStyledElementNotElementCSSInlineStyle* aElement);
   382   size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
   384 private:
   385   // These have to be the same as in ValueType
   386   enum ValueBaseType {
   387     eStringBase =    eString,    // 00
   388     eOtherBase =     0x01,       // 01
   389     eAtomBase =      eAtom,      // 10
   390     eIntegerBase =   0x03        // 11
   391   };
   393   inline ValueBaseType BaseType() const;
   394   inline bool IsSVGType(ValueType aType) const;
   396   /**
   397    * Get the index of an EnumTable in the sEnumTableArray.
   398    * If the EnumTable is not in the sEnumTableArray, it is added.
   399    *
   400    * @param aTable   the EnumTable to get the index of.
   401    * @return         the index of the EnumTable.
   402    */
   403   int16_t  GetEnumTableIndex(const EnumTable* aTable);
   405   inline void SetPtrValueAndType(void* aValue, ValueBaseType aType);
   406   void SetIntValueAndType(int32_t aValue, ValueType aType,
   407                           const nsAString* aStringValue);
   408   void SetColorValue(nscolor aColor, const nsAString& aString);
   409   void SetMiscAtomOrString(const nsAString* aValue);
   410   void ResetMiscAtomOrString();
   411   void SetSVGType(ValueType aType, const void* aValue,
   412                   const nsAString* aSerialized);
   413   inline void ResetIfSet();
   415   inline void* GetPtr() const;
   416   inline MiscContainer* GetMiscContainer() const;
   417   inline int32_t GetIntInternal() const;
   419   // Clears the current MiscContainer.  This will return null if there is no
   420   // existing container.
   421   MiscContainer* ClearMiscContainer();
   422   // Like ClearMiscContainer, except allocates a new container if one does not
   423   // exist already.
   424   MiscContainer* EnsureEmptyMiscContainer();
   425   bool EnsureEmptyAtomArray();
   426   already_AddRefed<nsStringBuffer>
   427     GetStringBuffer(const nsAString& aValue) const;
   428   // aStrict is set true if stringifying the return value equals with
   429   // aValue.
   430   int32_t StringToInteger(const nsAString& aValue,
   431                           bool* aStrict,
   432                           nsresult* aErrorCode,
   433                           bool aCanBePercent = false,
   434                           bool* aIsPercent = nullptr) const;
   435   // Given an enum table and a particular entry in that table, return
   436   // the actual integer value we should store.
   437   int32_t EnumTableEntryToValue(const EnumTable* aEnumTable,
   438                                 const EnumTable* aTableEntry);  
   440   static nsTArray<const EnumTable*>* sEnumTableArray;
   442   uintptr_t mBits;
   443 };
   445 inline const nsAttrValue&
   446 nsAttrValue::operator=(const nsAttrValue& aOther)
   447 {
   448   SetTo(aOther);
   449   return *this;
   450 }
   452 inline nsIAtom*
   453 nsAttrValue::GetAtomValue() const
   454 {
   455   NS_PRECONDITION(Type() == eAtom, "wrong type");
   456   return reinterpret_cast<nsIAtom*>(GetPtr());
   457 }
   459 inline nsAttrValue::ValueBaseType
   460 nsAttrValue::BaseType() const
   461 {
   462   return static_cast<ValueBaseType>(mBits & NS_ATTRVALUE_BASETYPE_MASK);
   463 }
   465 inline void*
   466 nsAttrValue::GetPtr() const
   467 {
   468   NS_ASSERTION(BaseType() != eIntegerBase,
   469                "getting pointer from non-pointer");
   470   return reinterpret_cast<void*>(mBits & NS_ATTRVALUE_POINTERVALUE_MASK);
   471 }
   473 inline bool
   474 nsAttrValue::IsEmptyString() const
   475 {
   476   return !mBits;
   477 }
   479 inline void
   480 nsAttrValue::ToString(mozilla::dom::DOMString& aResult) const
   481 {
   482   switch (Type()) {
   483     case eString:
   484     {
   485       nsStringBuffer* str = static_cast<nsStringBuffer*>(GetPtr());
   486       if (str) {
   487         aResult.SetStringBuffer(str, str->StorageSize()/sizeof(char16_t) - 1);
   488       }
   489       // else aResult is already empty
   490       return;
   491     }
   492     case eAtom:
   493     {
   494       nsIAtom *atom = static_cast<nsIAtom*>(GetPtr());
   495       aResult.SetStringBuffer(atom->GetStringBuffer(), atom->GetLength());
   496       break;
   497     }
   498     default:
   499     {
   500       ToString(aResult.AsAString());
   501     }
   502   }
   503 }
   505 #endif

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