gecko-dev/layout/generic/nsLineBox.cpp

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27 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* representation of one line within a block frame, a CSS line box */
#include "nsLineBox.h"
#include "mozilla/ArenaObjectID.h"
#include "mozilla/Assertions.h"
#include "mozilla/Likely.h"
#include "mozilla/PresShell.h"
#include "mozilla/Sprintf.h"
#include "mozilla/WritingModes.h"
#include "mozilla/ToString.h"
#include "nsBidiPresUtils.h"
#include "nsIFrame.h"
#include "nsIFrameInlines.h"
#include "nsPresArena.h"
#include "nsPrintfCString.h"
#include "nsWindowSizes.h"
#ifdef DEBUG
static int32_t ctorCount;
int32_t nsLineBox::GetCtorCount() { return ctorCount; }
#endif
#ifndef _MSC_VER
// static nsLineBox constant; initialized in the header file.
const uint32_t nsLineBox::kMinChildCountForHashtable;
#endif
using namespace mozilla;
nsLineBox::nsLineBox(nsIFrame* aFrame, int32_t aCount, bool aIsBlock)
: mFirstChild(aFrame),
mWritingMode(),
mContainerSize(-1, -1),
mBounds(WritingMode()), // mBounds will be initialized with the correct
// writing mode when it is set
mFrames(),
mAscent(),
mAllFlags(0),
mData(nullptr) {
// Assert that the union elements chosen for initialisation are at
// least as large as all other elements in their respective unions, so
// as to ensure that no parts are missed.
static_assert(sizeof(mFrames) >= sizeof(mChildCount), "nsLineBox init #1");
static_assert(sizeof(mAllFlags) >= sizeof(mFlags), "nsLineBox init #2");
static_assert(sizeof(mData) >= sizeof(mBlockData), "nsLineBox init #3");
static_assert(sizeof(mData) >= sizeof(mInlineData), "nsLineBox init #4");
MOZ_COUNT_CTOR(nsLineBox);
#ifdef DEBUG
++ctorCount;
NS_ASSERTION(!aIsBlock || aCount == 1, "Blocks must have exactly one child");
nsIFrame* f = aFrame;
for (int32_t n = aCount; n > 0; f = f->GetNextSibling(), --n) {
NS_ASSERTION(aIsBlock == f->IsBlockOutside(), "wrong kind of child frame");
}
#endif
static_assert(static_cast<int>(StyleClear::Max) <= 15,
"FlagBits needs more bits to store the full range of "
"break type ('clear') values");
mChildCount = aCount;
MarkDirty();
mFlags.mBlock = aIsBlock;
}
nsLineBox::~nsLineBox() {
MOZ_COUNT_DTOR(nsLineBox);
if (MOZ_UNLIKELY(mFlags.mHasHashedFrames)) {
delete mFrames;
}
Cleanup();
}
nsLineBox* NS_NewLineBox(PresShell* aPresShell, nsIFrame* aFrame,
bool aIsBlock) {
return new (aPresShell) nsLineBox(aFrame, 1, aIsBlock);
}
nsLineBox* NS_NewLineBox(PresShell* aPresShell, nsLineBox* aFromLine,
nsIFrame* aFrame, int32_t aCount) {
nsLineBox* newLine = new (aPresShell) nsLineBox(aFrame, aCount, false);
newLine->NoteFramesMovedFrom(aFromLine);
newLine->mContainerSize = aFromLine->mContainerSize;
return newLine;
}
void nsLineBox::AddSizeOfExcludingThis(nsWindowSizes& aSizes) const {
if (mFlags.mHasHashedFrames) {
aSizes.mLayoutFramePropertiesSize +=
mFrames->ShallowSizeOfIncludingThis(aSizes.mState.mMallocSizeOf);
}
}
void nsLineBox::StealHashTableFrom(nsLineBox* aFromLine,
uint32_t aFromLineNewCount) {
MOZ_ASSERT(!mFlags.mHasHashedFrames);
MOZ_ASSERT(GetChildCount() >= int32_t(aFromLineNewCount));
mFrames = aFromLine->mFrames;
mFlags.mHasHashedFrames = 1;
aFromLine->mFlags.mHasHashedFrames = 0;
aFromLine->mChildCount = aFromLineNewCount;
// remove aFromLine's frames that aren't on this line
nsIFrame* f = aFromLine->mFirstChild;
for (uint32_t i = 0; i < aFromLineNewCount; f = f->GetNextSibling(), ++i) {
mFrames->RemoveEntry(f);
}
}
void nsLineBox::NoteFramesMovedFrom(nsLineBox* aFromLine) {
uint32_t fromCount = aFromLine->GetChildCount();
uint32_t toCount = GetChildCount();
MOZ_ASSERT(toCount <= fromCount, "moved more frames than aFromLine has");
uint32_t fromNewCount = fromCount - toCount;
if (MOZ_LIKELY(!aFromLine->mFlags.mHasHashedFrames)) {
aFromLine->mChildCount = fromNewCount;
MOZ_ASSERT(toCount < kMinChildCountForHashtable);
} else if (fromNewCount < kMinChildCountForHashtable) {
// aFromLine has a hash table but will not have it after moving the frames
// so this line can steal the hash table if it needs it.
if (toCount >= kMinChildCountForHashtable) {
StealHashTableFrom(aFromLine, fromNewCount);
} else {
delete aFromLine->mFrames;
aFromLine->mFlags.mHasHashedFrames = 0;
aFromLine->mChildCount = fromNewCount;
}
} else {
// aFromLine still needs a hash table.
if (toCount < kMinChildCountForHashtable) {
// remove the moved frames from it
nsIFrame* f = mFirstChild;
for (uint32_t i = 0; i < toCount; f = f->GetNextSibling(), ++i) {
aFromLine->mFrames->RemoveEntry(f);
}
} else if (toCount <= fromNewCount) {
// This line needs a hash table, allocate a hash table for it since that
// means fewer hash ops.
nsIFrame* f = mFirstChild;
for (uint32_t i = 0; i < toCount; f = f->GetNextSibling(), ++i) {
aFromLine->mFrames->RemoveEntry(f); // toCount RemoveEntry
}
SwitchToHashtable(); // toCount PutEntry
} else {
// This line needs a hash table, but it's fewer hash ops to steal
// aFromLine's hash table and allocate a new hash table for that line.
StealHashTableFrom(aFromLine, fromNewCount); // fromNewCount RemoveEntry
aFromLine->SwitchToHashtable(); // fromNewCount PutEntry
}
}
}
void* nsLineBox::operator new(size_t sz, PresShell* aPresShell) {
return aPresShell->AllocateByObjectID(eArenaObjectID_nsLineBox, sz);
}
void nsLineBox::Destroy(PresShell* aPresShell) {
this->nsLineBox::~nsLineBox();
aPresShell->FreeByObjectID(eArenaObjectID_nsLineBox, this);
}
void nsLineBox::Cleanup() {
if (mData) {
if (IsBlock()) {
delete mBlockData;
} else {
delete mInlineData;
}
mData = nullptr;
}
}
#ifdef DEBUG_FRAME_DUMP
static void ListFloats(FILE* out, const char* aPrefix,
const nsFloatCacheList& aFloats) {
nsFloatCache* fc = aFloats.Head();
while (fc) {
nsCString str(aPrefix);
nsIFrame* frame = fc->mFloat;
str += nsPrintfCString("floatframe@%p ", static_cast<void*>(frame));
if (frame) {
nsAutoString frameName;
frame->GetFrameName(frameName);
str += NS_ConvertUTF16toUTF8(frameName).get();
} else {
str += "\n###!!! NULL out-of-flow frame";
}
fprintf_stderr(out, "%s\n", str.get());
fc = fc->Next();
}
}
/* static */ const char* nsLineBox::BreakTypeToString(StyleClear aBreakType) {
switch (aBreakType) {
case StyleClear::None:
return "nobr";
case StyleClear::Left:
return "leftbr";
case StyleClear::Right:
return "rightbr";
case StyleClear::Both:
return "leftbr+rightbr";
case StyleClear::Line:
return "linebr";
case StyleClear::Max:
return "leftbr+rightbr+linebr";
}
return "unknown";
}
char* nsLineBox::StateToString(char* aBuf, int32_t aBufSize) const {
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, int32_t aIndent,
nsIFrame::ListFlags aFlags) const {
nsCString str;
while (aIndent-- > 0) {
str += " ";
}
List(out, str.get(), aFlags);
}
void nsLineBox::List(FILE* out, const char* aPrefix,
nsIFrame::ListFlags aFlags) const {
nsCString str(aPrefix);
char cbuf[100];
str += nsPrintfCString("line@%p count=%d state=%s ",
static_cast<const void*>(this), GetChildCount(),
StateToString(cbuf, sizeof(cbuf)));
if (IsBlock() && !GetCarriedOutBEndMargin().IsZero()) {
const nscoord bm = GetCarriedOutBEndMargin().get();
str += nsPrintfCString("bm=%s ",
nsIFrame::ConvertToString(bm, aFlags).c_str());
}
nsRect bounds = GetPhysicalBounds();
str +=
nsPrintfCString("%s ", nsIFrame::ConvertToString(bounds, aFlags).c_str());
if (mWritingMode.IsVertical() || mWritingMode.IsBidiRTL()) {
str += nsPrintfCString(
"wm=%s cs=(%s) logical-rect=%s ", ToString(mWritingMode).c_str(),
nsIFrame::ConvertToString(mContainerSize, aFlags).c_str(),
nsIFrame::ConvertToString(mBounds, mWritingMode, aFlags).c_str());
}
if (mData) {
const nsRect vo = mData->mOverflowAreas.InkOverflow();
const nsRect so = mData->mOverflowAreas.ScrollableOverflow();
if (!vo.IsEqualEdges(bounds) || !so.IsEqualEdges(bounds)) {
str += nsPrintfCString("ink-overflow=%s scr-overflow=%s ",
nsIFrame::ConvertToString(vo, aFlags).c_str(),
nsIFrame::ConvertToString(so, aFlags).c_str());
}
}
fprintf_stderr(out, "%s<\n", str.get());
nsIFrame* frame = mFirstChild;
int32_t n = GetChildCount();
nsCString pfx(aPrefix);
pfx += " ";
while (--n >= 0) {
frame->List(out, pfx.get(), aFlags);
frame = frame->GetNextSibling();
}
if (HasFloats()) {
fprintf_stderr(out, "%s> floats <\n", aPrefix);
ListFloats(out, pfx.get(), mInlineData->mFloats);
}
fprintf_stderr(out, "%s>\n", aPrefix);
}
nsIFrame* nsLineBox::LastChild() const {
nsIFrame* frame = mFirstChild;
int32_t n = GetChildCount() - 1;
while (--n >= 0) {
frame = frame->GetNextSibling();
}
return frame;
}
#endif
int32_t nsLineBox::IndexOf(nsIFrame* aFrame) const {
int32_t i, n = GetChildCount();
nsIFrame* frame = mFirstChild;
for (i = 0; i < n; i++) {
if (frame == aFrame) {
return i;
}
frame = frame->GetNextSibling();
}
return -1;
}
int32_t nsLineBox::RIndexOf(nsIFrame* aFrame,
nsIFrame* aLastFrameInLine) const {
nsIFrame* frame = aLastFrameInLine;
for (int32_t i = GetChildCount() - 1; i >= 0; --i) {
MOZ_ASSERT(i != 0 || frame == mFirstChild,
"caller provided incorrect last frame");
if (frame == aFrame) {
return i;
}
frame = frame->GetPrevSibling();
}
return -1;
}
bool nsLineBox::IsEmpty() const {
if (IsBlock()) return mFirstChild->IsEmpty();
int32_t n;
nsIFrame* kid;
for (n = GetChildCount(), kid = mFirstChild; n > 0;
--n, kid = kid->GetNextSibling()) {
if (!kid->IsEmpty()) return false;
}
if (HasMarker()) {
return false;
}
return true;
}
bool nsLineBox::CachedIsEmpty() {
if (mFlags.mDirty) {
return IsEmpty();
}
if (mFlags.mEmptyCacheValid) {
return mFlags.mEmptyCacheState;
}
bool result;
if (IsBlock()) {
result = mFirstChild->CachedIsEmpty();
} else {
int32_t n;
nsIFrame* kid;
result = true;
for (n = GetChildCount(), kid = mFirstChild; n > 0;
--n, kid = kid->GetNextSibling()) {
if (!kid->CachedIsEmpty()) {
result = false;
break;
}
}
if (HasMarker()) {
result = false;
}
}
mFlags.mEmptyCacheValid = true;
mFlags.mEmptyCacheState = result;
return result;
}
void nsLineBox::DeleteLineList(nsPresContext* aPresContext, nsLineList& aLines,
nsIFrame* aDestructRoot, nsFrameList* aFrames,
PostDestroyData& aPostDestroyData) {
PresShell* presShell = aPresContext->PresShell();
// Keep our line list and frame list up to date as we
// remove frames, in case something wants to traverse the
// frame tree while we're destroying.
while (!aLines.empty()) {
nsLineBox* line = aLines.front();
if (MOZ_UNLIKELY(line->mFlags.mHasHashedFrames)) {
line->SwitchToCounter(); // Avoid expensive has table removals.
}
while (line->GetChildCount() > 0) {
nsIFrame* child = aFrames->RemoveFirstChild();
MOZ_DIAGNOSTIC_ASSERT(child->PresContext() == aPresContext);
MOZ_DIAGNOSTIC_ASSERT(child == line->mFirstChild, "Lines out of sync");
line->mFirstChild = aFrames->FirstChild();
line->NoteFrameRemoved(child);
child->DestroyFrom(aDestructRoot, aPostDestroyData);
}
MOZ_DIAGNOSTIC_ASSERT(line == aLines.front(),
"destroying child frames messed up our lines!");
aLines.pop_front();
line->Destroy(presShell);
}
}
bool nsLineBox::RFindLineContaining(nsIFrame* aFrame,
const nsLineList::iterator& aBegin,
nsLineList::iterator& aEnd,
nsIFrame* aLastFrameBeforeEnd,
int32_t* aFrameIndexInLine) {
MOZ_ASSERT(aFrame, "null ptr");
nsIFrame* curFrame = aLastFrameBeforeEnd;
while (aBegin != aEnd) {
--aEnd;
NS_ASSERTION(aEnd->LastChild() == curFrame, "Unexpected curFrame");
if (MOZ_UNLIKELY(aEnd->mFlags.mHasHashedFrames) &&
!aEnd->Contains(aFrame)) {
if (aEnd->mFirstChild) {
curFrame = aEnd->mFirstChild->GetPrevSibling();
}
continue;
}
// i is the index of curFrame in aEnd
int32_t i = aEnd->GetChildCount() - 1;
while (i >= 0) {
if (curFrame == aFrame) {
*aFrameIndexInLine = i;
return true;
}
--i;
curFrame = curFrame->GetPrevSibling();
}
MOZ_ASSERT(!aEnd->mFlags.mHasHashedFrames, "Contains lied to us!");
}
*aFrameIndexInLine = -1;
return false;
}
nsCollapsingMargin nsLineBox::GetCarriedOutBEndMargin() const {
NS_ASSERTION(IsBlock(), "GetCarriedOutBEndMargin called on non-block line.");
return (IsBlock() && mBlockData) ? mBlockData->mCarriedOutBEndMargin
: nsCollapsingMargin();
}
bool nsLineBox::SetCarriedOutBEndMargin(nsCollapsingMargin aValue) {
bool changed = false;
if (IsBlock()) {
if (!aValue.IsZero()) {
if (!mBlockData) {
mBlockData = new ExtraBlockData(GetPhysicalBounds());
}
changed = aValue != mBlockData->mCarriedOutBEndMargin;
mBlockData->mCarriedOutBEndMargin = aValue;
} else if (mBlockData) {
changed = aValue != mBlockData->mCarriedOutBEndMargin;
mBlockData->mCarriedOutBEndMargin = aValue;
MaybeFreeData();
}
}
return changed;
}
void nsLineBox::MaybeFreeData() {
nsRect bounds = GetPhysicalBounds();
if (mData && mData->mOverflowAreas == nsOverflowAreas(bounds, bounds)) {
if (IsInline()) {
if (mInlineData->mFloats.IsEmpty()) {
delete mInlineData;
mInlineData = nullptr;
}
} else if (mBlockData->mCarriedOutBEndMargin.IsZero()) {
delete mBlockData;
mBlockData = nullptr;
}
}
}
// XXX get rid of this???
nsFloatCache* nsLineBox::GetFirstFloat() {
MOZ_ASSERT(IsInline(), "block line can't have floats");
return mInlineData ? mInlineData->mFloats.Head() : nullptr;
}
// XXX this might be too eager to free memory
void nsLineBox::FreeFloats(nsFloatCacheFreeList& aFreeList) {
MOZ_ASSERT(IsInline(), "block line can't have floats");
if (IsInline() && mInlineData) {
if (mInlineData->mFloats.NotEmpty()) {
aFreeList.Append(mInlineData->mFloats);
}
MaybeFreeData();
}
}
void nsLineBox::AppendFloats(nsFloatCacheFreeList& aFreeList) {
MOZ_ASSERT(IsInline(), "block line can't have floats");
if (IsInline()) {
if (aFreeList.NotEmpty()) {
if (!mInlineData) {
mInlineData = new ExtraInlineData(GetPhysicalBounds());
}
mInlineData->mFloats.Append(aFreeList);
}
}
}
bool nsLineBox::RemoveFloat(nsIFrame* aFrame) {
MOZ_ASSERT(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 true;
}
}
return false;
}
void nsLineBox::SetFloatEdges(nscoord aStart, nscoord aEnd) {
MOZ_ASSERT(IsInline(), "block line can't have float edges");
if (!mInlineData) {
mInlineData = new ExtraInlineData(GetPhysicalBounds());
}
mInlineData->mFloatEdgeIStart = aStart;
mInlineData->mFloatEdgeIEnd = aEnd;
}
void nsLineBox::ClearFloatEdges() {
MOZ_ASSERT(IsInline(), "block line can't have float edges");
if (mInlineData) {
mInlineData->mFloatEdgeIStart = nscoord_MIN;
mInlineData->mFloatEdgeIEnd = nscoord_MIN;
}
}
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");
}
nsRect bounds = GetPhysicalBounds();
if (!aOverflowAreas.InkOverflow().IsEqualInterior(bounds) ||
!aOverflowAreas.ScrollableOverflow().IsEqualEdges(bounds)) {
if (!mData) {
if (IsInline()) {
mInlineData = new ExtraInlineData(bounds);
} else {
mBlockData = new ExtraBlockData(bounds);
}
}
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 = false;
}
nsLineIterator::~nsLineIterator() {
if (mLines != gDummyLines) {
delete[] mLines;
}
}
/* virtual */
void nsLineIterator::DisposeLineIterator() { delete this; }
nsresult nsLineIterator::Init(nsLineList& aLines, bool aRightToLeft) {
mRightToLeft = aRightToLeft;
// Count the lines
int32_t 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;
}
int32_t nsLineIterator::GetNumLines() const { return mNumLines; }
bool nsLineIterator::GetDirection() { return mRightToLeft; }
Result<nsILineIterator::LineInfo, nsresult> nsLineIterator::GetLine(
int32_t aLineNumber) const {
if ((aLineNumber < 0) || (aLineNumber >= mNumLines)) {
return Err(NS_ERROR_FAILURE);
}
LineInfo structure;
nsLineBox* line = mLines[aLineNumber];
structure.mFirstFrameOnLine = line->mFirstChild;
structure.mNumFramesOnLine = line->GetChildCount();
structure.mLineBounds = line->GetPhysicalBounds();
structure.mIsWrapped = line->IsLineWrapped();
return structure;
}
int32_t nsLineIterator::FindLineContaining(nsIFrame* aFrame,
int32_t aStartLine) {
MOZ_ASSERT(aStartLine <= mNumLines, "Bogus line numbers");
int32_t lineNumber = aStartLine;
while (lineNumber != mNumLines) {
nsLineBox* line = mLines[lineNumber];
if (line->Contains(aFrame)) {
return lineNumber;
}
++lineNumber;
}
return -1;
}
NS_IMETHODIMP
nsLineIterator::CheckLineOrder(int32_t aLine, bool* 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 = false;
*aFirstVisual = nullptr;
*aLastVisual = nullptr;
return NS_OK;
}
nsIFrame* leftmostFrame;
nsIFrame* rightmostFrame;
*aIsReordered =
nsBidiPresUtils::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;
}
NS_IMETHODIMP
nsLineIterator::FindFrameAt(int32_t aLineNumber, nsPoint aPos,
nsIFrame** aFrameFound,
bool* aPosIsBeforeFirstFrame,
bool* aPosIsAfterLastFrame) const {
MOZ_ASSERT(aFrameFound && aPosIsBeforeFirstFrame && aPosIsAfterLastFrame,
"null OUT ptr");
if (!aFrameFound || !aPosIsBeforeFirstFrame || !aPosIsAfterLastFrame) {
return NS_ERROR_NULL_POINTER;
}
if ((aLineNumber < 0) || (aLineNumber >= mNumLines)) {
return NS_ERROR_INVALID_ARG;
}
nsLineBox* line = mLines[aLineNumber];
if (!line) {
*aFrameFound = nullptr;
*aPosIsBeforeFirstFrame = true;
*aPosIsAfterLastFrame = false;
return NS_OK;
}
if (line->ISize() == 0 && line->BSize() == 0) return NS_ERROR_FAILURE;
nsIFrame* frame = line->mFirstChild;
nsIFrame* closestFromStart = nullptr;
nsIFrame* closestFromEnd = nullptr;
WritingMode wm = line->mWritingMode;
nsSize containerSize = line->mContainerSize;
LogicalPoint pos(wm, aPos, containerSize);
int32_t n = line->GetChildCount();
while (n--) {
LogicalRect rect = frame->GetLogicalRect(wm, containerSize);
if (rect.ISize(wm) > 0) {
// If pos.I() is inside this frame - this is it
if (rect.IStart(wm) <= pos.I(wm) && rect.IEnd(wm) > pos.I(wm)) {
closestFromStart = closestFromEnd = frame;
break;
}
if (rect.IStart(wm) < pos.I(wm)) {
if (!closestFromStart ||
rect.IEnd(wm) >
closestFromStart->GetLogicalRect(wm, containerSize).IEnd(wm))
closestFromStart = frame;
} else {
if (!closestFromEnd ||
rect.IStart(wm) <
closestFromEnd->GetLogicalRect(wm, containerSize).IStart(wm))
closestFromEnd = frame;
}
}
frame = frame->GetNextSibling();
}
if (!closestFromStart && !closestFromEnd) {
// All frames were zero-width. Just take the first one.
closestFromStart = closestFromEnd = line->mFirstChild;
}
*aPosIsBeforeFirstFrame = mRightToLeft ? !closestFromEnd : !closestFromStart;
*aPosIsAfterLastFrame = mRightToLeft ? !closestFromStart : !closestFromEnd;
if (closestFromStart == closestFromEnd) {
*aFrameFound = closestFromStart;
} else if (!closestFromStart) {
*aFrameFound = closestFromEnd;
} else if (!closestFromEnd) {
*aFrameFound = closestFromStart;
} else { // we're between two frames
nscoord delta =
closestFromEnd->GetLogicalRect(wm, containerSize).IStart(wm) -
closestFromStart->GetLogicalRect(wm, containerSize).IEnd(wm);
if (pos.I(wm) <
closestFromStart->GetLogicalRect(wm, containerSize).IEnd(wm) +
delta / 2) {
*aFrameFound = closestFromStart;
} else {
*aFrameFound = closestFromEnd;
}
}
return NS_OK;
}
NS_IMETHODIMP
nsLineIterator::GetNextSiblingOnLine(nsIFrame*& aFrame,
int32_t aLineNumber) const {
aFrame = aFrame->GetNextSibling();
return NS_OK;
}
//----------------------------------------------------------------------
#ifdef NS_BUILD_REFCNT_LOGGING
nsFloatCacheList::nsFloatCacheList() : mHead(nullptr) {
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 = nullptr;
}
nsFloatCache* nsFloatCacheList::Tail() const {
nsFloatCache* fc = mHead;
while (fc) {
if (!fc->mNext) {
break;
}
fc = fc->mNext;
}
return fc;
}
void nsFloatCacheList::Append(nsFloatCacheFreeList& aList) {
MOZ_ASSERT(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 = nullptr;
aList.mTail = nullptr;
}
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 = nullptr;
while (fc) {
if (fc == aElement) {
if (prev) {
prev->mNext = fc->mNext;
} else {
mHead = fc->mNext;
}
return prev;
}
prev = fc;
fc = fc->mNext;
}
return nullptr;
}
//----------------------------------------------------------------------
#ifdef NS_BUILD_REFCNT_LOGGING
nsFloatCacheFreeList::nsFloatCacheFreeList() : mTail(nullptr) {
MOZ_COUNT_CTOR(nsFloatCacheFreeList);
}
nsFloatCacheFreeList::~nsFloatCacheFreeList() {
MOZ_COUNT_DTOR(nsFloatCacheFreeList);
}
#endif
void nsFloatCacheFreeList::Append(nsFloatCacheList& aList) {
MOZ_ASSERT(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 = nullptr;
}
void nsFloatCacheFreeList::Remove(nsFloatCache* aElement) {
nsFloatCache* prev = nsFloatCacheList::RemoveAndReturnPrev(aElement);
if (mTail == aElement) {
mTail = prev;
}
}
void nsFloatCacheFreeList::DeleteAll() {
nsFloatCacheList::DeleteAll();
mTail = nullptr;
}
nsFloatCache* nsFloatCacheFreeList::Alloc(nsIFrame* aFloat) {
MOZ_ASSERT(aFloat->HasAnyStateBits(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 = nullptr;
} else {
mHead = fc->mNext;
}
fc->mNext = nullptr;
} else {
fc = new nsFloatCache();
}
fc->mFloat = aFloat;
return fc;
}
void nsFloatCacheFreeList::Append(nsFloatCache* aFloat) {
NS_ASSERTION(!aFloat->mNext, "Bogus!");
aFloat->mNext = nullptr;
if (mTail) {
NS_ASSERTION(!mTail->mNext, "Bogus!");
mTail->mNext = aFloat;
mTail = aFloat;
} else {
NS_ASSERTION(!mHead, "Bogus!");
mHead = mTail = aFloat;
}
}
//----------------------------------------------------------------------
nsFloatCache::nsFloatCache() : mFloat(nullptr), mNext(nullptr) {
MOZ_COUNT_CTOR(nsFloatCache);
}
#ifdef NS_BUILD_REFCNT_LOGGING
nsFloatCache::~nsFloatCache() { MOZ_COUNT_DTOR(nsFloatCache); }
#endif