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/* -*- 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
/*
* base class for rendering objects that can be split across lines,
* columns, or pages
*/
#include "nsSplittableFrame.h"
#include "nsContainerFrame.h"
#include "nsFieldSetFrame.h"
#include "nsIFrameInlines.h"
using namespace mozilla;
NS_QUERYFRAME_HEAD(nsSplittableFrame)
NS_QUERYFRAME_ENTRY(nsSplittableFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsIFrame)
// These frame properties cache the first-continuation and first-in-flow frame
// pointers. All nsSplittableFrames other than the first one in the continuation
// chain will have these properties set.
NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(FirstContinuationProperty, nsIFrame);
NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(FirstInFlowProperty, nsIFrame);
void nsSplittableFrame::Init(nsIContent* aContent, nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) {
if (aPrevInFlow) {
// Hook the frame into the flow
SetPrevInFlow(aPrevInFlow);
aPrevInFlow->SetNextInFlow(this);
}
nsIFrame::Init(aContent, aParent, aPrevInFlow);
}
void nsSplittableFrame::Destroy(DestroyContext& aContext) {
// Disconnect from the flow list
if (mPrevContinuation || mNextContinuation) {
RemoveFromFlow(this);
}
// Let the base class destroy the frame
nsIFrame::Destroy(aContext);
}
nsIFrame* nsSplittableFrame::GetPrevContinuation() const {
return mPrevContinuation;
}
void nsSplittableFrame::SetPrevContinuation(nsIFrame* aFrame) {
NS_ASSERTION(!aFrame || Type() == aFrame->Type(),
"setting a prev continuation with incorrect type!");
NS_ASSERTION(!IsInPrevContinuationChain(aFrame, this),
"creating a loop in continuation chain!");
mPrevContinuation = aFrame;
RemoveStateBits(NS_FRAME_IS_FLUID_CONTINUATION);
UpdateFirstContinuationAndFirstInFlowCache();
}
nsIFrame* nsSplittableFrame::GetNextContinuation() const {
return mNextContinuation;
}
void nsSplittableFrame::SetNextContinuation(nsIFrame* aFrame) {
NS_ASSERTION(!aFrame || Type() == aFrame->Type(),
"setting a next continuation with incorrect type!");
NS_ASSERTION(!IsInNextContinuationChain(aFrame, this),
"creating a loop in continuation chain!");
mNextContinuation = aFrame;
if (mNextContinuation) {
mNextContinuation->RemoveStateBits(NS_FRAME_IS_FLUID_CONTINUATION);
}
}
nsIFrame* nsSplittableFrame::FirstContinuation() const {
if (!GetPrevContinuation()) {
MOZ_ASSERT(
!HasProperty(FirstContinuationProperty()),
"The property shouldn't be present on first-continuation itself!");
return const_cast<nsSplittableFrame*>(this);
}
nsIFrame* firstContinuation = GetProperty(FirstContinuationProperty());
MOZ_ASSERT(firstContinuation,
"The property should be set and non-null on all continuations "
"after the first!");
MOZ_ASSERT(!firstContinuation->GetPrevContinuation(),
"First continuation shouldn't have a prev continuation!");
return firstContinuation;
}
nsIFrame* nsSplittableFrame::LastContinuation() const {
nsSplittableFrame* lastContinuation = const_cast<nsSplittableFrame*>(this);
while (lastContinuation->mNextContinuation) {
lastContinuation =
static_cast<nsSplittableFrame*>(lastContinuation->mNextContinuation);
}
MOZ_ASSERT(lastContinuation, "post-condition failed");
return lastContinuation;
}
#ifdef DEBUG
bool nsSplittableFrame::IsInPrevContinuationChain(nsIFrame* aFrame1,
nsIFrame* aFrame2) {
int32_t iterations = 0;
while (aFrame1 && iterations < 10) {
// Bail out after 10 iterations so we don't bog down debug builds too much
if (aFrame1 == aFrame2) return true;
aFrame1 = aFrame1->GetPrevContinuation();
++iterations;
}
return false;
}
bool nsSplittableFrame::IsInNextContinuationChain(nsIFrame* aFrame1,
nsIFrame* aFrame2) {
int32_t iterations = 0;
while (aFrame1 && iterations < 10) {
// Bail out after 10 iterations so we don't bog down debug builds too much
if (aFrame1 == aFrame2) return true;
aFrame1 = aFrame1->GetNextContinuation();
++iterations;
}
return false;
}
#endif
nsIFrame* nsSplittableFrame::GetPrevInFlow() const {
return HasAnyStateBits(NS_FRAME_IS_FLUID_CONTINUATION) ? mPrevContinuation
: nullptr;
}
void nsSplittableFrame::SetPrevInFlow(nsIFrame* aFrame) {
NS_ASSERTION(!aFrame || Type() == aFrame->Type(),
"setting a prev in flow with incorrect type!");
NS_ASSERTION(!IsInPrevContinuationChain(aFrame, this),
"creating a loop in continuation chain!");
mPrevContinuation = aFrame;
AddStateBits(NS_FRAME_IS_FLUID_CONTINUATION);
UpdateFirstContinuationAndFirstInFlowCache();
}
nsIFrame* nsSplittableFrame::GetNextInFlow() const {
return mNextContinuation && mNextContinuation->HasAnyStateBits(
NS_FRAME_IS_FLUID_CONTINUATION)
? mNextContinuation
: nullptr;
}
void nsSplittableFrame::SetNextInFlow(nsIFrame* aFrame) {
NS_ASSERTION(!aFrame || Type() == aFrame->Type(),
"setting a next in flow with incorrect type!");
NS_ASSERTION(!IsInNextContinuationChain(aFrame, this),
"creating a loop in continuation chain!");
mNextContinuation = aFrame;
if (mNextContinuation) {
mNextContinuation->AddStateBits(NS_FRAME_IS_FLUID_CONTINUATION);
}
}
nsIFrame* nsSplittableFrame::FirstInFlow() const {
if (!GetPrevInFlow()) {
MOZ_ASSERT(!HasProperty(FirstInFlowProperty()),
"The property shouldn't be present on first-in-flow itself!");
return const_cast<nsSplittableFrame*>(this);
}
nsIFrame* firstInFlow = GetProperty(FirstInFlowProperty());
MOZ_ASSERT(firstInFlow,
"The property should be set and non-null on all in-flows after "
"the first!");
MOZ_ASSERT(!firstInFlow->GetPrevInFlow(),
"First-in-flow shouldn't have a prev-in-flow!");
return firstInFlow;
}
nsIFrame* nsSplittableFrame::LastInFlow() const {
nsSplittableFrame* lastInFlow = const_cast<nsSplittableFrame*>(this);
while (nsIFrame* next = lastInFlow->GetNextInFlow()) {
lastInFlow = static_cast<nsSplittableFrame*>(next);
}
MOZ_ASSERT(lastInFlow, "post-condition failed");
return lastInFlow;
}
// Remove this frame from the flow. Connects prev in flow and next in flow
void nsSplittableFrame::RemoveFromFlow(nsIFrame* aFrame) {
nsIFrame* prevContinuation = aFrame->GetPrevContinuation();
nsIFrame* nextContinuation = aFrame->GetNextContinuation();
// The new continuation is fluid only if the continuation on both sides
// of the removed frame was fluid
if (aFrame->GetPrevInFlow() && aFrame->GetNextInFlow()) {
if (prevContinuation) {
prevContinuation->SetNextInFlow(nextContinuation);
}
if (nextContinuation) {
nextContinuation->SetPrevInFlow(prevContinuation);
}
} else {
if (prevContinuation) {
prevContinuation->SetNextContinuation(nextContinuation);
}
if (nextContinuation) {
nextContinuation->SetPrevContinuation(prevContinuation);
}
}
// **Note: it is important here that we clear the Next link from aFrame
// BEFORE clearing its Prev link, because in nsContinuingTextFrame,
// SetPrevInFlow() would follow the Next pointers, wiping out the cached
// mFirstContinuation field from each following frame in the list.
aFrame->SetNextInFlow(nullptr);
aFrame->SetPrevInFlow(nullptr);
}
void nsSplittableFrame::UpdateFirstContinuationAndFirstInFlowCache() {
nsIFrame* oldCachedFirstContinuation =
GetProperty(FirstContinuationProperty());
nsIFrame* newFirstContinuation;
if (nsIFrame* prevContinuation = GetPrevContinuation()) {
newFirstContinuation = prevContinuation->FirstContinuation();
SetProperty(FirstContinuationProperty(), newFirstContinuation);
} else {
newFirstContinuation = this;
RemoveProperty(FirstContinuationProperty());
}
if (oldCachedFirstContinuation != newFirstContinuation) {
// Update the first-continuation cache for our next-continuations in the
// chain.
for (nsIFrame* next = GetNextContinuation(); next;
next = next->GetNextContinuation()) {
next->SetProperty(FirstContinuationProperty(), newFirstContinuation);
}
}
nsIFrame* oldCachedFirstInFlow = GetProperty(FirstInFlowProperty());
nsIFrame* newFirstInFlow;
if (nsIFrame* prevInFlow = GetPrevInFlow()) {
newFirstInFlow = prevInFlow->FirstInFlow();
SetProperty(FirstInFlowProperty(), newFirstInFlow);
} else {
newFirstInFlow = this;
RemoveProperty(FirstInFlowProperty());
}
if (oldCachedFirstInFlow != newFirstInFlow) {
// Update the first-in-flow cache for our next-in-flows in the chain.
for (nsIFrame* next = GetNextInFlow(); next; next = next->GetNextInFlow()) {
next->SetProperty(FirstInFlowProperty(), newFirstInFlow);
}
}
}
NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(ConsumedBSizeProperty, nscoord);
nscoord nsSplittableFrame::CalcAndCacheConsumedBSize() {
nsIFrame* prev = GetPrevContinuation();
if (!prev) {
return 0;
}
const auto wm = GetWritingMode();
nscoord bSize = 0;
for (; prev; prev = prev->GetPrevContinuation()) {
if (prev->IsTrueOverflowContainer()) {
// Overflow containers might not get reflowed, and they have no bSize
// anyways.
continue;
}
bSize += prev->ContentBSize(wm);
bool found = false;
nscoord consumed = prev->GetProperty(ConsumedBSizeProperty(), &found);
if (found) {
bSize += consumed;
break;
}
MOZ_ASSERT(!prev->GetPrevContinuation(),
"Property should always be set on prev continuation if not "
"the first continuation");
}
SetProperty(ConsumedBSizeProperty(), bSize);
return bSize;
}
nscoord nsSplittableFrame::GetEffectiveComputedBSize(
const ReflowInput& aReflowInput, nscoord aConsumedBSize) const {
nscoord bSize = aReflowInput.ComputedBSize();
if (bSize == NS_UNCONSTRAINEDSIZE) {
return NS_UNCONSTRAINEDSIZE;
}
bSize -= aConsumedBSize;
// nsFieldSetFrame's inner frames are special since some of their content-box
// BSize may be consumed by positioning it below the legend. So we always
// report zero for true overflow containers here.
// XXXmats: hmm, can we fix this so that the sizes actually adds up instead?
if (IsTrueOverflowContainer() &&
Style()->GetPseudoType() == PseudoStyleType::fieldsetContent) {
for (nsFieldSetFrame* fieldset = do_QueryFrame(GetParent()); fieldset;
fieldset = static_cast<nsFieldSetFrame*>(fieldset->GetPrevInFlow())) {
bSize -= fieldset->LegendSpace();
}
}
// We may have stretched the frame beyond its computed height. Oh well.
return std::max(0, bSize);
}
LogicalSides nsSplittableFrame::GetBlockLevelLogicalSkipSides(
bool aAfterReflow) const {
LogicalSides skip(mWritingMode);
if (MOZ_UNLIKELY(IsTrueOverflowContainer())) {
skip |= eLogicalSideBitsBBoth;
return skip;
}
if (MOZ_UNLIKELY(StyleBorder()->mBoxDecorationBreak ==
StyleBoxDecorationBreak::Clone)) {
return skip;
}
if (GetPrevContinuation()) {
skip |= eLogicalSideBitsBStart;
}
// Always skip block-end side if we have a *later* sibling across column-span
// split.
if (HasColumnSpanSiblings()) {
skip |= eLogicalSideBitsBEnd;
}
if (aAfterReflow) {
nsIFrame* nif = GetNextContinuation();
if (nif && !nif->IsTrueOverflowContainer()) {
skip |= eLogicalSideBitsBEnd;
}
}
return skip;
}