gecko/layout/generic/nsLineBox.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
// vim:cindent:ts=2:et:sw=2:
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* L. David Baron <dbaron@dbaron.org>
* Pierre Phaneuf <pp@ludusdesign.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* representation of one line within a block frame, a CSS line box */
#include "nsLineBox.h"
#include "nsLineLayout.h"
#include "prprf.h"
#include "nsBlockFrame.h"
#include "nsGkAtoms.h"
#include "nsFrameManager.h"
#ifdef IBMBIDI
#include "nsBidiPresUtils.h"
#endif
#ifdef DEBUG
static PRInt32 ctorCount;
PRInt32 nsLineBox::GetCtorCount() { return ctorCount; }
#endif
nsLineBox::nsLineBox(nsIFrame* aFrame, PRInt32 aCount, PRBool aIsBlock)
: mFirstChild(aFrame),
mBounds(0, 0, 0, 0),
mAscent(0),
mData(nsnull)
{
MOZ_COUNT_CTOR(nsLineBox);
#ifdef DEBUG
++ctorCount;
NS_ASSERTION(!aIsBlock || aCount == 1, "Blocks must have exactly one child");
nsIFrame* f = aFrame;
for (PRInt32 n = aCount; n > 0; f = f->GetNextSibling(), --n) {
NS_ASSERTION(aIsBlock == f->GetStyleDisplay()->IsBlockOutside(),
"wrong kind of child frame");
}
#endif
mAllFlags = 0;
#if NS_STYLE_CLEAR_NONE > 0
mFlags.mBreakType = NS_STYLE_CLEAR_NONE;
#endif
SetChildCount(aCount);
MarkDirty();
mFlags.mBlock = aIsBlock;
}
nsLineBox::~nsLineBox()
{
MOZ_COUNT_DTOR(nsLineBox);
Cleanup();
}
nsLineBox*
NS_NewLineBox(nsIPresShell* aPresShell, nsIFrame* aFrame,
PRInt32 aCount, PRBool aIsBlock)
{
return new (aPresShell)nsLineBox(aFrame, aCount, aIsBlock);
}
// Overloaded new operator. Uses an arena (which comes from the presShell)
// to perform the allocation.
void*
nsLineBox::operator new(size_t sz, nsIPresShell* aPresShell) CPP_THROW_NEW
{
return aPresShell->AllocateMisc(sz);
}
// Overloaded delete operator. Doesn't actually free the memory, because we
// use an arena
void
nsLineBox::operator delete(void* aPtr, size_t sz)
{
}
void
nsLineBox::Destroy(nsIPresShell* aPresShell)
{
// Destroy the object. This won't actually free the memory, though
delete this;
// Have the pres shell recycle the memory
aPresShell->FreeMisc(sizeof(*this), (void*)this);
}
void
nsLineBox::Cleanup()
{
if (mData) {
if (IsBlock()) {
delete mBlockData;
}
else {
delete mInlineData;
}
mData = nsnull;
}
}
#ifdef DEBUG
static void
ListFloats(FILE* out, PRInt32 aIndent, const nsFloatCacheList& aFloats)
{
nsFloatCache* fc = aFloats.Head();
while (fc) {
nsFrame::IndentBy(out, aIndent);
nsIFrame* frame = fc->mFloat;
fprintf(out, "floatframe@%p ", static_cast<void*>(frame));
if (frame) {
nsAutoString frameName;
frame->GetFrameName(frameName);
fputs(NS_LossyConvertUTF16toASCII(frameName).get(), out);
}
else {
fputs("\n###!!! NULL out-of-flow frame", out);
}
fprintf(out, "\n");
fc = fc->Next();
}
}
#endif
#ifdef DEBUG
const char *
BreakTypeToString(PRUint8 aBreakType)
{
switch (aBreakType) {
case NS_STYLE_CLEAR_NONE: return "nobr";
case NS_STYLE_CLEAR_LEFT: return "leftbr";
case NS_STYLE_CLEAR_RIGHT: return "rightbr";
case NS_STYLE_CLEAR_LEFT_AND_RIGHT: return "leftbr+rightbr";
case NS_STYLE_CLEAR_LINE: return "linebr";
case NS_STYLE_CLEAR_BLOCK: return "blockbr";
case NS_STYLE_CLEAR_COLUMN: return "columnbr";
case NS_STYLE_CLEAR_PAGE: return "pagebr";
default:
break;
}
return "unknown";
}
char*
nsLineBox::StateToString(char* aBuf, PRInt32 aBufSize) const
{
PR_snprintf(aBuf, aBufSize, "%s,%s,%s,%s,%s,before:%s,after:%s[0x%x]",
IsBlock() ? "block" : "inline",
IsDirty() ? "dirty" : "clean",
IsPreviousMarginDirty() ? "prevmargindirty" : "prevmarginclean",
IsImpactedByFloat() ? "impacted" : "not impacted",
IsLineWrapped() ? "wrapped" : "not wrapped",
BreakTypeToString(GetBreakTypeBefore()),
BreakTypeToString(GetBreakTypeAfter()),
mAllFlags);
return aBuf;
}
void
nsLineBox::List(FILE* out, PRInt32 aIndent) const
{
PRInt32 i;
for (i = aIndent; --i >= 0; ) fputs(" ", out);
char cbuf[100];
fprintf(out, "line %p: count=%d state=%s ",
static_cast<const void*>(this), GetChildCount(),
StateToString(cbuf, sizeof(cbuf)));
if (IsBlock() && !GetCarriedOutBottomMargin().IsZero()) {
fprintf(out, "bm=%d ", GetCarriedOutBottomMargin().get());
}
fprintf(out, "{%d,%d,%d,%d} ",
mBounds.x, mBounds.y, mBounds.width, mBounds.height);
if (mData) {
fprintf(out, "vis-overflow={%d,%d,%d,%d} scr-overflow={%d,%d,%d,%d} ",
mData->mOverflowAreas.VisualOverflow().x,
mData->mOverflowAreas.VisualOverflow().y,
mData->mOverflowAreas.VisualOverflow().width,
mData->mOverflowAreas.VisualOverflow().height,
mData->mOverflowAreas.ScrollableOverflow().x,
mData->mOverflowAreas.ScrollableOverflow().y,
mData->mOverflowAreas.ScrollableOverflow().width,
mData->mOverflowAreas.ScrollableOverflow().height);
}
fprintf(out, "<\n");
nsIFrame* frame = mFirstChild;
PRInt32 n = GetChildCount();
while (--n >= 0) {
frame->List(out, aIndent + 1);
frame = frame->GetNextSibling();
}
for (i = aIndent; --i >= 0; ) fputs(" ", out);
if (HasFloats()) {
fputs("> floats <\n", out);
ListFloats(out, aIndent + 1, mInlineData->mFloats);
for (i = aIndent; --i >= 0; ) fputs(" ", out);
}
fputs(">\n", out);
}
#endif
nsIFrame*
nsLineBox::LastChild() const
{
nsIFrame* frame = mFirstChild;
PRInt32 n = GetChildCount() - 1;
while (--n >= 0) {
frame = frame->GetNextSibling();
}
return frame;
}
PRBool
nsLineBox::IsLastChild(nsIFrame* aFrame) const
{
nsIFrame* lastFrame = LastChild();
return aFrame == lastFrame;
}
PRInt32
nsLineBox::IndexOf(nsIFrame* aFrame) const
{
PRInt32 i, n = GetChildCount();
nsIFrame* frame = mFirstChild;
for (i = 0; i < n; i++) {
if (frame == aFrame) {
return i;
}
frame = frame->GetNextSibling();
}
return -1;
}
PRBool
nsLineBox::IsEmpty() const
{
if (IsBlock())
return mFirstChild->IsEmpty();
PRInt32 n;
nsIFrame *kid;
for (n = GetChildCount(), kid = mFirstChild;
n > 0;
--n, kid = kid->GetNextSibling())
{
if (!kid->IsEmpty())
return PR_FALSE;
}
if (HasBullet()) {
return PR_FALSE;
}
return PR_TRUE;
}
PRBool
nsLineBox::CachedIsEmpty()
{
if (mFlags.mDirty) {
return IsEmpty();
}
if (mFlags.mEmptyCacheValid) {
return mFlags.mEmptyCacheState;
}
PRBool result;
if (IsBlock()) {
result = mFirstChild->CachedIsEmpty();
} else {
PRInt32 n;
nsIFrame *kid;
result = PR_TRUE;
for (n = GetChildCount(), kid = mFirstChild;
n > 0;
--n, kid = kid->GetNextSibling())
{
if (!kid->CachedIsEmpty()) {
result = PR_FALSE;
break;
}
}
if (HasBullet()) {
result = PR_FALSE;
}
}
mFlags.mEmptyCacheValid = PR_TRUE;
mFlags.mEmptyCacheState = result;
return result;
}
void
nsLineBox::DeleteLineList(nsPresContext* aPresContext, nsLineList& aLines,
nsIFrame* aDestructRoot)
{
if (! aLines.empty()) {
// Delete our child frames before doing anything else. In particular
// we do all of this before our base class releases it's hold on the
// view.
#ifdef DEBUG
PRInt32 numFrames = 0;
#endif
for (nsIFrame* child = aLines.front()->mFirstChild; child; ) {
nsIFrame* nextChild = child->GetNextSibling();
child->SetNextSibling(nsnull);
child->DestroyFrom((aDestructRoot) ? aDestructRoot : child);
child = nextChild;
#ifdef DEBUG
numFrames++;
#endif
}
nsIPresShell *shell = aPresContext->PresShell();
do {
nsLineBox* line = aLines.front();
#ifdef DEBUG
numFrames -= line->GetChildCount();
#endif
aLines.pop_front();
line->Destroy(shell);
} while (! aLines.empty());
#ifdef DEBUG
NS_ASSERTION(numFrames == 0, "number of frames deleted does not match");
#endif
}
}
PRBool
nsLineBox::RFindLineContaining(nsIFrame* aFrame,
const nsLineList::iterator& aBegin,
nsLineList::iterator& aEnd,
nsIFrame* aLastFrameBeforeEnd,
PRInt32* aFrameIndexInLine)
{
NS_PRECONDITION(aFrame, "null ptr");
nsIFrame* curFrame = aLastFrameBeforeEnd;
while (aBegin != aEnd) {
--aEnd;
NS_ASSERTION(aEnd->IsLastChild(curFrame), "Unexpected curFrame");
// i is the index of curFrame in aEnd
PRInt32 i = aEnd->GetChildCount() - 1;
while (i >= 0) {
if (curFrame == aFrame) {
*aFrameIndexInLine = i;
return PR_TRUE;
}
--i;
curFrame = curFrame->GetPrevSibling();
}
}
*aFrameIndexInLine = -1;
return PR_FALSE;
}
nsCollapsingMargin
nsLineBox::GetCarriedOutBottomMargin() const
{
NS_ASSERTION(IsBlock(),
"GetCarriedOutBottomMargin called on non-block line.");
return (IsBlock() && mBlockData)
? mBlockData->mCarriedOutBottomMargin
: nsCollapsingMargin();
}
PRBool
nsLineBox::SetCarriedOutBottomMargin(nsCollapsingMargin aValue)
{
PRBool changed = PR_FALSE;
if (IsBlock()) {
if (!aValue.IsZero()) {
if (!mBlockData) {
mBlockData = new ExtraBlockData(mBounds);
}
if (mBlockData) {
changed = aValue != mBlockData->mCarriedOutBottomMargin;
mBlockData->mCarriedOutBottomMargin = aValue;
}
}
else if (mBlockData) {
changed = aValue != mBlockData->mCarriedOutBottomMargin;
mBlockData->mCarriedOutBottomMargin = aValue;
MaybeFreeData();
}
}
return changed;
}
void
nsLineBox::MaybeFreeData()
{
if (mData && mData->mOverflowAreas == nsOverflowAreas(mBounds, mBounds)) {
if (IsInline()) {
if (mInlineData->mFloats.IsEmpty()) {
delete mInlineData;
mInlineData = nsnull;
}
}
else if (mBlockData->mCarriedOutBottomMargin.IsZero()) {
delete mBlockData;
mBlockData = nsnull;
}
}
}
// XXX get rid of this???
nsFloatCache*
nsLineBox::GetFirstFloat()
{
NS_ABORT_IF_FALSE(IsInline(), "block line can't have floats");
return mInlineData ? mInlineData->mFloats.Head() : nsnull;
}
// XXX this might be too eager to free memory
void
nsLineBox::FreeFloats(nsFloatCacheFreeList& aFreeList)
{
NS_ABORT_IF_FALSE(IsInline(), "block line can't have floats");
if (IsInline() && mInlineData) {
if (mInlineData->mFloats.NotEmpty()) {
aFreeList.Append(mInlineData->mFloats);
}
MaybeFreeData();
}
}
void
nsLineBox::AppendFloats(nsFloatCacheFreeList& aFreeList)
{
NS_ABORT_IF_FALSE(IsInline(), "block line can't have floats");
if (IsInline()) {
if (aFreeList.NotEmpty()) {
if (!mInlineData) {
mInlineData = new ExtraInlineData(mBounds);
}
if (mInlineData) {
mInlineData->mFloats.Append(aFreeList);
}
}
}
}
PRBool
nsLineBox::RemoveFloat(nsIFrame* aFrame)
{
NS_ABORT_IF_FALSE(IsInline(), "block line can't have floats");
if (IsInline() && mInlineData) {
nsFloatCache* fc = mInlineData->mFloats.Find(aFrame);
if (fc) {
// Note: the placeholder is part of the line's child list
// and will be removed later.
mInlineData->mFloats.Remove(fc);
delete fc;
MaybeFreeData();
return PR_TRUE;
}
}
return PR_FALSE;
}
void
nsLineBox::SetOverflowAreas(const nsOverflowAreas& aOverflowAreas)
{
NS_FOR_FRAME_OVERFLOW_TYPES(otype) {
NS_ASSERTION(aOverflowAreas.Overflow(otype).width >= 0,
"illegal width for combined area");
NS_ASSERTION(aOverflowAreas.Overflow(otype).height >= 0,
"illegal height for combined area");
}
if (!aOverflowAreas.VisualOverflow().IsEqualInterior(mBounds) ||
!aOverflowAreas.ScrollableOverflow().IsEqualEdges(mBounds)) {
if (!mData) {
if (IsInline()) {
mInlineData = new ExtraInlineData(mBounds);
}
else {
mBlockData = new ExtraBlockData(mBounds);
}
}
mData->mOverflowAreas = aOverflowAreas;
}
else if (mData) {
// Store away new value so that MaybeFreeData compares against
// the right value.
mData->mOverflowAreas = aOverflowAreas;
MaybeFreeData();
}
}
//----------------------------------------------------------------------
static nsLineBox* gDummyLines[1];
nsLineIterator::nsLineIterator()
{
mLines = gDummyLines;
mNumLines = 0;
mIndex = 0;
mRightToLeft = PR_FALSE;
}
nsLineIterator::~nsLineIterator()
{
if (mLines != gDummyLines) {
delete [] mLines;
}
}
/* virtual */ void
nsLineIterator::DisposeLineIterator()
{
delete this;
}
nsresult
nsLineIterator::Init(nsLineList& aLines, PRBool aRightToLeft)
{
mRightToLeft = aRightToLeft;
// Count the lines
PRInt32 numLines = aLines.size();
if (0 == numLines) {
// Use gDummyLines so that we don't need null pointer checks in
// the accessor methods
mLines = gDummyLines;
return NS_OK;
}
// Make a linear array of the lines
mLines = new nsLineBox*[numLines];
if (!mLines) {
// Use gDummyLines so that we don't need null pointer checks in
// the accessor methods
mLines = gDummyLines;
return NS_ERROR_OUT_OF_MEMORY;
}
nsLineBox** lp = mLines;
for (nsLineList::iterator line = aLines.begin(), line_end = aLines.end() ;
line != line_end;
++line)
{
*lp++ = line;
}
mNumLines = numLines;
return NS_OK;
}
PRInt32
nsLineIterator::GetNumLines()
{
return mNumLines;
}
PRBool
nsLineIterator::GetDirection()
{
return mRightToLeft;
}
NS_IMETHODIMP
nsLineIterator::GetLine(PRInt32 aLineNumber,
nsIFrame** aFirstFrameOnLine,
PRInt32* aNumFramesOnLine,
nsRect& aLineBounds,
PRUint32* aLineFlags)
{
NS_ENSURE_ARG_POINTER(aFirstFrameOnLine);
NS_ENSURE_ARG_POINTER(aNumFramesOnLine);
NS_ENSURE_ARG_POINTER(aLineFlags);
if ((aLineNumber < 0) || (aLineNumber >= mNumLines)) {
*aFirstFrameOnLine = nsnull;
*aNumFramesOnLine = 0;
aLineBounds.SetRect(0, 0, 0, 0);
return NS_OK;
}
nsLineBox* line = mLines[aLineNumber];
*aFirstFrameOnLine = line->mFirstChild;
*aNumFramesOnLine = line->GetChildCount();
aLineBounds = line->mBounds;
PRUint32 flags = 0;
if (line->IsBlock()) {
flags |= NS_LINE_FLAG_IS_BLOCK;
}
else {
if (line->HasBreakAfter())
flags |= NS_LINE_FLAG_ENDS_IN_BREAK;
}
*aLineFlags = flags;
return NS_OK;
}
PRInt32
nsLineIterator::FindLineContaining(nsIFrame* aFrame)
{
nsLineBox* line = mLines[0];
PRInt32 lineNumber = 0;
while (lineNumber != mNumLines) {
if (line->Contains(aFrame)) {
return lineNumber;
}
line = mLines[++lineNumber];
}
return -1;
}
#ifdef IBMBIDI
NS_IMETHODIMP
nsLineIterator::CheckLineOrder(PRInt32 aLine,
PRBool *aIsReordered,
nsIFrame **aFirstVisual,
nsIFrame **aLastVisual)
{
NS_ASSERTION (aLine >= 0 && aLine < mNumLines, "aLine out of range!");
nsLineBox* line = mLines[aLine];
if (!line->mFirstChild) { // empty line
*aIsReordered = PR_FALSE;
*aFirstVisual = nsnull;
*aLastVisual = nsnull;
return NS_OK;
}
nsBidiPresUtils* bidiUtils = line->mFirstChild->PresContext()->GetBidiUtils();
nsIFrame* leftmostFrame;
nsIFrame* rightmostFrame;
*aIsReordered = bidiUtils->CheckLineOrder(line->mFirstChild, line->GetChildCount(), &leftmostFrame, &rightmostFrame);
// map leftmost/rightmost to first/last according to paragraph direction
*aFirstVisual = mRightToLeft ? rightmostFrame : leftmostFrame;
*aLastVisual = mRightToLeft ? leftmostFrame : rightmostFrame;
return NS_OK;
}
#endif // IBMBIDI
NS_IMETHODIMP
nsLineIterator::FindFrameAt(PRInt32 aLineNumber,
nscoord aX,
nsIFrame** aFrameFound,
PRBool* aXIsBeforeFirstFrame,
PRBool* aXIsAfterLastFrame)
{
NS_PRECONDITION(aFrameFound && aXIsBeforeFirstFrame && aXIsAfterLastFrame,
"null OUT ptr");
if (!aFrameFound || !aXIsBeforeFirstFrame || !aXIsAfterLastFrame) {
return NS_ERROR_NULL_POINTER;
}
if ((aLineNumber < 0) || (aLineNumber >= mNumLines)) {
return NS_ERROR_INVALID_ARG;
}
nsLineBox* line = mLines[aLineNumber];
if (!line) {
*aFrameFound = nsnull;
*aXIsBeforeFirstFrame = PR_TRUE;
*aXIsAfterLastFrame = PR_FALSE;
return NS_OK;
}
if (line->mBounds.width == 0 && line->mBounds.height == 0)
return NS_ERROR_FAILURE;
nsIFrame* frame = line->mFirstChild;
nsIFrame* closestFromLeft = nsnull;
nsIFrame* closestFromRight = nsnull;
PRInt32 n = line->GetChildCount();
while (n--) {
nsRect rect = frame->GetRect();
if (rect.width > 0) {
// If aX is inside this frame - this is it
if (rect.x <= aX && rect.XMost() > aX) {
closestFromLeft = closestFromRight = frame;
break;
}
if (rect.x < aX) {
if (!closestFromLeft ||
rect.XMost() > closestFromLeft->GetRect().XMost())
closestFromLeft = frame;
}
else {
if (!closestFromRight ||
rect.x < closestFromRight->GetRect().x)
closestFromRight = frame;
}
}
frame = frame->GetNextSibling();
}
if (!closestFromLeft && !closestFromRight) {
// All frames were zero-width. Just take the first one.
closestFromLeft = closestFromRight = line->mFirstChild;
}
*aXIsBeforeFirstFrame = mRightToLeft ? !closestFromRight : !closestFromLeft;
*aXIsAfterLastFrame = mRightToLeft ? !closestFromLeft : !closestFromRight;
if (closestFromLeft == closestFromRight) {
*aFrameFound = closestFromLeft;
}
else if (!closestFromLeft) {
*aFrameFound = closestFromRight;
}
else if (!closestFromRight) {
*aFrameFound = closestFromLeft;
}
else { // we're between two frames
nscoord delta = closestFromRight->GetRect().x - closestFromLeft->GetRect().XMost();
if (aX < closestFromLeft->GetRect().XMost() + delta/2)
*aFrameFound = closestFromLeft;
else
*aFrameFound = closestFromRight;
}
return NS_OK;
}
NS_IMETHODIMP
nsLineIterator::GetNextSiblingOnLine(nsIFrame*& aFrame, PRInt32 aLineNumber)
{
aFrame = aFrame->GetNextSibling();
return NS_OK;
}
//----------------------------------------------------------------------
#ifdef NS_BUILD_REFCNT_LOGGING
nsFloatCacheList::nsFloatCacheList() :
mHead(nsnull)
{
MOZ_COUNT_CTOR(nsFloatCacheList);
}
#endif
nsFloatCacheList::~nsFloatCacheList()
{
DeleteAll();
MOZ_COUNT_DTOR(nsFloatCacheList);
}
void
nsFloatCacheList::DeleteAll()
{
nsFloatCache* c = mHead;
while (c) {
nsFloatCache* next = c->Next();
delete c;
c = next;
}
mHead = nsnull;
}
nsFloatCache*
nsFloatCacheList::Tail() const
{
nsFloatCache* fc = mHead;
while (fc) {
if (!fc->mNext) {
break;
}
fc = fc->mNext;
}
return fc;
}
void
nsFloatCacheList::Append(nsFloatCacheFreeList& aList)
{
NS_PRECONDITION(aList.NotEmpty(), "Appending empty list will fail");
nsFloatCache* tail = Tail();
if (tail) {
NS_ASSERTION(!tail->mNext, "Bogus!");
tail->mNext = aList.mHead;
}
else {
NS_ASSERTION(!mHead, "Bogus!");
mHead = aList.mHead;
}
aList.mHead = nsnull;
aList.mTail = nsnull;
}
nsFloatCache*
nsFloatCacheList::Find(nsIFrame* aOutOfFlowFrame)
{
nsFloatCache* fc = mHead;
while (fc) {
if (fc->mFloat == aOutOfFlowFrame) {
break;
}
fc = fc->Next();
}
return fc;
}
nsFloatCache*
nsFloatCacheList::RemoveAndReturnPrev(nsFloatCache* aElement)
{
nsFloatCache* fc = mHead;
nsFloatCache* prev = nsnull;
while (fc) {
if (fc == aElement) {
if (prev) {
prev->mNext = fc->mNext;
} else {
mHead = fc->mNext;
}
return prev;
}
prev = fc;
fc = fc->mNext;
}
return nsnull;
}
//----------------------------------------------------------------------
#ifdef NS_BUILD_REFCNT_LOGGING
nsFloatCacheFreeList::nsFloatCacheFreeList() :
mTail(nsnull)
{
MOZ_COUNT_CTOR(nsFloatCacheFreeList);
}
nsFloatCacheFreeList::~nsFloatCacheFreeList()
{
MOZ_COUNT_DTOR(nsFloatCacheFreeList);
}
#endif
void
nsFloatCacheFreeList::Append(nsFloatCacheList& aList)
{
NS_PRECONDITION(aList.NotEmpty(), "Appending empty list will fail");
if (mTail) {
NS_ASSERTION(!mTail->mNext, "Bogus");
mTail->mNext = aList.mHead;
}
else {
NS_ASSERTION(!mHead, "Bogus");
mHead = aList.mHead;
}
mTail = aList.Tail();
aList.mHead = nsnull;
}
void
nsFloatCacheFreeList::Remove(nsFloatCache* aElement)
{
nsFloatCache* prev = nsFloatCacheList::RemoveAndReturnPrev(aElement);
if (mTail == aElement) {
mTail = prev;
}
}
void
nsFloatCacheFreeList::DeleteAll()
{
nsFloatCacheList::DeleteAll();
mTail = nsnull;
}
nsFloatCache*
nsFloatCacheFreeList::Alloc(nsIFrame* aFloat)
{
NS_PRECONDITION(aFloat->GetStateBits() & NS_FRAME_OUT_OF_FLOW,
"This is a float cache, why isn't the frame out-of-flow?");
nsFloatCache* fc = mHead;
if (mHead) {
if (mHead == mTail) {
mHead = mTail = nsnull;
}
else {
mHead = fc->mNext;
}
fc->mNext = nsnull;
}
else {
fc = new nsFloatCache();
}
fc->mFloat = aFloat;
return fc;
}
void
nsFloatCacheFreeList::Append(nsFloatCache* aFloat)
{
NS_ASSERTION(!aFloat->mNext, "Bogus!");
aFloat->mNext = nsnull;
if (mTail) {
NS_ASSERTION(!mTail->mNext, "Bogus!");
mTail->mNext = aFloat;
mTail = aFloat;
}
else {
NS_ASSERTION(!mHead, "Bogus!");
mHead = mTail = aFloat;
}
}
//----------------------------------------------------------------------
nsFloatCache::nsFloatCache()
: mFloat(nsnull),
mNext(nsnull)
{
MOZ_COUNT_CTOR(nsFloatCache);
}
#ifdef NS_BUILD_REFCNT_LOGGING
nsFloatCache::~nsFloatCache()
{
MOZ_COUNT_DTOR(nsFloatCache);
}
#endif