pjs/content/base/src/nsAttrValue.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* IBM Corporation.
* Portions created by the Initial Developer are Copyright (C) 2003
* IBM Corporation. All Rights Reserved.
*
* Contributor(s):
* IBM Corporation
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* A struct that represents the value (type and actual data) of an
* attribute.
*/
#ifndef nsAttrValue_h___
#define nsAttrValue_h___
#include "nscore.h"
#include "nsString.h"
#include "nsStringBuffer.h"
#include "nsColor.h"
#include "nsCaseTreatment.h"
typedef unsigned long PtrBits;
class nsAString;
class nsIAtom;
class nsICSSStyleRule;
class nsISVGValue;
class nsIDocument;
template<class E> class nsCOMArray;
template<class E> class nsTPtrArray;
#define NS_ATTRVALUE_MAX_STRINGLENGTH_ATOM 12
#define NS_ATTRVALUE_BASETYPE_MASK (PtrBits(3))
#define NS_ATTRVALUE_POINTERVALUE_MASK (~NS_ATTRVALUE_BASETYPE_MASK)
#define NS_ATTRVALUE_INTEGERTYPE_BITS 5
#define NS_ATTRVALUE_INTEGERTYPE_MASK (PtrBits((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_ENUMTABLEINDEX_MAXVALUE ((1 << NS_ATTRVALUE_ENUMTABLEINDEX_BITS) - 1)
#define NS_ATTRVALUE_ENUMTABLEINDEX_MASK (PtrBits((1 << NS_ATTRVALUE_ENUMTABLEINDEX_BITS) - 1))
/**
* A class used to construct a nsString from a nsStringBuffer (we might
* want to move this to nsString at some point).
*/
class nsCheapString : public nsString {
public:
nsCheapString(nsStringBuffer* aBuf)
{
if (aBuf)
aBuf->ToString(aBuf->StorageSize()/2 - 1, *this);
}
};
class nsAttrValue {
public:
nsAttrValue();
nsAttrValue(const nsAttrValue& aOther);
explicit nsAttrValue(const nsAString& aValue);
explicit nsAttrValue(nsICSSStyleRule* aValue);
#ifdef MOZ_SVG
explicit nsAttrValue(nsISVGValue* aValue);
#endif
~nsAttrValue();
static nsresult Init();
static void Shutdown();
// This has to be the same as in ValueBaseType
enum ValueType {
eString = 0x00, // 00
// 01 this value indicates an 'misc' struct
eAtom = 0x02, // 10
eInteger = 0x03, // 00011
eColor = 0x07, // 00111
eProportional = 0x0B, // 01011
eEnum = 0x0F, // 01111 This should eventually die
ePercent = 0x13, // 10011
// Values below here won't matter, they'll be stored in the 'misc' struct
// anyway
eCSSStyleRule = 0x14,
eAtomArray = 0x15
#ifdef MOZ_SVG
,eSVGValue = 0x16
#endif
};
ValueType Type() const;
void Reset();
void SetTo(const nsAttrValue& aOther);
void SetTo(const nsAString& aValue);
void SetTo(PRInt16 aInt);
void SetTo(nsICSSStyleRule* aValue);
#ifdef MOZ_SVG
void SetTo(nsISVGValue* aValue);
#endif
void SwapValueWith(nsAttrValue& aOther);
void ToString(nsAString& aResult) const;
// Methods to get value. These methods do not convert so only use them
// to retrieve the datatype that this nsAttrValue has.
inline PRBool IsEmptyString() const;
const nsCheapString GetStringValue() const;
inline nsIAtom* GetAtomValue() const;
inline PRInt32 GetIntegerValue() const;
PRBool GetColorValue(nscolor& aColor) const;
inline PRInt32 GetProportionalValue() const;
inline PRInt16 GetEnumValue() const;
inline float GetPercentValue() const;
inline nsCOMArray<nsIAtom>* GetAtomArrayValue() const;
inline nsICSSStyleRule* GetCSSStyleRuleValue() const;
#ifdef MOZ_SVG
inline nsISVGValue* GetSVGValue() const;
#endif
// 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.
PRInt32 GetAtomCount() const;
// Returns the atom at aIndex (0-based). Do not call this with
// aIndex >= GetAtomCount().
nsIAtom* AtomAt(PRInt32 aIndex) const;
PRUint32 HashValue() const;
PRBool Equals(const nsAttrValue& aOther) const;
PRBool Equals(const nsAString& aValue, nsCaseTreatment aCaseSensitive) const;
PRBool Equals(nsIAtom* aValue, nsCaseTreatment aCaseSensitive) const;
/**
* Returns true if this AttrValue is equal to the given atom, or is an
* array which contains the given atom.
*/
PRBool Contains(nsIAtom* aValue, nsCaseTreatment aCaseSensitive) const;
void ParseAtom(const nsAString& aValue);
void ParseAtomArray(const nsAString& aValue);
void ParseStringOrAtom(const nsAString& aValue);
/**
* 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 },
* { 0 }
* }
*/
struct EnumTable {
/** The string the value maps to */
const char* tag;
/** The enum value that maps to this string */
PRInt16 value;
};
/**
* Parse into an enum value.
*
* @param aValue the string to find the value for
* @param aTable the enumeration to map with
* @param aResult the enum mapping [OUT]
* @return whether the enum value was found or not
*/
PRBool ParseEnumValue(const nsAString& aValue,
const EnumTable* aTable,
PRBool aCaseSensitive = PR_FALSE);
/**
* Parse a string into an integer. Can optionally parse percent (n%) and
* proportional (n*). This method explicitly sets a lower bound of zero on
* the element, whether it be proportional or percent or raw integer.
*
* @param aString the string to parse
* @param aCanBePercent PR_TRUE if it can be a percent value (%)
* @param aCanBeProportional PR_TRUE if it can be a proportional value (*)
* @return whether the value could be parsed
*/
PRBool ParseSpecialIntValue(const nsAString& aString,
PRBool aCanBePercent,
PRBool aCanBeProportional);
/**
* Parse a string value into an integer.
*
* @param aString the string to parse
* @return whether the value could be parsed
*/
PRBool ParseIntValue(const nsAString& aString) {
return ParseIntWithBounds(aString, NS_ATTRVALUE_INTEGERTYPE_MINVALUE,
NS_ATTRVALUE_INTEGERTYPE_MAXVALUE);
}
/**
* 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
*/
PRBool ParseIntWithBounds(const nsAString& aString, PRInt32 aMin,
PRInt32 aMax = NS_ATTRVALUE_INTEGERTYPE_MAXVALUE);
/**
* Parse a string into a color.
*
* @param aString the string to parse
* @param aDocument the document (to find out whether we're in quirks mode)
* @return whether the value could be parsed
*/
PRBool ParseColor(const nsAString& aString, nsIDocument* aDocument);
private:
// These have to be the same as in ValueType
enum ValueBaseType {
eStringBase = eString, // 00
eOtherBase = 0x01, // 01
eAtomBase = eAtom, // 10
eIntegerBase = 0x03 // 11
};
struct MiscContainer
{
ValueType mType;
union {
nscolor mColor;
nsICSSStyleRule* mCSSStyleRule;
nsCOMArray<nsIAtom>* mAtomArray;
#ifdef MOZ_SVG
nsISVGValue* mSVGValue;
#endif
};
};
inline ValueBaseType BaseType() const;
inline void SetPtrValueAndType(void* aValue, ValueBaseType aType);
inline void SetIntValueAndType(PRInt32 aValue, ValueType aType);
inline void ResetIfSet();
inline void* GetPtr() const;
inline MiscContainer* GetMiscContainer() const;
inline PRInt32 GetIntInternal() const;
PRBool EnsureEmptyMiscContainer();
PRBool EnsureEmptyAtomArray();
static nsTPtrArray<const EnumTable>* sEnumTableArray;
PtrBits mBits;
};
/**
* Implementation of inline methods
*/
inline nsIAtom*
nsAttrValue::GetAtomValue() const
{
NS_PRECONDITION(Type() == eAtom, "wrong type");
return reinterpret_cast<nsIAtom*>(GetPtr());
}
inline PRInt32
nsAttrValue::GetIntegerValue() const
{
NS_PRECONDITION(Type() == eInteger, "wrong type");
return GetIntInternal();
}
inline PRInt32
nsAttrValue::GetProportionalValue() const
{
NS_PRECONDITION(Type() == eProportional, "wrong type");
return GetIntInternal();
}
inline PRInt16
nsAttrValue::GetEnumValue() const
{
NS_PRECONDITION(Type() == eEnum, "wrong type");
// We don't need to worry about sign extension here since we're
// returning an PRInt16 which will cut away the top bits.
return static_cast<PRInt16>
(GetIntInternal() >> NS_ATTRVALUE_ENUMTABLEINDEX_BITS);
}
inline float
nsAttrValue::GetPercentValue() const
{
NS_PRECONDITION(Type() == ePercent, "wrong type");
return static_cast<float>(GetIntInternal()) /
100.0f;
}
inline nsCOMArray<nsIAtom>*
nsAttrValue::GetAtomArrayValue() const
{
NS_PRECONDITION(Type() == eAtomArray, "wrong type");
return GetMiscContainer()->mAtomArray;
}
inline nsICSSStyleRule*
nsAttrValue::GetCSSStyleRuleValue() const
{
NS_PRECONDITION(Type() == eCSSStyleRule, "wrong type");
return GetMiscContainer()->mCSSStyleRule;
}
#ifdef MOZ_SVG
inline nsISVGValue*
nsAttrValue::GetSVGValue() const
{
NS_PRECONDITION(Type() == eSVGValue, "wrong type");
return GetMiscContainer()->mSVGValue;
}
#endif
inline nsAttrValue::ValueBaseType
nsAttrValue::BaseType() const
{
return static_cast<ValueBaseType>(mBits & NS_ATTRVALUE_BASETYPE_MASK);
}
inline void
nsAttrValue::SetPtrValueAndType(void* aValue, ValueBaseType aType)
{
NS_ASSERTION(!(NS_PTR_TO_INT32(aValue) & ~NS_ATTRVALUE_POINTERVALUE_MASK),
"pointer not properly aligned, this will crash");
mBits = reinterpret_cast<PtrBits>(aValue) | aType;
}
inline void
nsAttrValue::SetIntValueAndType(PRInt32 aValue, ValueType aType)
{
#ifdef DEBUG
{
PRInt32 tmp = aValue * NS_ATTRVALUE_INTEGERTYPE_MULTIPLIER;
NS_ASSERTION(tmp / NS_ATTRVALUE_INTEGERTYPE_MULTIPLIER == aValue,
"Integer too big to fit");
}
#endif
mBits = (aValue * NS_ATTRVALUE_INTEGERTYPE_MULTIPLIER) | aType;
}
inline void
nsAttrValue::ResetIfSet()
{
if (mBits) {
Reset();
}
}
inline void*
nsAttrValue::GetPtr() const
{
NS_ASSERTION(BaseType() != eIntegerBase,
"getting pointer from non-pointer");
return reinterpret_cast<void*>(mBits & NS_ATTRVALUE_POINTERVALUE_MASK);
}
inline nsAttrValue::MiscContainer*
nsAttrValue::GetMiscContainer() const
{
NS_ASSERTION(BaseType() == eOtherBase, "wrong type");
return static_cast<MiscContainer*>(GetPtr());
}
inline PRInt32
nsAttrValue::GetIntInternal() const
{
NS_ASSERTION(BaseType() == eIntegerBase,
"getting integer from non-integer");
// Make sure we get a signed value.
// Lets hope the optimizer optimizes this into a shift. Unfortunatly signed
// bitshift right is implementaion dependant.
return static_cast<PRInt32>(mBits & ~NS_ATTRVALUE_INTEGERTYPE_MASK) /
NS_ATTRVALUE_INTEGERTYPE_MULTIPLIER;
}
inline PRBool
nsAttrValue::IsEmptyString() const
{
return !mBits;
}
#endif