gecko/layout/base/nsFrameManager.cpp
L. David Baron 5ef4421fa5 Bug 781360 patch 3: Rename {nsIFrame,nsStyleContext,nsComputedDOMStyle}::GetStyle* to Style*, since they can never return null. r=dholbert
Except for the changes in:
  layout/generic/nsIFrame.h (part)
  layout/style/nsComputedDOMStyle.h (all)
  layout/style/nsRuleNode.cpp (part)
  layout/style/nsStyleContext.cpp (part)
  layout/style/nsStyleContext.h (part)
(see patch 3b in the bug), this patch was written with the sed script:
s/\<GetStyle\(Font\|Color\|List\|Text\|Visibility\|Quotes\|UserInterface\|TableBorder\|SVG\|Background\|Position\|TextReset\|Display\|Content\|UIReset\|Table\|Margin\|Padding\|Border\|Outline\|XUL\|SVGReset\|Column\)\>/Style\1/g
2013-02-16 13:51:02 -08:00

2018 lines
76 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim:cindent:ts=2:et:sw=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/.
*
* 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
* 04/20/2000 IBM Corp. OS/2 VisualAge build.
*/
/* storage of the frame tree and information about it */
#include "mozilla/DebugOnly.h"
#include "nscore.h"
#include "nsPresContext.h"
#include "nsIPresShell.h"
#include "nsStyleSet.h"
#include "nsCSSFrameConstructor.h"
#include "nsStyleContext.h"
#include "nsStyleChangeList.h"
#include "nsIServiceManager.h"
#include "nsCOMPtr.h"
#include "prthread.h"
#include "plhash.h"
#include "nsPlaceholderFrame.h"
#include "nsContainerFrame.h"
#include "nsBlockFrame.h"
#include "nsGkAtoms.h"
#include "nsCSSAnonBoxes.h"
#include "nsCSSPseudoElements.h"
#ifdef DEBUG
#include "nsIStyleRule.h"
#endif
#include "nsILayoutHistoryState.h"
#include "nsPresState.h"
#include "nsIContent.h"
#include "nsINameSpaceManager.h"
#include "nsIDocument.h"
#include "nsIScrollableFrame.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMHTMLCollection.h"
#include "nsIFormControl.h"
#include "nsIDOMElement.h"
#include "nsIDOMHTMLFormElement.h"
#include "nsIForm.h"
#include "nsContentUtils.h"
#include "nsReadableUtils.h"
#include "nsUnicharUtils.h"
#include "nsError.h"
#include "nsLayoutUtils.h"
#include "nsAutoPtr.h"
#include "imgIRequest.h"
#include "nsTransitionManager.h"
#include "RestyleTracker.h"
#include "nsAbsoluteContainingBlock.h"
#include "nsFrameManager.h"
#include "nsRuleProcessorData.h"
#include "sampler.h"
#ifdef ACCESSIBILITY
#include "nsAccessibilityService.h"
#endif
#ifdef DEBUG
//#define NOISY_DEBUG
//#define DEBUG_UNDISPLAYED_MAP
#else
#undef NOISY_DEBUG
#undef DEBUG_UNDISPLAYED_MAP
#endif
#ifdef NOISY_DEBUG
#define NOISY_TRACE(_msg) \
printf("%s",_msg);
#define NOISY_TRACE_FRAME(_msg,_frame) \
printf("%s ",_msg); nsFrame::ListTag(stdout,_frame); printf("\n");
#else
#define NOISY_TRACE(_msg);
#define NOISY_TRACE_FRAME(_msg,_frame);
#endif
using namespace mozilla;
using namespace mozilla::dom;
//----------------------------------------------------------------------
struct PlaceholderMapEntry : public PLDHashEntryHdr {
// key (the out of flow frame) can be obtained through placeholder frame
nsPlaceholderFrame *placeholderFrame;
};
static bool
PlaceholderMapMatchEntry(PLDHashTable *table, const PLDHashEntryHdr *hdr,
const void *key)
{
const PlaceholderMapEntry *entry =
static_cast<const PlaceholderMapEntry*>(hdr);
NS_ASSERTION(entry->placeholderFrame->GetOutOfFlowFrame() !=
(void*)0xdddddddd,
"Dead placeholder in placeholder map");
return entry->placeholderFrame->GetOutOfFlowFrame() == key;
}
static PLDHashTableOps PlaceholderMapOps = {
PL_DHashAllocTable,
PL_DHashFreeTable,
PL_DHashVoidPtrKeyStub,
PlaceholderMapMatchEntry,
PL_DHashMoveEntryStub,
PL_DHashClearEntryStub,
PL_DHashFinalizeStub,
NULL
};
//----------------------------------------------------------------------
// XXXldb This seems too complicated for what I think it's doing, and it
// should also be using pldhash rather than plhash to use less memory.
class UndisplayedNode {
public:
UndisplayedNode(nsIContent* aContent, nsStyleContext* aStyle)
: mContent(aContent),
mStyle(aStyle),
mNext(nullptr)
{
MOZ_COUNT_CTOR(UndisplayedNode);
}
NS_HIDDEN ~UndisplayedNode()
{
MOZ_COUNT_DTOR(UndisplayedNode);
// Delete mNext iteratively to avoid blowing up the stack (bug 460461).
UndisplayedNode *cur = mNext;
while (cur) {
UndisplayedNode *next = cur->mNext;
cur->mNext = nullptr;
delete cur;
cur = next;
}
}
nsCOMPtr<nsIContent> mContent;
nsRefPtr<nsStyleContext> mStyle;
UndisplayedNode* mNext;
};
class nsFrameManagerBase::UndisplayedMap {
public:
UndisplayedMap(uint32_t aNumBuckets = 16) NS_HIDDEN;
~UndisplayedMap(void) NS_HIDDEN;
NS_HIDDEN_(UndisplayedNode*) GetFirstNode(nsIContent* aParentContent);
NS_HIDDEN_(nsresult) AddNodeFor(nsIContent* aParentContent,
nsIContent* aChild, nsStyleContext* aStyle);
NS_HIDDEN_(void) RemoveNodeFor(nsIContent* aParentContent,
UndisplayedNode* aNode);
NS_HIDDEN_(void) RemoveNodesFor(nsIContent* aParentContent);
// Removes all entries from the hash table
NS_HIDDEN_(void) Clear(void);
protected:
NS_HIDDEN_(PLHashEntry**) GetEntryFor(nsIContent* aParentContent);
NS_HIDDEN_(void) AppendNodeFor(UndisplayedNode* aNode,
nsIContent* aParentContent);
PLHashTable* mTable;
PLHashEntry** mLastLookup;
};
//----------------------------------------------------------------------
nsFrameManager::~nsFrameManager()
{
NS_ASSERTION(!mPresShell, "nsFrameManager::Destroy never called");
}
nsresult
nsFrameManager::Init(nsStyleSet* aStyleSet)
{
if (!mPresShell) {
NS_ERROR("null pres shell");
return NS_ERROR_FAILURE;
}
if (!aStyleSet) {
NS_ERROR("null style set");
return NS_ERROR_FAILURE;
}
mStyleSet = aStyleSet;
return NS_OK;
}
void
nsFrameManager::Destroy()
{
NS_ASSERTION(mPresShell, "Frame manager already shut down.");
// Destroy the frame hierarchy.
mPresShell->SetIgnoreFrameDestruction(true);
// Unregister all placeholders before tearing down the frame tree
nsFrameManager::ClearPlaceholderFrameMap();
if (mRootFrame) {
mRootFrame->Destroy();
mRootFrame = nullptr;
}
delete mUndisplayedMap;
mUndisplayedMap = nullptr;
mPresShell = nullptr;
}
//----------------------------------------------------------------------
// Placeholder frame functions
nsPlaceholderFrame*
nsFrameManager::GetPlaceholderFrameFor(const nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null param unexpected");
if (mPlaceholderMap.ops) {
PlaceholderMapEntry *entry = static_cast<PlaceholderMapEntry*>
(PL_DHashTableOperate(const_cast<PLDHashTable*>(&mPlaceholderMap),
aFrame, PL_DHASH_LOOKUP));
if (PL_DHASH_ENTRY_IS_BUSY(entry)) {
return entry->placeholderFrame;
}
}
return nullptr;
}
nsresult
nsFrameManager::RegisterPlaceholderFrame(nsPlaceholderFrame* aPlaceholderFrame)
{
NS_PRECONDITION(aPlaceholderFrame, "null param unexpected");
NS_PRECONDITION(nsGkAtoms::placeholderFrame == aPlaceholderFrame->GetType(),
"unexpected frame type");
if (!mPlaceholderMap.ops) {
if (!PL_DHashTableInit(&mPlaceholderMap, &PlaceholderMapOps, nullptr,
sizeof(PlaceholderMapEntry), 16)) {
mPlaceholderMap.ops = nullptr;
return NS_ERROR_OUT_OF_MEMORY;
}
}
PlaceholderMapEntry *entry = static_cast<PlaceholderMapEntry*>(PL_DHashTableOperate(&mPlaceholderMap,
aPlaceholderFrame->GetOutOfFlowFrame(),
PL_DHASH_ADD));
if (!entry)
return NS_ERROR_OUT_OF_MEMORY;
NS_ASSERTION(!entry->placeholderFrame, "Registering a placeholder for a frame that already has a placeholder!");
entry->placeholderFrame = aPlaceholderFrame;
return NS_OK;
}
void
nsFrameManager::UnregisterPlaceholderFrame(nsPlaceholderFrame* aPlaceholderFrame)
{
NS_PRECONDITION(aPlaceholderFrame, "null param unexpected");
NS_PRECONDITION(nsGkAtoms::placeholderFrame == aPlaceholderFrame->GetType(),
"unexpected frame type");
if (mPlaceholderMap.ops) {
PL_DHashTableOperate(&mPlaceholderMap,
aPlaceholderFrame->GetOutOfFlowFrame(),
PL_DHASH_REMOVE);
}
}
static PLDHashOperator
UnregisterPlaceholders(PLDHashTable* table, PLDHashEntryHdr* hdr,
uint32_t number, void* arg)
{
PlaceholderMapEntry* entry = static_cast<PlaceholderMapEntry*>(hdr);
entry->placeholderFrame->SetOutOfFlowFrame(nullptr);
return PL_DHASH_NEXT;
}
void
nsFrameManager::ClearPlaceholderFrameMap()
{
if (mPlaceholderMap.ops) {
PL_DHashTableEnumerate(&mPlaceholderMap, UnregisterPlaceholders, nullptr);
PL_DHashTableFinish(&mPlaceholderMap);
mPlaceholderMap.ops = nullptr;
}
}
//----------------------------------------------------------------------
nsStyleContext*
nsFrameManager::GetUndisplayedContent(nsIContent* aContent)
{
if (!aContent || !mUndisplayedMap)
return nullptr;
nsIContent* parent = aContent->GetParent();
for (UndisplayedNode* node = mUndisplayedMap->GetFirstNode(parent);
node; node = node->mNext) {
if (node->mContent == aContent)
return node->mStyle;
}
return nullptr;
}
void
nsFrameManager::SetUndisplayedContent(nsIContent* aContent,
nsStyleContext* aStyleContext)
{
NS_PRECONDITION(!aStyleContext->GetPseudo(),
"Should only have actual elements here");
#ifdef DEBUG_UNDISPLAYED_MAP
static int i = 0;
printf("SetUndisplayedContent(%d): p=%p \n", i++, (void *)aContent);
#endif
NS_ASSERTION(!GetUndisplayedContent(aContent),
"Already have an undisplayed context entry for aContent");
if (! mUndisplayedMap) {
mUndisplayedMap = new UndisplayedMap;
}
nsIContent* parent = aContent->GetParent();
NS_ASSERTION(parent || (mPresShell && mPresShell->GetDocument() &&
mPresShell->GetDocument()->GetRootElement() == aContent),
"undisplayed content must have a parent, unless it's the root "
"element");
mUndisplayedMap->AddNodeFor(parent, aContent, aStyleContext);
}
void
nsFrameManager::ChangeUndisplayedContent(nsIContent* aContent,
nsStyleContext* aStyleContext)
{
NS_ASSERTION(mUndisplayedMap, "no existing undisplayed content");
#ifdef DEBUG_UNDISPLAYED_MAP
static int i = 0;
printf("ChangeUndisplayedContent(%d): p=%p \n", i++, (void *)aContent);
#endif
for (UndisplayedNode* node = mUndisplayedMap->GetFirstNode(aContent->GetParent());
node; node = node->mNext) {
if (node->mContent == aContent) {
node->mStyle = aStyleContext;
return;
}
}
NS_NOTREACHED("no existing undisplayed content");
}
void
nsFrameManager::ClearUndisplayedContentIn(nsIContent* aContent,
nsIContent* aParentContent)
{
#ifdef DEBUG_UNDISPLAYED_MAP
static int i = 0;
printf("ClearUndisplayedContent(%d): content=%p parent=%p --> ", i++, (void *)aContent, (void*)aParentContent);
#endif
if (mUndisplayedMap) {
UndisplayedNode* node = mUndisplayedMap->GetFirstNode(aParentContent);
while (node) {
if (node->mContent == aContent) {
mUndisplayedMap->RemoveNodeFor(aParentContent, node);
#ifdef DEBUG_UNDISPLAYED_MAP
printf( "REMOVED!\n");
#endif
#ifdef DEBUG
// make sure that there are no more entries for the same content
nsStyleContext *context = GetUndisplayedContent(aContent);
NS_ASSERTION(context == nullptr, "Found more undisplayed content data after removal");
#endif
return;
}
node = node->mNext;
}
}
}
void
nsFrameManager::ClearAllUndisplayedContentIn(nsIContent* aParentContent)
{
#ifdef DEBUG_UNDISPLAYED_MAP
static int i = 0;
printf("ClearAllUndisplayedContentIn(%d): parent=%p \n", i++, (void*)aParentContent);
#endif
if (mUndisplayedMap) {
mUndisplayedMap->RemoveNodesFor(aParentContent);
}
// Need to look at aParentContent's content list due to XBL insertions.
// Nodes in aParentContent's content list do not have aParentContent as a
// parent, but are treated as children of aParentContent. We get access to
// the content list via GetXBLChildNodesFor and just ignore any nodes we
// don't care about.
nsINodeList* list =
aParentContent->OwnerDoc()->BindingManager()->GetXBLChildNodesFor(aParentContent);
if (list) {
uint32_t length;
list->GetLength(&length);
for (uint32_t i = 0; i < length; ++i) {
nsIContent* child = list->Item(i);
if (child->GetParent() != aParentContent) {
ClearUndisplayedContentIn(child, child->GetParent());
}
}
}
}
//----------------------------------------------------------------------
nsresult
nsFrameManager::AppendFrames(nsIFrame* aParentFrame,
ChildListID aListID,
nsFrameList& aFrameList)
{
if (aParentFrame->IsAbsoluteContainer() &&
aListID == aParentFrame->GetAbsoluteListID()) {
return aParentFrame->GetAbsoluteContainingBlock()->
AppendFrames(aParentFrame, aListID, aFrameList);
} else {
return aParentFrame->AppendFrames(aListID, aFrameList);
}
}
nsresult
nsFrameManager::InsertFrames(nsIFrame* aParentFrame,
ChildListID aListID,
nsIFrame* aPrevFrame,
nsFrameList& aFrameList)
{
NS_PRECONDITION(!aPrevFrame || (!aPrevFrame->GetNextContinuation()
|| (((aPrevFrame->GetNextContinuation()->GetStateBits() & NS_FRAME_IS_OVERFLOW_CONTAINER))
&& !(aPrevFrame->GetStateBits() & NS_FRAME_IS_OVERFLOW_CONTAINER))),
"aPrevFrame must be the last continuation in its chain!");
if (aParentFrame->IsAbsoluteContainer() &&
aListID == aParentFrame->GetAbsoluteListID()) {
return aParentFrame->GetAbsoluteContainingBlock()->
InsertFrames(aParentFrame, aListID, aPrevFrame, aFrameList);
} else {
return aParentFrame->InsertFrames(aListID, aPrevFrame, aFrameList);
}
}
nsresult
nsFrameManager::RemoveFrame(ChildListID aListID,
nsIFrame* aOldFrame)
{
bool wasDestroyingFrames = mIsDestroyingFrames;
mIsDestroyingFrames = true;
// In case the reflow doesn't invalidate anything since it just leaves
// a gap where the old frame was, we invalidate it here. (This is
// reasonably likely to happen when removing a last child in a way
// that doesn't change the size of the parent.)
// This has to sure to invalidate the entire overflow rect; this
// is important in the presence of absolute positioning
aOldFrame->InvalidateFrameForRemoval();
NS_ASSERTION(!aOldFrame->GetPrevContinuation() ||
// exception for nsCSSFrameConstructor::RemoveFloatingFirstLetterFrames
aOldFrame->GetType() == nsGkAtoms::textFrame,
"Must remove first continuation.");
NS_ASSERTION(!(aOldFrame->GetStateBits() & NS_FRAME_OUT_OF_FLOW &&
GetPlaceholderFrameFor(aOldFrame)),
"Must call RemoveFrame on placeholder for out-of-flows.");
nsresult rv = NS_OK;
nsIFrame* parentFrame = aOldFrame->GetParent();
if (parentFrame->IsAbsoluteContainer() &&
aListID == parentFrame->GetAbsoluteListID()) {
parentFrame->GetAbsoluteContainingBlock()->
RemoveFrame(parentFrame, aListID, aOldFrame);
} else {
rv = parentFrame->RemoveFrame(aListID, aOldFrame);
}
mIsDestroyingFrames = wasDestroyingFrames;
return rv;
}
//----------------------------------------------------------------------
void
nsFrameManager::NotifyDestroyingFrame(nsIFrame* aFrame)
{
nsIContent* content = aFrame->GetContent();
if (content && content->GetPrimaryFrame() == aFrame) {
ClearAllUndisplayedContentIn(content);
}
}
#ifdef DEBUG
static void
DumpContext(nsIFrame* aFrame, nsStyleContext* aContext)
{
if (aFrame) {
fputs("frame: ", stdout);
nsAutoString name;
aFrame->GetFrameName(name);
fputs(NS_LossyConvertUTF16toASCII(name).get(), stdout);
fprintf(stdout, " (%p)", static_cast<void*>(aFrame));
}
if (aContext) {
fprintf(stdout, " style: %p ", static_cast<void*>(aContext));
nsIAtom* pseudoTag = aContext->GetPseudo();
if (pseudoTag) {
nsAutoString buffer;
pseudoTag->ToString(buffer);
fputs(NS_LossyConvertUTF16toASCII(buffer).get(), stdout);
fputs(" ", stdout);
}
fputs("{}\n", stdout);
}
}
static void
VerifySameTree(nsStyleContext* aContext1, nsStyleContext* aContext2)
{
nsStyleContext* top1 = aContext1;
nsStyleContext* top2 = aContext2;
nsStyleContext* parent;
for (;;) {
parent = top1->GetParent();
if (!parent)
break;
top1 = parent;
}
for (;;) {
parent = top2->GetParent();
if (!parent)
break;
top2 = parent;
}
NS_ASSERTION(top1 == top2,
"Style contexts are not in the same style context tree");
}
static void
VerifyContextParent(nsPresContext* aPresContext, nsIFrame* aFrame,
nsStyleContext* aContext, nsStyleContext* aParentContext)
{
// get the contexts not provided
if (!aContext) {
aContext = aFrame->StyleContext();
}
if (!aParentContext) {
// Get the correct parent context from the frame
// - if the frame is a placeholder, we get the out of flow frame's context
// as the parent context instead of asking the frame
// get the parent context from the frame (indirectly)
nsIFrame* providerFrame = aFrame->GetParentStyleContextFrame();
if (providerFrame)
aParentContext = providerFrame->StyleContext();
// aParentContext could still be null
}
NS_ASSERTION(aContext, "Failure to get required contexts");
nsStyleContext* actualParentContext = aContext->GetParent();
if (aParentContext) {
if (aParentContext != actualParentContext) {
DumpContext(aFrame, aContext);
if (aContext == aParentContext) {
NS_ERROR("Using parent's style context");
}
else {
NS_ERROR("Wrong parent style context");
fputs("Wrong parent style context: ", stdout);
DumpContext(nullptr, actualParentContext);
fputs("should be using: ", stdout);
DumpContext(nullptr, aParentContext);
VerifySameTree(actualParentContext, aParentContext);
fputs("\n", stdout);
}
}
}
else {
if (actualParentContext) {
NS_ERROR("Have parent context and shouldn't");
DumpContext(aFrame, aContext);
fputs("Has parent context: ", stdout);
DumpContext(nullptr, actualParentContext);
fputs("Should be null\n\n", stdout);
}
}
nsStyleContext* childStyleIfVisited = aContext->GetStyleIfVisited();
// Either childStyleIfVisited has aContext->GetParent()->GetStyleIfVisited()
// as the parent or it has a different rulenode from aContext _and_ has
// aContext->GetParent() as the parent.
if (childStyleIfVisited &&
!((childStyleIfVisited->RuleNode() != aContext->RuleNode() &&
childStyleIfVisited->GetParent() == aContext->GetParent()) ||
childStyleIfVisited->GetParent() ==
aContext->GetParent()->GetStyleIfVisited())) {
NS_ERROR("Visited style has wrong parent");
DumpContext(aFrame, aContext);
fputs("\n", stdout);
}
}
static void
VerifyStyleTree(nsPresContext* aPresContext, nsIFrame* aFrame,
nsStyleContext* aParentContext)
{
nsStyleContext* context = aFrame->StyleContext();
VerifyContextParent(aPresContext, aFrame, context, nullptr);
nsIFrame::ChildListIterator lists(aFrame);
for (; !lists.IsDone(); lists.Next()) {
nsFrameList::Enumerator childFrames(lists.CurrentList());
for (; !childFrames.AtEnd(); childFrames.Next()) {
nsIFrame* child = childFrames.get();
if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW)) {
// only do frames that are in flow
if (nsGkAtoms::placeholderFrame == child->GetType()) {
// placeholder: first recurse and verify the out of flow frame,
// then verify the placeholder's context
nsIFrame* outOfFlowFrame =
nsPlaceholderFrame::GetRealFrameForPlaceholder(child);
// recurse to out of flow frame, letting the parent context get resolved
do {
VerifyStyleTree(aPresContext, outOfFlowFrame, nullptr);
} while ((outOfFlowFrame = outOfFlowFrame->GetNextContinuation()));
// verify placeholder using the parent frame's context as
// parent context
VerifyContextParent(aPresContext, child, nullptr, nullptr);
}
else { // regular frame
VerifyStyleTree(aPresContext, child, nullptr);
}
}
}
}
// do additional contexts
int32_t contextIndex = -1;
while (1) {
nsStyleContext* extraContext = aFrame->GetAdditionalStyleContext(++contextIndex);
if (extraContext) {
VerifyContextParent(aPresContext, aFrame, extraContext, context);
}
else {
break;
}
}
}
void
nsFrameManager::DebugVerifyStyleTree(nsIFrame* aFrame)
{
if (aFrame) {
nsStyleContext* context = aFrame->StyleContext();
nsStyleContext* parentContext = context->GetParent();
VerifyStyleTree(GetPresContext(), aFrame, parentContext);
}
}
#endif // DEBUG
// aContent must be the content for the frame in question, which may be
// :before/:after content
static void
TryStartingTransition(nsPresContext *aPresContext, nsIContent *aContent,
nsStyleContext *aOldStyleContext,
nsRefPtr<nsStyleContext> *aNewStyleContext /* inout */)
{
if (!aContent || !aContent->IsElement()) {
return;
}
// Notify the transition manager, and if it starts a transition,
// it will give us back a transition-covering style rule which
// we'll use to get *another* style context. We want to ignore
// any already-running transitions, but cover up any that we're
// currently starting with their start value so we don't start
// them again for descendants that inherit that value.
nsCOMPtr<nsIStyleRule> coverRule =
aPresContext->TransitionManager()->StyleContextChanged(
aContent->AsElement(), aOldStyleContext, *aNewStyleContext);
if (coverRule) {
nsCOMArray<nsIStyleRule> rules;
rules.AppendObject(coverRule);
*aNewStyleContext = aPresContext->StyleSet()->
ResolveStyleByAddingRules(*aNewStyleContext, rules);
}
}
static inline Element*
ElementForStyleContext(nsIContent* aParentContent,
nsIFrame* aFrame,
nsCSSPseudoElements::Type aPseudoType)
{
// We don't expect XUL tree stuff here.
NS_PRECONDITION(aPseudoType == nsCSSPseudoElements::ePseudo_NotPseudoElement ||
aPseudoType == nsCSSPseudoElements::ePseudo_AnonBox ||
aPseudoType < nsCSSPseudoElements::ePseudo_PseudoElementCount,
"Unexpected pseudo");
// XXX see the comments about the various element confusion in
// ReResolveStyleContext.
if (aPseudoType == nsCSSPseudoElements::ePseudo_NotPseudoElement) {
return aFrame->GetContent()->AsElement();
}
if (aPseudoType == nsCSSPseudoElements::ePseudo_AnonBox) {
return nullptr;
}
if (aPseudoType == nsCSSPseudoElements::ePseudo_firstLetter) {
NS_ASSERTION(aFrame->GetType() == nsGkAtoms::letterFrame,
"firstLetter pseudoTag without a nsFirstLetterFrame");
nsBlockFrame* block = nsBlockFrame::GetNearestAncestorBlock(aFrame);
return block->GetContent()->AsElement();
}
nsIContent* content = aParentContent ? aParentContent : aFrame->GetContent();
return content->AsElement();
}
static nsIFrame*
GetPrevContinuationWithPossiblySameStyle(nsIFrame* aFrame)
{
// Account for {ib} splits when looking for "prevContinuation". In
// particular, for the first-continuation of a part of an {ib} split we
// want to use the special prevsibling of the special prevsibling of
// aFrame, which should have the same style context as aFrame itself.
// In particular, if aFrame is the first continuation of an inline part
// of an {ib} split then its special prevsibling is a block, and the
// special prevsibling of _that_ is an inline, just like aFrame.
// Similarly, if aFrame is the first continuation of a block part of an
// {ib} split (an {ib} wrapper block), then its special prevsibling is
// an inline and the special prevsibling of that is either another {ib}
// wrapper block block or null.
nsIFrame *prevContinuation = aFrame->GetPrevContinuation();
if (!prevContinuation && (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL)) {
// We're the first continuation, so we can just get the frame
// property directly
prevContinuation = static_cast<nsIFrame*>(
aFrame->Properties().Get(nsIFrame::IBSplitSpecialPrevSibling()));
if (prevContinuation) {
prevContinuation = static_cast<nsIFrame*>(
prevContinuation->Properties().Get(nsIFrame::IBSplitSpecialPrevSibling()));
}
}
return prevContinuation;
}
nsresult
nsFrameManager::ReparentStyleContext(nsIFrame* aFrame)
{
if (nsGkAtoms::placeholderFrame == aFrame->GetType()) {
// Also reparent the out-of-flow and all its continuations.
nsIFrame* outOfFlow =
nsPlaceholderFrame::GetRealFrameForPlaceholder(aFrame);
NS_ASSERTION(outOfFlow, "no out-of-flow frame");
do {
ReparentStyleContext(outOfFlow);
} while ((outOfFlow = outOfFlow->GetNextContinuation()));
}
// DO NOT verify the style tree before reparenting. The frame
// tree has already been changed, so this check would just fail.
nsStyleContext* oldContext = aFrame->StyleContext();
// XXXbz can oldContext really ever be null?
if (oldContext) {
nsRefPtr<nsStyleContext> newContext;
nsIFrame* providerFrame = aFrame->GetParentStyleContextFrame();
bool isChild = providerFrame && providerFrame->GetParent() == aFrame;
nsStyleContext* newParentContext = nullptr;
nsIFrame* providerChild = nullptr;
if (isChild) {
ReparentStyleContext(providerFrame);
newParentContext = providerFrame->StyleContext();
providerChild = providerFrame;
} else if (providerFrame) {
newParentContext = providerFrame->StyleContext();
} else {
NS_NOTREACHED("Reparenting something that has no usable parent? "
"Shouldn't happen!");
}
// XXX need to do something here to produce the correct style context for
// an IB split whose first inline part is inside a first-line frame.
// Currently the first IB anonymous block's style context takes the first
// part's style context as parent, which is wrong since first-line style
// should not apply to the anonymous block.
#ifdef DEBUG
{
// Check that our assumption that continuations of the same
// pseudo-type and with the same style context parent have the
// same style context is valid before the reresolution. (We need
// to check the pseudo-type and style context parent because of
// :first-letter and :first-line, where we create styled and
// unstyled letter/line frames distinguished by pseudo-type, and
// then need to distinguish their descendants based on having
// different parents.)
nsIFrame *nextContinuation = aFrame->GetNextContinuation();
if (nextContinuation) {
nsStyleContext *nextContinuationContext =
nextContinuation->StyleContext();
NS_ASSERTION(oldContext == nextContinuationContext ||
oldContext->GetPseudo() !=
nextContinuationContext->GetPseudo() ||
oldContext->GetParent() !=
nextContinuationContext->GetParent(),
"continuations should have the same style context");
}
}
#endif
nsIFrame *prevContinuation =
GetPrevContinuationWithPossiblySameStyle(aFrame);
nsStyleContext *prevContinuationContext;
bool copyFromContinuation =
prevContinuation &&
(prevContinuationContext = prevContinuation->StyleContext())
->GetPseudo() == oldContext->GetPseudo() &&
prevContinuationContext->GetParent() == newParentContext;
if (copyFromContinuation) {
// Just use the style context from the frame's previous
// continuation (see assertion about aFrame->GetNextContinuation()
// above, which we would have previously hit for aFrame's previous
// continuation).
newContext = prevContinuationContext;
} else {
nsIFrame* parentFrame = aFrame->GetParent();
Element* element =
ElementForStyleContext(parentFrame ? parentFrame->GetContent() : nullptr,
aFrame,
oldContext->GetPseudoType());
newContext = mStyleSet->ReparentStyleContext(oldContext,
newParentContext,
element);
}
if (newContext) {
if (newContext != oldContext) {
// We probably don't want to initiate transitions from
// ReparentStyleContext, since we call it during frame
// construction rather than in response to dynamic changes.
// Also see the comment at the start of
// nsTransitionManager::ConsiderStartingTransition.
#if 0
if (!copyFromContinuation) {
TryStartingTransition(GetPresContext(), aFrame->GetContent(),
oldContext, &newContext);
}
#endif
// Make sure to call CalcStyleDifference so that the new context ends
// up resolving all the structs the old context resolved.
DebugOnly<nsChangeHint> styleChange =
oldContext->CalcStyleDifference(newContext, nsChangeHint(0));
// The style change is always 0 because we have the same rulenode and
// CalcStyleDifference optimizes us away. That's OK, though:
// reparenting should never trigger a frame reconstruct, and whenever
// it's happening we already plan to reflow and repaint the frames.
NS_ASSERTION(!(styleChange & nsChangeHint_ReconstructFrame),
"Our frame tree is likely to be bogus!");
aFrame->SetStyleContext(newContext);
nsIFrame::ChildListIterator lists(aFrame);
for (; !lists.IsDone(); lists.Next()) {
nsFrameList::Enumerator childFrames(lists.CurrentList());
for (; !childFrames.AtEnd(); childFrames.Next()) {
nsIFrame* child = childFrames.get();
// only do frames that are in flow
if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW) &&
child != providerChild) {
#ifdef DEBUG
if (nsGkAtoms::placeholderFrame == child->GetType()) {
nsIFrame* outOfFlowFrame =
nsPlaceholderFrame::GetRealFrameForPlaceholder(child);
NS_ASSERTION(outOfFlowFrame, "no out-of-flow frame");
NS_ASSERTION(outOfFlowFrame != providerChild,
"Out of flow provider?");
}
#endif
ReparentStyleContext(child);
}
}
}
// If this frame is part of an IB split, then the style context of
// the next part of the split might be a child of our style context.
// Reparent its style context just in case one of our ancestors
// (split or not) hasn't done so already). It's not a problem to
// reparent the same frame twice because the "if (newContext !=
// oldContext)" check will prevent us from redoing work.
if ((aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) &&
!aFrame->GetPrevContinuation()) {
nsIFrame* sib = static_cast<nsIFrame*>
(aFrame->Properties().Get(nsIFrame::IBSplitSpecialSibling()));
if (sib) {
ReparentStyleContext(sib);
}
}
// do additional contexts
int32_t contextIndex = -1;
while (1) {
nsStyleContext* oldExtraContext =
aFrame->GetAdditionalStyleContext(++contextIndex);
if (oldExtraContext) {
nsRefPtr<nsStyleContext> newExtraContext;
newExtraContext = mStyleSet->ReparentStyleContext(oldExtraContext,
newContext,
nullptr);
if (newExtraContext) {
if (newExtraContext != oldExtraContext) {
// Make sure to call CalcStyleDifference so that the new
// context ends up resolving all the structs the old context
// resolved.
styleChange =
oldExtraContext->CalcStyleDifference(newExtraContext,
nsChangeHint(0));
// The style change is always 0 because we have the same
// rulenode and CalcStyleDifference optimizes us away. That's
// OK, though: reparenting should never trigger a frame
// reconstruct, and whenever it's happening we already plan to
// reflow and repaint the frames.
NS_ASSERTION(!(styleChange & nsChangeHint_ReconstructFrame),
"Our frame tree is likely to be bogus!");
}
aFrame->SetAdditionalStyleContext(contextIndex, newExtraContext);
}
}
else {
break;
}
}
#ifdef DEBUG
VerifyStyleTree(GetPresContext(), aFrame, newParentContext);
#endif
}
}
}
return NS_OK;
}
static void
CaptureChange(nsStyleContext* aOldContext, nsStyleContext* aNewContext,
nsIFrame* aFrame, nsIContent* aContent,
nsStyleChangeList* aChangeList,
/*inout*/nsChangeHint &aMinChange,
/*in*/nsChangeHint aParentHintsNotHandledForDescendants,
/*out*/nsChangeHint &aHintsNotHandledForDescendants,
nsChangeHint aChangeToAssume)
{
nsChangeHint ourChange = aOldContext->CalcStyleDifference(aNewContext,
aParentHintsNotHandledForDescendants);
NS_ASSERTION(!(ourChange & nsChangeHint_AllReflowHints) ||
(ourChange & nsChangeHint_NeedReflow),
"Reflow hint bits set without actually asking for a reflow");
// nsChangeHint_UpdateEffects is inherited, but it can be set due to changes
// in inherited properties (fill and stroke). Avoid propagating it into
// text nodes.
if ((ourChange & nsChangeHint_UpdateEffects) &&
aContent && !aContent->IsElement()) {
ourChange = NS_SubtractHint(ourChange, nsChangeHint_UpdateEffects);
}
NS_UpdateHint(ourChange, aChangeToAssume);
if (NS_UpdateHint(aMinChange, ourChange)) {
if (!(ourChange & nsChangeHint_ReconstructFrame) || aContent) {
aChangeList->AppendChange(aFrame, aContent, ourChange);
}
}
aHintsNotHandledForDescendants = NS_HintsNotHandledForDescendantsIn(ourChange);
}
/**
* Recompute style for aFrame and accumulate changes into aChangeList
* given that aMinChange is already accumulated for an ancestor.
* aParentContent is the content node used to resolve the parent style
* context. This means that, for pseudo-elements, it is the content
* that should be used for selector matching (rather than the fake
* content node attached to the frame).
*
* For aParentFrameHintsNotHandledForDescendants, see
* nsStyleContext::CalcStyleDifference.
*/
nsChangeHint
nsFrameManager::ReResolveStyleContext(nsPresContext *aPresContext,
nsIFrame *aFrame,
nsIContent *aParentContent,
nsStyleChangeList *aChangeList,
nsChangeHint aMinChange,
nsChangeHint aParentFrameHintsNotHandledForDescendants,
nsRestyleHint aRestyleHint,
RestyleTracker& aRestyleTracker,
DesiredA11yNotifications aDesiredA11yNotifications,
nsTArray<nsIContent*>& aVisibleKidsOfHiddenElement,
TreeMatchContext &aTreeMatchContext)
{
// We need to generate a new change list entry for every frame whose style
// comparision returns one of these hints. These hints don't automatically
// update all their descendant frames.
aMinChange = NS_SubtractHint(aMinChange, NS_HintsNotHandledForDescendantsIn(aMinChange));
// It would be nice if we could make stronger assertions here; they
// would let us simplify the ?: expressions below setting |content|
// and |pseudoContent| in sensible ways as well as making what
// |localContent|, |content|, and |pseudoContent| mean make more
// sense. However, we can't, because of frame trees like the one in
// https://bugzilla.mozilla.org/show_bug.cgi?id=472353#c14 . Once we
// fix bug 242277 we should be able to make this make more sense.
NS_ASSERTION(aFrame->GetContent() || !aParentContent ||
!aParentContent->GetParent(),
"frame must have content (unless at the top of the tree)");
// XXXldb get new context from prev-in-flow if possible, to avoid
// duplication. (Or should we just let |GetContext| handle that?)
// Getting the hint would be nice too, but that's harder.
// XXXbryner we may be able to avoid some of the refcounting goop here.
// We do need a reference to oldContext for the lifetime of this function, and it's possible
// that the frame has the last reference to it, so AddRef it here.
nsChangeHint assumeDifferenceHint = NS_STYLE_HINT_NONE;
// XXXbz oldContext should just be an nsRefPtr
nsStyleContext* oldContext = aFrame->StyleContext();
nsStyleSet* styleSet = aPresContext->StyleSet();
// XXXbz the nsIFrame constructor takes an nsStyleContext, so how
// could oldContext be null?
if (oldContext) {
oldContext->AddRef();
#ifdef ACCESSIBILITY
bool wasFrameVisible = nsIPresShell::IsAccessibilityActive() ?
oldContext->StyleVisibility()->IsVisible() : false;
#endif
nsIAtom* const pseudoTag = oldContext->GetPseudo();
const nsCSSPseudoElements::Type pseudoType = oldContext->GetPseudoType();
nsIContent* localContent = aFrame->GetContent();
// |content| is the node that we used for rule matching of
// normal elements (not pseudo-elements) and for which we generate
// framechange hints if we need them.
// XXXldb Why does it make sense to use aParentContent? (See
// comment above assertion at start of function.)
nsIContent* content = localContent ? localContent : aParentContent;
if (content && content->IsElement()) {
content->OwnerDoc()->FlushPendingLinkUpdates();
RestyleTracker::RestyleData restyleData;
if (aRestyleTracker.GetRestyleData(content->AsElement(), &restyleData)) {
if (NS_UpdateHint(aMinChange, restyleData.mChangeHint)) {
aChangeList->AppendChange(aFrame, content, restyleData.mChangeHint);
}
aRestyleHint = nsRestyleHint(aRestyleHint | restyleData.mRestyleHint);
}
}
nsRestyleHint childRestyleHint = aRestyleHint;
if (childRestyleHint == eRestyle_Self) {
childRestyleHint = nsRestyleHint(0);
}
nsStyleContext* parentContext;
nsIFrame* resolvedChild = nullptr;
// Get the frame providing the parent style context. If it is a
// child, then resolve the provider first.
nsIFrame* providerFrame = aFrame->GetParentStyleContextFrame();
bool isChild = providerFrame && providerFrame->GetParent() == aFrame;
if (!isChild) {
if (providerFrame)
parentContext = providerFrame->StyleContext();
else
parentContext = nullptr;
}
else {
MOZ_ASSERT(providerFrame->GetContent() == aFrame->GetContent(),
"Postcondition for GetParentStyleContextFrame() violated. "
"That means we need to add the current element to the "
"ancestor filter.");
// resolve the provider here (before aFrame below).
// assumeDifferenceHint forces the parent's change to be also
// applied to this frame, no matter what
// nsStyleContext::CalcStyleDifference says. CalcStyleDifference
// can't be trusted because it assumes any changes to the parent
// style context provider will be automatically propagated to
// the frame(s) with child style contexts.
assumeDifferenceHint = ReResolveStyleContext(aPresContext, providerFrame,
aParentContent, aChangeList,
aMinChange,
nsChangeHint_Hints_NotHandledForDescendants,
aRestyleHint,
aRestyleTracker,
aDesiredA11yNotifications,
aVisibleKidsOfHiddenElement,
aTreeMatchContext);
// The provider's new context becomes the parent context of
// aFrame's context.
parentContext = providerFrame->StyleContext();
// Set |resolvedChild| so we don't bother resolving the
// provider again.
resolvedChild = providerFrame;
}
if (providerFrame != aFrame->GetParent()) {
// We don't actually know what the parent style context's
// non-inherited hints were, so assume the worst.
aParentFrameHintsNotHandledForDescendants =
nsChangeHint_Hints_NotHandledForDescendants;
}
#ifdef DEBUG
{
// Check that our assumption that continuations of the same
// pseudo-type and with the same style context parent have the
// same style context is valid before the reresolution. (We need
// to check the pseudo-type and style context parent because of
// :first-letter and :first-line, where we create styled and
// unstyled letter/line frames distinguished by pseudo-type, and
// then need to distinguish their descendants based on having
// different parents.)
nsIFrame *nextContinuation = aFrame->GetNextContinuation();
if (nextContinuation) {
nsStyleContext *nextContinuationContext =
nextContinuation->StyleContext();
NS_ASSERTION(oldContext == nextContinuationContext ||
oldContext->GetPseudo() !=
nextContinuationContext->GetPseudo() ||
oldContext->GetParent() !=
nextContinuationContext->GetParent(),
"continuations should have the same style context");
}
// And assert the same thing for {ib} splits. See the comments in
// GetPrevContinuationWithPossiblySameStyle for an explanation of
// why we step two forward in the special sibling chain.
if ((aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) &&
!aFrame->GetPrevContinuation()) {
nsIFrame *nextIBSibling = static_cast<nsIFrame*>(
aFrame->Properties().Get(nsIFrame::IBSplitSpecialSibling()));
if (nextIBSibling) {
nextIBSibling = static_cast<nsIFrame*>(
nextIBSibling->Properties().Get(nsIFrame::IBSplitSpecialSibling()));
}
if (nextIBSibling) {
nsStyleContext *nextIBSiblingContext =
nextIBSibling->StyleContext();
NS_ASSERTION(oldContext == nextIBSiblingContext ||
oldContext->GetPseudo() !=
nextIBSiblingContext->GetPseudo() ||
oldContext->GetParent() !=
nextIBSiblingContext->GetParent(),
"continuations should have the same style context");
}
}
}
#endif
// do primary context
nsRefPtr<nsStyleContext> newContext;
nsChangeHint nonInheritedHints = nsChangeHint(0);
nsIFrame *prevContinuation =
GetPrevContinuationWithPossiblySameStyle(aFrame);
nsStyleContext *prevContinuationContext;
bool copyFromContinuation =
prevContinuation &&
(prevContinuationContext = prevContinuation->StyleContext())
->GetPseudo() == oldContext->GetPseudo() &&
prevContinuationContext->GetParent() == parentContext;
if (copyFromContinuation) {
// Just use the style context from the frame's previous
// continuation (see assertion about aFrame->GetNextContinuation()
// above, which we would have previously hit for aFrame's previous
// continuation).
newContext = prevContinuationContext;
// We don't know what changes the previous continuation had, so
// assume the worst.
nonInheritedHints = nsChangeHint_Hints_NotHandledForDescendants;
}
else if (pseudoTag == nsCSSAnonBoxes::mozNonElement) {
NS_ASSERTION(localContent,
"non pseudo-element frame without content node");
newContext = styleSet->ResolveStyleForNonElement(parentContext);
}
else if (!aRestyleHint && !prevContinuation) {
// Unfortunately, if prevContinuation is non-null then we may have
// already stolen the restyle tracker entry for this element while
// processing prevContinuation. So we don't know whether aRestyleHint
// should really be 0 here or whether it should be eRestyle_Self. Be
// pessimistic and force an actual reresolve in that situation. The good
// news is that in the common case when prevContinuation is non-null we
// just used prevContinuationContext anyway and aren't reaching this code
// to start with.
newContext =
styleSet->ReparentStyleContext(oldContext, parentContext,
ElementForStyleContext(aParentContent,
aFrame,
pseudoType));
} else if (pseudoType == nsCSSPseudoElements::ePseudo_AnonBox) {
newContext = styleSet->ResolveAnonymousBoxStyle(pseudoTag,
parentContext);
}
else {
Element* element = ElementForStyleContext(aParentContent,
aFrame,
pseudoType);
if (pseudoTag) {
if (pseudoTag == nsCSSPseudoElements::before ||
pseudoTag == nsCSSPseudoElements::after) {
// XXX what other pseudos do we need to treat like this?
newContext = styleSet->ProbePseudoElementStyle(element,
pseudoType,
parentContext,
aTreeMatchContext);
if (!newContext) {
// This pseudo should no longer exist; gotta reframe
NS_UpdateHint(aMinChange, nsChangeHint_ReconstructFrame);
aChangeList->AppendChange(aFrame, element,
nsChangeHint_ReconstructFrame);
// We're reframing anyway; just keep the same context
newContext = oldContext;
}
} else {
// Don't expect XUL tree stuff here, since it needs a comparator and
// all.
NS_ASSERTION(pseudoType <
nsCSSPseudoElements::ePseudo_PseudoElementCount,
"Unexpected pseudo type");
newContext = styleSet->ResolvePseudoElementStyle(element,
pseudoType,
parentContext);
}
}
else {
NS_ASSERTION(localContent,
"non pseudo-element frame without content node");
newContext = styleSet->ResolveStyleFor(element, parentContext,
aTreeMatchContext);
}
}
NS_ASSERTION(newContext, "failed to get new style context");
if (newContext) {
if (!parentContext) {
if (oldContext->RuleNode() == newContext->RuleNode() &&
oldContext->IsLinkContext() == newContext->IsLinkContext() &&
oldContext->RelevantLinkVisited() ==
newContext->RelevantLinkVisited()) {
// We're the root of the style context tree and the new style
// context returned has the same rule node. This means that
// we can use FindChildWithRules to keep a lot of the old
// style contexts around. However, we need to start from the
// same root.
newContext = oldContext;
}
}
if (newContext != oldContext) {
if (!copyFromContinuation) {
TryStartingTransition(aPresContext, aFrame->GetContent(),
oldContext, &newContext);
}
CaptureChange(oldContext, newContext, aFrame, content, aChangeList,
aMinChange, aParentFrameHintsNotHandledForDescendants,
nonInheritedHints, assumeDifferenceHint);
if (!(aMinChange & nsChangeHint_ReconstructFrame)) {
// if frame gets regenerated, let it keep old context
aFrame->SetStyleContext(newContext);
}
}
oldContext->Release();
}
else {
NS_ERROR("resolve style context failed");
newContext = oldContext; // new context failed, recover...
}
// do additional contexts
// XXXbz might be able to avoid selector matching here in some
// cases; won't worry about it for now.
int32_t contextIndex = -1;
while (1 == 1) {
nsStyleContext* oldExtraContext = nullptr;
oldExtraContext = aFrame->GetAdditionalStyleContext(++contextIndex);
if (oldExtraContext) {
nsRefPtr<nsStyleContext> newExtraContext;
nsIAtom* const extraPseudoTag = oldExtraContext->GetPseudo();
const nsCSSPseudoElements::Type extraPseudoType =
oldExtraContext->GetPseudoType();
NS_ASSERTION(extraPseudoTag &&
extraPseudoTag != nsCSSAnonBoxes::mozNonElement,
"extra style context is not pseudo element");
if (extraPseudoType == nsCSSPseudoElements::ePseudo_AnonBox) {
newExtraContext = styleSet->ResolveAnonymousBoxStyle(extraPseudoTag,
newContext);
}
else {
// Don't expect XUL tree stuff here, since it needs a comparator and
// all.
NS_ASSERTION(extraPseudoType <
nsCSSPseudoElements::ePseudo_PseudoElementCount,
"Unexpected type");
newExtraContext = styleSet->ResolvePseudoElementStyle(content->AsElement(),
extraPseudoType,
newContext);
}
if (newExtraContext) {
if (oldExtraContext != newExtraContext) {
nsChangeHint extraHintsNotHandledForDescendants = nsChangeHint(0);
CaptureChange(oldExtraContext, newExtraContext, aFrame, content,
aChangeList, aMinChange,
aParentFrameHintsNotHandledForDescendants,
extraHintsNotHandledForDescendants,
assumeDifferenceHint);
NS_UpdateHint(nonInheritedHints, extraHintsNotHandledForDescendants);
if (!(aMinChange & nsChangeHint_ReconstructFrame)) {
aFrame->SetAdditionalStyleContext(contextIndex, newExtraContext);
}
}
}
}
else {
break;
}
}
// now look for undisplayed child content and pseudos
// When the root element is display:none, we still construct *some*
// frames that have the root element as their mContent, down to the
// DocElementContainingBlock.
bool checkUndisplayed;
nsIContent *undisplayedParent;
if (pseudoTag) {
checkUndisplayed = aFrame == mPresShell->FrameConstructor()->
GetDocElementContainingBlock();
undisplayedParent = nullptr;
} else {
checkUndisplayed = !!localContent;
undisplayedParent = localContent;
}
if (checkUndisplayed && mUndisplayedMap) {
UndisplayedNode* undisplayed =
mUndisplayedMap->GetFirstNode(undisplayedParent);
for (TreeMatchContext::AutoAncestorPusher
pushAncestor(undisplayed, aTreeMatchContext,
undisplayedParent ? undisplayedParent->AsElement()
: nullptr);
undisplayed; undisplayed = undisplayed->mNext) {
NS_ASSERTION(undisplayedParent ||
undisplayed->mContent ==
mPresShell->GetDocument()->GetRootElement(),
"undisplayed node child of null must be root");
NS_ASSERTION(!undisplayed->mStyle->GetPseudo(),
"Shouldn't have random pseudo style contexts in the "
"undisplayed map");
nsRestyleHint thisChildHint = childRestyleHint;
RestyleTracker::RestyleData undisplayedRestyleData;
if (aRestyleTracker.GetRestyleData(undisplayed->mContent->AsElement(),
&undisplayedRestyleData)) {
thisChildHint =
nsRestyleHint(thisChildHint | undisplayedRestyleData.mRestyleHint);
}
nsRefPtr<nsStyleContext> undisplayedContext;
if (thisChildHint) {
undisplayedContext =
styleSet->ResolveStyleFor(undisplayed->mContent->AsElement(),
newContext,
aTreeMatchContext);
} else {
undisplayedContext =
styleSet->ReparentStyleContext(undisplayed->mStyle, newContext,
undisplayed->mContent->AsElement());
}
if (undisplayedContext) {
const nsStyleDisplay* display = undisplayedContext->StyleDisplay();
if (display->mDisplay != NS_STYLE_DISPLAY_NONE) {
NS_ASSERTION(undisplayed->mContent,
"Must have undisplayed content");
aChangeList->AppendChange(nullptr, undisplayed->mContent,
NS_STYLE_HINT_FRAMECHANGE);
// The node should be removed from the undisplayed map when
// we reframe it.
} else {
// update the undisplayed node with the new context
undisplayed->mStyle = undisplayedContext;
}
}
}
}
// Check whether we might need to create a new ::before frame.
// There's no need to do this if we're planning to reframe already
// or if we're not forcing restyles on kids.
if (!(aMinChange & nsChangeHint_ReconstructFrame) &&
childRestyleHint) {
// Make sure not to do this for pseudo-frames or frames that
// can't have generated content.
if (!pseudoTag &&
((aFrame->GetStateBits() & NS_FRAME_MAY_HAVE_GENERATED_CONTENT) ||
// Our content insertion frame might have gotten flagged
(aFrame->GetContentInsertionFrame()->GetStateBits() &
NS_FRAME_MAY_HAVE_GENERATED_CONTENT))) {
// Check for a new :before pseudo and an existing :before
// frame, but only if the frame is the first continuation.
nsIFrame* prevContinuation = aFrame->GetPrevContinuation();
if (!prevContinuation) {
// Checking for a :before frame is cheaper than getting the
// :before style context.
if (!nsLayoutUtils::GetBeforeFrame(aFrame) &&
nsLayoutUtils::HasPseudoStyle(localContent, newContext,
nsCSSPseudoElements::ePseudo_before,
aPresContext)) {
// Have to create the new :before frame
NS_UpdateHint(aMinChange, nsChangeHint_ReconstructFrame);
aChangeList->AppendChange(aFrame, content,
nsChangeHint_ReconstructFrame);
}
}
}
}
// Check whether we might need to create a new ::after frame.
// There's no need to do this if we're planning to reframe already
// or if we're not forcing restyles on kids.
if (!(aMinChange & nsChangeHint_ReconstructFrame) &&
childRestyleHint) {
// Make sure not to do this for pseudo-frames or frames that
// can't have generated content.
if (!pseudoTag &&
((aFrame->GetStateBits() & NS_FRAME_MAY_HAVE_GENERATED_CONTENT) ||
// Our content insertion frame might have gotten flagged
(aFrame->GetContentInsertionFrame()->GetStateBits() &
NS_FRAME_MAY_HAVE_GENERATED_CONTENT))) {
// Check for new :after content, but only if the frame is the
// last continuation.
nsIFrame* nextContinuation = aFrame->GetNextContinuation();
if (!nextContinuation) {
// Getting the :after frame is more expensive than getting the pseudo
// context, so get the pseudo context first.
if (nsLayoutUtils::HasPseudoStyle(localContent, newContext,
nsCSSPseudoElements::ePseudo_after,
aPresContext) &&
!nsLayoutUtils::GetAfterFrame(aFrame)) {
// have to create the new :after frame
NS_UpdateHint(aMinChange, nsChangeHint_ReconstructFrame);
aChangeList->AppendChange(aFrame, content,
nsChangeHint_ReconstructFrame);
}
}
}
}
if (!(aMinChange & nsChangeHint_ReconstructFrame)) {
DesiredA11yNotifications kidsDesiredA11yNotification =
aDesiredA11yNotifications;
#ifdef ACCESSIBILITY
A11yNotificationType ourA11yNotification = eDontNotify;
// Notify a11y for primary frame only if it's a root frame of visibility
// changes or its parent frame was hidden while it stays visible and
// it is not inside a {ib} split or is the first frame of {ib} split.
if (nsIPresShell::IsAccessibilityActive() &&
!aFrame->GetPrevContinuation() &&
!nsLayoutUtils::FrameIsNonFirstInIBSplit(aFrame)) {
if (aDesiredA11yNotifications == eSendAllNotifications) {
bool isFrameVisible = newContext->StyleVisibility()->IsVisible();
if (isFrameVisible != wasFrameVisible) {
if (isFrameVisible) {
// Notify a11y the element (perhaps with its children) was shown.
// We don't fall into this case if this element gets or stays shown
// while its parent becomes hidden.
kidsDesiredA11yNotification = eSkipNotifications;
ourA11yNotification = eNotifyShown;
} else {
// The element is being hidden; its children may stay visible, or
// become visible after being hidden previously. If we'll find
// visible children then we should notify a11y about that as if
// they were inserted into tree. Notify a11y this element was
// hidden.
kidsDesiredA11yNotification = eNotifyIfShown;
ourA11yNotification = eNotifyHidden;
}
}
} else if (aDesiredA11yNotifications == eNotifyIfShown &&
newContext->StyleVisibility()->IsVisible()) {
// Notify a11y that element stayed visible while its parent was
// hidden.
aVisibleKidsOfHiddenElement.AppendElement(aFrame->GetContent());
kidsDesiredA11yNotification = eSkipNotifications;
}
}
#endif
// There is no need to waste time crawling into a frame's children on a frame change.
// The act of reconstructing frames will force new style contexts to be resolved on all
// of this frame's descendants anyway, so we want to avoid wasting time processing
// style contexts that we're just going to throw away anyway. - dwh
// now do children
nsIFrame::ChildListIterator lists(aFrame);
for (TreeMatchContext::AutoAncestorPusher
pushAncestor(!lists.IsDone(),
aTreeMatchContext,
content && content->IsElement() ? content->AsElement()
: nullptr);
!lists.IsDone(); lists.Next()) {
nsFrameList::Enumerator childFrames(lists.CurrentList());
for (; !childFrames.AtEnd(); childFrames.Next()) {
nsIFrame* child = childFrames.get();
if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW)) {
// only do frames that are in flow
if (nsGkAtoms::placeholderFrame == child->GetType()) { // placeholder
// get out of flow frame and recur there
nsIFrame* outOfFlowFrame =
nsPlaceholderFrame::GetRealFrameForPlaceholder(child);
NS_ASSERTION(outOfFlowFrame, "no out-of-flow frame");
NS_ASSERTION(outOfFlowFrame != resolvedChild,
"out-of-flow frame not a true descendant");
// Note that the out-of-flow may not be a geometric descendant of
// the frame where we started the reresolve. Therefore, even if
// aMinChange already includes nsChangeHint_AllReflowHints we don't
// want to pass that on to the out-of-flow reresolve, since that
// can lead to the out-of-flow not getting reflowed when it should
// be (eg a reresolve starting at <body> that involves reflowing
// the <body> would miss reflowing fixed-pos nodes that also need
// reflow). In the cases when the out-of-flow _is_ a geometric
// descendant of a frame we already have a reflow hint for,
// reflow coalescing should keep us from doing the work twice.
// |nsFrame::GetParentStyleContextFrame| checks being out
// of flow so that this works correctly.
do {
ReResolveStyleContext(aPresContext, outOfFlowFrame,
content, aChangeList,
NS_SubtractHint(aMinChange,
nsChangeHint_AllReflowHints),
nonInheritedHints,
childRestyleHint,
aRestyleTracker,
kidsDesiredA11yNotification,
aVisibleKidsOfHiddenElement,
aTreeMatchContext);
} while ((outOfFlowFrame = outOfFlowFrame->GetNextContinuation()));
// reresolve placeholder's context under the same parent
// as the out-of-flow frame
ReResolveStyleContext(aPresContext, child, content,
aChangeList, aMinChange,
nonInheritedHints,
childRestyleHint,
aRestyleTracker,
kidsDesiredA11yNotification,
aVisibleKidsOfHiddenElement,
aTreeMatchContext);
}
else { // regular child frame
if (child != resolvedChild) {
ReResolveStyleContext(aPresContext, child, content,
aChangeList, aMinChange,
nonInheritedHints,
childRestyleHint,
aRestyleTracker,
kidsDesiredA11yNotification,
aVisibleKidsOfHiddenElement,
aTreeMatchContext);
} else {
NOISY_TRACE_FRAME("child frame already resolved as descendant, skipping",aFrame);
}
}
}
}
}
// XXX need to do overflow frames???
#ifdef ACCESSIBILITY
// Send notifications about visibility changes.
if (ourA11yNotification == eNotifyShown) {
nsAccessibilityService* accService = nsIPresShell::AccService();
if (accService) {
nsIPresShell* presShell = aFrame->PresContext()->GetPresShell();
nsIContent* content = aFrame->GetContent();
accService->ContentRangeInserted(presShell, content->GetParent(),
content,
content->GetNextSibling());
}
} else if (ourA11yNotification == eNotifyHidden) {
nsAccessibilityService* accService = nsIPresShell::AccService();
if (accService) {
nsIPresShell* presShell = aFrame->PresContext()->GetPresShell();
nsIContent* content = aFrame->GetContent();
accService->ContentRemoved(presShell, content->GetParent(), content);
// Process children staying shown.
uint32_t visibleContentCount = aVisibleKidsOfHiddenElement.Length();
for (uint32_t idx = 0; idx < visibleContentCount; idx++) {
nsIContent* content = aVisibleKidsOfHiddenElement[idx];
accService->ContentRangeInserted(presShell, content->GetParent(),
content, content->GetNextSibling());
}
aVisibleKidsOfHiddenElement.Clear();
}
}
#endif
}
}
return aMinChange;
}
void
nsFrameManager::ComputeStyleChangeFor(nsIFrame *aFrame,
nsStyleChangeList *aChangeList,
nsChangeHint aMinChange,
RestyleTracker& aRestyleTracker,
bool aRestyleDescendants)
{
SAMPLE_LABEL("CSS", "ComputeStyleChangeFor");
nsIContent *content = aFrame->GetContent();
if (aMinChange) {
aChangeList->AppendChange(aFrame, content, aMinChange);
}
nsChangeHint topLevelChange = aMinChange;
nsIFrame* frame = aFrame;
nsIFrame* frame2 = aFrame;
NS_ASSERTION(!frame->GetPrevContinuation(), "must start with the first in flow");
// We want to start with this frame and walk all its next-in-flows,
// as well as all its special siblings and their next-in-flows,
// reresolving style on all the frames we encounter in this walk.
FramePropertyTable *propTable = GetPresContext()->PropertyTable();
TreeMatchContext treeMatchContext(true,
nsRuleWalker::eRelevantLinkUnvisited,
mPresShell->GetDocument());
nsIContent *parent = content ? content->GetParent() : nullptr;
Element *parentElement =
parent && parent->IsElement() ? parent->AsElement() : nullptr;
treeMatchContext.InitAncestors(parentElement);
nsTArray<nsIContent*> visibleKidsOfHiddenElement;
do {
// Outer loop over special siblings
do {
// Inner loop over next-in-flows of the current frame
nsChangeHint frameChange =
ReResolveStyleContext(GetPresContext(), frame, nullptr,
aChangeList, topLevelChange, nsChangeHint(0),
aRestyleDescendants ?
eRestyle_Subtree : eRestyle_Self,
aRestyleTracker,
eSendAllNotifications,
visibleKidsOfHiddenElement,
treeMatchContext);
NS_UpdateHint(topLevelChange, frameChange);
if (topLevelChange & nsChangeHint_ReconstructFrame) {
// If it's going to cause a framechange, then don't bother
// with the continuations or special siblings since they'll be
// clobbered by the frame reconstruct anyway.
NS_ASSERTION(!frame->GetPrevContinuation(),
"continuing frame had more severe impact than first-in-flow");
return;
}
frame = frame->GetNextContinuation();
} while (frame);
// Might we have special siblings?
if (!(frame2->GetStateBits() & NS_FRAME_IS_SPECIAL)) {
// nothing more to do here
return;
}
frame2 = static_cast<nsIFrame*>
(propTable->Get(frame2, nsIFrame::IBSplitSpecialSibling()));
frame = frame2;
} while (frame2);
}
// Capture state for a given frame.
// Accept a content id here, in some cases we may not have content (scroll position)
void
nsFrameManager::CaptureFrameStateFor(nsIFrame* aFrame,
nsILayoutHistoryState* aState)
{
if (!aFrame || !aState) {
NS_WARNING("null frame, or state");
return;
}
// Only capture state for stateful frames
nsIStatefulFrame* statefulFrame = do_QueryFrame(aFrame);
if (!statefulFrame) {
return;
}
// Capture the state, exit early if we get null (nothing to save)
nsAutoPtr<nsPresState> frameState;
nsresult rv = statefulFrame->SaveState(getter_Transfers(frameState));
if (!frameState) {
return;
}
// Generate the hash key to store the state under
// Exit early if we get empty key
nsAutoCString stateKey;
nsIContent* content = aFrame->GetContent();
nsIDocument* doc = content ? content->GetCurrentDoc() : nullptr;
rv = nsContentUtils::GenerateStateKey(content, doc, stateKey);
if(NS_FAILED(rv) || stateKey.IsEmpty()) {
return;
}
// Store the state
rv = aState->AddState(stateKey, frameState);
if (NS_SUCCEEDED(rv)) {
// aState owns frameState now.
frameState.forget();
}
}
void
nsFrameManager::CaptureFrameState(nsIFrame* aFrame,
nsILayoutHistoryState* aState)
{
NS_PRECONDITION(nullptr != aFrame && nullptr != aState, "null parameters passed in");
CaptureFrameStateFor(aFrame, aState);
// Now capture state recursively for the frame hierarchy rooted at aFrame
nsIFrame::ChildListIterator lists(aFrame);
for (; !lists.IsDone(); lists.Next()) {
nsFrameList::Enumerator childFrames(lists.CurrentList());
for (; !childFrames.AtEnd(); childFrames.Next()) {
nsIFrame* child = childFrames.get();
if (child->GetStateBits() & NS_FRAME_OUT_OF_FLOW) {
// We'll pick it up when we get to its placeholder
continue;
}
// Make sure to walk through placeholders as needed, so that we
// save state for out-of-flows which may not be our descendants
// themselves but whose placeholders are our descendants.
CaptureFrameState(nsPlaceholderFrame::GetRealFrameFor(child), aState);
}
}
}
// Restore state for a given frame.
// Accept a content id here, in some cases we may not have content (scroll position)
void
nsFrameManager::RestoreFrameStateFor(nsIFrame* aFrame,
nsILayoutHistoryState* aState)
{
if (!aFrame || !aState) {
NS_WARNING("null frame or state");
return;
}
// Only restore state for stateful frames
nsIStatefulFrame* statefulFrame = do_QueryFrame(aFrame);
if (!statefulFrame) {
return;
}
// Generate the hash key the state was stored under
// Exit early if we get empty key
nsIContent* content = aFrame->GetContent();
// If we don't have content, we can't generate a hash
// key and there's probably no state information for us.
if (!content) {
return;
}
nsAutoCString stateKey;
nsIDocument* doc = content->GetCurrentDoc();
nsresult rv = nsContentUtils::GenerateStateKey(content, doc, stateKey);
if (NS_FAILED(rv) || stateKey.IsEmpty()) {
return;
}
// Get the state from the hash
nsPresState *frameState;
rv = aState->GetState(stateKey, &frameState);
if (!frameState) {
return;
}
// Restore it
rv = statefulFrame->RestoreState(frameState);
if (NS_FAILED(rv)) {
return;
}
// If we restore ok, remove the state from the state table
aState->RemoveState(stateKey);
}
void
nsFrameManager::RestoreFrameState(nsIFrame* aFrame,
nsILayoutHistoryState* aState)
{
NS_PRECONDITION(nullptr != aFrame && nullptr != aState, "null parameters passed in");
RestoreFrameStateFor(aFrame, aState);
// Now restore state recursively for the frame hierarchy rooted at aFrame
nsIFrame::ChildListIterator lists(aFrame);
for (; !lists.IsDone(); lists.Next()) {
nsFrameList::Enumerator childFrames(lists.CurrentList());
for (; !childFrames.AtEnd(); childFrames.Next()) {
RestoreFrameState(childFrames.get(), aState);
}
}
}
//----------------------------------------------------------------------
static PLHashNumber
HashKey(void* key)
{
return NS_PTR_TO_INT32(key);
}
static int
CompareKeys(void* key1, void* key2)
{
return key1 == key2;
}
//----------------------------------------------------------------------
nsFrameManagerBase::UndisplayedMap::UndisplayedMap(uint32_t aNumBuckets)
{
MOZ_COUNT_CTOR(nsFrameManagerBase::UndisplayedMap);
mTable = PL_NewHashTable(aNumBuckets, (PLHashFunction)HashKey,
(PLHashComparator)CompareKeys,
(PLHashComparator)nullptr,
nullptr, nullptr);
mLastLookup = nullptr;
}
nsFrameManagerBase::UndisplayedMap::~UndisplayedMap(void)
{
MOZ_COUNT_DTOR(nsFrameManagerBase::UndisplayedMap);
Clear();
PL_HashTableDestroy(mTable);
}
PLHashEntry**
nsFrameManagerBase::UndisplayedMap::GetEntryFor(nsIContent* aParentContent)
{
if (mLastLookup && (aParentContent == (*mLastLookup)->key)) {
return mLastLookup;
}
PLHashNumber hashCode = NS_PTR_TO_INT32(aParentContent);
PLHashEntry** entry = PL_HashTableRawLookup(mTable, hashCode, aParentContent);
if (*entry) {
mLastLookup = entry;
}
return entry;
}
UndisplayedNode*
nsFrameManagerBase::UndisplayedMap::GetFirstNode(nsIContent* aParentContent)
{
PLHashEntry** entry = GetEntryFor(aParentContent);
if (*entry) {
return (UndisplayedNode*)((*entry)->value);
}
return nullptr;
}
void
nsFrameManagerBase::UndisplayedMap::AppendNodeFor(UndisplayedNode* aNode,
nsIContent* aParentContent)
{
PLHashEntry** entry = GetEntryFor(aParentContent);
if (*entry) {
UndisplayedNode* node = (UndisplayedNode*)((*entry)->value);
while (node->mNext) {
if (node->mContent == aNode->mContent) {
// We actually need to check this in optimized builds because
// there are some callers that do this. See bug 118014, bug
// 136704, etc.
NS_NOTREACHED("node in map twice");
delete aNode;
return;
}
node = node->mNext;
}
node->mNext = aNode;
}
else {
PLHashNumber hashCode = NS_PTR_TO_INT32(aParentContent);
PL_HashTableRawAdd(mTable, entry, hashCode, aParentContent, aNode);
mLastLookup = nullptr; // hashtable may have shifted bucket out from under us
}
}
nsresult
nsFrameManagerBase::UndisplayedMap::AddNodeFor(nsIContent* aParentContent,
nsIContent* aChild,
nsStyleContext* aStyle)
{
UndisplayedNode* node = new UndisplayedNode(aChild, aStyle);
AppendNodeFor(node, aParentContent);
return NS_OK;
}
void
nsFrameManagerBase::UndisplayedMap::RemoveNodeFor(nsIContent* aParentContent,
UndisplayedNode* aNode)
{
PLHashEntry** entry = GetEntryFor(aParentContent);
NS_ASSERTION(*entry, "content not in map");
if (*entry) {
if ((UndisplayedNode*)((*entry)->value) == aNode) { // first node
if (aNode->mNext) {
(*entry)->value = aNode->mNext;
aNode->mNext = nullptr;
}
else {
PL_HashTableRawRemove(mTable, entry, *entry);
mLastLookup = nullptr; // hashtable may have shifted bucket out from under us
}
}
else {
UndisplayedNode* node = (UndisplayedNode*)((*entry)->value);
while (node->mNext) {
if (node->mNext == aNode) {
node->mNext = aNode->mNext;
aNode->mNext = nullptr;
break;
}
node = node->mNext;
}
}
}
delete aNode;
}
void
nsFrameManagerBase::UndisplayedMap::RemoveNodesFor(nsIContent* aParentContent)
{
PLHashEntry** entry = GetEntryFor(aParentContent);
NS_ASSERTION(entry, "content not in map");
if (*entry) {
UndisplayedNode* node = (UndisplayedNode*)((*entry)->value);
NS_ASSERTION(node, "null node for non-null entry in UndisplayedMap");
delete node;
PL_HashTableRawRemove(mTable, entry, *entry);
mLastLookup = nullptr; // hashtable may have shifted bucket out from under us
}
}
static int
RemoveUndisplayedEntry(PLHashEntry* he, int i, void* arg)
{
UndisplayedNode* node = (UndisplayedNode*)(he->value);
delete node;
// Remove and free this entry and continue enumerating
return HT_ENUMERATE_REMOVE | HT_ENUMERATE_NEXT;
}
void
nsFrameManagerBase::UndisplayedMap::Clear(void)
{
mLastLookup = nullptr;
PL_HashTableEnumerateEntries(mTable, RemoveUndisplayedEntry, 0);
}
uint32_t nsFrameManagerBase::sGlobalGenerationNumber;