/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
* A struct that represents the value (type and actual data) of an
* attribute.
*/
#ifndef nsAttrValue_h___
#define nsAttrValue_h___
#include <type_traits>
#include "nscore.h"
#include "nsString.h"
#include "mozilla/StringBuffer.h"
#include "nsColor.h"
#include "nsCaseTreatment.h"
#include "nsMargin.h"
#include "nsStringFwd.h"
#include "nsTArrayForwardDeclare.h"
#include "nsAtom.h"
#include "mozilla/AtomArray.h"
#include "mozilla/EnumTypeTraits.h"
#include "mozilla/MemoryReporting.h"
class nsIPrincipal;
class nsIURI;
class nsStyledElement;
struct MiscContainer;
namespace mozilla {
class DeclarationBlock;
class ShadowParts;
class SVGAnimatedIntegerPair;
class SVGAnimatedLength;
class SVGAnimatedNumberPair;
class SVGAnimatedOrient;
class SVGAnimatedPreserveAspectRatio;
class SVGAnimatedViewBox;
class SVGLengthList;
class SVGNumberList;
class SVGPathData;
class SVGPointList;
class SVGStringList;
class SVGTransformList;
struct AttrAtomArray {
AtomArray mArray;
mutable bool mMayContainDuplicates =
false;
UniquePtr<AttrAtomArray> CreateDeduplicatedCopyIfDifferent()
const {
if (!mMayContainDuplicates) {
return nullptr;
}
return CreateDeduplicatedCopyIfDifferentImpl();
}
bool operator==(
const AttrAtomArray& aOther)
const {
return mArray == aOther.mArray;
}
size_t ShallowSizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
const {
return aMallocSizeOf(
this) +
mArray.ShallowSizeOfExcludingThis(aMallocSizeOf);
}
private:
UniquePtr<AttrAtomArray> CreateDeduplicatedCopyIfDifferentImpl()
const;
};
namespace dom {
class DOMString;
}
}
// namespace mozilla
#define NS_ATTRVALUE_MAX_STRINGLENGTH_ATOM 12
const uintptr_t NS_ATTRVALUE_BASETYPE_MASK = 3;
#define NS_ATTRVALUE_POINTERVALUE_MASK (~NS_ATTRVALUE_BASETYPE_MASK)
#define NS_ATTRVALUE_INTEGERTYPE_BITS 4
#define NS_ATTRVALUE_INTEGERTYPE_MASK \
(uintptr_t((1 << NS_ATTRVALUE_INTEGERTYPE_BITS) - 1))
#define NS_ATTRVALUE_INTEGERTYPE_MULTIPLIER (1 << NS_ATTRVALUE_INTEGERTYPE_BITS)
#define NS_ATTRVALUE_INTEGERTYPE_MAXVALUE \
((1 << (31 - NS_ATTRVALUE_INTEGERTYPE_BITS)) - 1)
#define NS_ATTRVALUE_INTEGERTYPE_MINVALUE \
(-NS_ATTRVALUE_INTEGERTYPE_MAXVALUE - 1)
#define NS_ATTRVALUE_ENUMTABLEINDEX_BITS \
(32 - 16 - NS_ATTRVALUE_INTEGERTYPE_BITS)
#define NS_ATTRVALUE_ENUMTABLE_VALUE_NEEDS_TO_UPPER \
(1 << (NS_ATTRVALUE_ENUMTABLEINDEX_BITS - 1))
#define NS_ATTRVALUE_ENUMTABLEINDEX_MAXVALUE \
(NS_ATTRVALUE_ENUMTABLE_VALUE_NEEDS_TO_UPPER - 1)
#define NS_ATTRVALUE_ENUMTABLEINDEX_MASK \
(uintptr_t((((1 << NS_ATTRVALUE_ENUMTABLEINDEX_BITS) - 1) & \
~NS_ATTRVALUE_ENUMTABLE_VALUE_NEEDS_TO_UPPER)))
/**
* A class used to construct a nsString from a mozilla::StringBuffer (we might
* want to move this to nsString at some point).
*
* WARNING: Note that nsCheapString doesn't take an explicit length -- it
* assumes the string is maximally large, given the mozilla::StringBuffer's
* storage size. This means the given string buffer *must* be sized exactly
* correctly for the string it contains (including one byte for a null
* terminator). If it has any unused storage space, then that will result in
* bogus characters at the end of our nsCheapString.
*/
class nsCheapString :
public nsString {
public:
explicit nsCheapString(mozilla::StringBuffer* aBuf) {
if (aBuf) {
Assign(aBuf, aBuf->StorageSize() /
sizeof(char16_t) - 1);
}
}
};
class nsAttrValue {
friend struct MiscContainer;
public:
// This has to be the same as in ValueBaseType
enum ValueType {
eString = 0x00,
// 00
// 01 this value indicates a 'misc' struct
eAtom = 0x02,
// 10
eInteger = 0x03,
// 0011
eColor = 0x07,
// 0111
eEnum = 0x0B,
// 1011 This should eventually die
ePercent = 0x0F,
// 1111
// Values below here won't matter, they'll be always stored in the 'misc'
// struct.
eCSSDeclaration = 0x10,
eURL,
eImage,
eAtomArray,
eDoubleValue,
// eShadowParts is refcounted in the misc container, as we do copy attribute
// values quite a bit (for example to process style invalidation), and the
// underlying value could get expensive to copy.
eShadowParts,
eSVGIntegerPair,
eSVGTypesBegin = eSVGIntegerPair,
eSVGOrient,
eSVGLength,
eSVGLengthList,
eSVGNumberList,
eSVGNumberPair,
eSVGPathData,
eSVGPointList,
eSVGPreserveAspectRatio,
eSVGStringList,
eSVGTransformList,
eSVGViewBox,
eSVGTypesEnd = eSVGViewBox,
};
nsAttrValue();
nsAttrValue(
const nsAttrValue& aOther);
explicit nsAttrValue(
const nsAString& aValue);
explicit nsAttrValue(nsAtom* aValue);
nsAttrValue(already_AddRefed<mozilla::DeclarationBlock> aValue,
const nsAString* aSerialized);
~nsAttrValue();
inline const nsAttrValue&
operator=(
const nsAttrValue& aOther);
static void Init();
static void Shutdown();
inline ValueType Type()
const;
// Returns true when this value is self-contained and does not depend on
// the state of its associated element.
// Returns false when this value depends on the state of its associated
// element and may be invalid if that state has been changed by changes to
// that element state outside of attribute setting.
inline bool StoresOwnData()
const;
void Reset();
void SetTo(
const nsAttrValue& aOther);
void SetTo(
const nsAString& aValue);
void SetTo(nsAtom* aValue);
void SetTo(int16_t aInt);
void SetTo(int32_t aInt,
const nsAString* aSerialized);
void SetTo(
double aValue,
const nsAString* aSerialized);
void SetTo(already_AddRefed<mozilla::DeclarationBlock> aValue,
const nsAString* aSerialized);
void SetTo(nsIURI* aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGAnimatedIntegerPair& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGAnimatedLength& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGAnimatedNumberPair& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGAnimatedOrient& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGAnimatedPreserveAspectRatio& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGAnimatedViewBox& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGLengthList& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGNumberList& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGPathData& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGPointList& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGStringList& aValue,
const nsAString* aSerialized);
void SetTo(
const mozilla::SVGTransformList& aValue,
const nsAString* aSerialized);
/**
* Sets this object with the string or atom representation of aValue.
*
* After calling this method, this object will have type eString unless the
* type of aValue is eAtom, in which case this object will also have type
* eAtom.
*/
void SetToSerialized(
const nsAttrValue& aValue);
void SwapValueWith(nsAttrValue& aOther);
void RemoveDuplicatesFromAtomArray();
void ToString(nsAString& aResult)
const;
inline void ToString(mozilla::dom::DOMString& aResult)
const;
/**
* Returns the value of this object as an atom. If necessary, the value will
* first be serialised using ToString before converting to an atom.
*/
already_AddRefed<nsAtom> GetAsAtom()
const;
// Methods to get value. These methods do not convert so only use them
// to retrieve the datatype that this nsAttrValue has.
inline bool IsEmptyString()
const;
const nsCheapString GetStringValue()
const;
inline nsAtom* GetAtomValue()
const;
inline int32_t GetIntegerValue()
const;
bool GetColorValue(nscolor& aColor)
const;
inline int16_t GetEnumValue()
const;
inline double GetPercentValue()
const;
inline const mozilla::AttrAtomArray* GetAtomArrayValue()
const;
inline mozilla::DeclarationBlock* GetCSSDeclarationValue()
const;
inline nsIURI* GetURLValue()
const;
inline double GetDoubleValue()
const;
inline const mozilla::ShadowParts& GetShadowPartsValue()
const;
/**
* Returns the string corresponding to the stored enum value.
*
* @param aResult the string representing the enum tag
* @param aRealTag wheter we want to have the real tag or the saved one
*/
void GetEnumString(nsAString& aResult,
bool aRealTag)
const;
// Methods to get access to atoms we may have
// Returns the number of atoms we have; 0 if we have none. It's OK
// to call this without checking the type first; it handles that.
uint32_t GetAtomCount()
const;
// Returns the atom at aIndex (0-based). Do not call this with
// aIndex >= GetAtomCount().
nsAtom* AtomAt(int32_t aIndex)
const;
uint32_t HashValue()
const;
bool Equals(
const nsAttrValue& aOther)
const;
// aCaseSensitive == eIgnoreCase means ASCII case-insenstive matching
bool Equals(
const nsAString& aValue, nsCaseTreatment aCaseSensitive)
const;
bool Equals(
const nsAtom* aValue, nsCaseTreatment aCaseSensitive)
const;
bool HasPrefix(
const nsAString& aValue, nsCaseTreatment aCaseSensitive)
const;
bool HasSuffix(
const nsAString& aValue, nsCaseTreatment aCaseSensitive)
const;
bool HasSubstring(
const nsAString& aValue,
nsCaseTreatment aCaseSensitive)
const;
/**
* Compares this object with aOther according to their string representation.
*
* For example, when called on an object with type eInteger and value 4, and
* given aOther of type eString and value "4", EqualsAsStrings will return
* true (while Equals will return false).
*/
bool EqualsAsStrings(
const nsAttrValue& aOther)
const;
/**
* Returns true if this AttrValue is equal to the given atom, or is an
* array which contains the given atom.
*/
bool Contains(nsAtom* aValue, nsCaseTreatment aCaseSensitive)
const;
/**
* Returns true if this AttrValue is an atom equal to the given
* string, or is an array of atoms which contains the given string.
* This always does a case-sensitive comparison.
*/
bool Contains(
const nsAString& aValue)
const;
void ParseAtom(
const nsAString& aValue);
void ParseAtomArray(
const nsAString& aValue);
void ParseAtomArray(nsAtom* aValue);
void ParseStringOrAtom(
const nsAString& aValue);
/**
* Parses an exportparts attribute.
*
* https://drafts.csswg.org/css-shadow-parts/#parsing-mapping-list
*/
void ParsePartMapping(
const nsAString&);
/**
* Structure for a mapping from int (enum) values to strings. When you use
* it you generally create an array of them.
* Instantiate like this:
* EnumTable myTable[] = {
* { "string1", 1 },
* { "string2", 2 },
* { nullptr, 0 }
* }
*/
struct EnumTable {
// EnumTable can be initialized either with an int16_t value
// or a value of an enumeration type that can fit within an int16_t.
constexpr EnumTable(
const char* aTag, int16_t aValue)
: tag(aTag), value(aValue) {}
template <
typename T,
typename =
typename std::enable_if<std::is_enum<T>::value>::type>
constexpr EnumTable(
const char* aTag, T aValue)
: tag(aTag), value(
static_cast<int16_t>(aValue)) {
static_assert(mozilla::EnumTypeFitsWithin<T, int16_t>::value,
"aValue must be an enum that fits within int16_t");
// TODO: statically assert there are no duplicate values, otherwise
// `GetEnumString()` above will return wrong values.
}
/** The string the value maps to */
const char* tag;
/** The enum value that maps to this string */
int16_t value;
};
/**
* Parse into an enum value.
*
* @param aValue the string to find the value for
* @param aTable the enumeration to map with
* @param aCaseSensitive specify if the parsing has to be case sensitive
* @param aDefaultValue if non-null, this function will always return true.
* Failure to parse aValue as one of the values in aTable will just
* cause aDefaultValue->value to be stored as the enumeration value.
* @return whether the enum value was found or not
*/
bool ParseEnumValue(
const nsAString& aValue,
const EnumTable* aTable,
bool aCaseSensitive,
const EnumTable* aDefaultValue = nullptr);
/**
* Parse a string into a dimension value. This is similar to
* https://html.spec.whatwg.org/multipage/#rules-for-parsing-dimension-values
* but drops the fractional part of the value for now, until we figure out how
* to store that in our nsAttrValue.
*
* The resulting value (if the parse succeeds) is one of eInteger,
* eDoubleValue, or ePercent, depending on whether we found a fractional part
* and whether we found '%' at the end of the value.
*
* @param aInput the string to parse
* @return whether the value could be parsed
*/
bool ParseHTMLDimension(
const nsAString& aInput) {
return DoParseHTMLDimension(aInput,
false);
}
/**
* Parse a string into a nonzero dimension value. This implements
* https://html.spec.whatwg.org/multipage/#rules-for-parsing-non-zero-dimension-values
* subject to the same constraints as ParseHTMLDimension above.
*
* @param aInput the string to parse
* @return whether the value could be parsed
*/
bool ParseNonzeroHTMLDimension(
const nsAString& aInput) {
return DoParseHTMLDimension(aInput,
true);
}
/**
* Parse a string value into an integer.
*
* @param aString the string to parse
* @return whether the value could be parsed
*/
bool ParseIntValue(
const nsAString& aString) {
return ParseIntWithBounds(aString, INT32_MIN, INT32_MAX);
}
/**
* Parse a string value into an integer with minimum value and maximum value.
*
* @param aString the string to parse
* @param aMin the minimum value (if value is less it will be bumped up)
* @param aMax the maximum value (if value is greater it will be chopped down)
* @return whether the value could be parsed
*/
bool ParseIntWithBounds(
const nsAString& aString, int32_t aMin,
int32_t aMax = INT32_MAX);
/**
* Parse a string value into an integer with a fallback for invalid values.
* Also allows clamping to a maximum value to support col/colgroup.span (this
* is not per spec right now).
*
* @param aString the string to parse
* @param aDefault the default value
* @param aMax the maximum value (if value is greater it will be clamped)
*/
void ParseIntWithFallback(
const nsAString& aString, int32_t aDefault,
int32_t aMax = INT32_MAX);
/**
* Parse a string value into a non-negative integer.
* This method follows the rules for parsing non-negative integer from:
* http://dev.w3.org/html5/spec/infrastructure.html#rules-for-parsing-non-negative-integers
*
* @param aString the string to parse
* @return whether the value is valid
*/
bool ParseNonNegativeIntValue(
const nsAString& aString);
/**
* Parse a string value into a clamped non-negative integer.
* This method follows the rules for parsing non-negative integer from:
* https://html.spec.whatwg.org/multipage/infrastructure.html#clamped-to-the-range
*
* @param aString the string to parse
* @param aDefault value to return for negative or invalid values
* @param aMin minimum value
* @param aMax maximum value
*/
void ParseClampedNonNegativeInt(
const nsAString& aString, int32_t aDefault,
int32_t aMin, int32_t aMax);
/**
* Parse a string value into a positive integer.
* This method follows the rules for parsing non-negative integer from:
* http://dev.w3.org/html5/spec/infrastructure.html#rules-for-parsing-non-negative-integers
* In addition of these rules, the value has to be greater than zero.
*
* This is generally used for parsing content attributes which reflecting IDL
* attributes are limited to only non-negative numbers greater than zero, see:
* http://dev.w3.org/html5/spec/common-dom-interfaces.html#limited-to-only-non-negative-numbers-greater-than-zero
*
* @param aString the string to parse
* @return whether the value was valid
*/
bool ParsePositiveIntValue(
const nsAString& aString);
/**
* Parse a string into a color. This implements what HTML5 calls the
* "rules for parsing a legacy color value".
*
* @param aString the string to parse
* @return whether the value could be parsed
*/
bool ParseColor(
const nsAString& aString);
/**
* Parse a string value into a double-precision floating point value.
*
* @param aString the string to parse
* @return whether the value could be parsed
*/
bool ParseDoubleValue(
const nsAString& aString);
/**
* Parse a string into a CSS style rule.
*
* @param aString the style attribute value to be parsed.
* @param aElement the element the attribute is set on.
* @param aMaybeScriptedPrincipal if available, the scripted principal
* responsible for this attribute value, as passed to
* Element::ParseAttribute.
*/
bool ParseStyleAttribute(
const nsAString& aString,
nsIPrincipal* aMaybeScriptedPrincipal,
nsStyledElement* aElement);
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf)
const;
nsAtom* GetStoredAtom()
const;
mozilla::StringBuffer* GetStoredStringBuffer()
const;
private:
// These have to be the same as in ValueType
enum ValueBaseType {
eStringBase = eString,
// 00
eOtherBase = 0x01,
// 01
eAtomBase = eAtom,
// 10
eIntegerBase = 0x03
// 11
};
inline ValueBaseType BaseType()
const;
inline bool IsSVGType(ValueType aType)
const;
/**
* Get the index of an EnumTable in the sEnumTableArray.
* If the EnumTable is not in the sEnumTableArray, it is added.
*
* @param aTable the EnumTable to get the index of.
* @return the index of the EnumTable.
*/
int16_t GetEnumTableIndex(
const EnumTable* aTable);
inline void SetPtrValueAndType(
void* aValue, ValueBaseType aType);
void SetIntValueAndType(int32_t aValue, ValueType aType,
const nsAString* aStringValue);
// aType can be ePercent or eDoubleValue.
void SetDoubleValueAndType(
double aValue, ValueType aType,
const nsAString* aStringValue);
bool SetColorValue(nscolor aColor,
const nsAString& aString);
void SetMiscAtomOrString(
const nsAString* aValue);
void ResetMiscAtomOrString();
void SetSVGType(ValueType aType,
const void* aValue,
const nsAString* aSerialized);
inline void ResetIfSet();
inline void* GetPtr()
const;
inline MiscContainer* GetMiscContainer()
const;
inline int32_t GetIntInternal()
const;
// Clears the current MiscContainer. This will return null if there is no
// existing container.
MiscContainer* ClearMiscContainer();
// Like ClearMiscContainer, except allocates a new container if one does not
// exist already.
MiscContainer* EnsureEmptyMiscContainer();
already_AddRefed<mozilla::StringBuffer> GetStringBuffer(
const nsAString& aValue)
const;
// Given an enum table and a particular entry in that table, return
// the actual integer value we should store.
int32_t EnumTableEntryToValue(
const EnumTable* aEnumTable,
const EnumTable* aTableEntry);
template <
typename F>
bool SubstringCheck(
const nsAString& aValue,
nsCaseTreatment aCaseSensitive)
const;
static MiscContainer* AllocMiscContainer();
static void DeallocMiscContainer(MiscContainer* aCont);
static nsTArray<
const EnumTable*>* sEnumTableArray;
/**
* Helper for ParseHTMLDimension and ParseNonzeroHTMLDimension.
*
* @param aInput the string to parse
* @param aEnsureNonzero whether to fail the parse if the value is 0
* @return whether the value could be parsed
*/
bool DoParseHTMLDimension(
const nsAString& aInput,
bool aEnsureNonzero);
uintptr_t mBits;
};
inline const nsAttrValue& nsAttrValue::
operator=(
const nsAttrValue& aOther) {
SetTo(aOther);
return *
this;
}
inline nsAttrValue::ValueBaseType nsAttrValue::BaseType()
const {
return static_cast<ValueBaseType>(mBits & NS_ATTRVALUE_BASETYPE_MASK);
}
inline void* nsAttrValue::GetPtr()
const {
NS_ASSERTION(BaseType() != eIntegerBase,
"getting pointer from non-pointer");
return reinterpret_cast<
void*>(mBits & NS_ATTRVALUE_POINTERVALUE_MASK);
}
inline bool nsAttrValue::IsEmptyString()
const {
return !mBits; }
#endif
