gecko-dev/layout/style/nsCSSValue.h

520 строки
19 KiB
C++

/* -*- 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
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of 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 ***** */
/* representation of simple property values within CSS declarations */
#ifndef nsCSSValue_h___
#define nsCSSValue_h___
#include "nsColor.h"
#include "nsString.h"
#include "nsCoord.h"
#include "nsCSSProperty.h"
#include "nsIURI.h"
#include "nsCOMPtr.h"
#include "nsAutoPtr.h"
#include "nsCRTGlue.h"
#include "nsStringBuffer.h"
class imgIRequest;
class nsIDocument;
class nsIPrincipal;
// Deletes a linked list iteratively to avoid blowing up the stack (bug 456196).
#define NS_CSS_DELETE_LIST_MEMBER(type_, ptr_, member_) \
{ \
type_ *cur = (ptr_)->member_; \
(ptr_)->member_ = nsnull; \
while (cur) { \
type_ *next = cur->member_; \
cur->member_ = nsnull; \
delete cur; \
cur = next; \
} \
}
// Clones a linked list iteratively to avoid blowing up the stack.
// If it fails to clone the entire list then 'to_' is deleted and
// we return null.
#define NS_CSS_CLONE_LIST_MEMBER(type_, from_, member_, to_, args_) \
{ \
type_ *dest = (to_); \
(to_)->member_ = nsnull; \
for (const type_ *src = (from_)->member_; src; src = src->member_) { \
type_ *clone = src->Clone args_; \
if (!clone) { \
delete (to_); \
return nsnull; \
} \
dest->member_ = clone; \
dest = clone; \
} \
}
enum nsCSSUnit {
eCSSUnit_Null = 0, // (n/a) null unit, value is not specified
eCSSUnit_Auto = 1, // (n/a) value is algorithmic
eCSSUnit_Inherit = 2, // (n/a) value is inherited
eCSSUnit_Initial = 3, // (n/a) value is default UA value
eCSSUnit_None = 4, // (n/a) value is none
eCSSUnit_Normal = 5, // (n/a) value is normal (algorithmic, different than auto)
eCSSUnit_System_Font = 6, // (n/a) value is -moz-use-system-font
eCSSUnit_Dummy = 7, // (n/a) a fake but specified value, used
// only in temporary values
eCSSUnit_DummyInherit = 8, // (n/a) a fake but specified value, used
// only in temporary values
eCSSUnit_RectIsAuto = 9, // (n/a) 'auto' for an entire rect()
eCSSUnit_String = 10, // (PRUnichar*) a string value
eCSSUnit_Attr = 11, // (PRUnichar*) a attr(string) value
eCSSUnit_Local_Font = 12, // (PRUnichar*) a local font name
eCSSUnit_Font_Format = 13, // (PRUnichar*) a font format name
eCSSUnit_Array = 20, // (nsCSSValue::Array*) a list of values
eCSSUnit_Counter = 21, // (nsCSSValue::Array*) a counter(string,[string]) value
eCSSUnit_Counters = 22, // (nsCSSValue::Array*) a counters(string,string[,string]) value
eCSSUnit_Function = 23, // (nsCSSValue::Array*) a function with parameters. First elem of array is name,
// the rest of the values are arguments.
eCSSUnit_URL = 30, // (nsCSSValue::URL*) value
eCSSUnit_Image = 31, // (nsCSSValue::Image*) value
eCSSUnit_Integer = 50, // (int) simple value
eCSSUnit_Enumerated = 51, // (int) value has enumerated meaning
eCSSUnit_EnumColor = 80, // (int) enumerated color (kColorKTable)
eCSSUnit_Color = 81, // (nscolor) an RGBA value
eCSSUnit_Percent = 90, // (float) 1.0 == 100%) value is percentage of something
eCSSUnit_Number = 91, // (float) value is numeric (usually multiplier, different behavior that percent)
// Length units - fixed
// US English
eCSSUnit_Inch = 100, // (float) 0.0254 meters
eCSSUnit_Foot = 101, // (float) 12 inches
eCSSUnit_Mile = 102, // (float) 5280 feet
// Metric
eCSSUnit_Millimeter = 207, // (float) 1/1000 meter
eCSSUnit_Centimeter = 208, // (float) 1/100 meter
eCSSUnit_Meter = 210, // (float) Standard length
eCSSUnit_Kilometer = 213, // (float) 1000 meters
// US Typographic
eCSSUnit_Point = 300, // (float) 1/72 inch
eCSSUnit_Pica = 301, // (float) 12 points == 1/6 inch
// European Typographic
eCSSUnit_Didot = 400, // (float) 15 didots == 16 points
eCSSUnit_Cicero = 401, // (float) 12 didots
// Length units - relative
// Font relative measure
eCSSUnit_EM = 800, // (float) == current font size
eCSSUnit_XHeight = 801, // (float) distance from top of lower case x to baseline
eCSSUnit_Char = 802, // (float) number of characters, used for width with monospace font
eCSSUnit_RootEM = 803, // (float) == root element font size
// Screen relative measure
eCSSUnit_Pixel = 900, // (float) CSS pixel unit
// Angular units
eCSSUnit_Degree = 1000, // (float) 360 per circle
eCSSUnit_Grad = 1001, // (float) 400 per circle
eCSSUnit_Radian = 1002, // (float) 2*pi per circle
// Frequency units
eCSSUnit_Hertz = 2000, // (float) 1/seconds
eCSSUnit_Kilohertz = 2001, // (float) 1000 Hertz
// Time units
eCSSUnit_Seconds = 3000, // (float) Standard time
eCSSUnit_Milliseconds = 3001 // (float) 1/1000 second
};
class nsCSSValue {
public:
struct Array;
friend struct Array;
struct URL;
friend struct URL;
struct Image;
friend struct Image;
// for valueless units only (null, auto, inherit, none, normal)
explicit nsCSSValue(nsCSSUnit aUnit = eCSSUnit_Null)
: mUnit(aUnit)
{
NS_ASSERTION(aUnit <= eCSSUnit_RectIsAuto, "not a valueless unit");
}
nsCSSValue(PRInt32 aValue, nsCSSUnit aUnit) NS_HIDDEN;
nsCSSValue(float aValue, nsCSSUnit aUnit) NS_HIDDEN;
nsCSSValue(const nsString& aValue, nsCSSUnit aUnit) NS_HIDDEN;
explicit nsCSSValue(nscolor aValue) NS_HIDDEN;
nsCSSValue(Array* aArray, nsCSSUnit aUnit) NS_HIDDEN;
explicit nsCSSValue(URL* aValue) NS_HIDDEN;
explicit nsCSSValue(Image* aValue) NS_HIDDEN;
nsCSSValue(const nsCSSValue& aCopy) NS_HIDDEN;
~nsCSSValue() { Reset(); }
NS_HIDDEN_(nsCSSValue&) operator=(const nsCSSValue& aCopy);
NS_HIDDEN_(PRBool) operator==(const nsCSSValue& aOther) const;
PRBool operator!=(const nsCSSValue& aOther) const
{
return !(*this == aOther);
}
nsCSSUnit GetUnit() const { return mUnit; }
PRBool IsLengthUnit() const
{ return eCSSUnit_Inch <= mUnit && mUnit <= eCSSUnit_Pixel; }
PRBool IsFixedLengthUnit() const
{ return eCSSUnit_Inch <= mUnit && mUnit <= eCSSUnit_Cicero; }
PRBool IsRelativeLengthUnit() const
{ return eCSSUnit_EM <= mUnit && mUnit <= eCSSUnit_Pixel; }
PRBool IsAngularUnit() const
{ return eCSSUnit_Degree <= mUnit && mUnit <= eCSSUnit_Radian; }
PRBool IsFrequencyUnit() const
{ return eCSSUnit_Hertz <= mUnit && mUnit <= eCSSUnit_Kilohertz; }
PRBool IsTimeUnit() const
{ return eCSSUnit_Seconds <= mUnit && mUnit <= eCSSUnit_Milliseconds; }
PRBool UnitHasStringValue() const
{ return eCSSUnit_String <= mUnit && mUnit <= eCSSUnit_Font_Format; }
PRInt32 GetIntValue() const
{
NS_ASSERTION(mUnit == eCSSUnit_Integer || mUnit == eCSSUnit_Enumerated ||
mUnit == eCSSUnit_EnumColor,
"not an int value");
return mValue.mInt;
}
float GetPercentValue() const
{
NS_ASSERTION(mUnit == eCSSUnit_Percent, "not a percent value");
return mValue.mFloat;
}
float GetFloatValue() const
{
NS_ASSERTION(eCSSUnit_Number <= mUnit, "not a float value");
return mValue.mFloat;
}
nsAString& GetStringValue(nsAString& aBuffer) const
{
NS_ASSERTION(UnitHasStringValue(), "not a string value");
aBuffer.Truncate();
PRUint32 len = NS_strlen(GetBufferValue(mValue.mString));
mValue.mString->ToString(len, aBuffer);
return aBuffer;
}
const PRUnichar* GetStringBufferValue() const
{
NS_ASSERTION(UnitHasStringValue(), "not a string value");
return GetBufferValue(mValue.mString);
}
nscolor GetColorValue() const
{
NS_ASSERTION((mUnit == eCSSUnit_Color), "not a color value");
return mValue.mColor;
}
Array* GetArrayValue() const
{
NS_ASSERTION(eCSSUnit_Array <= mUnit && mUnit <= eCSSUnit_Function,
"not an array value");
return mValue.mArray;
}
nsIURI* GetURLValue() const
{
NS_ASSERTION(mUnit == eCSSUnit_URL || mUnit == eCSSUnit_Image,
"not a URL value");
return mUnit == eCSSUnit_URL ?
mValue.mURL->mURI : mValue.mImage->mURI;
}
URL* GetURLStructValue() const
{
// Not allowing this for Image values, because if the caller takes
// a ref to them they won't be able to delete them properly.
NS_ASSERTION(mUnit == eCSSUnit_URL, "not a URL value");
return mValue.mURL;
}
const PRUnichar* GetOriginalURLValue() const
{
NS_ASSERTION(mUnit == eCSSUnit_URL || mUnit == eCSSUnit_Image,
"not a URL value");
return GetBufferValue(mUnit == eCSSUnit_URL ?
mValue.mURL->mString :
mValue.mImage->mString);
}
// Not making this inline because that would force us to include
// imgIRequest.h, which leads to REQUIRES hell, since this header is included
// all over.
NS_HIDDEN_(imgIRequest*) GetImageValue() const;
NS_HIDDEN_(nscoord) GetLengthTwips() const;
NS_HIDDEN_(void) Reset() // sets to null
{
if (mUnit != eCSSUnit_Null)
DoReset();
}
private:
NS_HIDDEN_(void) DoReset();
public:
NS_HIDDEN_(void) SetIntValue(PRInt32 aValue, nsCSSUnit aUnit);
NS_HIDDEN_(void) SetPercentValue(float aValue);
NS_HIDDEN_(void) SetFloatValue(float aValue, nsCSSUnit aUnit);
NS_HIDDEN_(void) SetStringValue(const nsString& aValue, nsCSSUnit aUnit);
NS_HIDDEN_(void) SetColorValue(nscolor aValue);
NS_HIDDEN_(void) SetArrayValue(nsCSSValue::Array* aArray, nsCSSUnit aUnit);
NS_HIDDEN_(void) SetURLValue(nsCSSValue::URL* aURI);
NS_HIDDEN_(void) SetImageValue(nsCSSValue::Image* aImage);
NS_HIDDEN_(void) SetAutoValue();
NS_HIDDEN_(void) SetInheritValue();
NS_HIDDEN_(void) SetInitialValue();
NS_HIDDEN_(void) SetNoneValue();
NS_HIDDEN_(void) SetNormalValue();
NS_HIDDEN_(void) SetSystemFontValue();
NS_HIDDEN_(void) SetDummyValue();
NS_HIDDEN_(void) SetDummyInheritValue();
NS_HIDDEN_(void) SetRectIsAutoValue();
NS_HIDDEN_(void) StartImageLoad(nsIDocument* aDocument)
const; // Not really const, but pretending
// Returns an already addrefed buffer. Can return null on allocation
// failure.
static nsStringBuffer* BufferFromString(const nsString& aValue);
struct URL {
// Methods are not inline because using an nsIPrincipal means requiring
// caps, which leads to REQUIRES hell, since this header is included all
// over.
// aString must not be null.
// aOriginPrincipal must not be null.
URL(nsIURI* aURI, nsStringBuffer* aString, nsIURI* aReferrer,
nsIPrincipal* aOriginPrincipal) NS_HIDDEN;
~URL() NS_HIDDEN;
NS_HIDDEN_(PRBool) operator==(const URL& aOther) const;
// URIEquals only compares URIs and principals (unlike operator==, which
// also compares the original strings). URIEquals also assumes that the
// mURI member of both URL objects is non-null. Do NOT call this method
// unless you're sure this is the case.
NS_HIDDEN_(PRBool) URIEquals(const URL& aOther) const;
nsCOMPtr<nsIURI> mURI; // null == invalid URL
nsStringBuffer* mString; // Could use nsRefPtr, but it'd add useless
// null-checks; this is never null.
nsCOMPtr<nsIURI> mReferrer;
nsCOMPtr<nsIPrincipal> mOriginPrincipal;
void AddRef() {
if (mRefCnt == PR_UINT32_MAX) {
NS_WARNING("refcount overflow, leaking nsCSSValue::URL");
return;
}
++mRefCnt;
}
void Release() {
if (mRefCnt == PR_UINT32_MAX) {
NS_WARNING("refcount overflow, leaking nsCSSValue::URL");
return;
}
if (--mRefCnt == 0)
delete this;
}
protected:
nsrefcnt mRefCnt;
};
struct Image : public URL {
// Not making the constructor and destructor inline because that would
// force us to include imgIRequest.h, which leads to REQUIRES hell, since
// this header is included all over.
// aString must not be null.
Image(nsIURI* aURI, nsStringBuffer* aString, nsIURI* aReferrer,
nsIPrincipal* aOriginPrincipal, nsIDocument* aDocument) NS_HIDDEN;
~Image() NS_HIDDEN;
// Inherit operator== from nsCSSValue::URL
nsCOMPtr<imgIRequest> mRequest; // null == image load blocked or somehow failed
// Override Release so we delete correctly without a virtual destructor
void Release() {
if (mRefCnt == PR_UINT32_MAX) {
NS_WARNING("refcount overflow, leaking nsCSSValue::Image");
return;
}
if (--mRefCnt == 0)
delete this;
}
};
private:
static const PRUnichar* GetBufferValue(nsStringBuffer* aBuffer) {
return static_cast<PRUnichar*>(aBuffer->Data());
}
protected:
nsCSSUnit mUnit;
union {
PRInt32 mInt;
float mFloat;
// Note: the capacity of the buffer may exceed the length of the string.
// If we're of a string type, mString is not null.
nsStringBuffer* mString;
nscolor mColor;
Array* mArray;
URL* mURL;
Image* mImage;
} mValue;
};
struct nsCSSValue::Array {
// return |Array| with reference count of zero
static Array* Create(PRUint16 aItemCount) {
return new (aItemCount) Array(aItemCount);
}
nsCSSValue& operator[](PRUint16 aIndex) {
NS_ASSERTION(aIndex < mCount, "out of range");
return mArray[aIndex];
}
const nsCSSValue& operator[](PRUint16 aIndex) const {
NS_ASSERTION(aIndex < mCount, "out of range");
return mArray[aIndex];
}
nsCSSValue& Item(PRUint16 aIndex) { return (*this)[aIndex]; }
const nsCSSValue& Item(PRUint16 aIndex) const { return (*this)[aIndex]; }
PRUint16 Count() const { return mCount; }
PRBool operator==(const Array& aOther) const
{
if (mCount != aOther.mCount)
return PR_FALSE;
for (PRUint16 i = 0; i < mCount; ++i)
if ((*this)[i] != aOther[i])
return PR_FALSE;
return PR_TRUE;
}
void AddRef() {
if (mRefCnt == PR_UINT16_MAX) {
NS_WARNING("refcount overflow, leaking nsCSSValue::Array");
return;
}
++mRefCnt;
NS_LOG_ADDREF(this, mRefCnt, "nsCSSValue::Array", sizeof(*this));
}
void Release() {
if (mRefCnt == PR_UINT16_MAX) {
NS_WARNING("refcount overflow, leaking nsCSSValue::Array");
return;
}
--mRefCnt;
NS_LOG_RELEASE(this, mRefCnt, "nsCSSValue::Array");
if (mRefCnt == 0)
delete this;
}
private:
PRUint16 mRefCnt;
const PRUint16 mCount;
// This must be the last sub-object, since we extend this array to
// be of size mCount; it needs to be a sub-object so it gets proper
// alignment.
nsCSSValue mArray[1];
void* operator new(size_t aSelfSize, PRUint16 aItemCount) CPP_THROW_NEW {
NS_ABORT_IF_FALSE(aItemCount > 0, "cannot have a 0 item count");
return ::operator new(aSelfSize + sizeof(nsCSSValue) * (aItemCount - 1));
}
void operator delete(void* aPtr) { ::operator delete(aPtr); }
nsCSSValue* First() { return mArray; }
const nsCSSValue* First() const { return mArray; }
#define CSSVALUE_LIST_FOR_EXTRA_VALUES(var) \
for (nsCSSValue *var = First() + 1, *var##_end = First() + mCount; \
var != var##_end; ++var)
Array(PRUint16 aItemCount)
: mRefCnt(0)
, mCount(aItemCount)
{
MOZ_COUNT_CTOR(nsCSSValue::Array);
CSSVALUE_LIST_FOR_EXTRA_VALUES(val) {
new (val) nsCSSValue();
}
}
~Array()
{
MOZ_COUNT_DTOR(nsCSSValue::Array);
CSSVALUE_LIST_FOR_EXTRA_VALUES(val) {
val->~nsCSSValue();
}
}
#undef CSSVALUE_LIST_FOR_EXTRA_VALUES
private:
Array(const Array& aOther); // not to be implemented
};
#endif /* nsCSSValue_h___ */