pjs/layout/style/nsStyleContext.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Netscape 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/NPL/
 *
 * 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 Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation. All
 * Rights Reserved.
 *
 * Contributor(s): 
 *   Pierre Phaneuf <pp@ludusdesign.com>
 *   IBM Corporation 
 * 
 * This Original Code has been modified by IBM Corporation.
 * Modifications made by IBM described herein are
 * Copyright (c) International Business Machines
 * Corporation, 2000
 *
 * Modifications to Mozilla code or documentation
 * identified per MPL Section 3.3
 *
 * Date         Modified by     Description of modification
 * 03/20/2000   IBM Corp.       Bidi - ability to change the default direction of the browser
 *
 */
 
#include "nsIStyleContext.h"
#include "nsIMutableStyleContext.h"
#include "nsStyleConsts.h"
#include "nsString.h"
#include "nsUnitConversion.h"
#include "nsIPresContext.h"
#include "nsIStyleRule.h"
#include "nsISupportsArray.h"
#include "nsCRT.h"

#include "nsCOMPtr.h"
#include "nsIStyleSet.h"
#include "nsISizeOfHandler.h"
#include "nsIPresShell.h"
#include "nsLayoutAtoms.h"
#include "prenv.h"

#ifdef IBMBIDI
#include "nsIUBidiUtils.h"
#endif

#ifdef DEBUG
// #define NOISY_DEBUG
#endif

// --------------------------------------
// Macros for getting style data structs
// - if using external data, get from
//   the member style data instance
// - if internal, get the data member
#ifdef SHARE_STYLECONTEXTS
#define GETSCDATA(data) mStyleData->m##data
#else
#define GETSCDATA(data) m##data
#endif


#ifdef SHARE_STYLECONTEXTS
  // define COMPUTE_STYLEDATA_CRC to actually compute a valid CRC32
  //  - if not defined then the CRC will simply be 0 (see StyleContextData::ComputeCRC)
  //  - this is to avoid the cost of computing a CRC if it is not being used
  //    by the style set in caching the style contexts (not using the FAST_CACHE)
  //    which is the current situation since the CRC can change when GetMutableStyleData
  //    is used to poke values into the style context data.
#define COMPUTE_STYLEDATA_CRC
#endif //SHARE_STYLECONTEXTS

#ifdef COMPUTE_STYLEDATA_CRC
  // helpers for computing CRC32 on style data
static void gen_crc_table();
static PRUint32 AccumulateCRC(PRUint32 crc_accum, const char *data_blk_ptr, int data_blk_size);
static PRUint32 StyleSideCRC(PRUint32 crc,const nsStyleSides *aStyleSides);
static PRUint32 StyleCoordCRC(PRUint32 crc, const nsStyleCoord* aCoord);
static PRUint32 StyleMarginCRC(PRUint32 crc, const nsMargin *aMargin);
static PRUint32 StyleStringCRC(PRUint32 aCrc, const nsString *aString);
#define STYLEDATA_NO_CRC (0)
#define STYLEDATA_DEFAULT_CRC (0xcafebabe)
#endif // COMPUTE_STYLEDATA_CRC

inline PRBool IsFixedUnit(nsStyleUnit aUnit, PRBool aEnumOK)
{
  return PRBool((aUnit == eStyleUnit_Null) || 
                (aUnit == eStyleUnit_Coord) || 
                (aEnumOK && (aUnit == eStyleUnit_Enumerated)));
}

static PRBool IsFixedData(const nsStyleSides& aSides, PRBool aEnumOK);
static nscoord CalcCoord(const nsStyleCoord& aCoord, 
                         const nscoord* aEnumTable, 
                         PRInt32 aNumEnums);

// EnsureBlockDisplay:
//  - if the display value (argument) is not a block-type
//    then we set it to a valid block display value
//  - For enforcing the floated/positioned element CSS2 rules
static void EnsureBlockDisplay(/*in out*/PRUint8 &display);

// --------------------
// nsStyleFont
//
nsStyleFont::nsStyleFont(const nsFont& aVariableFont, const nsFont& aFixedFont)
  : mFont(aVariableFont),
    mFixedFont(aFixedFont)
{ }

struct StyleFontImpl : public nsStyleFont {
  StyleFontImpl(const nsFont& aVariableFont, const nsFont& aFixedFont)
    : nsStyleFont(aVariableFont, aFixedFont)
  {}

  void ResetFrom(const nsStyleFont* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleFont& aSource);
  void CopyTo(nsStyleFont& aDest) const;
  PRInt32 CalcDifference(const StyleFontImpl& aOther) const;
  static PRInt32 CalcFontDifference(const nsFont& aFont1, const nsFont& aFont2);
  PRUint32 ComputeCRC32(PRUint32 crc) const;

private:  // These are not allowed
  StyleFontImpl(const StyleFontImpl& aOther);
  StyleFontImpl& operator=(const StyleFontImpl& aOther);
};

void StyleFontImpl::ResetFrom(const nsStyleFont* aParent, nsIPresContext* aPresContext)
{
  if (nsnull != aParent) {
    mFont = aParent->mFont;
    mFixedFont = aParent->mFixedFont;
    mFlags = aParent->mFlags;
  }
  else {
    aPresContext->GetDefaultFont(mFont);
    aPresContext->GetDefaultFixedFont(mFixedFont);
    mFlags = NS_STYLE_FONT_DEFAULT;
  }
}

void StyleFontImpl::SetFrom(const nsStyleFont& aSource)
{
  mFont = aSource.mFont;
  mFixedFont = aSource.mFixedFont;
  mFlags = aSource.mFlags;
}

void StyleFontImpl::CopyTo(nsStyleFont& aDest) const
{
  aDest.mFont = mFont;
  aDest.mFixedFont = mFixedFont;
  aDest.mFlags = mFlags;
}

PRInt32 StyleFontImpl::CalcDifference(const StyleFontImpl& aOther) const
{
  if (mFlags == aOther.mFlags) {
    PRInt32 impact = CalcFontDifference(mFont, aOther.mFont);
    if (impact < NS_STYLE_HINT_REFLOW) {
      impact = CalcFontDifference(mFixedFont, aOther.mFixedFont);
    }
    return impact;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRInt32 StyleFontImpl::CalcFontDifference(const nsFont& aFont1, const nsFont& aFont2)
{
  if ((aFont1.size == aFont2.size) && 
      (aFont1.style == aFont2.style) &&
      (aFont1.variant == aFont2.variant) &&
      (aFont1.weight == aFont2.weight) &&
      (aFont1.name == aFont2.name)) {
    if ((aFont1.decorations == aFont2.decorations)) {
      return NS_STYLE_HINT_NONE;
    }
    return NS_STYLE_HINT_VISUAL;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleFontImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;

#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&(mFont.size),sizeof(mFont.size));
  crc = AccumulateCRC(crc,(const char *)&(mFont.style),sizeof(mFont.style));
  crc = AccumulateCRC(crc,(const char *)&(mFont.variant),sizeof(mFont.variant));
  crc = AccumulateCRC(crc,(const char *)&(mFont.weight),sizeof(mFont.weight));
  crc = AccumulateCRC(crc,(const char *)&(mFont.decorations),sizeof(mFont.decorations));
  crc = StyleStringCRC(crc,&(mFont.name));
  crc = AccumulateCRC(crc,(const char *)&(mFixedFont.size),sizeof(mFixedFont.size));
  crc = AccumulateCRC(crc,(const char *)&(mFixedFont.style),sizeof(mFixedFont.style));
  crc = AccumulateCRC(crc,(const char *)&(mFixedFont.variant),sizeof(mFixedFont.variant));
  crc = AccumulateCRC(crc,(const char *)&(mFixedFont.weight),sizeof(mFixedFont.weight));
  crc = AccumulateCRC(crc,(const char *)&(mFixedFont.decorations),sizeof(mFixedFont.decorations));
  crc = StyleStringCRC(crc,&(mFixedFont.name));
  crc = AccumulateCRC(crc,(const char *)&mFlags,sizeof(mFlags));
#endif

  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

// --------------------
// nsStyleColor
//

struct StyleColorImpl: public nsStyleColor {
  StyleColorImpl(void)  { }

  void ResetFrom(const nsStyleColor* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleColor& aSource);
  void CopyTo(nsStyleColor& aDest) const;
  PRInt32 CalcDifference(const StyleColorImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleColorImpl(const StyleColorImpl& aOther);
  StyleColorImpl& operator=(const StyleColorImpl& aOther);
};

void StyleColorImpl::ResetFrom(const nsStyleColor* aParent, nsIPresContext* aPresContext)
{
  if (nsnull != aParent) {
    mColor = aParent->mColor;
    mOpacity = aParent->mOpacity;
    mCursor = aParent->mCursor; // fix for bugzilla bug 51113
  }
  else {
    if (nsnull != aPresContext) {
      aPresContext->GetDefaultColor(&mColor);
    }
    else {
      mColor = NS_RGB(0x00, 0x00, 0x00);
    }
    mOpacity = 1.0f;
    mCursor = NS_STYLE_CURSOR_AUTO; // fix for bugzilla bug 51113
  }

  mBackgroundFlags = NS_STYLE_BG_COLOR_TRANSPARENT | NS_STYLE_BG_IMAGE_NONE;
  if (nsnull != aPresContext) {
    aPresContext->GetDefaultBackgroundColor(&mBackgroundColor);
    aPresContext->GetDefaultBackgroundImageAttachment(&mBackgroundAttachment);
    aPresContext->GetDefaultBackgroundImageRepeat(&mBackgroundRepeat);
    aPresContext->GetDefaultBackgroundImageOffset(&mBackgroundXPosition, &mBackgroundYPosition);
    aPresContext->GetDefaultBackgroundImage(mBackgroundImage);
  }
  else {
    mBackgroundColor = NS_RGB(192,192,192);
    mBackgroundAttachment = NS_STYLE_BG_ATTACHMENT_SCROLL;
    mBackgroundRepeat = NS_STYLE_BG_REPEAT_XY;
    mBackgroundXPosition = 0;
    mBackgroundYPosition = 0;
  }
}

void StyleColorImpl::SetFrom(const nsStyleColor& aSource)
{
  mColor = aSource.mColor;
 
  mBackgroundAttachment = aSource.mBackgroundAttachment;
  mBackgroundFlags = aSource.mBackgroundFlags;
  mBackgroundRepeat = aSource.mBackgroundRepeat;

  mBackgroundColor = aSource.mBackgroundColor;
  mBackgroundXPosition = aSource.mBackgroundXPosition;
  mBackgroundYPosition = aSource.mBackgroundYPosition;
  mBackgroundImage = aSource.mBackgroundImage;

  mCursor = aSource.mCursor;
  mCursorImage = aSource.mCursorImage;
  mOpacity = aSource.mOpacity;
}

void StyleColorImpl::CopyTo(nsStyleColor& aDest) const
{
  aDest.mColor = mColor;
 
  aDest.mBackgroundAttachment = mBackgroundAttachment;
  aDest.mBackgroundFlags = mBackgroundFlags;
  aDest.mBackgroundRepeat = mBackgroundRepeat;

  aDest.mBackgroundColor = mBackgroundColor;
  aDest.mBackgroundXPosition = mBackgroundXPosition;
  aDest.mBackgroundYPosition = mBackgroundYPosition;
  aDest.mBackgroundImage = mBackgroundImage;

  aDest.mCursor = mCursor;
  aDest.mCursorImage = mCursorImage;
  aDest.mOpacity = mOpacity;
}

PRInt32 StyleColorImpl::CalcDifference(const StyleColorImpl& aOther) const
{
  if ((mColor == aOther.mColor) && 
      (mBackgroundAttachment == aOther.mBackgroundAttachment) &&
      (mBackgroundFlags == aOther.mBackgroundFlags) &&
      (mBackgroundRepeat == aOther.mBackgroundRepeat) &&
      (mBackgroundColor == aOther.mBackgroundColor) &&
      (mBackgroundXPosition == aOther.mBackgroundXPosition) &&
      (mBackgroundYPosition == aOther.mBackgroundYPosition) &&
      (mBackgroundImage == aOther.mBackgroundImage) &&
      (mCursor == aOther.mCursor) &&
      (mCursorImage == aOther.mCursorImage) &&
      (mOpacity == aOther.mOpacity)) {
    return NS_STYLE_HINT_NONE;
  }
  return NS_STYLE_HINT_VISUAL;
}

PRUint32 StyleColorImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mColor,sizeof(mColor));
  crc = AccumulateCRC(crc,(const char *)&mBackgroundAttachment,sizeof(mBackgroundAttachment));
  crc = AccumulateCRC(crc,(const char *)&mBackgroundFlags,sizeof(mBackgroundFlags));
  crc = AccumulateCRC(crc,(const char *)&mBackgroundRepeat,sizeof(mBackgroundRepeat));
  crc = AccumulateCRC(crc,(const char *)&mBackgroundColor,sizeof(mBackgroundColor));
  crc = AccumulateCRC(crc,(const char *)&mBackgroundXPosition,sizeof(mBackgroundXPosition));
  crc = AccumulateCRC(crc,(const char *)&mBackgroundYPosition,sizeof(mBackgroundYPosition));
  crc = StyleStringCRC(crc,&mBackgroundImage);
  crc = AccumulateCRC(crc,(const char *)&mCursor,sizeof(mCursor));
  crc = StyleStringCRC(crc,&mCursorImage);
  crc = AccumulateCRC(crc,(const char *)&mOpacity,sizeof(mOpacity));
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

static PRBool IsFixedData(const nsStyleSides& aSides, PRBool aEnumOK)
{
  return PRBool(IsFixedUnit(aSides.GetLeftUnit(), aEnumOK) &&
                IsFixedUnit(aSides.GetTopUnit(), aEnumOK) &&
                IsFixedUnit(aSides.GetRightUnit(), aEnumOK) &&
                IsFixedUnit(aSides.GetBottomUnit(), aEnumOK));
}

static nscoord CalcCoord(const nsStyleCoord& aCoord, 
                         const nscoord* aEnumTable, 
                         PRInt32 aNumEnums)
{
  switch (aCoord.GetUnit()) {
    case eStyleUnit_Null:
      return 0;
    case eStyleUnit_Coord:
      return aCoord.GetCoordValue();
    case eStyleUnit_Enumerated:
      if (nsnull != aEnumTable) {
        PRInt32 value = aCoord.GetIntValue();
        if ((0 <= value) && (value < aNumEnums)) {
          return aEnumTable[aCoord.GetIntValue()];
        }
      }
      break;
    default:
      NS_ERROR("bad unit type");
      break;
  }
  return 0;
}


#ifdef XP_MAC
#pragma mark -
#endif

struct StyleMarginImpl: public nsStyleMargin {
  StyleMarginImpl(void)
    : nsStyleMargin()
  {}

  void ResetFrom(const nsStyleMargin* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleMargin& aSource);
  void CopyTo(nsStyleMargin& aDest) const;
  void RecalcData(void);
  PRInt32 CalcDifference(const StyleMarginImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleMarginImpl(const StyleMarginImpl& aOther);
  StyleMarginImpl& operator=(const StyleMarginImpl& aOther);
};

void StyleMarginImpl::ResetFrom(const nsStyleMargin* aParent, nsIPresContext* aPresContext)
{
  // spacing values not inherited
  mMargin.Reset();
  mHasCachedMargin = PR_FALSE;
}

void StyleMarginImpl::SetFrom(const nsStyleMargin& aSource)
{
  nsCRT::memcpy((nsStyleMargin*)this, &aSource, sizeof(nsStyleMargin));
}

void StyleMarginImpl::CopyTo(nsStyleMargin& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStyleMargin*)this, sizeof(nsStyleMargin));
}

void StyleMarginImpl::RecalcData(void)
{
  if (IsFixedData(mMargin, PR_FALSE)) {
    nsStyleCoord  coord;
    mCachedMargin.left = CalcCoord(mMargin.GetLeft(coord), nsnull, 0);
    mCachedMargin.top = CalcCoord(mMargin.GetTop(coord), nsnull, 0);
    mCachedMargin.right = CalcCoord(mMargin.GetRight(coord), nsnull, 0);
    mCachedMargin.bottom = CalcCoord(mMargin.GetBottom(coord), nsnull, 0);

    mHasCachedMargin = PR_TRUE;
  }
  else {
    mHasCachedMargin = PR_FALSE;
  }
}

PRInt32 StyleMarginImpl::CalcDifference(const StyleMarginImpl& aOther) const
{
  if (mMargin == aOther.mMargin) {
    return NS_STYLE_HINT_NONE;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleMarginImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
  
#ifdef COMPUTE_STYLEDATA_CRC
  crc = StyleSideCRC(crc,&mMargin);
  crc = AccumulateCRC(crc,(const char *)&mHasCachedMargin,sizeof(mHasCachedMargin));
  crc = StyleMarginCRC(crc,&mCachedMargin);
#endif
  return crc;
}


#ifdef XP_MAC
#pragma mark -
#endif

struct StylePaddingImpl: public nsStylePadding {
  StylePaddingImpl(void)
    : nsStylePadding()
  {}

  void ResetFrom(const nsStylePadding* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStylePadding& aSource);
  void CopyTo(nsStylePadding& aDest) const;
  void RecalcData(void);
  PRInt32 CalcDifference(const StylePaddingImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StylePaddingImpl(const StylePaddingImpl& aOther);
  StylePaddingImpl& operator=(const StylePaddingImpl& aOther);
};

void StylePaddingImpl::ResetFrom(const nsStylePadding* aParent, nsIPresContext* aPresContext)
{
  // spacing values not inherited
  mPadding.Reset();
  mHasCachedPadding = PR_FALSE;
}

void StylePaddingImpl::SetFrom(const nsStylePadding& aSource)
{
  nsCRT::memcpy((nsStylePadding*)this, &aSource, sizeof(nsStylePadding));
}

void StylePaddingImpl::CopyTo(nsStylePadding& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStylePadding*)this, sizeof(nsStylePadding));
}

void StylePaddingImpl::RecalcData(void)
{
  if (IsFixedData(mPadding, PR_FALSE)) {
    nsStyleCoord  coord;
    mCachedPadding.left = CalcCoord(mPadding.GetLeft(coord), nsnull, 0);
    mCachedPadding.top = CalcCoord(mPadding.GetTop(coord), nsnull, 0);
    mCachedPadding.right = CalcCoord(mPadding.GetRight(coord), nsnull, 0);
    mCachedPadding.bottom = CalcCoord(mPadding.GetBottom(coord), nsnull, 0);

    mHasCachedPadding = PR_TRUE;
  }
  else {
    mHasCachedPadding = PR_FALSE;
  }
}

PRInt32 StylePaddingImpl::CalcDifference(const StylePaddingImpl& aOther) const
{
  if (mPadding == aOther.mPadding) {
    return NS_STYLE_HINT_NONE;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StylePaddingImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
  
#ifdef COMPUTE_STYLEDATA_CRC
  crc = StyleSideCRC(crc,&mPadding);
  crc = AccumulateCRC(crc,(const char *)&mHasCachedPadding,sizeof(mHasCachedPadding));
  crc = StyleMarginCRC(crc,&mCachedPadding);
#endif
  return crc;
}


#ifdef XP_MAC
#pragma mark -
#endif

struct StyleBorderImpl: public nsStyleBorder {
  StyleBorderImpl(void)
    : nsStyleBorder(), mWidthsInitialized(PR_FALSE)
  {}

  void ResetFrom(const nsStyleBorder* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleBorder& aSource);
  void CopyTo(nsStyleBorder& aDest) const;
  PRBool IsBorderSideVisible(PRUint8 aSide) const;
  void RecalcData(nscolor color);
  PRInt32 CalcDifference(const StyleBorderImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleBorderImpl(const StyleBorderImpl& aOther);
  StyleBorderImpl& operator=(const StyleBorderImpl& aOther);

  // XXX remove with deprecated methods
  PRBool        mWidthsInitialized;
};

void StyleBorderImpl::ResetFrom(const nsStyleBorder* aParent, nsIPresContext* aPresContext)
{
  // XXX support mBorderWidhts until deprecated methods are removed
  if (! mWidthsInitialized) {
    float pixelsToTwips = 20.0f;
    if (aPresContext) {
      aPresContext->GetPixelsToTwips(&pixelsToTwips);
    }
    mBorderWidths[NS_STYLE_BORDER_WIDTH_THIN] = NSIntPixelsToTwips(1, pixelsToTwips);
    mBorderWidths[NS_STYLE_BORDER_WIDTH_MEDIUM] = NSIntPixelsToTwips(3, pixelsToTwips);
    mBorderWidths[NS_STYLE_BORDER_WIDTH_THICK] = NSIntPixelsToTwips(5, pixelsToTwips);
    mWidthsInitialized = PR_TRUE;
  }

  // spacing values not inherited
  nsStyleCoord  medium(NS_STYLE_BORDER_WIDTH_MEDIUM, eStyleUnit_Enumerated);
  mBorder.SetLeft(medium);
  mBorder.SetTop(medium);
  mBorder.SetRight(medium);
  mBorder.SetBottom(medium);
  
  mBorderStyle[0] = NS_STYLE_BORDER_STYLE_NONE;  
  mBorderStyle[1] = NS_STYLE_BORDER_STYLE_NONE; 
  mBorderStyle[2] = NS_STYLE_BORDER_STYLE_NONE; 
  mBorderStyle[3] = NS_STYLE_BORDER_STYLE_NONE;  

  
  mBorderColor[0] = NS_RGB(0, 0, 0);  
  mBorderColor[1] = NS_RGB(0, 0, 0);  
  mBorderColor[2] = NS_RGB(0, 0, 0);  
  mBorderColor[3] = NS_RGB(0, 0, 0); 

  mBorderRadius.Reset();

  mFloatEdge = NS_STYLE_FLOAT_EDGE_CONTENT;
  
  mHasCachedBorder = PR_FALSE;
}

void StyleBorderImpl::SetFrom(const nsStyleBorder& aSource)
{
  nsCRT::memcpy((nsStyleBorder*)this, &aSource, sizeof(nsStyleBorder));
}

void StyleBorderImpl::CopyTo(nsStyleBorder& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStyleBorder*)this, sizeof(nsStyleBorder));
}

PRBool StyleBorderImpl::IsBorderSideVisible(PRUint8 aSide) const
{
	PRUint8 borderStyle = GetBorderStyle(aSide);
	return ((borderStyle != NS_STYLE_BORDER_STYLE_NONE)
       && (borderStyle != NS_STYLE_BORDER_STYLE_HIDDEN));
}

void StyleBorderImpl::RecalcData(nscolor aColor)
{
  if (((!IsBorderSideVisible(NS_SIDE_LEFT))|| 
       IsFixedUnit(mBorder.GetLeftUnit(), PR_TRUE)) &&
      ((!IsBorderSideVisible(NS_SIDE_TOP)) || 
       IsFixedUnit(mBorder.GetTopUnit(), PR_TRUE)) &&
      ((!IsBorderSideVisible(NS_SIDE_RIGHT)) || 
       IsFixedUnit(mBorder.GetRightUnit(), PR_TRUE)) &&
      ((!IsBorderSideVisible(NS_SIDE_BOTTOM)) || 
       IsFixedUnit(mBorder.GetBottomUnit(), PR_TRUE))) {
    nsStyleCoord  coord;
    if (!IsBorderSideVisible(NS_SIDE_LEFT)) {
      mCachedBorder.left = 0;
    }
    else {
      mCachedBorder.left = CalcCoord(mBorder.GetLeft(coord), mBorderWidths, 3);
    }
    if (!IsBorderSideVisible(NS_SIDE_TOP)) {
      mCachedBorder.top = 0;
    }
    else {
      mCachedBorder.top = CalcCoord(mBorder.GetTop(coord), mBorderWidths, 3);
    }
    if (!IsBorderSideVisible(NS_SIDE_RIGHT)) {
      mCachedBorder.right = 0;
    }
    else {
      mCachedBorder.right = CalcCoord(mBorder.GetRight(coord), mBorderWidths, 3);
    }
    if (!IsBorderSideVisible(NS_SIDE_BOTTOM)) {
      mCachedBorder.bottom = 0;
    }
    else {
      mCachedBorder.bottom = CalcCoord(mBorder.GetBottom(coord), mBorderWidths, 3);
    }
    mHasCachedBorder = PR_TRUE;
  }
  else {
    mHasCachedBorder = PR_FALSE;
  }

  if ((mBorderStyle[NS_SIDE_TOP] & BORDER_COLOR_DEFINED) == 0) {
    mBorderColor[NS_SIDE_TOP] = aColor;
  }
  if ((mBorderStyle[NS_SIDE_BOTTOM] & BORDER_COLOR_DEFINED) == 0) {
    mBorderColor[NS_SIDE_BOTTOM] = aColor;
  }
  if ((mBorderStyle[NS_SIDE_LEFT]& BORDER_COLOR_DEFINED) == 0) {
    mBorderColor[NS_SIDE_LEFT] = aColor;
  }
  if ((mBorderStyle[NS_SIDE_RIGHT] & BORDER_COLOR_DEFINED) == 0) {
    mBorderColor[NS_SIDE_RIGHT] = aColor;
  }
}

PRInt32 StyleBorderImpl::CalcDifference(const StyleBorderImpl& aOther) const
{
  if ((mBorder == aOther.mBorder) && 
      (mFloatEdge == aOther.mFloatEdge)) {
    PRInt32 ix;
    for (ix = 0; ix < 4; ix++) {
      if ((mBorderStyle[ix] != aOther.mBorderStyle[ix]) || 
          (mBorderColor[ix] != aOther.mBorderColor[ix])) {
        if ((mBorderStyle[ix] != aOther.mBorderStyle[ix]) &&
            ((NS_STYLE_BORDER_STYLE_NONE == mBorderStyle[ix]) ||
             (NS_STYLE_BORDER_STYLE_NONE == aOther.mBorderStyle[ix]) ||
             (NS_STYLE_BORDER_STYLE_HIDDEN == mBorderStyle[ix]) ||          // bug 45754
             (NS_STYLE_BORDER_STYLE_HIDDEN == aOther.mBorderStyle[ix]))) {
          return NS_STYLE_HINT_REFLOW;  // border on or off
        }
        return NS_STYLE_HINT_VISUAL;
      }
    }
    if (mBorderRadius != aOther.mBorderRadius) {
      return NS_STYLE_HINT_VISUAL;
    }
    return NS_STYLE_HINT_NONE;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleBorderImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
  
#ifdef COMPUTE_STYLEDATA_CRC
  crc = StyleSideCRC(crc,&mBorder);
  crc = StyleSideCRC(crc,&mBorderRadius);
  crc = AccumulateCRC(crc,(const char *)&mFloatEdge,sizeof(mFloatEdge));
  crc = AccumulateCRC(crc,(const char *)&mHasCachedBorder,sizeof(mHasCachedBorder));
  crc = StyleMarginCRC(crc,&mCachedBorder);
  crc = AccumulateCRC(crc,(const char *)mBorderStyle,sizeof(mBorderStyle)); // array of 4 elements
  crc = AccumulateCRC(crc,(const char *)mBorderColor,sizeof(mBorderColor)); // array ...
#endif
  return crc;
}


#ifdef XP_MAC
#pragma mark -
#endif

struct StyleOutlineImpl: public nsStyleOutline {
  StyleOutlineImpl(void)
    : nsStyleOutline(), mWidthsInitialized(PR_FALSE)
  {}

  void ResetFrom(const nsStyleOutline* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleOutline& aSource);
  void CopyTo(nsStyleOutline& aDest) const;
  void RecalcData(void);
  PRInt32 CalcDifference(const StyleOutlineImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleOutlineImpl(const StyleOutlineImpl& aOther);
  StyleOutlineImpl& operator=(const StyleOutlineImpl& aOther);

  // XXX remove with deprecated methods
  PRBool        mWidthsInitialized;
};

void StyleOutlineImpl::ResetFrom(const nsStyleOutline* aParent, nsIPresContext* aPresContext)
{
  // XXX support mBorderWidhts until deprecated methods are removed
  if (! mWidthsInitialized) {
    float pixelsToTwips = 20.0f;
    if (aPresContext) {
      aPresContext->GetPixelsToTwips(&pixelsToTwips);
    }
    mBorderWidths[NS_STYLE_BORDER_WIDTH_THIN] = NSIntPixelsToTwips(1, pixelsToTwips);
    mBorderWidths[NS_STYLE_BORDER_WIDTH_MEDIUM] = NSIntPixelsToTwips(3, pixelsToTwips);
    mBorderWidths[NS_STYLE_BORDER_WIDTH_THICK] = NSIntPixelsToTwips(5, pixelsToTwips);
    mWidthsInitialized = PR_TRUE;
  }

  // spacing values not inherited
  mOutlineRadius.Reset();

  nsStyleCoord  medium(NS_STYLE_BORDER_WIDTH_MEDIUM, eStyleUnit_Enumerated);
  mOutlineWidth = medium;
  mOutlineStyle = NS_STYLE_BORDER_STYLE_NONE;
  mOutlineColor = NS_RGB(0, 0, 0);

  mHasCachedOutline = PR_FALSE;
}

void StyleOutlineImpl::SetFrom(const nsStyleOutline& aSource)
{
  nsCRT::memcpy((nsStyleOutline*)this, &aSource, sizeof(nsStyleOutline));
}

void StyleOutlineImpl::CopyTo(nsStyleOutline& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStyleOutline*)this, sizeof(nsStyleOutline));
}

void StyleOutlineImpl::RecalcData(void)
{
  if ((NS_STYLE_BORDER_STYLE_NONE == GetOutlineStyle()) || 
      IsFixedUnit(mOutlineWidth.GetUnit(), PR_TRUE)) {
    if (NS_STYLE_BORDER_STYLE_NONE == GetOutlineStyle()) {
      mCachedOutlineWidth = 0;
    }
    else {
      mCachedOutlineWidth = CalcCoord(mOutlineWidth, mBorderWidths, 3);
    }
    mHasCachedOutline = PR_TRUE;
  }
  else {
    mHasCachedOutline = PR_FALSE;
  }
}

PRInt32 StyleOutlineImpl::CalcDifference(const StyleOutlineImpl& aOther) const
{
  if ((mOutlineWidth != aOther.mOutlineWidth) ||
      (mOutlineStyle != aOther.mOutlineStyle) ||
      (mOutlineColor != aOther.mOutlineColor) ||
      (mOutlineRadius != aOther.mOutlineRadius)) {
    return NS_STYLE_HINT_VISUAL;	// XXX: should be VISUAL: see bugs 9809 and 9816
  }
  return NS_STYLE_HINT_NONE;
}

PRUint32 StyleOutlineImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
  
#ifdef COMPUTE_STYLEDATA_CRC
  crc = StyleSideCRC(crc,&mOutlineRadius);
  crc = StyleCoordCRC(crc,&mOutlineWidth);
  crc = AccumulateCRC(crc,(const char *)&mHasCachedOutline,sizeof(mHasCachedOutline));
  crc = AccumulateCRC(crc,(const char *)&mCachedOutlineWidth,sizeof(mCachedOutlineWidth));
  crc = AccumulateCRC(crc,(const char *)&mOutlineStyle,sizeof(mOutlineStyle));
  crc = AccumulateCRC(crc,(const char *)&mOutlineColor,sizeof(mOutlineColor));
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif
// --------------------
// nsStyleList
//
nsStyleList::nsStyleList(void) { }
nsStyleList::~nsStyleList(void) { }

struct StyleListImpl: public nsStyleList {
  StyleListImpl(void) { }

  void ResetFrom(const nsStyleList* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleList& aSource);
  void CopyTo(nsStyleList& aDest) const;
  PRInt32 CalcDifference(const StyleListImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleListImpl(const StyleListImpl& aOther);
  StyleListImpl& operator=(const StyleListImpl& aOther);
};

void StyleListImpl::ResetFrom(const nsStyleList* aParent, nsIPresContext* aPresContext)
{
  if (nsnull != aParent) {
    mListStyleType = aParent->mListStyleType;
    mListStyleImage = aParent->mListStyleImage;
    mListStylePosition = aParent->mListStylePosition;
  }
  else {
    mListStyleType = NS_STYLE_LIST_STYLE_BASIC;
    mListStylePosition = NS_STYLE_LIST_STYLE_POSITION_OUTSIDE;
    mListStyleImage.Truncate();
  }
}

void StyleListImpl::SetFrom(const nsStyleList& aSource)
{
  mListStyleType = aSource.mListStyleType;
  mListStylePosition = aSource.mListStylePosition;
  mListStyleImage = aSource.mListStyleImage;
}

void StyleListImpl::CopyTo(nsStyleList& aDest) const
{
  aDest.mListStyleType = mListStyleType;
  aDest.mListStylePosition = mListStylePosition;
  aDest.mListStyleImage = mListStyleImage;
}

PRInt32 StyleListImpl::CalcDifference(const StyleListImpl& aOther) const
{
  if (mListStylePosition == aOther.mListStylePosition) {
    if (mListStyleImage == aOther.mListStyleImage) {
      if (mListStyleType == aOther.mListStyleType) {
        return NS_STYLE_HINT_NONE;
      }
      return NS_STYLE_HINT_REFLOW;
    }
    return NS_STYLE_HINT_REFLOW;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleListImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mListStyleType,sizeof(mListStyleType));
  crc = AccumulateCRC(crc,(const char *)&mListStylePosition,sizeof(mListStylePosition));
  crc = StyleStringCRC(crc,&mListStyleImage);
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

// --------------------
// nsStylePosition
//
nsStylePosition::nsStylePosition(void) { }
nsStylePosition::~nsStylePosition(void) { }

struct StylePositionImpl: public nsStylePosition {
  StylePositionImpl(void) { }

  void ResetFrom(const nsStylePosition* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStylePosition& aSource);
  void CopyTo(nsStylePosition& aDest) const;
  PRInt32 CalcDifference(const StylePositionImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StylePositionImpl(const StylePositionImpl& aOther);
  StylePositionImpl& operator=(const StylePositionImpl& aOther);
};

void StylePositionImpl::ResetFrom(const nsStylePosition* aParent, nsIPresContext* aPresContext)
{
  // positioning values not inherited
  mPosition = NS_STYLE_POSITION_NORMAL;
  nsStyleCoord  autoCoord(eStyleUnit_Auto);
  mOffset.SetLeft(autoCoord);
  mOffset.SetTop(autoCoord);
  mOffset.SetRight(autoCoord);
  mOffset.SetBottom(autoCoord);
  mWidth.SetAutoValue();
  mMinWidth.SetCoordValue(0);
  mMaxWidth.Reset();
  mHeight.SetAutoValue();
  mMinHeight.SetCoordValue(0);
  mMaxHeight.Reset();
  mBoxSizing = NS_STYLE_BOX_SIZING_CONTENT;
  mZIndex.SetAutoValue();
}

void StylePositionImpl::SetFrom(const nsStylePosition& aSource)
{
  nsCRT::memcpy((nsStylePosition*)this, &aSource, sizeof(nsStylePosition));
}

void StylePositionImpl::CopyTo(nsStylePosition& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStylePosition*)this, sizeof(nsStylePosition));
}

PRInt32 StylePositionImpl::CalcDifference(const StylePositionImpl& aOther) const
{
  if (mPosition == aOther.mPosition) {
    if ((mOffset == aOther.mOffset) &&
        (mWidth == aOther.mWidth) &&
        (mMinWidth == aOther.mMinWidth) &&
        (mMaxWidth == aOther.mMaxWidth) &&
        (mHeight == aOther.mHeight) &&
        (mMinHeight == aOther.mMinHeight) &&
        (mMaxHeight == aOther.mMaxHeight) &&
        (mBoxSizing == aOther.mBoxSizing) &&
        (mZIndex == aOther.mZIndex)) {
      return NS_STYLE_HINT_NONE;
    }
    return NS_STYLE_HINT_REFLOW;
  }
  return NS_STYLE_HINT_FRAMECHANGE;
}

PRUint32 StylePositionImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mPosition,sizeof(mPosition));
  crc = StyleSideCRC(crc,&mOffset);
  crc = StyleCoordCRC(crc,&mWidth);
  crc = StyleCoordCRC(crc,&mMinWidth);
  crc = StyleCoordCRC(crc,&mMaxWidth);
  crc = StyleCoordCRC(crc,&mHeight);
  crc = StyleCoordCRC(crc,&mMinHeight);
  crc = StyleCoordCRC(crc,&mMaxHeight);
  crc = AccumulateCRC(crc,(const char *)&mBoxSizing,sizeof(mBoxSizing));
  crc = AccumulateCRC(crc,(const char *)&mZIndex,sizeof(mZIndex));
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

// --------------------
// nsStyleText
//

nsStyleText::nsStyleText(void) { }
nsStyleText::~nsStyleText(void) { }

struct StyleTextImpl: public nsStyleText {
  StyleTextImpl(void) { }

  void ResetFrom(const nsStyleText* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleText& aSource);
  void CopyTo(nsStyleText& aDest) const;
  PRInt32 CalcDifference(const StyleTextImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleTextImpl(const StyleTextImpl& aOther);
  StyleTextImpl& operator=(const StyleTextImpl& aOther);
};

void StyleTextImpl::ResetFrom(const nsStyleText* aParent, nsIPresContext* aPresContext)
{
  // These properties not inherited
  mTextDecoration = NS_STYLE_TEXT_DECORATION_NONE;
  mVerticalAlign.SetIntValue(NS_STYLE_VERTICAL_ALIGN_BASELINE, eStyleUnit_Enumerated);
//  mVerticalAlign.Reset(); TBI

  if (nsnull != aParent) {
    mTextAlign = aParent->mTextAlign;
    mTextTransform = aParent->mTextTransform;
    mWhiteSpace = aParent->mWhiteSpace;
    mLetterSpacing = aParent->mLetterSpacing;

    // Inherit everything except percentage line-height values
    nsStyleUnit unit = aParent->mLineHeight.GetUnit();
    if ((eStyleUnit_Normal == unit) || (eStyleUnit_Factor == unit) ||
        (eStyleUnit_Coord == unit)) {
      mLineHeight = aParent->mLineHeight;
    }
    else {
      mLineHeight.SetInheritValue();
    }
    mTextIndent = aParent->mTextIndent;
    mWordSpacing = aParent->mWordSpacing;
#ifdef IBMBIDI
    mUnicodeBidi = aParent->mUnicodeBidi;
#endif // IBMBIDI
  }
  else {
    mTextAlign = NS_STYLE_TEXT_ALIGN_DEFAULT;
    mTextTransform = NS_STYLE_TEXT_TRANSFORM_NONE;
    mWhiteSpace = NS_STYLE_WHITESPACE_NORMAL;

    mLetterSpacing.SetNormalValue();
    mLineHeight.SetNormalValue();
    mTextIndent.SetCoordValue(0);
    mWordSpacing.SetNormalValue();
#ifdef IBMBIDI
    mUnicodeBidi = NS_STYLE_UNICODE_BIDI_INHERIT;
#endif // IBMBIDI
  }
}

void StyleTextImpl::SetFrom(const nsStyleText& aSource)
{
  nsCRT::memcpy((nsStyleText*)this, &aSource, sizeof(nsStyleText));
}

void StyleTextImpl::CopyTo(nsStyleText& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStyleText*)this, sizeof(nsStyleText));
}

PRInt32 StyleTextImpl::CalcDifference(const StyleTextImpl& aOther) const
{
  if ((mTextAlign == aOther.mTextAlign) &&
      (mTextTransform == aOther.mTextTransform) &&
      (mWhiteSpace == aOther.mWhiteSpace) &&
      (mLetterSpacing == aOther.mLetterSpacing) &&
      (mLineHeight == aOther.mLineHeight) &&
      (mTextIndent == aOther.mTextIndent) &&
      (mWordSpacing == aOther.mWordSpacing) &&
#ifdef IBMBIDI
      (mUnicodeBidi == aOther.mUnicodeBidi) &&
#endif // IBMBIDI
      (mVerticalAlign == aOther.mVerticalAlign)) {
    if (mTextDecoration == aOther.mTextDecoration) {
      return NS_STYLE_HINT_NONE;
    }
    return NS_STYLE_HINT_VISUAL;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleTextImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;

#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mTextAlign,sizeof(mTextAlign));
  crc = AccumulateCRC(crc,(const char *)&mTextDecoration,sizeof(mTextDecoration));
  crc = AccumulateCRC(crc,(const char *)&mTextTransform,sizeof(mTextTransform));
  crc = AccumulateCRC(crc,(const char *)&mWhiteSpace,sizeof(mWhiteSpace));
  crc = StyleCoordCRC(crc,&mLetterSpacing);
  crc = StyleCoordCRC(crc,&mLineHeight);
  crc = StyleCoordCRC(crc,&mTextIndent);
  crc = StyleCoordCRC(crc,&mWordSpacing);
  crc = StyleCoordCRC(crc,&mVerticalAlign);
#ifdef IBMBIDI
  crc = AccumulateCRC(crc,(const char *)&mUnicodeBidi,sizeof(mUnicodeBidi));
#endif // IBMBIDI
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

// --------------------
// nsStyleDisplay
//

struct StyleDisplayImpl: public nsStyleDisplay {
  StyleDisplayImpl(void) { }

  void ResetFrom(const nsStyleDisplay* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleDisplay& aSource);
  void CopyTo(nsStyleDisplay& aDest) const;
  PRInt32 CalcDifference(const StyleDisplayImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleDisplayImpl(const StyleDisplayImpl& aOther);
  StyleDisplayImpl& operator=(const StyleDisplayImpl& aOther);
};

void StyleDisplayImpl::ResetFrom(const nsStyleDisplay* aParent, nsIPresContext* aPresContext)
{
  if (nsnull != aParent) {
    mDirection = aParent->mDirection;
    mLanguage = aParent->mLanguage;
    mVisible = aParent->mVisible;
  }
  else {
#ifdef IBMBIDI
    PRUint32 mBidioptions;
    aPresContext->GetBidi(&mBidioptions);
    if (GET_BIDI_OPTION_DIRECTION(mBidioptions) == IBMBIDI_TEXTDIRECTION_RTL)
      mDirection = NS_STYLE_DIRECTION_RTL;
    else
      mDirection = NS_STYLE_DIRECTION_LTR;
#else // ifdef IBMBIDI
    aPresContext->GetDefaultDirection(&mDirection);
#endif // IBMBIDI
    aPresContext->GetLanguage(getter_AddRefs(mLanguage));
    mVisible = NS_STYLE_VISIBILITY_VISIBLE;
  }
  mDisplay = NS_STYLE_DISPLAY_INLINE;
  mFloats = NS_STYLE_FLOAT_NONE;
  mBreakType = NS_STYLE_CLEAR_NONE;
  mBreakBefore = PR_FALSE;
  mBreakAfter = PR_FALSE;
  mOverflow = NS_STYLE_OVERFLOW_VISIBLE;
  mClipFlags = NS_STYLE_CLIP_AUTO;
  mClip.SetRect(0,0,0,0);
#ifdef IBMBIDI
  mExplicitDirection = NS_STYLE_DIRECTION_INHERIT;
#endif // IBMBIDI
}

void StyleDisplayImpl::SetFrom(const nsStyleDisplay& aSource)
{
  mDirection = aSource.mDirection;
#ifdef IBMBIDI
  mExplicitDirection = aSource.mExplicitDirection;
#endif // IBMBIDI
  mDisplay = aSource.mDisplay;
  mFloats = aSource.mFloats;
  mBreakType = aSource.mBreakType;
  mBreakBefore = aSource.mBreakBefore;
  mBreakAfter = aSource.mBreakAfter;
  mVisible = aSource.mVisible;
  mOverflow = aSource.mOverflow;
  mClipFlags = aSource.mClipFlags;
  mClip = aSource.mClip;
  mLanguage = aSource.mLanguage;
}

void StyleDisplayImpl::CopyTo(nsStyleDisplay& aDest) const
{
  aDest.mDirection = mDirection;
#ifdef IBMBIDI
  aDest.mExplicitDirection = mExplicitDirection;
#endif // IBMBIDI
  aDest.mDisplay = mDisplay;
  aDest.mFloats = mFloats;
  aDest.mBreakType = mBreakType;
  aDest.mBreakBefore = mBreakBefore;
  aDest.mBreakAfter = mBreakAfter;
  aDest.mVisible = mVisible;
  aDest.mOverflow = mOverflow;
  aDest.mClipFlags = mClipFlags;
  aDest.mClip = mClip;
  aDest.mLanguage = mLanguage;
}

PRInt32 StyleDisplayImpl::CalcDifference(const StyleDisplayImpl& aOther) const
{
  if ((mDisplay == aOther.mDisplay) &&
      (mFloats == aOther.mFloats) &&
      (mOverflow == aOther.mOverflow)) {
    if ((mDirection == aOther.mDirection) &&
        (mLanguage == aOther.mLanguage) &&
        (mBreakType == aOther.mBreakType) &&
        (mBreakBefore == aOther.mBreakBefore) &&
        (mBreakAfter == aOther.mBreakAfter)) {
      if ((mVisible == aOther.mVisible) &&
          (mClipFlags == aOther.mClipFlags) &&
          (mClip == aOther.mClip)) {
        return NS_STYLE_HINT_NONE;
      }
      if ((mVisible != aOther.mVisible) && 
          ((NS_STYLE_VISIBILITY_COLLAPSE == mVisible) || 
           (NS_STYLE_VISIBILITY_COLLAPSE == aOther.mVisible))) {
        return NS_STYLE_HINT_REFLOW;
      }
      return NS_STYLE_HINT_VISUAL;
    }
    return NS_STYLE_HINT_REFLOW;
  }
  return NS_STYLE_HINT_FRAMECHANGE;
}

PRUint32 StyleDisplayImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mDirection,sizeof(mDirection));
#ifdef IBMBIDI
  crc = AccumulateCRC(crc,(const char *)&mExplicitDirection,sizeof(mExplicitDirection));
#endif // IBMBIDI
  crc = AccumulateCRC(crc,(const char *)&mDisplay,sizeof(mDisplay));
  crc = AccumulateCRC(crc,(const char *)&mFloats,sizeof(mFloats));
  crc = AccumulateCRC(crc,(const char *)&mBreakType,sizeof(mBreakType));
  crc = AccumulateCRC(crc,(const char *)&mBreakBefore,sizeof(mBreakBefore));
  crc = AccumulateCRC(crc,(const char *)&mBreakAfter,sizeof(mBreakAfter));
  crc = AccumulateCRC(crc,(const char *)&mVisible,sizeof(mVisible));
  crc = AccumulateCRC(crc,(const char *)&mOverflow,sizeof(mOverflow));
  crc = AccumulateCRC(crc,(const char *)&mClipFlags,sizeof(mClipFlags));
  // crc = StyleMarginCRC(crc,&mClip);
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

// --------------------
// nsStyleTable
//

nsStyleTable::nsStyleTable(void) { }
nsStyleTable::~nsStyleTable(void) { }

struct StyleTableImpl: public nsStyleTable {
  StyleTableImpl(void);

  void ResetFrom(const nsStyleTable* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleTable& aSource);
  void CopyTo(nsStyleTable& aDest) const;
  PRInt32 CalcDifference(const StyleTableImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleTableImpl(const StyleTableImpl& aOther);
  StyleTableImpl& operator=(const StyleTableImpl& aOther);
};

StyleTableImpl::StyleTableImpl()
{ 
  ResetFrom(nsnull, nsnull);
}

void StyleTableImpl::ResetFrom(const nsStyleTable* aParent, nsIPresContext* aPresContext)
{
  // values not inherited
  mLayoutStrategy = NS_STYLE_TABLE_LAYOUT_AUTO;
  mCols  = NS_STYLE_TABLE_COLS_NONE;
  mFrame = NS_STYLE_TABLE_FRAME_NONE;
  mRules = NS_STYLE_TABLE_RULES_ALL;
  mCellPadding.Reset();
  mSpan = 1;

  if (aParent) {  // handle inherited properties
    mBorderCollapse = aParent->mBorderCollapse;
    mEmptyCells     = aParent->mEmptyCells;
    mCaptionSide    = aParent->mCaptionSide;
    mBorderSpacingX = aParent->mBorderSpacingX;
    mBorderSpacingY = aParent->mBorderSpacingY;
    mSpanWidth      = aParent->mSpanWidth;
  }
  else {
    mBorderCollapse = NS_STYLE_BORDER_SEPARATE;

    nsCompatibility compatMode = eCompatibility_Standard;
    if (aPresContext) {
		  aPresContext->GetCompatibilityMode(&compatMode);
		}
    mEmptyCells = (compatMode == eCompatibility_NavQuirks
                    ? NS_STYLE_TABLE_EMPTY_CELLS_HIDE     // bug 33244
                    : NS_STYLE_TABLE_EMPTY_CELLS_SHOW);

    mCaptionSide = NS_SIDE_TOP;
    mBorderSpacingX.Reset();
    mBorderSpacingY.Reset();
    mSpanWidth.Reset();
  }
}

void StyleTableImpl::SetFrom(const nsStyleTable& aSource)
{
  nsCRT::memcpy((nsStyleTable*)this, &aSource, sizeof(nsStyleTable));
}

void StyleTableImpl::CopyTo(nsStyleTable& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStyleTable*)this, sizeof(nsStyleTable));
}

PRInt32 StyleTableImpl::CalcDifference(const StyleTableImpl& aOther) const
{
  if ((mLayoutStrategy == aOther.mLayoutStrategy) &&
      (mFrame == aOther.mFrame) &&
      (mRules == aOther.mRules) &&
      (mBorderCollapse == aOther.mBorderCollapse) &&
      (mBorderSpacingX == aOther.mBorderSpacingX) &&
      (mBorderSpacingY == aOther.mBorderSpacingY) &&
      (mCellPadding == aOther.mCellPadding) &&
      (mCaptionSide == aOther.mCaptionSide) &&
      (mCols == aOther.mCols) &&
      (mSpan == aOther.mSpan) &&
      (mSpanWidth == aOther.mSpanWidth)) {
    if (mEmptyCells == aOther.mEmptyCells) {
      return NS_STYLE_HINT_NONE;
    }
    return NS_STYLE_HINT_VISUAL;
  }
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleTableImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mLayoutStrategy,sizeof(mLayoutStrategy));
  crc = AccumulateCRC(crc,(const char *)&mFrame,sizeof(mFrame));
  crc = AccumulateCRC(crc,(const char *)&mRules,sizeof(mRules));
  crc = AccumulateCRC(crc,(const char *)&mBorderCollapse,sizeof(mBorderCollapse));
  crc = StyleCoordCRC(crc,&mBorderSpacingX);
  crc = StyleCoordCRC(crc,&mBorderSpacingY);
  crc = StyleCoordCRC(crc,&mCellPadding);
  crc = AccumulateCRC(crc,(const char *)&mCaptionSide,sizeof(mCaptionSide));
  crc = AccumulateCRC(crc,(const char *)&mEmptyCells,sizeof(mEmptyCells));
  crc = AccumulateCRC(crc,(const char *)&mCols,sizeof(mCols));
  crc = AccumulateCRC(crc,(const char *)&mSpan,sizeof(mSpan));
  crc = StyleCoordCRC(crc,&mSpanWidth);
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

//-----------------------
// nsStyleContent
//

nsStyleContent::nsStyleContent(void)
  : mMarkerOffset(),
    mContentCount(0),
    mContents(nsnull),
    mIncrementCount(0),
    mIncrements(nsnull),
    mResetCount(0),
    mResets(nsnull),
    mQuotesCount(0),
    mQuotes(nsnull)
{
}

nsStyleContent::~nsStyleContent(void)
{
  DELETE_ARRAY_IF(mContents);
  DELETE_ARRAY_IF(mIncrements);
  DELETE_ARRAY_IF(mResets);
  DELETE_ARRAY_IF(mQuotes);
}


struct StyleContentImpl: public nsStyleContent {
  StyleContentImpl(void) : nsStyleContent() { };

  void ResetFrom(const StyleContentImpl* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleContent& aSource);
  void CopyTo(nsStyleContent& aDest) const;
  PRInt32 CalcDifference(const StyleContentImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleContentImpl(const StyleContentImpl& aOther);
  StyleContentImpl& operator=(const StyleContentImpl& aOther);
};

void
StyleContentImpl::ResetFrom(const StyleContentImpl* aParent, nsIPresContext* aPresContext)
{
  // reset data
  mMarkerOffset.Reset();
  mContentCount = 0;
  DELETE_ARRAY_IF(mContents);
  mIncrementCount = 0;
  DELETE_ARRAY_IF(mIncrements);
  mResetCount = 0;
  DELETE_ARRAY_IF(mResets);

  // inherited data
  if (aParent) {
    if (NS_SUCCEEDED(AllocateQuotes(aParent->mQuotesCount))) {
      PRUint32 ix = (mQuotesCount * 2);
      while (0 < ix--) {
        mQuotes[ix] = aParent->mQuotes[ix];
      }
    }
  }
  else {
    mQuotesCount = 0;
    DELETE_ARRAY_IF(mQuotes);
  }
}

void StyleContentImpl::SetFrom(const nsStyleContent& aSource)
{
  mMarkerOffset = aSource.mMarkerOffset;

  PRUint32 index;
  if (NS_SUCCEEDED(AllocateContents(aSource.ContentCount()))) {
    for (index = 0; index < mContentCount; index++) {
      aSource.GetContentAt(index, mContents[index].mType, mContents[index].mContent);
    }
  }

  if (NS_SUCCEEDED(AllocateCounterIncrements(aSource.CounterIncrementCount()))) {
    for (index = 0; index < mIncrementCount; index++) {
      aSource.GetCounterIncrementAt(index, mIncrements[index].mCounter,
                                           mIncrements[index].mValue);
    }
  }

  if (NS_SUCCEEDED(AllocateCounterResets(aSource.CounterResetCount()))) {
    for (index = 0; index < mResetCount; index++) {
      aSource.GetCounterResetAt(index, mResets[index].mCounter,
                                       mResets[index].mValue);
    }
  }

  if (NS_SUCCEEDED(AllocateQuotes(aSource.QuotesCount()))) {
    PRUint32 count = (mQuotesCount * 2);
    for (index = 0; index < count; index += 2) {
      aSource.GetQuotesAt(index, mQuotes[index], mQuotes[index + 1]);
    }
  }
}

void StyleContentImpl::CopyTo(nsStyleContent& aDest) const
{
  aDest.mMarkerOffset = mMarkerOffset;

  PRUint32 index;
  if (NS_SUCCEEDED(aDest.AllocateContents(mContentCount))) {
    for (index = 0; index < mContentCount; index++) {
      aDest.SetContentAt(index, mContents[index].mType,
                                mContents[index].mContent);
    }
  }

  if (NS_SUCCEEDED(aDest.AllocateCounterIncrements(mIncrementCount))) {
    for (index = 0; index < mIncrementCount; index++) {
      aDest.SetCounterIncrementAt(index, mIncrements[index].mCounter,
                                         mIncrements[index].mValue);
    }
  }

  if (NS_SUCCEEDED(aDest.AllocateCounterResets(mResetCount))) {
    for (index = 0; index < mResetCount; index++) {
      aDest.SetCounterResetAt(index, mResets[index].mCounter,
                                     mResets[index].mValue);
    }
  }

  if (NS_SUCCEEDED(aDest.AllocateQuotes(mQuotesCount))) {
    PRUint32 count = (mQuotesCount * 2);
    for (index = 0; index < count; index += 2) {
      aDest.SetQuotesAt(index, mQuotes[index], mQuotes[index + 1]);
    }
  }
}

PRInt32 
StyleContentImpl::CalcDifference(const StyleContentImpl& aOther) const
{
  if (mContentCount == aOther.mContentCount) {
    if ((mMarkerOffset == aOther.mMarkerOffset) &&
        (mIncrementCount == aOther.mIncrementCount) && 
        (mResetCount == aOther.mResetCount) &&
        (mQuotesCount == aOther.mQuotesCount)) {
      PRUint32 ix = mContentCount;
      while (0 < ix--) {
        if ((mContents[ix].mType != aOther.mContents[ix].mType) || 
            (mContents[ix].mContent != aOther.mContents[ix].mContent)) {
          return NS_STYLE_HINT_REFLOW;
        }
      }
      ix = mIncrementCount;
      while (0 < ix--) {
        if ((mIncrements[ix].mValue != aOther.mIncrements[ix].mValue) || 
            (mIncrements[ix].mCounter != aOther.mIncrements[ix].mCounter)) {
          return NS_STYLE_HINT_REFLOW;
        }
      }
      ix = mResetCount;
      while (0 < ix--) {
        if ((mResets[ix].mValue != aOther.mResets[ix].mValue) || 
            (mResets[ix].mCounter != aOther.mResets[ix].mCounter)) {
          return NS_STYLE_HINT_REFLOW;
        }
      }
      ix = (mQuotesCount * 2);
      while (0 < ix--) {
        if (mQuotes[ix] != aOther.mQuotes[ix]) {
          return NS_STYLE_HINT_REFLOW;
        }
      }
      return NS_STYLE_HINT_NONE;
    }
    return NS_STYLE_HINT_REFLOW;
  }
  return NS_STYLE_HINT_FRAMECHANGE;
}

PRUint32 StyleContentImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = StyleCoordCRC(crc,&mMarkerOffset);
  crc = AccumulateCRC(crc,(const char *)&mContentCount,sizeof(mContentCount));

  crc = AccumulateCRC(crc,(const char *)&mIncrementCount,sizeof(mIncrementCount));
  crc = AccumulateCRC(crc,(const char *)&mResetCount,sizeof(mResetCount));
  crc = AccumulateCRC(crc,(const char *)&mQuotesCount,sizeof(mQuotesCount));
  if (mContents) {
    crc = AccumulateCRC(crc,(const char *)&(mContents->mType),sizeof(mContents->mType));
  }
  if (mIncrements) {
    crc = AccumulateCRC(crc,(const char *)&(mIncrements->mValue),sizeof(mIncrements->mValue));
  }
  if (mResets) {
    crc = AccumulateCRC(crc,(const char *)&(mResets->mValue),sizeof(mResets->mValue));
  }
  if (mQuotes) {
    crc = StyleStringCRC(crc,mQuotes);
  }
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

//-----------------------
// nsStyleUserInterface
//

nsStyleUserInterface::nsStyleUserInterface(void) { }
nsStyleUserInterface::~nsStyleUserInterface(void) { }

struct StyleUserInterfaceImpl: public nsStyleUserInterface {
  StyleUserInterfaceImpl(void)  { }

  void ResetFrom(const nsStyleUserInterface* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleUserInterface& aSource);
  void CopyTo(nsStyleUserInterface& aDest) const;
  PRInt32 CalcDifference(const StyleUserInterfaceImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleUserInterfaceImpl(const StyleUserInterfaceImpl& aOther);
  StyleUserInterfaceImpl& operator=(const StyleUserInterfaceImpl& aOther);
};

void StyleUserInterfaceImpl::ResetFrom(const nsStyleUserInterface* aParent, nsIPresContext* aPresContext)
{
  if (aParent) {
    mUserInput = aParent->mUserInput;
    mUserModify = aParent->mUserModify;
    mUserFocus = aParent->mUserFocus;
  }
  else {
    mUserInput = NS_STYLE_USER_INPUT_AUTO;
    mUserModify = NS_STYLE_USER_MODIFY_READ_ONLY;
    mUserFocus = NS_STYLE_USER_FOCUS_NONE;
  }

  mUserSelect = NS_STYLE_USER_SELECT_AUTO;
  mKeyEquivalent = PRUnichar(0); // XXX what type should this be?
  mResizer = NS_STYLE_RESIZER_AUTO;
  mBehavior.SetLength(0);
}

void StyleUserInterfaceImpl::SetFrom(const nsStyleUserInterface& aSource)
{
  mUserInput = aSource.mUserInput;
  mUserModify = aSource.mUserModify;
  mUserFocus = aSource.mUserFocus;

  mUserSelect = aSource.mUserSelect;
  mKeyEquivalent = aSource.mKeyEquivalent;
  mResizer = aSource.mResizer;
  mBehavior = aSource.mBehavior;
}

void StyleUserInterfaceImpl::CopyTo(nsStyleUserInterface& aDest) const
{
  aDest.mUserInput = mUserInput;
  aDest.mUserModify = mUserModify;
  aDest.mUserFocus = mUserFocus;

  aDest.mUserSelect = mUserSelect;
  aDest.mKeyEquivalent = mKeyEquivalent;
  aDest.mResizer = mResizer;
  aDest.mBehavior = mBehavior;
}

PRInt32 StyleUserInterfaceImpl::CalcDifference(const StyleUserInterfaceImpl& aOther) const
{
  if (mBehavior != aOther.mBehavior)
    return NS_STYLE_HINT_FRAMECHANGE;

  if ((mUserInput == aOther.mUserInput) && 
      (mResizer == aOther.mResizer)) {
    if ((mUserModify == aOther.mUserModify) && 
        (mUserSelect == aOther.mUserSelect)) {
      if ((mKeyEquivalent == aOther.mKeyEquivalent) &&
          (mUserFocus == aOther.mUserFocus) &&
          (mResizer == aOther.mResizer)) {
        return NS_STYLE_HINT_NONE;
      }
      return NS_STYLE_HINT_CONTENT;
    }
    return NS_STYLE_HINT_VISUAL;
  }
  if ((mUserInput != aOther.mUserInput) &&
      ((NS_STYLE_USER_INPUT_NONE == mUserInput) || 
       (NS_STYLE_USER_INPUT_NONE == aOther.mUserInput))) {
    return NS_STYLE_HINT_FRAMECHANGE;
  }
  return NS_STYLE_HINT_VISUAL;
}

PRUint32 StyleUserInterfaceImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mUserInput,sizeof(mUserInput));
  crc = AccumulateCRC(crc,(const char *)&mUserModify,sizeof(mUserModify));
  crc = AccumulateCRC(crc,(const char *)&mUserSelect,sizeof(mUserSelect));
  crc = AccumulateCRC(crc,(const char *)&mUserFocus,sizeof(mUserFocus));
  crc = AccumulateCRC(crc,(const char *)&mKeyEquivalent,sizeof(mKeyEquivalent));
  crc = AccumulateCRC(crc,(const char *)&mResizer,sizeof(mResizer));
  PRUint32 len;
  len = mBehavior.Length();
  crc = AccumulateCRC(crc,(const char *)&len,sizeof(len));
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

//-----------------------
// nsStylePrint
//

nsStylePrint::nsStylePrint(void) { }
nsStylePrint::~nsStylePrint(void) { }

struct StylePrintImpl: public nsStylePrint {
  StylePrintImpl(void)  { }

  void ResetFrom(const nsStylePrint* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStylePrint& aSource);
  void CopyTo(nsStylePrint& aDest) const;
  PRInt32 CalcDifference(const StylePrintImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StylePrintImpl(const StylePrintImpl& aOther);
  StylePrintImpl& operator=(const StylePrintImpl& aOther);
};

void StylePrintImpl::ResetFrom(const nsStylePrint* aParent, nsIPresContext* aPresContext)
{
  if (aParent) {
    mPageBreakBefore = aParent->mPageBreakBefore;
    mPageBreakAfter = aParent->mPageBreakAfter;
    mPageBreakInside = aParent->mPageBreakInside;
    mWidows = aParent->mWidows;
    mOrphans = aParent->mOrphans;
		mMarks = aParent->mMarks;
		mSizeWidth = aParent->mSizeWidth;
		mSizeHeight = aParent->mSizeHeight;
  }
  else {
    mPageBreakBefore = NS_STYLE_PAGE_BREAK_AUTO;
    mPageBreakAfter = NS_STYLE_PAGE_BREAK_AUTO;
    mPageBreakInside = NS_STYLE_PAGE_BREAK_AUTO;
    mWidows = 2;
    mOrphans = 2;
		mMarks = NS_STYLE_PAGE_MARKS_NONE;
		mSizeWidth.SetAutoValue();
		mSizeHeight.SetAutoValue();
  }
}

void StylePrintImpl::SetFrom(const nsStylePrint& aSource)
{
  nsCRT::memcpy((nsStylePrint*)this, &aSource, sizeof(nsStylePrint));
}

void StylePrintImpl::CopyTo(nsStylePrint& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStylePrint*)this, sizeof(nsStylePrint));
}

PRInt32 StylePrintImpl::CalcDifference(const StylePrintImpl& aOther) const
{
	if ((mPageBreakBefore == aOther.mPageBreakBefore)
	&& (mPageBreakAfter == aOther.mPageBreakAfter)
	&& (mPageBreakInside == aOther.mPageBreakInside)
	&& (mWidows == aOther.mWidows)
	&& (mOrphans == aOther.mOrphans)
	&& (mMarks == aOther.mMarks)
	&& (mSizeWidth == aOther.mSizeWidth)
	&& (mSizeHeight == aOther.mSizeHeight)) {
  	return NS_STYLE_HINT_NONE;
	}

	if (mMarks != aOther.mMarks) {
  	return NS_STYLE_HINT_VISUAL;
	}
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StylePrintImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mPageBreakBefore,sizeof(mPageBreakBefore));
  crc = AccumulateCRC(crc,(const char *)&mPageBreakAfter,sizeof(mPageBreakAfter));
  crc = AccumulateCRC(crc,(const char *)&mPageBreakInside,sizeof(mPageBreakInside));
  PRUint32 len = mPage.Length();
  crc = AccumulateCRC(crc,(const char *)&len,sizeof(len));
  crc = AccumulateCRC(crc,(const char *)&mWidows,sizeof(mWidows));
  crc = AccumulateCRC(crc,(const char *)&mOrphans,sizeof(mOrphans));
  crc = AccumulateCRC(crc,(const char *)&mMarks,sizeof(mMarks));
  crc = StyleCoordCRC(crc,&mSizeWidth);
  crc = StyleCoordCRC(crc,&mSizeHeight);
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif

#ifdef INCLUDE_XUL
// --------------------
// nsStyleXUL
//
nsStyleXUL::nsStyleXUL() { }
nsStyleXUL::~nsStyleXUL() { }

struct StyleXULImpl: public nsStyleXUL {
  StyleXULImpl() { }

  void ResetFrom(const nsStyleXUL* aParent, nsIPresContext* aPresContext);
  void SetFrom(const nsStyleXUL& aSource);
  void CopyTo(nsStyleXUL& aDest) const;
  PRInt32 CalcDifference(const StyleXULImpl& aOther) const;
  PRUint32 ComputeCRC32(PRUint32 aCrc) const;

private:  // These are not allowed
  StyleXULImpl(const StyleXULImpl& aOther);
  StyleXULImpl& operator=(const StyleXULImpl& aOther);
};

void StyleXULImpl::ResetFrom(const nsStyleXUL* aParent, nsIPresContext* aPresContext)
{
  mBoxOrient = NS_STYLE_BOX_ORIENT_HORIZONTAL;
}

void StyleXULImpl::SetFrom(const nsStyleXUL& aSource)
{
  nsCRT::memcpy((nsStyleXUL*)this, &aSource, sizeof(nsStyleXUL));
}

void StyleXULImpl::CopyTo(nsStyleXUL& aDest) const
{
  nsCRT::memcpy(&aDest, (const nsStyleXUL*)this, sizeof(nsStyleXUL));
}

PRInt32 StyleXULImpl::CalcDifference(const StyleXULImpl& aOther) const
{
  if (mBoxOrient == aOther.mBoxOrient)
    return NS_STYLE_HINT_NONE;
  return NS_STYLE_HINT_REFLOW;
}

PRUint32 StyleXULImpl::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;
#ifdef COMPUTE_STYLEDATA_CRC
  crc = AccumulateCRC(crc,(const char *)&mBoxOrient,sizeof(mBoxOrient));
#endif
  return crc;
}

#ifdef XP_MAC
#pragma mark -
#endif
#endif // INCLUDE_XUL

//----------------------------------------------------------------------

#ifdef SHARE_STYLECONTEXTS

//========================
#ifdef DEBUG
// define this to get stats on the use of the |nsStyleStruct|s inside a |nsStyleContextData|. //XXX pierre 
//#define LOG_STYLE_STRUCTS
#endif

#ifdef LOG_STYLE_STRUCTS
//  StyleFontImpl           mFont;
struct StyleFontImplLog: public StyleFontImpl {
  StyleFontImplLog(const nsFont& aVariableFont, const nsFont& aFixedFont)
    : StyleFontImpl(aVariableFont, aFixedFont),
    mInternalFont(aVariableFont, aFixedFont)
  {}
  void ResetFrom(const nsStyleFont* aParent, nsIPresContext* aPresContext);
  StyleFontImpl mInternalFont;
  bool mSetFromParent;
};

void StyleFontImplLog::ResetFrom(const nsStyleFont* aParent, nsIPresContext* aPresContext)
{
	StyleFontImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalFont);
	mSetFromParent = (aParent != nsnull);
}

//  StyleColorImpl          mColor;
struct StyleColorImplLog: public StyleColorImpl {
  void ResetFrom(const nsStyleColor* aParent, nsIPresContext* aPresContext);
  StyleColorImpl mInternalColor;
  bool mSetFromParent;
};

void StyleColorImplLog::ResetFrom(const nsStyleColor* aParent, nsIPresContext* aPresContext)
{
	StyleColorImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalColor);
	mSetFromParent = (aParent != nsnull);
}

//  StyleListImpl           mList;
struct StyleListImplLog: public StyleListImpl {
  void ResetFrom(const nsStyleList* aParent, nsIPresContext* aPresContext);
  StyleListImpl mInternalList;
  bool mSetFromParent;
};

void StyleListImplLog::ResetFrom(const nsStyleList* aParent, nsIPresContext* aPresContext)
{
	StyleListImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalList);
	mSetFromParent = (aParent != nsnull);
}

//  StylePositionImpl       mPosition;
struct StylePositionImplLog: public StylePositionImpl {
  void ResetFrom(const nsStylePosition* aParent, nsIPresContext* aPresContext);
  StylePositionImpl mInternalPosition;
  bool mSetFromParent;
};

void StylePositionImplLog::ResetFrom(const nsStylePosition* aParent, nsIPresContext* aPresContext)
{
	StylePositionImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalPosition);
	mSetFromParent = (aParent != nsnull);
}

//  StyleTextImpl           mText;
struct StyleTextImplLog: public StyleTextImpl {
  void ResetFrom(const nsStyleText* aParent, nsIPresContext* aPresContext);
  StyleTextImpl mInternalText;
  bool mSetFromParent;
};

void StyleTextImplLog::ResetFrom(const nsStyleText* aParent, nsIPresContext* aPresContext)
{
	StyleTextImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalText);
	mSetFromParent = (aParent != nsnull);
}

//  StyleDisplayImpl        mDisplay;
struct StyleDisplayImplLog: public StyleDisplayImpl {
  void ResetFrom(const nsStyleDisplay* aParent, nsIPresContext* aPresContext);
  StyleDisplayImpl mInternalDisplay;
  bool mSetFromParent;
};

void StyleDisplayImplLog::ResetFrom(const nsStyleDisplay* aParent, nsIPresContext* aPresContext)
{
	StyleDisplayImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalDisplay);
	mSetFromParent = (aParent != nsnull);
}

//  StyleTableImpl          mTable;
struct StyleTableImplLog: public StyleTableImpl {
  void ResetFrom(const nsStyleTable* aParent, nsIPresContext* aPresContext);
  StyleTableImpl mInternalTable;
  bool mSetFromParent;
};

void StyleTableImplLog::ResetFrom(const nsStyleTable* aParent, nsIPresContext* aPresContext)
{
	StyleTableImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalTable);
	mSetFromParent = (aParent != nsnull);
}

//  StyleContentImpl        mContent;
struct StyleContentImplLog: public StyleContentImpl {
  void ResetFrom(const StyleContentImpl* aParent, nsIPresContext* aPresContext);
  StyleContentImpl mInternalContent;
  bool mSetFromParent;
};

void StyleContentImplLog::ResetFrom(const StyleContentImpl* aParent, nsIPresContext* aPresContext)
{
	StyleContentImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalContent);
	mSetFromParent = (aParent != nsnull);
}

//  StyleUserInterfaceImpl  mUserInterface;
struct StyleUserInterfaceImplLog: public StyleUserInterfaceImpl {
  void ResetFrom(const nsStyleUserInterface* aParent, nsIPresContext* aPresContext);
  StyleUserInterfaceImpl mInternalUserInterface;
  bool mSetFromParent;
};

void StyleUserInterfaceImplLog::ResetFrom(const nsStyleUserInterface* aParent, nsIPresContext* aPresContext)
{
	StyleUserInterfaceImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalUserInterface);
	mSetFromParent = (aParent != nsnull);
}

//	StylePrintImpl					mPrint;
struct StylePrintImplLog: public StylePrintImpl {
  void ResetFrom(const nsStylePrint* aParent, nsIPresContext* aPresContext);
  StylePrintImpl mInternalPrint;
  bool mSetFromParent;
};

void StylePrintImplLog::ResetFrom(const nsStylePrint* aParent, nsIPresContext* aPresContext)
{
	StylePrintImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalPrint);
	mSetFromParent = (aParent != nsnull);
}

//	StyleMarginImpl					mMargin;
struct StyleMarginImplLog: public StyleMarginImpl {
  void ResetFrom(const nsStyleMargin* aParent, nsIPresContext* aPresContext);
  StyleMarginImpl mInternalMargin;
  bool mSetFromParent;
};

void StyleMarginImplLog::ResetFrom(const nsStyleMargin* aParent, nsIPresContext* aPresContext)
{
	StyleMarginImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalMargin);
	mSetFromParent = (aParent != nsnull);
}

//	StylePaddingImpl				mPadding;
struct StylePaddingImplLog: public StylePaddingImpl {
  void ResetFrom(const nsStylePadding* aParent, nsIPresContext* aPresContext);
  StylePaddingImpl mInternalPadding;
  bool mSetFromParent;
};

void StylePaddingImplLog::ResetFrom(const nsStylePadding* aParent, nsIPresContext* aPresContext)
{
	StylePaddingImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalPadding);
	mSetFromParent = (aParent != nsnull);
}

//	StyleBorderImpl					mBorder;
struct StyleBorderImplLog: public StyleBorderImpl {
  void ResetFrom(const nsStyleBorder* aParent, nsIPresContext* aPresContext);
  StyleBorderImpl mInternalBorder;
  bool mSetFromParent;
};

void StyleBorderImplLog::ResetFrom(const nsStyleBorder* aParent, nsIPresContext* aPresContext)
{
	StyleBorderImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalBorder);
	mSetFromParent = (aParent != nsnull);
}

//	StyleOutlineImpl				mOutline;
struct StyleOutlineImplLog: public StyleOutlineImpl {
  void ResetFrom(const nsStyleOutline* aParent, nsIPresContext* aPresContext);
  StyleOutlineImpl mInternalOutline;
  bool mSetFromParent;
};

void StyleOutlineImplLog::ResetFrom(const nsStyleOutline* aParent, nsIPresContext* aPresContext)
{
	StyleOutlineImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalOutline);
	mSetFromParent = (aParent != nsnull);
}

#ifdef INCLUDE_XUL
//  StyleXULImpl       mXUL;
struct StyleXULImplLog: public StyleXULImpl {
  void ResetFrom(const nsStyleXUL* aParent, nsIPresContext* aPresContext);
  StyleXULImpl mInternalXUL;
  bool mSetFromParent;
};

void StyleXULImplLog::ResetFrom(const nsStyleXUL* aParent, nsIPresContext* aPresContext)
{
	StyleXULImpl::ResetFrom(aParent, aPresContext);
	CopyTo(mInternalXUL);
	mSetFromParent = (aParent != nsnull);
}
#endif // INCLUDE_XUL

#ifdef XP_MAC
#pragma mark -
#endif

#endif // LOG_STYLE_STRUCTS
//========================

class nsStyleContextData
{
public:

  friend class StyleContextImpl;

  void SizeOf(nsISizeOfHandler *aSizeOfHandler, PRUint32 &aSize);

#ifdef LOG_STYLE_STRUCTS
public:
#else
private:  // all data and methods private: only friends have access
#endif

  static nsStyleContextData *Create(nsIPresContext *aPresContext);
  
  nsStyleContextData(nsIPresContext *aPresContext);
  ~nsStyleContextData(void);

  PRUint32 ComputeCRC32(PRUint32 aCrc) const;
  void SetCRC32(void) { 
    mCRC = ComputeCRC32(0); 
    if (mCRC==STYLEDATA_NO_CRC) 
      mCRC = STYLEDATA_DEFAULT_CRC; 
  }
  PRUint32 GetCRC32(void) const { return mCRC; }

  PRUint32 AddRef(void);
  PRUint32 Release(void);

  // the style data...
  // - StyleContextImpl gets friend-access
  //
#ifdef LOG_STYLE_STRUCTS
  StyleFontImplLog           mFont;
  StyleColorImplLog          mColor;
  StyleListImplLog           mList;
  StylePositionImplLog       mPosition;
  StyleTextImplLog           mText;
  StyleDisplayImplLog        mDisplay;
  StyleTableImplLog          mTable;
  StyleContentImplLog        mContent;
  StyleUserInterfaceImplLog  mUserInterface;
	StylePrintImplLog					 mPrint;
	StyleMarginImplLog	 			 mMargin;
	StylePaddingImplLog				 mPadding;
	StyleBorderImplLog				 mBorder;
	StyleOutlineImplLog				 mOutline;
#ifdef INCLUDE_XUL
  StyleXULImplLog            mXUL;
#endif
#else
  StyleFontImpl           mFont;
  StyleColorImpl          mColor;
  StyleListImpl           mList;
  StylePositionImpl       mPosition;
  StyleTextImpl           mText;
  StyleDisplayImpl        mDisplay;
  StyleTableImpl          mTable;
  StyleContentImpl        mContent;
  StyleUserInterfaceImpl  mUserInterface;
	StylePrintImpl					mPrint;
	StyleMarginImpl					mMargin;
	StylePaddingImpl				mPadding;
	StyleBorderImpl					mBorder;
	StyleOutlineImpl				mOutline;
#ifdef INCLUDE_XUL
  StyleXULImpl            mXUL;
#endif
#endif

  PRUint32                mRefCnt;
  PRUint32                mCRC;

#ifdef DEBUG
  static PRUint32         gInstanceCount;
#endif
};

#ifndef DEBUG
inline
#endif
PRUint32 nsStyleContextData::AddRef(void)
{
  ++mRefCnt;
  NS_LOG_ADDREF(this,mRefCnt,"nsStyleContextData",sizeof(*this));
  return mRefCnt;
}

#ifndef DEBUG
inline
#endif
PRUint32 nsStyleContextData::Release(void)
{
  NS_ASSERTION(mRefCnt > 0, "RefCount error in nsStyleContextData");
  --mRefCnt;
  NS_LOG_RELEASE(this,mRefCnt,"nsStyleContextData");
  if (0 == mRefCnt) {
#ifdef NOISY_DEBUG
    printf("deleting nsStyleContextData instance: (%ld)\n", (long)(--gInstanceCount));
#endif
    delete this;
    return 0;
  }
  return mRefCnt;
}

#ifdef DEBUG
/*static*/ PRUint32 nsStyleContextData::gInstanceCount;
#endif  // DEBUG

nsStyleContextData *nsStyleContextData::Create(nsIPresContext *aPresContext)
{
  NS_ASSERTION(aPresContext != nsnull, "parameter cannot be null");
  nsStyleContextData *pData = nsnull;
  if (aPresContext) {
    pData = new nsStyleContextData(aPresContext);
    if (pData) {
      NS_ADDREF(pData);
#ifdef NOISY_DEBUG
      printf("new nsStyleContextData instance: (%ld) CRC=%lu\n", 
             (long)(++gInstanceCount), (unsigned long)pData->ComputeCRC32(0));
#endif // NOISY_DEBUG
    }
  }
  return pData;
}

nsStyleContextData::nsStyleContextData(nsIPresContext *aPresContext)
: mFont(aPresContext->GetDefaultFontDeprecated(), 
        aPresContext->GetDefaultFixedFontDeprecated()),
  mRefCnt(0), mCRC(0)
{
}

//=========================================================================================================

#ifdef LOG_STYLE_STRUCTS  //XXX pierre

#ifdef XP_MAC
#include <Events.h>
static bool MacKeyDown(unsigned char theKey)
{
	KeyMap map;
	GetKeys(map);
	return ((*((unsigned char *)map + (theKey >> 3)) >> (theKey & 7)) & 1) != 0;
}
#endif


static bool IsTimeToDumpStyleStructs()
{
  bool timeToDump = false;
#ifdef XP_MAC
	static unsigned long lastTicks = 0;
  if (MacKeyDown(0x3b)) { // control key
    if ((unsigned long)(::TickCount() - lastTicks) > 60) {
	    lastTicks = ::TickCount();
	    timeToDump = true;
	  }
	}
#endif
  return timeToDump;
}
static void LogStyleStructs(nsStyleContextData* aStyleContextData)
{
#define max_structs eStyleStruct_Max

  static unsigned long totalCount = 0;
  static unsigned long defaultStruct[max_structs];
  static unsigned long setFromParent[max_structs];

	static bool resetCounters = true;

  if (IsTimeToDumpStyleStructs()) {
    resetCounters = true;
    printf("\n\n\n");
    printf("-------------------------------------------------------------------------------------------------------------\n");
    printf("Count of nsStyleContextData: %ld\n", totalCount);
    printf("-------------------------------------------------------------------------------------------------------------\n");
	  printf("                                unchanged   unchanged%c   set-from-parent%c   size-of-struct  potential-gain-Kb\n", '%', '%');
    unsigned long totalFootprint = 0;
    unsigned long totalPotentialGain = 0;
    for (short i = 0; i < max_structs; i ++) {
      short index = i+1;
      short sizeOfStruct = 0;
      unsigned long footprint = 0;
      unsigned long potentialGain = 0;
      switch (index) {
		    case eStyleStruct_Font:      			printf("eStyleStruct_Font           "); sizeOfStruct = sizeof(StyleFontImpl);  break;
		    case eStyleStruct_Color:      		printf("eStyleStruct_Color          "); sizeOfStruct = sizeof(StyleColorImpl);  break;
		    case eStyleStruct_List:      			printf("eStyleStruct_List           "); sizeOfStruct = sizeof(StyleListImpl);  break;
		    case eStyleStruct_Position:      	printf("eStyleStruct_Position       "); sizeOfStruct = sizeof(StylePositionImpl);  break;
		    case eStyleStruct_Text:      			printf("eStyleStruct_Text           "); sizeOfStruct = sizeof(StyleTextImpl);  break;
		    case eStyleStruct_Display:      	printf("eStyleStruct_Display        "); sizeOfStruct = sizeof(StyleDisplayImpl);  break;
		    case eStyleStruct_Table:      		printf("eStyleStruct_Table          "); sizeOfStruct = sizeof(StyleTableImpl);  break;
		    case eStyleStruct_Content:      	printf("eStyleStruct_Content        "); sizeOfStruct = sizeof(StyleContentImpl);  break;
		    case eStyleStruct_UserInterface:  printf("eStyleStruct_UserInterface  "); sizeOfStruct = sizeof(StyleUserInterfaceImpl);  break;
		    case eStyleStruct_Print: 					printf("eStyleStruct_Print          "); sizeOfStruct = sizeof(StylePrintImpl);  break;
		    case eStyleStruct_Margin: 				printf("eStyleStruct_Margin         "); sizeOfStruct = sizeof(StyleMarginImpl);  break;
		    case eStyleStruct_Padding: 				printf("eStyleStruct_Padding        "); sizeOfStruct = sizeof(StylePaddingImpl);  break;
		    case eStyleStruct_Border: 				printf("eStyleStruct_Border         "); sizeOfStruct = sizeof(StyleBorderImpl);  break;
		    case eStyleStruct_Outline: 				printf("eStyleStruct_Outline        "); sizeOfStruct = sizeof(StyleOutlineImpl);  break;
#ifdef INCLUDE_XUL
        case eStyleStruct_XUL:            printf("eStyleStruct_XUL            "); sizeOfStruct = sizeof(StyleXULImpl); break;      
#endif
      }
		  short percentDefault = (totalCount == 0 ? 0 : ((100 * defaultStruct[i]) / totalCount));
	    short percentFromParent = (defaultStruct[i] == 0 ? 0 : ((100 * setFromParent[i]) / defaultStruct[i]));

			footprint = totalCount * sizeOfStruct;
			totalFootprint += footprint;

	    potentialGain = defaultStruct[i] * sizeOfStruct;
	    totalPotentialGain += potentialGain;

	    printf("   %7ld        %3d             %3d             %5d             %5d\n", defaultStruct[i], percentDefault, percentFromParent, sizeOfStruct, potentialGain / 1024);
    }
    printf("-------------------------------------------------------------------------------------------------------------\n");
    printf("Current footprint: %4ld Kb\n", totalFootprint / 1024);
    printf("Potential gain:    %4ld Kb (or %d%c)\n", totalPotentialGain / 1024, totalPotentialGain*100/totalFootprint, '%');
    printf("Would remain:      %4ld Kb\n", (totalFootprint - totalPotentialGain) / 1024);
    printf("-------------------------------------------------------------------------------------------------------------\n");
    printf("These stats come from the nsStyleContextData structures that have been deleted since the last output.\n");
    printf("To get the stats for a particular page: load page, dump stats, load 'about:blank', dump stats again.\n");
    printf("-------------------------------------------------------------------------------------------------------------\n");
    printf("\n\n\n");
  }

	if (resetCounters) {
		resetCounters = false;
		totalCount = 0;
		for (short i = 0; i < max_structs; i ++) {
		  defaultStruct[i] = 0L;
		  setFromParent[i] = 0L;
		}
	}

  if (!aStyleContextData) {
    printf ("*** aStyleContextData is nil\n");
    return;
  }
 
	totalCount++;
  for (short i = 0; i < max_structs; i ++) {
    short index = i+1;
    switch (index) {
		  case eStyleStruct_Font:
		    if (aStyleContextData->mFont.CalcDifference(aStyleContextData->mFont.mInternalFont) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mFont.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Color:
		    if (aStyleContextData->mColor.CalcDifference(aStyleContextData->mColor.mInternalColor) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mColor.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_List:
		    if (aStyleContextData->mList.CalcDifference(aStyleContextData->mList.mInternalList) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mList.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Position:
		    if (aStyleContextData->mPosition.CalcDifference(aStyleContextData->mPosition.mInternalPosition) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mPosition.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Text:
		    if (aStyleContextData->mText.CalcDifference(aStyleContextData->mText.mInternalText) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mText.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Display:
		    if (aStyleContextData->mDisplay.CalcDifference(aStyleContextData->mDisplay.mInternalDisplay) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mDisplay.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Table:
		    if (aStyleContextData->mTable.CalcDifference(aStyleContextData->mTable.mInternalTable) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mTable.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Content:
		    if (aStyleContextData->mContent.CalcDifference(aStyleContextData->mContent.mInternalContent) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mContent.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_UserInterface:
		    if (aStyleContextData->mUserInterface.CalcDifference(aStyleContextData->mUserInterface.mInternalUserInterface) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mUserInterface.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Print:
		    if (aStyleContextData->mPrint.CalcDifference(aStyleContextData->mPrint.mInternalPrint) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mPrint.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Margin:
		    if (aStyleContextData->mMargin.CalcDifference(aStyleContextData->mMargin.mInternalMargin) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mMargin.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Padding:
		    if (aStyleContextData->mPadding.CalcDifference(aStyleContextData->mPadding.mInternalPadding) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mPadding.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Border:
		    if (aStyleContextData->mBorder.CalcDifference(aStyleContextData->mBorder.mInternalBorder) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mBorder.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
		  case eStyleStruct_Outline:
		    if (aStyleContextData->mOutline.CalcDifference(aStyleContextData->mOutline.mInternalOutline) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mOutline.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
#ifdef INCLUDE_XUL
      case eStyleStruct_XUL:
		    if (aStyleContextData->mXUL.CalcDifference(aStyleContextData->mXUL.mInternalXUL) == NS_STYLE_HINT_NONE) {
		    	defaultStruct[i]++;
			    if (aStyleContextData->mXUL.mSetFromParent)
			    	setFromParent[i]++;
		    }
		    break;
#endif
    }
  }

  static short inCount = 0;
  static short outCount = 0;
  if (inCount++ % 1000 == 0) {
    switch (outCount++) {
      case 0:  printf("still logging"); 		 break;
      case 20: printf("\n"); outCount = 0;	 break;
      default: printf(".");  fflush(stdout); break;
    }
  }
}
#endif // LOG_STYLE_STRUCTS

//=========================================================================================================

nsStyleContextData::~nsStyleContextData(void)
{
  NS_ASSERTION(0 == mRefCnt, "RefCount error in ~nsStyleContextData");
  // debug here...
#ifdef LOG_STYLE_STRUCTS
  LogStyleStructs(this);
#endif
}

PRUint32 nsStyleContextData::ComputeCRC32(PRUint32 aCrc) const
{
  PRUint32 crc = aCrc;

#ifdef COMPUTE_STYLEDATA_CRC
  // have each style struct compute its own CRC, propogating the previous value...
  crc = mFont.ComputeCRC32(crc);
  crc = mColor.ComputeCRC32(crc);
  crc = mList.ComputeCRC32(crc);
  crc = mPosition.ComputeCRC32(crc);
  crc = mText.ComputeCRC32(crc);
  crc = mDisplay.ComputeCRC32(crc);
  crc = mTable.ComputeCRC32(crc);
  crc = mContent.ComputeCRC32(crc);
  crc = mUserInterface.ComputeCRC32(crc);
	crc = mPrint.ComputeCRC32(crc);
	crc = mMargin.ComputeCRC32(crc);
	crc = mPadding.ComputeCRC32(crc);
	crc = mBorder.ComputeCRC32(crc);
	crc = mOutline.ComputeCRC32(crc);
#ifdef INCLUDE_XUL
  crc = mXUL.ComputeCRC32(crc);
#endif
#else
  crc = 0;
#endif

  return crc;
}

void nsStyleContextData::SizeOf(nsISizeOfHandler *aSizeOfHandler, PRUint32 &aSize)
{
  NS_ASSERTION(aSizeOfHandler, "SizeOfHandler cannot be null in SizeOf");

  // first get the unique items collection
  UNIQUE_STYLE_ITEMS(uniqueItems);

  if(! uniqueItems->AddItem((void*)this) ){
    // object has already been accounted for
    return;
  }
  // get or create a tag for this instance
  nsCOMPtr<nsIAtom> tag;
  tag = getter_AddRefs(NS_NewAtom("StyleContextData"));
  // get the size of an empty instance and add to the sizeof handler
  aSize = sizeof(*this);
  aSizeOfHandler->AddSize(tag,aSize);
}

#endif //#ifdef SHARE_STYLECONTEXTS

//----------------------------------------------------------------------

class StyleContextImpl : public nsIStyleContext,
                         protected nsIMutableStyleContext { // you can't QI to nsIMutableStyleContext
public:
  StyleContextImpl(nsIStyleContext* aParent, nsIAtom* aPseudoTag, 
                   nsISupportsArray* aRules, 
                   nsIPresContext* aPresContext);
  virtual ~StyleContextImpl();

  NS_DECL_AND_IMPL_ZEROING_OPERATOR_NEW

  NS_DECL_ISUPPORTS

  virtual nsIStyleContext*  GetParent(void) const;
  virtual nsISupportsArray* GetStyleRules(void) const;
  virtual PRInt32 GetStyleRuleCount(void) const;
  NS_IMETHOD GetPseudoType(nsIAtom*& aPseudoTag) const;

  NS_IMETHOD FindChildWithRules(const nsIAtom* aPseudoTag, nsISupportsArray* aRules,
                                nsIStyleContext*& aResult);

  virtual PRBool    Equals(const nsIStyleContext* aOther) const;
  virtual PRUint32  HashValue(void) const;

  NS_IMETHOD RemapStyle(nsIPresContext* aPresContext, PRBool aRecurse = PR_TRUE);

  NS_IMETHOD GetStyle(nsStyleStructID aSID, nsStyleStruct& aStruct) const;
  NS_IMETHOD SetStyle(nsStyleStructID aSID, const nsStyleStruct& aStruct);

  virtual const nsStyleStruct* GetStyleData(nsStyleStructID aSID);
  virtual nsStyleStruct* GetMutableStyleData(nsStyleStructID aSID);

  virtual void ForceUnique(void);
  virtual void RecalcAutomaticData(nsIPresContext* aPresContext);
  virtual void CalcBorderPaddingFor(const nsIFrame* aFrame, nsMargin& aBorderPadding) const;
  NS_IMETHOD  CalcStyleDifference(nsIStyleContext* aOther, PRInt32& aHint,PRBool aStopAtFirstDifference = PR_FALSE) const;

#ifdef SHARE_STYLECONTEXTS
  // evaluate and execute the style data sharing
  // - if nothing to share, it leaves the current style data intact,
  //   otherwise it calls ShareStyleDataFrom to share another context's data
  //   and releases the old data
  nsresult ShareStyleData(void);

  // share the style data of the StyleDataDonor
  // NOTE: the donor instance is cast to a StyleContextImpl to keep the
  //       interface free of implementation types. This may be invalid in 
  //       the future
  // XXX - reconfigure APIs to avoid casting the interface to the impl
  nsresult ShareStyleDataFrom(nsIStyleContext*aStyleDataDonor);
  
  // sets aMatches to PR_TRUE if the style data of aStyleContextToMatch matches the 
  // style data of this, PR_FALSE otherwise
  NS_IMETHOD StyleDataMatches(nsIStyleContext* aStyleContextToMatch, PRBool *aMatches);

  // get the key for this context (CRC32 value)
  NS_IMETHOD GetStyleContextKey(scKey &aKey) const;

  // update the style set cache by adding this context to it
  // - NOTE: mStyleSet member must be set
  nsresult UpdateStyleSetCache( void ) const;
#endif

  virtual void  List(FILE* out, PRInt32 aIndent);

  virtual void SizeOf(nsISizeOfHandler *aSizeOfHandler, PRUint32 &aSize);

#ifdef DEBUG
  virtual void DumpRegressionData(nsIPresContext* aPresContext, FILE* out, PRInt32 aIndent);
#endif

protected:
  void AppendChild(StyleContextImpl* aChild);
  void RemoveChild(StyleContextImpl* aChild);

  StyleContextImpl* mParent;
  StyleContextImpl* mChild;
  StyleContextImpl* mEmptyChild;
  StyleContextImpl* mPrevSibling;
  StyleContextImpl* mNextSibling;

  nsIAtom*          mPseudoTag;

  PRUint32          mRuleHash;
  nsISupportsArray* mRules;
  PRInt16           mDataCode;

#ifdef SHARE_STYLECONTEXTS

  nsStyleContextData*     mStyleData;

#else

  // the style data...
  StyleFontImpl           mFont;
  StyleColorImpl          mColor;
  StyleListImpl           mList;
  StylePositionImpl       mPosition;
  StyleTextImpl           mText;
  StyleDisplayImpl        mDisplay;
  StyleTableImpl          mTable;
  StyleContentImpl        mContent;
  StyleUserInterfaceImpl  mUserInterface;
	StylePrintImpl					mPrint;
	StyleMarginImpl					mMargin;
	StylePaddingImpl				mPadding;
	StyleBorderImpl					mBorder;
	StyleOutlineImpl				mOutline;
#ifdef INCLUDE_XUL
  StyleXULImpl            mXUL;
#endif

#endif // #ifdef SHARE_STYLECONTEXTS

  // make sure we have valid style data
  nsresult EnsureStyleData(nsIPresContext* aPresContext);
  nsresult HaveStyleData(void) const;

  nsCOMPtr<nsIStyleSet>   mStyleSet;
};

static PRInt32 gLastDataCode;

static PRBool HashStyleRule(nsISupports* aRule, void* aData)
{
  *((PRUint32*)aData) ^= PRUint32(aRule);
  return PR_TRUE;
}

#ifdef XP_MAC
#pragma mark -
#endif

StyleContextImpl::StyleContextImpl(nsIStyleContext* aParent,
                                   nsIAtom* aPseudoTag,
                                   nsISupportsArray* aRules, 
                                   nsIPresContext* aPresContext)
  : mParent((StyleContextImpl*)aParent),
    mChild(nsnull),
    mEmptyChild(nsnull),
    mPseudoTag(aPseudoTag),
    mRules(aRules),
    mDataCode(-1),
#ifdef SHARE_STYLECONTEXTS
    mStyleData(nsnull)
#else
    mFont(aPresContext->GetDefaultFontDeprecated(), aPresContext->GetDefaultFixedFontDeprecated()),
    mColor(),
    mSpacing(),
    mList(),
    mPosition(),
    mText(),
    mDisplay(),
    mTable(),
    mContent(),
    mUserInterface(),
#ifdef INCLUDE_XUL
    mXUL(),
#endif
    mPrint()
#endif
{
  NS_INIT_REFCNT();
  NS_IF_ADDREF(mPseudoTag);
  NS_IF_ADDREF(mRules);

  mNextSibling = this;
  mPrevSibling = this;
  if (nsnull != mParent) {
    NS_ADDREF(mParent);
    mParent->AppendChild(this);
  }

  mRuleHash = 0;
  if (nsnull != mRules) {
    mRules->EnumerateForwards(HashStyleRule, &mRuleHash);
  }

#ifdef SHARE_STYLECONTEXTS
  // remember the style set
  nsIPresShell* shell = nsnull;
  aPresContext->GetShell(&shell);
  if (shell) {
    shell->GetStyleSet( getter_AddRefs(mStyleSet) );
    NS_RELEASE( shell );
  }
#endif // SHARE_STYLECONTEXTS
}

StyleContextImpl::~StyleContextImpl()
{
  NS_ASSERTION((nsnull == mChild) && (nsnull == mEmptyChild), "destructing context with children");

  if (mParent) {
    mParent->RemoveChild(this);
    NS_RELEASE(mParent);
  }

  NS_IF_RELEASE(mPseudoTag);
  NS_IF_RELEASE(mRules);

#ifdef SHARE_STYLECONTEXTS
  // remove this instance from the style set (remember, the set does not AddRef or Release us)
  if (mStyleSet) {
    mStyleSet->RemoveStyleContext((nsIStyleContext *)this);
  } else {
    NS_ASSERTION(0, "StyleSet is not optional in a StyleContext's dtor...");
  }
  // release the style data so it can be reclaimed when no longer referenced
  NS_IF_RELEASE(mStyleData);
#endif // SHARE_STYLECONTEXTS
}

NS_IMPL_ADDREF(StyleContextImpl)
NS_IMPL_RELEASE(StyleContextImpl)

NS_IMETHODIMP
StyleContextImpl::QueryInterface(const nsIID& aIID, void** aInstancePtr)
{
  NS_PRECONDITION(nsnull != aInstancePtr, "null pointer");
  if (nsnull == aInstancePtr) {
    return NS_ERROR_NULL_POINTER;
  }
  static NS_DEFINE_IID(kISupportsIID, NS_ISUPPORTS_IID);
  if (aIID.Equals(NS_GET_IID(nsIStyleContext))) {
    *aInstancePtr = (void*)(nsIStyleContext*)this;
    NS_ADDREF_THIS();
    return NS_OK;
  }
  if (aIID.Equals(kISupportsIID)) {
    *aInstancePtr = (void*) (nsISupports*)(nsIStyleContext*)this;
    NS_ADDREF_THIS();
    return NS_OK;
  }
  return NS_NOINTERFACE;
}

nsIStyleContext* StyleContextImpl::GetParent(void) const
{
  NS_IF_ADDREF(mParent);
  return mParent;
}

void StyleContextImpl::AppendChild(StyleContextImpl* aChild)
{
  if (0 == aChild->GetStyleRuleCount()) {
    if (nsnull == mEmptyChild) {
      mEmptyChild = aChild;
    }
    else {
      aChild->mNextSibling = mEmptyChild;
      aChild->mPrevSibling = mEmptyChild->mPrevSibling;
      mEmptyChild->mPrevSibling->mNextSibling = aChild;
      mEmptyChild->mPrevSibling = aChild;
    }
  }
  else {
    if (nsnull == mChild) {
      mChild = aChild;
    }
    else {
      aChild->mNextSibling = mChild;
      aChild->mPrevSibling = mChild->mPrevSibling;
      mChild->mPrevSibling->mNextSibling = aChild;
      mChild->mPrevSibling = aChild;
    }
  }
}

void StyleContextImpl::RemoveChild(StyleContextImpl* aChild)
{
  NS_ASSERTION((nsnull != aChild) && (this == aChild->mParent), "bad argument");

  if ((nsnull == aChild) || (this != aChild->mParent)) {
    return;
  }

  if (0 == aChild->GetStyleRuleCount()) { // is empty 
    if (aChild->mPrevSibling != aChild) { // has siblings
      if (mEmptyChild == aChild) {
        mEmptyChild = mEmptyChild->mNextSibling;
      }
    } 
    else {
      NS_ASSERTION(mEmptyChild == aChild, "bad sibling pointers");
      mEmptyChild = nsnull;
    }
  }
  else {  // isn't empty
    if (aChild->mPrevSibling != aChild) { // has siblings
      if (mChild == aChild) {
        mChild = mChild->mNextSibling;
      }
    }
    else {
      NS_ASSERTION(mChild == aChild, "bad sibling pointers");
      if (mChild == aChild) {
        mChild = nsnull;
      }
    }
  }
  aChild->mPrevSibling->mNextSibling = aChild->mNextSibling;
  aChild->mNextSibling->mPrevSibling = aChild->mPrevSibling;
  aChild->mNextSibling = aChild;
  aChild->mPrevSibling = aChild;
}

nsISupportsArray* StyleContextImpl::GetStyleRules(void) const
{
  nsISupportsArray* result = mRules;
  NS_IF_ADDREF(result);
  return result;
}

PRInt32 StyleContextImpl::GetStyleRuleCount(void) const
{
  if (nsnull != mRules) {
    PRUint32 cnt;
    nsresult rv = mRules->Count(&cnt);
    if (NS_FAILED(rv)) return 0;        // XXX error?
    return cnt;
  }
  return 0;
}

NS_IMETHODIMP
StyleContextImpl::GetPseudoType(nsIAtom*& aPseudoTag) const
{
  aPseudoTag = mPseudoTag;
  NS_IF_ADDREF(aPseudoTag);
  return NS_OK;
}

NS_IMETHODIMP
StyleContextImpl::FindChildWithRules(const nsIAtom* aPseudoTag, 
                                     nsISupportsArray* aRules,
                                     nsIStyleContext*& aResult)
{
  aResult = nsnull;

  if ((nsnull != mChild) || (nsnull != mEmptyChild)) {
    StyleContextImpl* child;
    PRInt32 ruleCount;
    if (aRules) {
      PRUint32 cnt;
      nsresult rv = aRules->Count(&cnt);
      if (NS_FAILED(rv)) return rv;
      ruleCount = cnt;
    }
    else
      ruleCount = 0;
    if (0 == ruleCount) {
      if (nsnull != mEmptyChild) {
        child = mEmptyChild;
        do {
          if ((0 == child->mDataCode) &&  // only look at children with un-twiddled data
              (aPseudoTag == child->mPseudoTag)) {
            aResult = child;
            break;
          }
          child = child->mNextSibling;
        } while (child != mEmptyChild);
      }
    }
    else if (nsnull != mChild) {
      PRUint32 hash = 0;
      aRules->EnumerateForwards(HashStyleRule, &hash);
      child = mChild;
      do {
        PRUint32 cnt;
        if ((0 == child->mDataCode) &&  // only look at children with un-twiddled data
            (child->mRuleHash == hash) &&
            (child->mPseudoTag == aPseudoTag) &&
            (nsnull != child->mRules) &&
            NS_SUCCEEDED(child->mRules->Count(&cnt)) && 
            (PRInt32)cnt == ruleCount) {
          if (child->mRules->Equals(aRules)) {
            aResult = child;
            break;
          }
        }
        child = child->mNextSibling;
      } while (child != mChild);
    }
  }
  NS_IF_ADDREF(aResult);
  return NS_OK;
}


PRBool StyleContextImpl::Equals(const nsIStyleContext* aOther) const
{
  PRBool  result = PR_TRUE;
  const StyleContextImpl* other = (StyleContextImpl*)aOther;

  if (other != this) {
    if (mParent != other->mParent) {
      result = PR_FALSE;
    }
    else if (mDataCode != other->mDataCode) {
      result = PR_FALSE;
    }
    else if (mPseudoTag != other->mPseudoTag) {
      result = PR_FALSE;
    }
    else {
      if ((nsnull != mRules) && (nsnull != other->mRules)) {
        if (mRuleHash == other->mRuleHash) {
          result = mRules->Equals(other->mRules);
        }
        else {
          result = PR_FALSE;
        }
      }
      else {
        result = PRBool((nsnull == mRules) && (nsnull == other->mRules));
      }
    }
  }
  return result;
}

PRUint32 StyleContextImpl::HashValue(void) const
{
  return mRuleHash;
}

//=========================================================================================================
#ifdef DEBUG
// define this to get statistics on the number of calls
// to GetStyleData() and their depth in the Style tree.
//#define LOG_GET_STYLE_DATA_CALLS  //XXX pierre
#endif

#ifdef LOG_GET_STYLE_DATA_CALLS

#ifdef XP_MAC
#include <Events.h>
#include <Timer.h>
static bool MacKeyDown(unsigned char theKey)
{
	KeyMap map;
	GetKeys(map);
	return ((*((unsigned char *)map + (theKey >> 3)) >> (theKey & 7)) & 1) != 0;
}
#endif


static bool IsTimeToDumpGetStyleDataCalls()
{
  bool timeToDump = false;
#ifdef XP_MAC
	static unsigned long lastTicks = 0;
  if (MacKeyDown(0x3b)) { // control key
    if ((unsigned long)(::TickCount() - lastTicks) > 60) {
	    lastTicks = ::TickCount();
	    timeToDump = true;
	  }
	}
#endif
  return timeToDump;
}

enum LogCallType {
  logCallType_GetStyleData = 0,
  logCallType_GetMutableStyleData,
  logCallType_GetStyle,

  logCallType_Max
};

static void LogGetStyleDataCall(nsStyleStructID aSID, LogCallType aLogCallType, nsIStyleContext* aStyleContext, bool aEnteringFunction)
{
#define max_structs (eStyleStruct_Max + 1)
#define small_depth_threshold	8

  static unsigned long calls[max_structs*logCallType_Max];
  static unsigned long callspercent[max_structs*logCallType_Max];
  static unsigned long depth[max_structs*logCallType_Max];
  static unsigned long maxdepth[max_structs*logCallType_Max];
  static unsigned long smalldepth[max_structs*logCallType_Max];
  static unsigned long microsecs[logCallType_Max];
  static unsigned long totalMicrosecs;
  static UnsignedWide  startMicrosecs;
  static UnsignedWide  endMicrosecs;

  if (!aEnteringFunction) {
    ::Microseconds(&endMicrosecs);
    totalMicrosecs += endMicrosecs.lo - startMicrosecs.lo;
    microsecs[aLogCallType] += endMicrosecs.lo - startMicrosecs.lo;
    return;
  }


	static bool resetCounters = true;

  if (IsTimeToDumpGetStyleDataCalls()) {
    resetCounters = true;
    
    unsigned long totalCalls;
    unsigned long totalMaxdepth;
    unsigned long totalDepth;
    for (short i = 0; i < (max_structs*logCallType_Max); i ++) {

			if (i%max_structs == 0) {
	    	switch (i/max_structs) {
	    	  case 0:
	    	    printf("\n\n\n");
	    	    printf("----GetStyleData--------------------------------------------------------------------------\n");
	    	    printf("                                calls   calls%c        max depth     avg depth   (depth<%d)%\n", '%', small_depth_threshold);
	    	    break;
	    	  case 1:
	    	    printf("----GetMutableStyleData-------------------------------------------------------------------\n");
	    	    printf("                                calls   calls%c        max depth     avg depth   (depth<%d)%\n", '%', small_depth_threshold);
	    	    break;
	    	  case 2:
	    	    printf("----GetStyle------------------------------------------------------------------------------\n");
	    	    printf("                                calls   calls%c        max depth     avg depth   (depth<%d)%\n", '%', small_depth_threshold);
	    	    break;
	    	}

				totalCalls = totalMaxdepth = totalDepth = 0;
	      for (short j = i; j < i + max_structs; j++) {
					totalCalls += calls[j];
					totalDepth += depth[j];
					if (totalMaxdepth < maxdepth[j]) {
					  totalMaxdepth = maxdepth[j];
					}
	      }
			}

      switch (i%max_structs + 1) {
		    case eStyleStruct_Font:      			printf("eStyleStruct_Font           "); break;
		    case eStyleStruct_Color:      		printf("eStyleStruct_Color          "); break;
		    case eStyleStruct_List:      			printf("eStyleStruct_List           "); break;
		    case eStyleStruct_Position:      	printf("eStyleStruct_Position       "); break;
		    case eStyleStruct_Text:      			printf("eStyleStruct_Text           "); break;
		    case eStyleStruct_Display:      	printf("eStyleStruct_Display        "); break;
		    case eStyleStruct_Table:      		printf("eStyleStruct_Table          "); break;
		    case eStyleStruct_Content:      	printf("eStyleStruct_Content        "); break;
		    case eStyleStruct_UserInterface:  printf("eStyleStruct_UserInterface  "); break;
		    case eStyleStruct_Print: 					printf("eStyleStruct_Print          "); break;
		    case eStyleStruct_Margin: 				printf("eStyleStruct_Margin         "); break;
		    case eStyleStruct_Padding: 				printf("eStyleStruct_Padding        "); break;
		    case eStyleStruct_Border: 				printf("eStyleStruct_Border         "); break;
		    case eStyleStruct_Outline: 				printf("eStyleStruct_Outline        "); break;
		    case eStyleStruct_BorderPaddingShortcut: 				printf("BorderPaddingShortcut       "); break;
#ifdef INCLUDE_XUL
        case eStyleStruct_XUL:            printf("eStyleStruct_XUL            "); break;
#endif
      }
			short percent = 100*calls[i]/totalCalls;
			short avdepth = calls[i] == 0 ? 0 : round(float(depth[i])/float(calls[i]));
			short smdepth = 100*smalldepth[i]/calls[i];
			if (percent == 0) {
	      printf("  %7ld      -             %3ld          %3d         %3d\n", calls[i], maxdepth[i], avdepth, smdepth);
			}
			else {
	      printf("  %7ld     %2ld             %3ld          %3d         %3d\n", calls[i], percent, maxdepth[i], avdepth, smdepth);
			}

      if (i%max_structs + 1 == max_structs) {
			  short totaldepth = totalCalls == 0 ? 0 : round(float(totalDepth)/float(totalCalls));
		    printf("TOTAL                       ");
	      printf("  %7ld    100             %3ld          %3d    %ld ms\n", totalCalls, totalMaxdepth, totaldepth, microsecs[i/max_structs]/1000);
      }

    }
    printf("------------------------------------------------------------------------------------------\n");
    printf("TOTAL time = %ld microsecs (= %ld ms)\n", totalMicrosecs, totalMicrosecs/1000);
    printf("------------------------------------------------------------------------------------------\n\n\n");
  }

	if (resetCounters) {
		resetCounters = false;
		totalMicrosecs = 0;
		for (short i = 0; i < logCallType_Max; i ++) {
		  microsecs[i] = 0L;
		}
		for (short i = 0; i < (max_structs*logCallType_Max); i ++) {
		  calls[i] = 0L;
		  depth[i] = 0L;
		  maxdepth[i] = 0L;
		  smalldepth[i] = 0L;
		}
	}

  short index = aSID - 1;
  index += max_structs * aLogCallType;

  calls[index]++;

  unsigned long curdepth = 0;
  nsCOMPtr<nsIStyleContext> childContext;
  nsCOMPtr<nsIStyleContext> parentContext;
  childContext  = aStyleContext;
  parentContext = getter_AddRefs(childContext->GetParent());
  while (parentContext != nsnull) {
    curdepth++;
    parentContext = getter_AddRefs(childContext->GetParent());
    if (parentContext == childContext) {
      break;
    }
    childContext = parentContext;
  }
	depth[index] += curdepth;
  if (maxdepth[index] < curdepth) {
    maxdepth[index] = curdepth;
  }
  if (curdepth <= small_depth_threshold) {
  	smalldepth[index]++;
  }

  static short inCount = 0;
  static short outCount = 0;
  if (inCount++ % 1000 == 0) {
    switch (outCount++) {
      case 0:  printf("still logging"); 		 break;
      case 20: printf("\n"); outCount = 0;	 break;
      default: printf(".");  fflush(stdout); break;
    }
  }
  ::Microseconds(&startMicrosecs);
}
#endif // LOG_GET_STYLE_DATA_CALLS
//=========================================================================================================

const nsStyleStruct* StyleContextImpl::GetStyleData(nsStyleStructID aSID)
{
#ifdef LOG_GET_STYLE_DATA_CALLS
  LogGetStyleDataCall(aSID, logCallType_GetStyleData, this, true);
#endif

  nsStyleStruct*  result = nsnull;

  switch (aSID) {
    case eStyleStruct_Font:
      result = & GETSCDATA(Font);
      break;
    case eStyleStruct_Color:
      result = & GETSCDATA(Color);
      break;
    case eStyleStruct_List:
      result = & GETSCDATA(List);
      break;
    case eStyleStruct_Position:
      result = & GETSCDATA(Position);
      break;
    case eStyleStruct_Text:
      result = & GETSCDATA(Text);
      break;
    case eStyleStruct_Display:
      result = & GETSCDATA(Display);
      break;
    case eStyleStruct_Table:
      result = & GETSCDATA(Table);
      break;
    case eStyleStruct_Content:
      result = & GETSCDATA(Content);
      break;
    case eStyleStruct_UserInterface:
      result = & GETSCDATA(UserInterface);
      break;
    case eStyleStruct_Print:
    	result = & GETSCDATA(Print);
    	break;
    case eStyleStruct_Margin:
    	result = & GETSCDATA(Margin);
    	break;
    case eStyleStruct_Padding:
    	result = & GETSCDATA(Padding);
    	break;
    case eStyleStruct_Border:
    	result = & GETSCDATA(Border);
    	break;
    case eStyleStruct_Outline:
    	result = & GETSCDATA(Outline);
    	break;
#ifdef INCLUDE_XUL
    case eStyleStruct_XUL:
    	result = & GETSCDATA(XUL);
    	break;
#endif
    default:
      NS_ERROR("Invalid style struct id");
      break;
  }
#ifdef LOG_GET_STYLE_DATA_CALLS
  LogGetStyleDataCall(aSID, logCallType_GetStyleData, this, false);
#endif

  return result;
}

nsStyleStruct* StyleContextImpl::GetMutableStyleData(nsStyleStructID aSID)
{
#ifdef LOG_GET_STYLE_DATA_CALLS
  LogGetStyleDataCall(aSID, logCallType_GetMutableStyleData, this, true);
#endif

  nsStyleStruct*  result = nsnull;

    switch (aSID) {
    case eStyleStruct_Font:
      result = & GETSCDATA(Font);
      break;
    case eStyleStruct_Color:
      result = & GETSCDATA(Color);
      break;
    case eStyleStruct_List:
      result = & GETSCDATA(List);
      break;
    case eStyleStruct_Position:
      result = & GETSCDATA(Position);
      break;
    case eStyleStruct_Text:
      result = & GETSCDATA(Text);
      break;
    case eStyleStruct_Display:
      result = & GETSCDATA(Display);
      break;
    case eStyleStruct_Table:
      result = & GETSCDATA(Table);
      break;
    case eStyleStruct_Content:
      result = & GETSCDATA(Content);
      break;
    case eStyleStruct_UserInterface:
      result = & GETSCDATA(UserInterface);
      break;
    case eStyleStruct_Print:
    	result = & GETSCDATA(Print);
    	break;
    case eStyleStruct_Margin:
    	result = & GETSCDATA(Margin);
    	break;
    case eStyleStruct_Padding:
    	result = & GETSCDATA(Padding);
    	break;
    case eStyleStruct_Border:
    	result = & GETSCDATA(Border);
    	break;
    case eStyleStruct_Outline:
    	result = & GETSCDATA(Outline);
    	break;
#ifdef INCLUDE_XUL
    case eStyleStruct_XUL:
    	result = & GETSCDATA(XUL);
    	break;
#endif
    default:
      NS_ERROR("Invalid style struct id");
      break;
  }

  if (nsnull != result) {
    if (0 == mDataCode) {
//      mDataCode = ++gLastDataCode;  // XXX temp disable, this is still used but not needed to force unique
    }
  }
#ifdef LOG_GET_STYLE_DATA_CALLS
  LogGetStyleDataCall(aSID, logCallType_GetMutableStyleData, this, false);
#endif

  return result;
}

void StyleContextImpl::CalcBorderPaddingFor(const nsIFrame* aFrame, nsMargin& aBorderPadding) const
{
  nsMargin border, padding;
  if (!GETSCDATA(Border).GetBorder(border)) {
    GETSCDATA(Border).CalcBorderFor(aFrame, border);
  }
  if (!GETSCDATA(Padding).GetPadding(padding)) {
    GETSCDATA(Padding).CalcPaddingFor(aFrame, padding);
  }
  aBorderPadding = border + padding;
}

NS_IMETHODIMP
StyleContextImpl::GetStyle(nsStyleStructID aSID, nsStyleStruct& aStruct) const
{
#ifdef LOG_GET_STYLE_DATA_CALLS
  LogGetStyleDataCall(aSID, logCallType_GetStyle, (nsIStyleContext*)this, true);
#endif

  nsresult result = NS_OK;
  switch (aSID) {
    case eStyleStruct_Font:
      GETSCDATA(Font).CopyTo((nsStyleFont&)aStruct);
      break;
    case eStyleStruct_Color:
      GETSCDATA(Color).CopyTo((nsStyleColor&)aStruct);
      break;
    case eStyleStruct_List:
      GETSCDATA(List).CopyTo((nsStyleList&)aStruct);
      break;
    case eStyleStruct_Position:
      GETSCDATA(Position).CopyTo((nsStylePosition&)aStruct);
      break;
    case eStyleStruct_Text:
      GETSCDATA(Text).CopyTo((nsStyleText&)aStruct);
      break;
    case eStyleStruct_Display:
      GETSCDATA(Display).CopyTo((nsStyleDisplay&)aStruct);
      break;
    case eStyleStruct_Table:
      GETSCDATA(Table).CopyTo((nsStyleTable&)aStruct);
      break;
    case eStyleStruct_Content:
      GETSCDATA(Content).CopyTo((nsStyleContent&)aStruct);
      break;
    case eStyleStruct_UserInterface:
      GETSCDATA(UserInterface).CopyTo((nsStyleUserInterface&)aStruct);
      break;
    case eStyleStruct_Print:
      GETSCDATA(Print).CopyTo((nsStylePrint&)aStruct);
    	break;
    case eStyleStruct_Margin:
      GETSCDATA(Margin).CopyTo((nsStyleMargin&)aStruct);
    	break;
    case eStyleStruct_Padding:
      GETSCDATA(Padding).CopyTo((nsStylePadding&)aStruct);
    	break;
    case eStyleStruct_Border:
      GETSCDATA(Border).CopyTo((nsStyleBorder&)aStruct);
    	break;
    case eStyleStruct_Outline:
      GETSCDATA(Outline).CopyTo((nsStyleOutline&)aStruct);
    	break;
#ifdef INCLUDE_XUL
    case eStyleStruct_XUL:
      GETSCDATA(XUL).CopyTo((nsStyleXUL&)aStruct);
    	break;
#endif
    case eStyleStruct_BorderPaddingShortcut: {
      nsMargin border, padding;
      if (GETSCDATA(Border).GetBorder(border)) {
	      if (GETSCDATA(Padding).GetPadding(padding)) {
	        border += padding;
	        ((nsStyleBorderPadding&)aStruct).SetBorderPadding(border);
	      }
      }
      break;
    }
    default:
      NS_ERROR("Invalid style struct id");
      result = NS_ERROR_INVALID_ARG;
      break;
  }
#ifdef LOG_GET_STYLE_DATA_CALLS
  LogGetStyleDataCall(aSID, logCallType_GetStyle, (nsIStyleContext*)this, false);
#endif

  return result;
}

NS_IMETHODIMP
StyleContextImpl::SetStyle(nsStyleStructID aSID, const nsStyleStruct& aStruct)
{
  nsresult result = NS_OK;
  switch (aSID) {
    case eStyleStruct_Font:
      GETSCDATA(Font).SetFrom((const nsStyleFont&)aStruct);
      break;
    case eStyleStruct_Color:
      GETSCDATA(Color).SetFrom((const nsStyleColor&)aStruct);
      break;
    case eStyleStruct_List:
      GETSCDATA(List).SetFrom((const nsStyleList&)aStruct);
      break;
    case eStyleStruct_Position:
      GETSCDATA(Position).SetFrom((const nsStylePosition&)aStruct);
      break;
    case eStyleStruct_Text:
      GETSCDATA(Text).SetFrom((const nsStyleText&)aStruct);
      break;
    case eStyleStruct_Display:
      GETSCDATA(Display).SetFrom((const nsStyleDisplay&)aStruct);
      break;
    case eStyleStruct_Table:
      GETSCDATA(Table).SetFrom((const nsStyleTable&)aStruct);
      break;
    case eStyleStruct_Content:
      GETSCDATA(Content).SetFrom((const nsStyleContent&)aStruct);
      break;
    case eStyleStruct_UserInterface:
      GETSCDATA(UserInterface).SetFrom((const nsStyleUserInterface&)aStruct);
      break;
    case eStyleStruct_Print:
      GETSCDATA(Print).SetFrom((const nsStylePrint&)aStruct);
    	break;
    case eStyleStruct_Margin:
      GETSCDATA(Margin).SetFrom((const nsStyleMargin&)aStruct);
    	break;
    case eStyleStruct_Padding:
      GETSCDATA(Padding).SetFrom((const nsStylePadding&)aStruct);
   	break;
    case eStyleStruct_Border:
      GETSCDATA(Border).SetFrom((const nsStyleBorder&)aStruct);
    	break;
    case eStyleStruct_Outline:
      GETSCDATA(Outline).SetFrom((const nsStyleOutline&)aStruct);
    	break;
#ifdef INCLUDE_XUL
    case eStyleStruct_XUL:
      GETSCDATA(XUL).SetFrom((const nsStyleXUL&)aStruct);
    	break;
#endif
    default:
      NS_ERROR("Invalid style struct id");
      result = NS_ERROR_INVALID_ARG;
      break;
  }
  return result;
}



struct MapStyleData {
  MapStyleData(nsIMutableStyleContext* aStyleContext, nsIPresContext* aPresContext)
  {
    mStyleContext = aStyleContext;
    mPresContext = aPresContext;
  }
  nsIMutableStyleContext*  mStyleContext;
  nsIPresContext*   mPresContext;
};

static PRBool MapStyleRuleFont(nsISupports* aRule, void* aData)
{
  nsIStyleRule* rule = (nsIStyleRule*)aRule;
  MapStyleData* data = (MapStyleData*)aData;
  rule->MapFontStyleInto(data->mStyleContext, data->mPresContext);
  return PR_TRUE;
}

static PRBool MapStyleRule(nsISupports* aRule, void* aData)
{
  nsIStyleRule* rule = (nsIStyleRule*)aRule;
  MapStyleData* data = (MapStyleData*)aData;
  rule->MapStyleInto(data->mStyleContext, data->mPresContext);
  return PR_TRUE;
}

NS_IMETHODIMP
StyleContextImpl::RemapStyle(nsIPresContext* aPresContext, PRBool aRecurse)
{
  mDataCode = -1;

  if (NS_FAILED(EnsureStyleData(aPresContext))) {
    return NS_ERROR_UNEXPECTED;
  }

  if (nsnull != mParent) {
    GETSCDATA(Font).ResetFrom(&(mParent->GETSCDATA(Font)), aPresContext);
    GETSCDATA(Color).ResetFrom(&(mParent->GETSCDATA(Color)), aPresContext);
    GETSCDATA(List).ResetFrom(&(mParent->GETSCDATA(List)), aPresContext);
    GETSCDATA(Position).ResetFrom(&(mParent->GETSCDATA(Position)), aPresContext);
    GETSCDATA(Text).ResetFrom(&(mParent->GETSCDATA(Text)), aPresContext);
    GETSCDATA(Display).ResetFrom(&(mParent->GETSCDATA(Display)), aPresContext);
    GETSCDATA(Table).ResetFrom(&(mParent->GETSCDATA(Table)), aPresContext);
    GETSCDATA(Content).ResetFrom(&(mParent->GETSCDATA(Content)), aPresContext);
    GETSCDATA(UserInterface).ResetFrom(&(mParent->GETSCDATA(UserInterface)), aPresContext);
    GETSCDATA(Print).ResetFrom(&(mParent->GETSCDATA(Print)), aPresContext);
    GETSCDATA(Margin).ResetFrom(&(mParent->GETSCDATA(Margin)), aPresContext);
    GETSCDATA(Padding).ResetFrom(&(mParent->GETSCDATA(Padding)), aPresContext);
    GETSCDATA(Border).ResetFrom(&(mParent->GETSCDATA(Border)), aPresContext);
    GETSCDATA(Outline).ResetFrom(&(mParent->GETSCDATA(Outline)), aPresContext);
#ifdef INCLUDE_XUL
    GETSCDATA(XUL).ResetFrom(&(mParent->GETSCDATA(XUL)), aPresContext);
#endif
  }
  else {
    GETSCDATA(Font).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Color).ResetFrom(nsnull, aPresContext);
    GETSCDATA(List).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Position).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Text).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Display).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Table).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Content).ResetFrom(nsnull, aPresContext);
    GETSCDATA(UserInterface).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Print).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Margin).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Padding).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Border).ResetFrom(nsnull, aPresContext);
    GETSCDATA(Outline).ResetFrom(nsnull, aPresContext);
#ifdef INCLUDE_XUL
    GETSCDATA(XUL).ResetFrom(nsnull, aPresContext);
#endif
  }

  PRUint32 cnt = 0;
  if (mRules) {
    nsresult rv = mRules->Count(&cnt);
    NS_ASSERTION(NS_SUCCEEDED(rv), "Count failed");
  }
  if (0 < cnt) {
    MapStyleData  data(this, aPresContext);
    mRules->EnumerateForwards(MapStyleRuleFont, &data);
    if (GETSCDATA(Font).mFlags & NS_STYLE_FONT_USE_FIXED) {
      GETSCDATA(Font).mFont = GETSCDATA(Font).mFixedFont;
    }
    mRules->EnumerateForwards(MapStyleRule, &data);
  }
  if (-1 == mDataCode) {
    mDataCode = 0;
  }

  // CSS2 specified fixups:
  //  - these must be done after all declarations are mapped since they can cross style-structs

  // 1) if float is not none, and display is not none, then we must set display to block
  //    XXX - there are problems with following the spec here: what we will do instead of
  //          following the letter of the spec is to make sure that floated elements are
  //          some kind of block, not strictly 'block' - see EnsureBlockDisplay method
  nsStyleDisplay *disp = (nsStyleDisplay *)GetMutableStyleData(eStyleStruct_Display);
  if (disp) {
    if (disp->mDisplay != NS_STYLE_DISPLAY_NONE &&
        disp->mFloats != NS_STYLE_FLOAT_NONE ) {
      EnsureBlockDisplay(disp->mDisplay);
    }
  }
  // 2) if position is 'absolute' or 'fixed' then display must be 'block and float must be 'none'
  //    XXX - see note for fixup 1) above...
  nsStylePosition *pos = (nsStylePosition *)GetStyleData(eStyleStruct_Position);
  if (pos) {
    if (pos->IsAbsolutelyPositioned()) {
      if (disp) {
        if(disp->mDisplay != NS_STYLE_DISPLAY_NONE) {
          EnsureBlockDisplay(disp->mDisplay);
          disp->mFloats = NS_STYLE_FLOAT_NONE;
        }
      }
    }
  }

  nsCompatibility quirkMode = eCompatibility_Standard;
  aPresContext->GetCompatibilityMode(&quirkMode);
  if (eCompatibility_NavQuirks == quirkMode) {
    if (((GETSCDATA(Display).mDisplay == NS_STYLE_DISPLAY_TABLE) || 
         (GETSCDATA(Display).mDisplay == NS_STYLE_DISPLAY_TABLE_CAPTION)) &&
        (nsnull == mPseudoTag)) {

      StyleContextImpl* holdParent = mParent;
      mParent = nsnull; // cut off all inheritance. this really blows

      // XXX the style we do preserve is visibility, direction, language
      PRUint8 visible = GETSCDATA(Display).mVisible;
      PRUint8 direction = GETSCDATA(Display).mDirection;
      nsCOMPtr<nsILanguageAtom> language = GETSCDATA(Display).mLanguage;

      // time to emulate a sub-document
      // This is ugly, but we need to map style once to determine display type
      // then reset and map it again so that all local style is preserved
      if (GETSCDATA(Display).mDisplay != NS_STYLE_DISPLAY_TABLE) {
        GETSCDATA(Font).ResetFrom(nsnull, aPresContext);
      }
      GETSCDATA(Color).ResetFrom(nsnull, aPresContext);
      GETSCDATA(List).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Text).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Position).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Display).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Table).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Content).ResetFrom(nsnull, aPresContext);
      GETSCDATA(UserInterface).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Print).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Margin).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Padding).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Border).ResetFrom(nsnull, aPresContext);
      GETSCDATA(Outline).ResetFrom(nsnull, aPresContext);
#ifdef INCLUDE_XUL
      GETSCDATA(XUL).ResetFrom(nsnull, aPresContext);
#endif
      GETSCDATA(Display).mVisible = visible;
      GETSCDATA(Display).mDirection = direction;
      GETSCDATA(Display).mLanguage = language;

      PRUint32 numRules = 0;
      if (mRules) {
        nsresult rv = mRules->Count(&numRules);
        NS_ASSERTION(NS_SUCCEEDED(rv), "Count failed");
      }
      if (0 < numRules) {
        MapStyleData  data(this, aPresContext);
        mRules->EnumerateForwards(MapStyleRuleFont, &data);
        if (GETSCDATA(Font).mFlags & NS_STYLE_FONT_USE_FIXED) {
          GETSCDATA(Font).mFont = GETSCDATA(Font).mFixedFont;
        }
        mRules->EnumerateForwards(MapStyleRule, &data);
      }
      // reset all font data for tables again
      if (GETSCDATA(Display).mDisplay == NS_STYLE_DISPLAY_TABLE) {
        // get the font-name to reset: this property we preserve
        nsAutoString strName(GETSCDATA(Font).mFont.name);
        nsAutoString strMixedName(GETSCDATA(Font).mFixedFont.name);
   
        GETSCDATA(Font).ResetFrom(nsnull, aPresContext);
   
        // now reset the font names back to original
        GETSCDATA(Font).mFont.name = strName;
        GETSCDATA(Font).mFixedFont.name = strMixedName;
      }
      mParent = holdParent;
    }
  } else {
    // In strict mode, we still have to support one "quirky" thing
    // for tables.  HTML's alignment attributes have always worked
    // so they don't inherit into tables, but instead align the
    // tables.  We should keep doing this, because HTML alignment
    // is just weird, and we shouldn't force it to match CSS.
    if (GETSCDATA(Display).mDisplay == NS_STYLE_DISPLAY_TABLE) {
      // -moz-center and -moz-right are used for HTML's alignment
      if ((GETSCDATA(Text).mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_CENTER) ||
          (GETSCDATA(Text).mTextAlign == NS_STYLE_TEXT_ALIGN_MOZ_RIGHT))
      {
        GETSCDATA(Text).mTextAlign = NS_STYLE_TEXT_ALIGN_DEFAULT;
      }
    }
  }

  RecalcAutomaticData(aPresContext);

#ifdef SHARE_STYLECONTEXTS
  nsresult result = ShareStyleData();
#endif

  if (aRecurse) {
    if (nsnull != mChild) {
      StyleContextImpl* child = mChild;
      do {
        child->RemapStyle(aPresContext);
        child = child->mNextSibling;
      } while (mChild != child);
    }
    if (nsnull != mEmptyChild) {
      StyleContextImpl* child = mEmptyChild;
      do {
        child->RemapStyle(aPresContext);
        child = child->mNextSibling;
      } while (mEmptyChild != child);
    }
  }
  return NS_OK;
}

void StyleContextImpl::ForceUnique(void)
{
  if (mDataCode <= 0) {
    mDataCode = ++gLastDataCode;
  }
}

void StyleContextImpl::RecalcAutomaticData(nsIPresContext* aPresContext)
{
  if (NS_FAILED(EnsureStyleData(aPresContext))) {
    return /*NS_FAILURE*/;
  }
  GETSCDATA(Margin).RecalcData();
  GETSCDATA(Padding).RecalcData();
  GETSCDATA(Border).RecalcData(GETSCDATA(Color).mColor);
  GETSCDATA(Outline).RecalcData();
}

NS_IMETHODIMP
StyleContextImpl::CalcStyleDifference(nsIStyleContext* aOther, PRInt32& aHint,PRBool aStopAtFirstDifference /*= PR_FALSE*/) const
{
  if (NS_FAILED(HaveStyleData())) {
    return NS_ERROR_NULL_POINTER;
  }

  if (aOther) {
    PRInt32 hint;
    const StyleContextImpl* other = (const StyleContextImpl*)aOther;

    aHint = GETSCDATA(Font).CalcDifference(other->GETSCDATA(Font));
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Color).CalcDifference(other->GETSCDATA(Color));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Margin).CalcDifference(other->GETSCDATA(Margin));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Padding).CalcDifference(other->GETSCDATA(Padding));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Border).CalcDifference(other->GETSCDATA(Border));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Outline).CalcDifference(other->GETSCDATA(Outline));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(List).CalcDifference(other->GETSCDATA(List));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Position).CalcDifference(other->GETSCDATA(Position));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Text).CalcDifference(other->GETSCDATA(Text));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Display).CalcDifference(other->GETSCDATA(Display));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Table).CalcDifference(other->GETSCDATA(Table));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Content).CalcDifference(other->GETSCDATA(Content));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(UserInterface).CalcDifference(other->GETSCDATA(UserInterface));
      if (aHint < hint) {
        aHint = hint;
      }
    }
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(Print).CalcDifference(other->GETSCDATA(Print));
      if (aHint < hint) {
        aHint = hint;
      }
    }
#ifdef INCLUDE_XUL
    if (aStopAtFirstDifference && aHint > NS_STYLE_HINT_NONE) return NS_OK;
    if (aHint < NS_STYLE_HINT_MAX) {
      hint = GETSCDATA(XUL).CalcDifference(other->GETSCDATA(XUL));
      if (aHint < hint) {
        aHint = hint;
      }
    }
#endif
  }
  return NS_OK;
}


nsresult StyleContextImpl::EnsureStyleData(nsIPresContext* aPresContext)
{
  nsresult rv = NS_OK;
  NS_ASSERTION(aPresContext, "null presContext argument is illegal and immoral");
  if (nsnull == aPresContext) {
    // no pres context provided, and we have no style data, so send back an error
    return NS_ERROR_FAILURE;
  }

#ifdef SHARE_STYLECONTEXTS
  // See if we already have data...
  if (NS_FAILED(HaveStyleData())) {
    // we were provided a pres context so create a new style data
    mStyleData = nsStyleContextData::Create(aPresContext);
    if (nsnull == mStyleData) {
      rv = NS_ERROR_OUT_OF_MEMORY;
    }
  } else {
    // already have style data - OK!
    rv = NS_OK;
  }
#endif //#ifdef SHARE_STYLECONTEXTS

  return rv;
}

nsresult StyleContextImpl::HaveStyleData(void) const
{
#ifdef SHARE_STYLECONTEXTS
  return (nsnull == mStyleData) ? NS_ERROR_NULL_POINTER : NS_OK;
#else
  return NS_OK;
#endif
}


#ifdef SHARE_STYLECONTEXTS

nsresult StyleContextImpl::ShareStyleData(void)
{
  nsresult result = NS_OK;

  // Enable flag: this is TRUE by default, however the env. var. moz_disable_style_sharing
  // can be set to '1' to disable the sharing before the app is launched
  static char *disableSharing = PR_GetEnv("moz_disable_style_sharing");
  static PRBool bEnableSharing = (disableSharing == nsnull) || 
                                 (*disableSharing != '1');
#ifdef DEBUG
  static PRBool bOnce = PR_FALSE;
  if(!bOnce){
    printf( "Style Data Sharing is %s\n", bEnableSharing ? "Enabled :)" : "Disabled :(" );
    bOnce = PR_TRUE;
  }
#endif

  PRBool bSharingSupported = PR_TRUE;
  if (bEnableSharing) {
    // NOTE: sharing of style data for the GfxScrollFrame is problematic
    //       and is currently disabled. These pseudos indicate the use of a GfxScrollFrame
    //       so we check for them and disallow sharing when any are found.
    //       If you haen;t guessed it, this is a total hack until we can figure out
    //       why the GfxScrollFrame is not happy having its style data shared... 
    //       (See bugzilla bug 39618 which also documents this problem)
    if(mPseudoTag) {
      if(mPseudoTag == nsLayoutAtoms::viewportPseudo ||
         mPseudoTag == nsLayoutAtoms::canvasPseudo ||
         mPseudoTag == nsLayoutAtoms::viewportScrollPseudo ||
         mPseudoTag == nsLayoutAtoms::scrolledContentPseudo ||
         mPseudoTag == nsLayoutAtoms::selectScrolledContentPseudo) {
        bSharingSupported = PR_FALSE;
      } else {
        bSharingSupported = PR_TRUE;
      }
    }
  }

  if (bEnableSharing && bSharingSupported) {
    NS_ASSERTION(mStyleSet, "Expected to have a style set ref...");
    nsIStyleContext *matchingSC = nsnull;

    // save the old crc before replacing it
    PRUint32 oldCRC = mStyleData->GetCRC32();
    
    // set the CRC based on the new data, and retrieve the new value
    mStyleData->SetCRC32();
    PRUint32 newCRC = mStyleData->GetCRC32();

    // if the crc was previously set AND it has changed, notify the styleset
    if((oldCRC != STYLEDATA_NO_CRC)&&
       (oldCRC != newCRC)) {
      result = mStyleSet->UpdateStyleContextKey(oldCRC, newCRC);
#ifdef NOISY_DEBUG
      printf("CRC changed on context: updating from %ld to %ld\n", oldCRC, newCRC);
#endif
      if(NS_FAILED(result)) {
        return result;
      }
    }
    // check if there is a matching context...
    result = mStyleSet->FindMatchingContext(this, &matchingSC);
    if ((NS_SUCCEEDED(result)) && 
        (nsnull != matchingSC)) {
      ShareStyleDataFrom(matchingSC);
#ifdef NOISY_DEBUG
      printf("SC Data Shared :)\n");
#endif
      NS_IF_RELEASE(matchingSC);
    } else {
#ifdef NOISY_DEBUG
      printf("Unique SC Data - Not Shared :(\n");
#endif
    }
  }

  return result;
}

nsresult StyleContextImpl::ShareStyleDataFrom(nsIStyleContext*aStyleDataDonor)
{
  nsresult rv = NS_OK;

  if (aStyleDataDonor) {
    // XXX - static cast is nasty, especially if there are multiple 
    //       nsIStyleContext implementors...
    StyleContextImpl *donor = NS_STATIC_CAST(StyleContextImpl*,aStyleDataDonor);
    
    // get the data from the donor
    nsStyleContextData *pData = donor->mStyleData;
    if (pData != nsnull) {
      NS_ADDREF(pData);
      NS_IF_RELEASE(mStyleData);
      mStyleData = pData;
    }
  }
  return rv;
}

#ifdef DEBUG
long gFalsePos=0;
long gScreenedByCRC=0;
#endif

NS_IMETHODIMP
StyleContextImpl::StyleDataMatches(nsIStyleContext* aStyleContextToMatch, 
                                   PRBool *aMatches)
{
  NS_ASSERTION((aStyleContextToMatch != nsnull) &&
               (aStyleContextToMatch != this) &&           
               (aMatches != nsnull), "invalid parameter");

  nsresult rv = NS_OK;

  // XXX - static cast is nasty, especially if there are multiple 
  //       nsIStyleContext implementors...
  StyleContextImpl* other = NS_STATIC_CAST(StyleContextImpl*,aStyleContextToMatch);
  *aMatches = PR_FALSE;

  // check same pointer value
  if (other->mStyleData != mStyleData) {
    // check using the crc first: 
    // this will get past the vast majority which do not match, 
    // and if it does match then we'll double check with the more complete comparison
    if (other->mStyleData->GetCRC32() == mStyleData->GetCRC32()) {
      // Might match: validate using the more comprehensive (and slower) CalcStyleDifference
      PRInt32 hint = 0;
      CalcStyleDifference(aStyleContextToMatch, hint, PR_TRUE);
#ifdef DEBUG
      if (hint > 0) {
        gFalsePos++;
        // printf("CRC match but CalcStyleDifference shows differences: crc is not sufficient?");
      }
#endif
      *aMatches = (0 == hint) ? PR_TRUE : PR_FALSE;
    }
#ifdef DEBUG
    else
    {
      // in DEBUG we make sure we are not missing any by getting false-negatives on the CRC
      // XXX NOTE: this should be removed when we trust the CRC matching
      //           as this slows it way down
      gScreenedByCRC++;
      /*
      PRInt32 hint = 0;
      CalcStyleDifference(aStyleContextToMatch, hint, PR_TRUE);
      NS_ASSERTION(hint>0,"!!!FALSE-NEGATIVE in StyleMatchesData!!!");
      */
    }
    // printf("False-Pos: %ld - Screened: %ld\n", gFalsePos, gScreenedByCRC);
#endif
  }
  return rv;
}

NS_IMETHODIMP StyleContextImpl::GetStyleContextKey(scKey &aKey) const
{
  aKey = mStyleData->GetCRC32();
  return NS_OK;
}

nsresult StyleContextImpl::UpdateStyleSetCache( void ) const
{
  if (mStyleSet) {
    // add it to the set: the set does NOT addref or release
    return mStyleSet->AddStyleContext((nsIStyleContext *)this);
  } else {
    return NS_ERROR_FAILURE;
  }
}

#endif

void StyleContextImpl::List(FILE* out, PRInt32 aIndent)
{
  // Indent
  PRInt32 ix;
  for (ix = aIndent; --ix >= 0; ) fputs("  ", out);
  fprintf(out, "%p(%d) ", (void*)this, mRefCnt);
  if (nsnull != mPseudoTag) {
    nsAutoString  buffer;
    mPseudoTag->ToString(buffer);
    fputs(buffer, out);
    fputs(" ", out);
  }
  PRInt32 count = GetStyleRuleCount();
  if (0 < count) {
    fputs("{\n", out);

    for (ix = 0; ix < count; ix++) {
      nsIStyleRule* rule = (nsIStyleRule*)mRules->ElementAt(ix);
      rule->List(out, aIndent + 1);
      NS_RELEASE(rule);
    }

    for (ix = aIndent; --ix >= 0; ) fputs("  ", out);
    fputs("}\n", out);
  }
  else {
    fputs("{}\n", out);
  }

  if (nsnull != mChild) {
    StyleContextImpl* child = mChild;
    do {
      child->List(out, aIndent + 1);
      child = child->mNextSibling;
    } while (mChild != child);
  }
  if (nsnull != mEmptyChild) {
    StyleContextImpl* child = mEmptyChild;
    do {
      child->List(out, aIndent + 1);
      child = child->mNextSibling;
    } while (mEmptyChild != child);
  }
}


/******************************************************************************
* SizeOf method:
*  
*  Self (reported as StyleContextImpl's size): 
*    1) sizeof(*this) which gets all of the data members
*    2) adds in the size of the PseudoTag, if there is one
*  
*  Contained / Aggregated data (not reported as StyleContextImpl's size):
*    1) the Style Rules in mRules are not counted as part of sizeof(*this)
*       (though the size of the nsISupportsArray ptr. is) so we need to 
*       count the rules seperately. For each rule in the mRules collection
*       we call the SizeOf method and let it report itself.
*
*  Children / siblings / parents:
*    1) We recurse over the mChild and mEmptyChild instances if they exist.
*       These instances will then be accumulated seperately (not part of 
*       the containing instance's size)
*    2) We recurse over the siblings of the Child and Empty Child instances
*       and count then seperately as well.
*    3) We recurse over our direct siblings (if any).
*   
******************************************************************************/
void StyleContextImpl::SizeOf(nsISizeOfHandler *aSizeOfHandler, PRUint32 &aSize)
{
  NS_ASSERTION(aSizeOfHandler != nsnull, "SizeOf handler cannot be null");

  static PRBool bDetailDumpDone = PR_FALSE;
  if (!bDetailDumpDone) {
    bDetailDumpDone = PR_TRUE;
    PRUint32 totalSize=0;

    printf( "Detailed StyleContextImpl dump: basic class sizes of members\n" );
    printf( "*************************************\n");
    printf( " - StyleFontImpl:          %ld\n", (long)sizeof(GETSCDATA(Font)) );
    totalSize += (long)sizeof(GETSCDATA(Font));
    printf( " - StyleColorImpl:         %ld\n", (long)sizeof(GETSCDATA(Color)) );
    totalSize += (long)sizeof(GETSCDATA(Color));
    printf( " - StyleListImpl:          %ld\n", (long)sizeof(GETSCDATA(List)) );
    totalSize += (long)sizeof(GETSCDATA(List));
    printf( " - StylePositionImpl:      %ld\n", (long)sizeof(GETSCDATA(Position)) );
    totalSize += (long)sizeof(GETSCDATA(Position));
    printf( " - StyleTextImpl:          %ld\n", (long)sizeof(GETSCDATA(Text)) );
    totalSize += (long)sizeof(GETSCDATA(Text));
    printf( " - StyleDisplayImpl:       %ld\n", (long)sizeof(GETSCDATA(Display)) );
    totalSize += (long)sizeof(GETSCDATA(Display));
    printf( " - StyleTableImpl:         %ld\n", (long)sizeof(GETSCDATA(Table)) );
    totalSize += (long)sizeof(GETSCDATA(Table));
    printf( " - StyleContentImpl:       %ld\n", (long)sizeof(GETSCDATA(Content)) );
    totalSize += (long)sizeof(GETSCDATA(Content));
    printf( " - StyleUserInterfaceImpl: %ld\n", (long)sizeof(GETSCDATA(UserInterface)) );
    totalSize += (long)sizeof(GETSCDATA(UserInterface));
	  printf( " - StylePrintImpl:         %ld\n", (long)sizeof(GETSCDATA(Print)));
    totalSize += (long)sizeof(GETSCDATA(Print));
	  printf( " - StyleMarginImpl:         %ld\n", (long)sizeof(GETSCDATA(Margin)));
    totalSize += (long)sizeof(GETSCDATA(Margin));
	  printf( " - StylePaddingImpl:         %ld\n", (long)sizeof(GETSCDATA(Padding)));
    totalSize += (long)sizeof(GETSCDATA(Padding));
	  printf( " - StyleBorderImpl:         %ld\n", (long)sizeof(GETSCDATA(Border)));
    totalSize += (long)sizeof(GETSCDATA(Border));
	  printf( " - StyleOutlineImpl:         %ld\n", (long)sizeof(GETSCDATA(Outline)));
    totalSize += (long)sizeof(GETSCDATA(Outline));
#ifdef INCLUDE_XUL
    printf( " - StyleXULImpl:         %ld\n", (long)sizeof(GETSCDATA(XUL)));
    totalSize += (long)sizeof(GETSCDATA(XUL));
#endif
    printf( " - Total:                  %ld\n", (long)totalSize);
    printf( "*************************************\n");
  }

  // first get the unique items collection
  UNIQUE_STYLE_ITEMS(uniqueItems);

  if(! uniqueItems->AddItem((void*)this) ){
    // object has already been accounted for
    return;
  }

  PRUint32 localSize=0;

  // get or create a tag for this instance
  nsCOMPtr<nsIAtom> tag;
  tag = getter_AddRefs(NS_NewAtom("StyleContextImpl"));
  // get the size of an empty instance and add to the sizeof handler
  aSize = sizeof(*this);
  // add in the size of the member mPseudoTag
  if(mPseudoTag){
    mPseudoTag->SizeOf(aSizeOfHandler, &localSize);
    aSize += localSize;
  }
  aSizeOfHandler->AddSize(tag,aSize);

#ifdef SHARE_STYLECONTEXTS
  // count the style data seperately
  if (mStyleData) {
    mStyleData->SizeOf(aSizeOfHandler,localSize);
  }
#endif

  // size up the rules (if not already done)
  // XXX - overhead of the collection???
  if(mRules && uniqueItems->AddItem(mRules)){
    PRUint32 curRule, ruleCount;
    mRules->Count(&ruleCount);
    if (ruleCount > 0) {
      for (curRule = 0; curRule < ruleCount; curRule++) {
        nsIStyleRule* rule = (nsIStyleRule*)mRules->ElementAt(curRule);
        NS_ASSERTION(rule, "null entry in Rules list is bad news");
        rule->SizeOf(aSizeOfHandler, localSize);
        NS_RELEASE(rule);
      }
    }
  }  
  // now follow up with the child (and empty child) recursion
  if (nsnull != mChild) {
    StyleContextImpl* child = mChild;
    do {
      child->SizeOf(aSizeOfHandler, localSize);
      child = child->mNextSibling;
    } while (mChild != child);
  }
  if (nsnull != mEmptyChild) {
    StyleContextImpl* child = mEmptyChild;
    do {
      child->SizeOf(aSizeOfHandler, localSize);
      child = child->mNextSibling;
    } while (mEmptyChild != child);
  }
  // and finally our direct siblings (if any)
  if (nsnull != mNextSibling) {
    mNextSibling->SizeOf(aSizeOfHandler, localSize);
  }
}

#ifdef DEBUG
static void IndentBy(FILE* out, PRInt32 aIndent) {
  while (--aIndent >= 0) fputs("  ", out);
}
// virtual 
void StyleContextImpl::DumpRegressionData(nsIPresContext* aPresContext, FILE* out, PRInt32 aIndent)
{
  nsAutoString str;

  // FONT
  IndentBy(out,aIndent);
  fprintf(out, "<font %s %s %d />\n", 
          NS_ConvertUCS2toUTF8(GETSCDATA(Font).mFont.name).get(),
          NS_ConvertUCS2toUTF8(GETSCDATA(Font).mFixedFont.name).get(),
          GETSCDATA(Font).mFlags);

  // COLOR
  IndentBy(out,aIndent);
  fprintf(out, "<color data=\"%ld %d %d %d %ld %ld %ld %s %d %s %f\"/>\n", 
    (long)GETSCDATA(Color).mColor,
    (int)GETSCDATA(Color).mBackgroundAttachment,
    (int)GETSCDATA(Color).mBackgroundFlags,
    (int)GETSCDATA(Color).mBackgroundRepeat,
    (long)GETSCDATA(Color).mBackgroundColor,
    (long)GETSCDATA(Color).mBackgroundXPosition,
    (long)GETSCDATA(Color).mBackgroundYPosition,
    NS_ConvertUCS2toUTF8(GETSCDATA(Color).mBackgroundImage).get(),
    (int)GETSCDATA(Color).mCursor,
    NS_ConvertUCS2toUTF8(GETSCDATA(Color).mCursorImage).get(),
    GETSCDATA(Color).mOpacity);

  // SPACING (ie. margin, padding, border, outline)
  IndentBy(out,aIndent);
  fprintf(out, "<spacing data=\"");

  GETSCDATA(Margin).mMargin.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Padding).mPadding.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Border).mBorder.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Border).mBorderRadius.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Outline).mOutlineRadius.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Outline).mOutlineWidth.ToString(str);
  fprintf(out, "%s", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "%d", (int)GETSCDATA(Border).mFloatEdge);
  fprintf(out, "\" />\n");

  // LIST
  IndentBy(out,aIndent);
  fprintf(out, "<list data=\"%d %d %s\" />\n",
    (int)GETSCDATA(List).mListStyleType,
    (int)GETSCDATA(List).mListStyleType,
    NS_ConvertUCS2toUTF8(GETSCDATA(List).mListStyleImage).get());


  // POSITION
  IndentBy(out,aIndent);
  fprintf(out, "<position data=\"%d ", (int)GETSCDATA(Position).mPosition);
  GETSCDATA(Position).mOffset.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Position).mWidth.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Position).mMinWidth.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Position).mMaxWidth.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Position).mHeight.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Position).mMinHeight.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Position).mMaxHeight.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "%d ", (int)GETSCDATA(Position).mBoxSizing);
  GETSCDATA(Position).mZIndex.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "\" />\n");

  // TEXT
  IndentBy(out,aIndent);
  fprintf(out, "<text data=\"%d %d %d %d ",
    (int)GETSCDATA(Text).mTextAlign,
    (int)GETSCDATA(Text).mTextDecoration,
    (int)GETSCDATA(Text).mTextTransform,
    (int)GETSCDATA(Text).mWhiteSpace);
  GETSCDATA(Text).mLetterSpacing.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Text).mLineHeight.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Text).mTextIndent.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Text).mWordSpacing.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Text).mVerticalAlign.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "\" />\n");
  
  // DISPLAY
  IndentBy(out,aIndent);
  fprintf(out, "<display data=\"%d %d %d %d %d %d %d %d %d %ld %ld %ld %ld\" />\n",
    (int)GETSCDATA(Display).mDirection,
    (int)GETSCDATA(Display).mDisplay,
    (int)GETSCDATA(Display).mFloats,
    (int)GETSCDATA(Display).mBreakType,
    (int)GETSCDATA(Display).mBreakBefore,
    (int)GETSCDATA(Display).mBreakAfter,
    (int)GETSCDATA(Display).mVisible,
    (int)GETSCDATA(Display).mOverflow,
    (int)GETSCDATA(Display).mClipFlags,
    (long)GETSCDATA(Display).mClip.x,
    (long)GETSCDATA(Display).mClip.y,
    (long)GETSCDATA(Display).mClip.width,
    (long)GETSCDATA(Display).mClip.height
    );
  
  // TABLE
  IndentBy(out,aIndent);
  fprintf(out, "<table data=\"%d %d %d %d ",
    (int)GETSCDATA(Table).mLayoutStrategy,
    (int)GETSCDATA(Table).mFrame,
    (int)GETSCDATA(Table).mRules,
    (int)GETSCDATA(Table).mBorderCollapse);
  GETSCDATA(Table).mBorderSpacingX.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Table).mBorderSpacingY.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  GETSCDATA(Table).mCellPadding.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "%d %d %ld %ld ",
    (int)GETSCDATA(Table).mCaptionSide,
    (int)GETSCDATA(Table).mEmptyCells,
    (long)GETSCDATA(Table).mCols,
    (long)GETSCDATA(Table).mSpan);
  GETSCDATA(Table).mSpanWidth.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "\" />\n");

  // CONTENT
  IndentBy(out,aIndent);
  fprintf(out, "<content data=\"%ld %ld %ld %ld ",
    (long)GETSCDATA(Content).ContentCount(),
    (long)GETSCDATA(Content).CounterIncrementCount(),
    (long)GETSCDATA(Content).CounterResetCount(),
    (long)GETSCDATA(Content).QuotesCount());
  // XXX: iterate over the content, counters and quotes...
  GETSCDATA(Content).mMarkerOffset.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "\" />\n");

  // UI
  IndentBy(out,aIndent);
  fprintf(out, "<UI data=\"%d %d %d %d %d %d %s\" />\n",
    (int)GETSCDATA(UserInterface).mUserInput,
    (int)GETSCDATA(UserInterface).mUserModify,
    (int)GETSCDATA(UserInterface).mUserSelect,
    (int)GETSCDATA(UserInterface).mUserFocus,
    (int)GETSCDATA(UserInterface).mKeyEquivalent,
    (int)GETSCDATA(UserInterface).mResizer,
    NS_ConvertUCS2toUTF8(GETSCDATA(UserInterface).mBehavior).get());

  // PRINT
  IndentBy(out,aIndent);
  fprintf(out, "<print data=\"%d %d %d %s %ld %ld %d ",
    (int)GETSCDATA(Print).mPageBreakBefore,
    (int)GETSCDATA(Print).mPageBreakAfter,
    (int)GETSCDATA(Print).mPageBreakInside,
    NS_ConvertUCS2toUTF8(GETSCDATA(Print).mPage).get(),
    (long)GETSCDATA(Print).mWidows,
    (long)GETSCDATA(Print).mOrphans,
    (int)GETSCDATA(Print).mMarks);
  GETSCDATA(Print).mSizeWidth.ToString(str);
  fprintf(out, "%s ", NS_ConvertUCS2toUTF8(str).get());
  fprintf(out, "\" />\n");
}
#endif

NS_LAYOUT nsresult
NS_NewStyleContext(nsIStyleContext** aInstancePtrResult,
                   nsIStyleContext* aParentContext,
                   nsIAtom* aPseudoTag,
                   nsISupportsArray* aRules,
                   nsIPresContext* aPresContext)
{
  NS_PRECONDITION(nsnull != aInstancePtrResult, "null ptr");
  if (nsnull == aInstancePtrResult) {
    return NS_ERROR_NULL_POINTER;
  }

  StyleContextImpl* context = new StyleContextImpl(aParentContext, aPseudoTag, 
                                                   aRules, aPresContext);
  if (nsnull == context) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  nsresult result = context->QueryInterface(NS_GET_IID(nsIStyleContext), (void **) aInstancePtrResult);
  context->RemapStyle(aPresContext);  // remap after initial ref-count is set

#ifdef SHARE_STYLECONTEXTS
  context->UpdateStyleSetCache();     // add it to the style set cache now that the CRC is set
#endif

  return result;
}


//----------------------------------------------------------

#ifdef COMPUTE_STYLEDATA_CRC
/*************************************************************************
 *  The table lookup technique was adapted from the algorithm described  *
 *  by Avram Perez, Byte-wise CRC Calculations, IEEE Micro 3, 40 (1983). *
 *************************************************************************/

#define POLYNOMIAL 0x04c11db7L

static PRBool crc_table_initialized;
static PRUint32 crc_table[256];

void gen_crc_table() {
 /* generate the table of CRC remainders for all possible bytes */
  int i, j;  
  PRUint32 crc_accum;
  for ( i = 0;  i < 256;  i++ ) { 
    crc_accum = ( (unsigned long) i << 24 );
    for ( j = 0;  j < 8;  j++ ) { 
      if ( crc_accum & 0x80000000L )
        crc_accum = ( crc_accum << 1 ) ^ POLYNOMIAL;
      else crc_accum = ( crc_accum << 1 ); 
    }
    crc_table[i] = crc_accum; 
  }
  return; 
}

PRUint32 AccumulateCRC(PRUint32 crc_accum, const char *data_blk_ptr, int data_blk_size)  {
  if (!crc_table_initialized) {
    gen_crc_table();
    crc_table_initialized = PR_TRUE;
  }

 /* update the CRC on the data block one byte at a time */
  int i, j;
  for ( j = 0;  j < data_blk_size;  j++ ) { 
    i = ( (int) ( crc_accum >> 24) ^ *data_blk_ptr++ ) & 0xff;
    crc_accum = ( crc_accum << 8 ) ^ crc_table[i]; 
  }
  return crc_accum; 
}


PRUint32 StyleSideCRC(PRUint32 aCrc,const nsStyleSides *aStyleSides)
{
  PRUint32 crc = aCrc;
  nsStyleCoord theCoord;
  aStyleSides->GetLeft(theCoord);
  crc = StyleCoordCRC(crc,&theCoord);
  aStyleSides->GetTop(theCoord);
  crc = StyleCoordCRC(crc,&theCoord);
  aStyleSides->GetRight(theCoord);
  crc = StyleCoordCRC(crc,&theCoord);
  aStyleSides->GetBottom(theCoord);
  crc = StyleCoordCRC(crc,&theCoord);
  return crc;
}

PRUint32 StyleCoordCRC(PRUint32 aCrc, const nsStyleCoord* aCoord)
{
  PRUint32 crc = aCrc;
  crc = AccumulateCRC(crc,(const char *)&aCoord->mUnit,sizeof(aCoord->mUnit));
  // using the mInt part of the union below (float and PRInt32 should be the same size...)
  crc = AccumulateCRC(crc,(const char *)&aCoord->mValue.mInt,sizeof(aCoord->mValue.mInt));
  return crc;
}

PRUint32 StyleMarginCRC(PRUint32 aCrc, const nsMargin *aMargin)
{
  PRUint32 crc = aCrc;
  crc = AccumulateCRC(crc,(const char *)&aMargin->left,sizeof(aMargin->left));
  crc = AccumulateCRC(crc,(const char *)&aMargin->top,sizeof(aMargin->top));
  crc = AccumulateCRC(crc,(const char *)&aMargin->right,sizeof(aMargin->right));
  crc = AccumulateCRC(crc,(const char *)&aMargin->bottom,sizeof(aMargin->bottom));
  return crc;
}

PRUint32 StyleStringCRC(PRUint32 aCrc, const nsString *aString)
{
  PRUint32 crc = aCrc;
  PRUint32 len = aString->Length();
  const PRUnichar *p = aString->GetUnicode();
  if (p) {
    crc = AccumulateCRC(crc,(const char *)p,(len*2));
  }
  crc = AccumulateCRC(crc,(const char *)&len,sizeof(len));
  return crc;
}
#endif // #ifdef COMPUTE_STYLEDATA_CRC

void EnsureBlockDisplay(/*in out*/PRUint8 &display)
{
  // see if the display value is already a block
  switch (display) {
  case NS_STYLE_DISPLAY_NONE :
    // never change display:none *ever*
    break;

  case NS_STYLE_DISPLAY_TABLE :
  case NS_STYLE_DISPLAY_BLOCK :
    // do not muck with these at all - already blocks
    break;

  case NS_STYLE_DISPLAY_LIST_ITEM :
    // do not change list items to blocks - retain the bullet/numbering
    break;

  case NS_STYLE_DISPLAY_TABLE_ROW_GROUP :
  case NS_STYLE_DISPLAY_TABLE_COLUMN :
  case NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP :
  case NS_STYLE_DISPLAY_TABLE_HEADER_GROUP :
  case NS_STYLE_DISPLAY_TABLE_FOOTER_GROUP :
  case NS_STYLE_DISPLAY_TABLE_ROW :
  case NS_STYLE_DISPLAY_TABLE_CELL :
  case NS_STYLE_DISPLAY_TABLE_CAPTION :
    // special cases: don't do anything since these cannot really be floated anyway
    break;

  case NS_STYLE_DISPLAY_INLINE_TABLE :
    // make inline tables into tables
    display = NS_STYLE_DISPLAY_TABLE;
    break;

  default :
    // make it a block
    display = NS_STYLE_DISPLAY_BLOCK;
  }
}