gecko-dev/layout/base/nsStyleChangeList.cpp
2013-08-19 18:55:18 -04:00

130 lines
3.6 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
/*
* a list of the recomputation that needs to be done in response to a
* style change
*/
#include "nsStyleChangeList.h"
#include "nsIContent.h"
static const uint32_t kGrowArrayBy = 10;
nsStyleChangeList::nsStyleChangeList()
: mArray(mBuffer),
mArraySize(kStyleChangeBufferSize),
mCount(0)
{
MOZ_COUNT_CTOR(nsStyleChangeList);
}
nsStyleChangeList::~nsStyleChangeList()
{
MOZ_COUNT_DTOR(nsStyleChangeList);
Clear();
}
nsresult
nsStyleChangeList::ChangeAt(int32_t aIndex, nsIFrame*& aFrame, nsIContent*& aContent,
nsChangeHint& aHint) const
{
if ((0 <= aIndex) && (aIndex < mCount)) {
aFrame = mArray[aIndex].mFrame;
aContent = mArray[aIndex].mContent;
aHint = mArray[aIndex].mHint;
return NS_OK;
}
return NS_ERROR_ILLEGAL_VALUE;
}
nsresult
nsStyleChangeList::ChangeAt(int32_t aIndex, const nsStyleChangeData** aChangeData) const
{
if ((0 <= aIndex) && (aIndex < mCount)) {
*aChangeData = &mArray[aIndex];
return NS_OK;
}
return NS_ERROR_ILLEGAL_VALUE;
}
nsresult
nsStyleChangeList::AppendChange(nsIFrame* aFrame, nsIContent* aContent, nsChangeHint aHint)
{
NS_ASSERTION(aFrame || (aHint & nsChangeHint_ReconstructFrame),
"must have frame");
NS_ASSERTION(aContent || !(aHint & nsChangeHint_ReconstructFrame),
"must have content");
// XXXbz we should make this take Element instead of nsIContent
NS_ASSERTION(!aContent || aContent->IsElement(),
"Shouldn't be trying to restyle non-elements directly");
NS_ASSERTION(!(aHint & nsChangeHint_AllReflowHints) ||
(aHint & nsChangeHint_NeedReflow),
"Reflow hint bits set without actually asking for a reflow");
if ((0 < mCount) && (aHint & nsChangeHint_ReconstructFrame)) { // filter out all other changes for same content
if (aContent) {
for (int32_t index = mCount - 1; index >= 0; --index) {
if (aContent == mArray[index].mContent) { // remove this change
aContent->Release();
mCount--;
if (index < mCount) { // move later changes down
::memmove(&mArray[index], &mArray[index + 1],
(mCount - index) * sizeof(nsStyleChangeData));
}
}
}
}
}
int32_t last = mCount - 1;
if ((0 < mCount) && aFrame && (aFrame == mArray[last].mFrame)) { // same as last frame
NS_UpdateHint(mArray[last].mHint, aHint);
}
else {
if (mCount == mArraySize) {
int32_t newSize = mArraySize + kGrowArrayBy;
nsStyleChangeData* newArray = new nsStyleChangeData[newSize];
if (newArray) {
memcpy(newArray, mArray, mCount * sizeof(nsStyleChangeData));
if (mArray != mBuffer) {
delete [] mArray;
}
mArray = newArray;
mArraySize = newSize;
}
else {
return NS_ERROR_OUT_OF_MEMORY;
}
}
mArray[mCount].mFrame = aFrame;
mArray[mCount].mContent = aContent;
if (aContent) {
aContent->AddRef();
}
mArray[mCount].mHint = aHint;
mCount++;
}
return NS_OK;
}
void
nsStyleChangeList::Clear()
{
for (int32_t index = mCount - 1; index >= 0; --index) {
nsIContent* content = mArray[index].mContent;
if (content) {
content->Release();
}
}
if (mArray != mBuffer) {
delete [] mArray;
mArray = mBuffer;
mArraySize = kStyleChangeBufferSize;
}
mCount = 0;
}