forked from mirrors/gecko-dev
0a20585745
MozReview-Commit-ID: 2FXGFEkpIKE --HG-- extra : rebase_source : 280c85f0e53e6426289580a345685898888ed266
1100 lines
46 KiB
C++
1100 lines
46 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/*
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* a node in the lexicographic tree of rules that match an element,
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* responsible for converting the rules' information into computed style
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*/
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#ifndef nsRuleNode_h___
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#define nsRuleNode_h___
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#include "mozilla/ArenaObjectID.h"
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#include "mozilla/LinkedList.h"
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#include "mozilla/PodOperations.h"
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#include "mozilla/RangedArray.h"
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#include "mozilla/RuleNodeCacheConditions.h"
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#include "mozilla/LookAndFeel.h"
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#include "mozilla/SheetType.h"
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#include "nsPresContext.h"
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#include "nsStyleStruct.h"
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class nsCSSPropertyIDSet;
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class nsCSSValue;
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class nsFontMetrics;
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class nsIStyleRule;
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class nsStyleCoord;
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struct nsCSSRect;
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struct nsCSSValueList;
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struct nsCSSValuePairList;
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struct nsRuleData;
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namespace mozilla {
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class GeckoStyleContext;
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} // namespace mozilla
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struct nsInheritedStyleData
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{
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mozilla::RangedArray<void*,
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nsStyleStructID_Inherited_Start,
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nsStyleStructID_Inherited_Count> mStyleStructs;
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void* operator new(size_t sz, nsPresContext* aContext) {
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return aContext->PresShell()->
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AllocateByObjectID(mozilla::eArenaObjectID_nsInheritedStyleData, sz);
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}
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void DestroyStructs(uint64_t aBits, nsPresContext* aContext) {
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#define STYLE_STRUCT_INHERITED(name, checkdata_cb) \
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void *name##Data = mStyleStructs[eStyleStruct_##name]; \
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if (name##Data && !(aBits & NS_STYLE_INHERIT_BIT(name))) \
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static_cast<nsStyle##name*>(name##Data)->Destroy(aContext);
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#define STYLE_STRUCT_RESET(name, checkdata_cb)
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#include "nsStyleStructList.h"
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#undef STYLE_STRUCT_INHERITED
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#undef STYLE_STRUCT_RESET
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}
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void Destroy(uint64_t aBits, nsPresContext* aContext) {
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DestroyStructs(aBits, aContext);
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aContext->PresShell()->
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FreeByObjectID(mozilla::eArenaObjectID_nsInheritedStyleData, this);
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}
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nsInheritedStyleData() {
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for (nsStyleStructID i = nsStyleStructID_Inherited_Start;
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i < nsStyleStructID_Inherited_Start + nsStyleStructID_Inherited_Count;
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i = nsStyleStructID(i + 1)) {
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mStyleStructs[i] = nullptr;
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}
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}
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};
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struct nsResetStyleData
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{
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mozilla::RangedArray<void*,
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nsStyleStructID_Reset_Start,
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nsStyleStructID_Reset_Count> mStyleStructs;
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nsResetStyleData()
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{
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for (nsStyleStructID i = nsStyleStructID_Reset_Start;
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i < nsStyleStructID_Reset_Start + nsStyleStructID_Reset_Count;
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i = nsStyleStructID(i + 1)) {
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mStyleStructs[i] = nullptr;
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}
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}
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void* operator new(size_t sz, nsPresContext* aContext) {
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return aContext->PresShell()->
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AllocateByObjectID(mozilla::eArenaObjectID_nsResetStyleData, sz);
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}
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void Destroy(uint64_t aBits, nsPresContext* aContext) {
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#define STYLE_STRUCT_RESET(name, checkdata_cb) \
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void *name##Data = mStyleStructs[eStyleStruct_##name]; \
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if (name##Data && !(aBits & NS_STYLE_INHERIT_BIT(name))) \
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static_cast<nsStyle##name*>(name##Data)->Destroy(aContext);
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#define STYLE_STRUCT_INHERITED(name, checkdata_cb)
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#include "nsStyleStructList.h"
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#undef STYLE_STRUCT_RESET
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#undef STYLE_STRUCT_INHERITED
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aContext->PresShell()->
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FreeByObjectID(mozilla::eArenaObjectID_nsResetStyleData, this);
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}
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};
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struct nsConditionalResetStyleData
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{
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static uint32_t GetBitForSID(const nsStyleStructID aSID) {
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return 1 << aSID;
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}
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struct Entry
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{
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Entry(const mozilla::RuleNodeCacheConditions& aConditions,
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void* aStyleStruct,
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Entry* aNext)
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: mConditions(aConditions), mStyleStruct(aStyleStruct), mNext(aNext) {}
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void* operator new(size_t sz, nsPresContext* aContext) {
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return aContext->PresShell()->AllocateByObjectID(
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mozilla::eArenaObjectID_nsConditionalResetStyleDataEntry, sz);
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}
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const mozilla::RuleNodeCacheConditions mConditions;
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void* const mStyleStruct;
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Entry* const mNext;
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};
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// Each entry is either a pointer to a style struct or a
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// pointer to an Entry object. A bit in mConditionalBits
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// means that it is an Entry.
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mozilla::RangedArray<void*,
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nsStyleStructID_Reset_Start,
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nsStyleStructID_Reset_Count> mEntries;
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uint32_t mConditionalBits;
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nsConditionalResetStyleData()
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{
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for (nsStyleStructID i = nsStyleStructID_Reset_Start;
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i < nsStyleStructID_Reset_Start + nsStyleStructID_Reset_Count;
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i = nsStyleStructID(i + 1)) {
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mEntries[i] = nullptr;
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}
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mConditionalBits = 0;
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}
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void* operator new(size_t sz, nsPresContext* aContext) {
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return aContext->PresShell()->AllocateByObjectID(
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mozilla::eArenaObjectID_nsConditionalResetStyleData, sz);
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}
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void* GetStyleData(nsStyleStructID aSID) const {
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if (mConditionalBits & GetBitForSID(aSID)) {
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return nullptr;
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}
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return mEntries[aSID];
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}
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void* GetStyleData(nsStyleStructID aSID,
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mozilla::GeckoStyleContext* aStyleContext,
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bool aCanComputeData) const {
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if (!(mConditionalBits & GetBitForSID(aSID))) {
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return mEntries[aSID];
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}
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if (!aCanComputeData) {
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// If aCanComputeData is false, then any previously-computed data
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// would have been cached on the style context. Therefore it's
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// unnecessary to check the conditional data. It's also
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// incorrect, because calling e->mConditions.Matches() below could
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// cause additional structs to be computed, which is incorrect
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// during CalcStyleDifference.
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return nullptr;
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}
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return GetConditionalStyleData(aSID, aStyleContext);
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}
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private:
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// non-inline helper for GetStyleData
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void* GetConditionalStyleData(nsStyleStructID aSID,
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mozilla::GeckoStyleContext* aStyleContext) const;
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public:
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void SetStyleData(nsStyleStructID aSID, void* aStyleStruct) {
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MOZ_ASSERT(!(mConditionalBits & GetBitForSID(aSID)),
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"rule node should not have unconditional and conditional style "
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"data for a given struct");
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mConditionalBits &= ~GetBitForSID(aSID);
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mEntries[aSID] = aStyleStruct;
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}
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void SetStyleData(nsStyleStructID aSID,
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nsPresContext* aPresContext,
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void* aStyleStruct,
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const mozilla::RuleNodeCacheConditions& aConditions) {
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if (!(mConditionalBits & GetBitForSID(aSID))) {
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MOZ_ASSERT(!mEntries[aSID],
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"rule node should not have unconditional and conditional "
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"style data for a given struct");
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mEntries[aSID] = nullptr;
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}
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MOZ_ASSERT(aConditions.CacheableWithDependencies(),
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"don't call SetStyleData with a cache key that has no "
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"conditions or is uncacheable");
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#ifdef DEBUG
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for (Entry* e = static_cast<Entry*>(mEntries[aSID]); e; e = e->mNext) {
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NS_WARNING_ASSERTION(e->mConditions != aConditions,
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"wasteful to have duplicate conditional style data");
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}
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#endif
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mConditionalBits |= GetBitForSID(aSID);
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mEntries[aSID] =
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new (aPresContext) Entry(aConditions, aStyleStruct,
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static_cast<Entry*>(mEntries[aSID]));
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}
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void Destroy(uint64_t aBits, nsPresContext* aContext) {
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#define STYLE_STRUCT_RESET(name, checkdata_cb) \
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void* name##Ptr = mEntries[eStyleStruct_##name]; \
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if (name##Ptr) { \
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if (!(mConditionalBits & NS_STYLE_INHERIT_BIT(name))) { \
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if (!(aBits & NS_STYLE_INHERIT_BIT(name))) { \
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static_cast<nsStyle##name*>(name##Ptr)->Destroy(aContext); \
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} \
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} else { \
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Entry* e = static_cast<Entry*>(name##Ptr); \
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MOZ_ASSERT(e, "if mConditionalBits bit is set, we must have at least " \
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"one conditional style struct"); \
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do { \
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static_cast<nsStyle##name*>(e->mStyleStruct)->Destroy(aContext); \
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Entry* next = e->mNext; \
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aContext->PresShell()->FreeByObjectID( \
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mozilla::eArenaObjectID_nsConditionalResetStyleDataEntry, e); \
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e = next; \
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} while (e); \
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} \
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}
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#define STYLE_STRUCT_INHERITED(name, checkdata_cb)
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#include "nsStyleStructList.h"
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#undef STYLE_STRUCT_RESET
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#undef STYLE_STRUCT_INHERITED
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aContext->PresShell()->FreeByObjectID(
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mozilla::eArenaObjectID_nsConditionalResetStyleData, this);
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}
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};
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struct nsCachedStyleData
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{
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nsInheritedStyleData* mInheritedData;
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nsConditionalResetStyleData* mResetData;
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static bool IsReset(const nsStyleStructID aSID) {
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MOZ_ASSERT(0 <= aSID && aSID < nsStyleStructID_Length,
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"must be an inherited or reset SID");
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return nsStyleStructID_Reset_Start <= aSID;
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}
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static bool IsInherited(const nsStyleStructID aSID) {
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return !IsReset(aSID);
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}
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static uint32_t GetBitForSID(const nsStyleStructID aSID) {
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return nsConditionalResetStyleData::GetBitForSID(aSID);
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}
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void* NS_FASTCALL GetStyleData(const nsStyleStructID aSID) {
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if (IsReset(aSID)) {
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if (mResetData) {
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return mResetData->GetStyleData(aSID);
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}
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} else {
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if (mInheritedData) {
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return mInheritedData->mStyleStructs[aSID];
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}
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}
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return nullptr;
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}
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void* NS_FASTCALL GetStyleData(const nsStyleStructID aSID,
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mozilla::GeckoStyleContext* aStyleContext,
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bool aCanComputeData) {
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if (IsReset(aSID)) {
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if (mResetData) {
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return mResetData->GetStyleData(aSID, aStyleContext, aCanComputeData);
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}
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} else {
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if (mInheritedData) {
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return mInheritedData->mStyleStructs[aSID];
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}
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}
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return nullptr;
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}
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void NS_FASTCALL SetStyleData(const nsStyleStructID aSID,
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nsPresContext *aPresContext, void *aData) {
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if (IsReset(aSID)) {
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if (!mResetData) {
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mResetData = new (aPresContext) nsConditionalResetStyleData;
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}
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mResetData->SetStyleData(aSID, aData);
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} else {
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if (!mInheritedData) {
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mInheritedData = new (aPresContext) nsInheritedStyleData;
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}
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mInheritedData->mStyleStructs[aSID] = aData;
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}
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}
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// Typesafe and faster versions of the above
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#define STYLE_STRUCT_INHERITED(name_, checkdata_cb_) \
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nsStyle##name_ * NS_FASTCALL GetStyle##name_ () { \
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return mInheritedData ? static_cast<nsStyle##name_*>( \
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mInheritedData->mStyleStructs[eStyleStruct_##name_]) : nullptr; \
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}
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#define STYLE_STRUCT_RESET(name_, checkdata_cb_) \
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nsStyle##name_ * NS_FASTCALL GetStyle##name_ (mozilla::GeckoStyleContext* aContext, \
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bool aCanComputeData) { \
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return mResetData ? static_cast<nsStyle##name_*>( \
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mResetData->GetStyleData(eStyleStruct_##name_, aContext, \
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aCanComputeData)) \
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: nullptr; \
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}
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#include "nsStyleStructList.h"
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#undef STYLE_STRUCT_RESET
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#undef STYLE_STRUCT_INHERITED
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void Destroy(uint64_t aBits, nsPresContext* aContext) {
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if (mResetData)
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mResetData->Destroy(aBits, aContext);
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if (mInheritedData)
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mInheritedData->Destroy(aBits, aContext);
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mResetData = nullptr;
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mInheritedData = nullptr;
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}
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nsCachedStyleData() :mInheritedData(nullptr), mResetData(nullptr) {}
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~nsCachedStyleData() {}
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};
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/**
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* nsRuleNode is a node in a lexicographic tree (the "rule tree")
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* indexed by style rules (implementations of nsIStyleRule).
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*
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* The rule tree is owned by the nsStyleSet and is destroyed when the
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* presentation of the document goes away. Its entries are reference-
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* counted, with strong references held by child nodes, style structs
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* and (for the root), the style set. Rule nodes are not immediately
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* destroyed when their reference-count drops to zero, but are instead
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* destroyed during a GC sweep.
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*
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* An mozilla::GeckoStyleContext, which represents the computed style data for an
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* element, points to an nsRuleNode. The path from the root of the rule
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* tree to the mozilla::GeckoStyleContext's mRuleNode gives the list of the rules
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* matched, from least important in the cascading order to most
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* important in the cascading order.
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*
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* The reason for using a lexicographic tree is that it allows for
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* sharing of style data, which saves both memory (for storing the
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* computed style data) and time (for computing them). This sharing
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* depends on the computed style data being stored in structs (nsStyle*)
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* that contain only properties that are inherited by default
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* ("inherited structs") or structs that contain only properties that
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* are not inherited by default ("reset structs"). The optimization
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* depends on the normal case being that style rules specify relatively
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* few properties and even that elements generally have relatively few
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* properties specified. This allows sharing in the following ways:
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* 1. [mainly reset structs] When a style data struct will contain the
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* same computed value for any elements that match the same set of
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* rules (common for reset structs), it can be stored on the
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* nsRuleNode instead of on the mozilla::GeckoStyleContext.
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* 2. [only? reset structs] When (1) occurs, and an nsRuleNode doesn't
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* have any rules that change the values in the struct, the
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* nsRuleNode can share that struct with its parent nsRuleNode.
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* 3. [mainly inherited structs] When an element doesn't match any
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* rules that change the value of a property (or, in the edge case,
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* when all the values specified are 'inherit'), the mozilla::GeckoStyleContext
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* can use the same nsStyle* struct as its parent mozilla::GeckoStyleContext.
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*
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* Since the data represented by an nsIStyleRule are immutable, the data
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* represented by an nsRuleNode are also immutable.
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*/
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enum nsFontSizeType {
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eFontSize_HTML = 1,
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eFontSize_CSS = 2
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};
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// Note: This LinkedListElement is used for storing unused nodes in the
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// linked list on nsStyleSet. We use mNextSibling for the singly-linked
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// sibling list.
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class nsRuleNode : public mozilla::LinkedListElement<nsRuleNode> {
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public:
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enum RuleDetail {
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eRuleNone, // No props have been specified at all.
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eRulePartialReset, // At least one prop with a non-"inherit" value
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// has been specified. No props have been
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// specified with an "inherit" value. At least
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// one prop remains unspecified.
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eRulePartialMixed, // At least one prop with a non-"inherit" value
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// has been specified. Some props may also have
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// been specified with an "inherit" value. At
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// least one prop remains unspecified.
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eRulePartialInherited, // Only props with "inherit" values have
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// have been specified. At least one prop
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// remains unspecified.
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eRuleFullReset, // All props have been specified. None has an
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// "inherit" value.
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eRuleFullMixed, // All props have been specified. At least one has
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// a non-"inherit" value.
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eRuleFullInherited // All props have been specified with "inherit"
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// values.
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};
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private:
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nsPresContext* const mPresContext; // Our pres context.
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const RefPtr<nsRuleNode> mParent; // A pointer to the parent node in the tree.
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// This enables us to walk backwards from the
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// most specific rule matched to the least
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// specific rule (which is the optimal order to
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// use for lookups of style properties.
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const nsCOMPtr<nsIStyleRule> mRule; // A pointer to our specific rule.
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nsRuleNode* mNextSibling; // This value should be used only by the
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// parent, since the parent may store
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// children in a hash, which means this
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// pointer is not meaningful. Order of
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// siblings is also not meaningful.
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struct Key {
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nsIStyleRule* mRule;
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mozilla::SheetType mLevel;
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bool mIsImportantRule;
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Key(nsIStyleRule* aRule, mozilla::SheetType aLevel, bool aIsImportantRule)
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: mRule(aRule), mLevel(aLevel), mIsImportantRule(aIsImportantRule)
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{}
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bool operator==(const Key& aOther) const
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{
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return mRule == aOther.mRule &&
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mLevel == aOther.mLevel &&
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mIsImportantRule == aOther.mIsImportantRule;
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}
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bool operator!=(const Key& aOther) const
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{
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return !(*this == aOther);
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}
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};
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static PLDHashNumber
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ChildrenHashHashKey(const void *aKey);
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static bool
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ChildrenHashMatchEntry(const PLDHashEntryHdr *aHdr, const void *aKey);
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static const PLDHashTableOps ChildrenHashOps;
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Key GetKey() const {
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return Key(mRule, GetLevel(), IsImportantRule());
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}
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// The children of this node are stored in either a hashtable or list
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// that maps from rules to our nsRuleNode children. When matching
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// rules, we use this mapping to transition from node to node
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// (constructing new nodes as needed to flesh out the tree).
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union {
|
|
void* asVoid;
|
|
nsRuleNode* asList;
|
|
PLDHashTable* asHash;
|
|
} mChildren; // Accessed only through the methods below.
|
|
|
|
enum {
|
|
kTypeMask = 0x1,
|
|
kListType = 0x0,
|
|
kHashType = 0x1
|
|
};
|
|
enum {
|
|
// Maximum to have in a list before converting to a hashtable.
|
|
// XXX Need to optimize this.
|
|
kMaxChildrenInList = 32
|
|
};
|
|
|
|
bool HaveChildren() const {
|
|
return mChildren.asVoid != nullptr;
|
|
}
|
|
bool ChildrenAreHashed() {
|
|
return (intptr_t(mChildren.asVoid) & kTypeMask) == kHashType;
|
|
}
|
|
nsRuleNode* ChildrenList() {
|
|
return mChildren.asList;
|
|
}
|
|
nsRuleNode** ChildrenListPtr() {
|
|
return &mChildren.asList;
|
|
}
|
|
PLDHashTable* ChildrenHash() {
|
|
return (PLDHashTable*) (intptr_t(mChildren.asHash) & ~intptr_t(kTypeMask));
|
|
}
|
|
void SetChildrenList(nsRuleNode *aList) {
|
|
NS_ASSERTION(!(intptr_t(aList) & kTypeMask),
|
|
"pointer not 2-byte aligned");
|
|
mChildren.asList = aList;
|
|
}
|
|
void SetChildrenHash(PLDHashTable *aHashtable) {
|
|
NS_ASSERTION(!(intptr_t(aHashtable) & kTypeMask),
|
|
"pointer not 2-byte aligned");
|
|
mChildren.asHash = (PLDHashTable*)(intptr_t(aHashtable) | kHashType);
|
|
}
|
|
void ConvertChildrenToHash(int32_t aNumKids);
|
|
|
|
void RemoveChild(nsRuleNode* aNode);
|
|
|
|
nsCachedStyleData mStyleData; // Any data we cached on the rule node.
|
|
|
|
uint32_t mDependentBits; // Used to cache the fact that we can look up
|
|
// cached data under a parent rule.
|
|
|
|
uint32_t mNoneBits; // Used to cache the fact that the branch to this
|
|
// node specifies no non-inherited data for a
|
|
// given struct type. (This usually implies that
|
|
// the entire branch specifies no non-inherited
|
|
// data, although not necessarily, if a
|
|
// non-inherited value is overridden by an
|
|
// explicit 'inherit' value.) For example, if an
|
|
// entire rule branch specifies no color
|
|
// information, then a bit will be set along every
|
|
// rule node on that branch, so that you can break
|
|
// out of the rule tree early and just inherit
|
|
// from the parent style context. The presence of
|
|
// this bit means we should just get inherited
|
|
// data from the parent style context, and it is
|
|
// never used for reset structs since their
|
|
// Compute*Data functions don't initialize from
|
|
// inherited data.
|
|
|
|
// Reference count. Style contexts hold strong references to their rule node,
|
|
// and rule nodes hold strong references to their parent.
|
|
//
|
|
// When the refcount drops to zero, we don't necessarily free the node.
|
|
// Instead, we notify the style set, which performs periodic sweeps.
|
|
uint32_t mRefCnt;
|
|
|
|
public:
|
|
// Infallible overloaded new operator that allocates from a presShell arena.
|
|
void* operator new(size_t sz, nsPresContext* aContext);
|
|
void Destroy();
|
|
|
|
// Implemented in nsStyleSet.h, since it needs to know about nsStyleSet.
|
|
inline void AddRef();
|
|
|
|
// Implemented in nsStyleSet.h, since it needs to know about nsStyleSet.
|
|
inline void Release();
|
|
|
|
protected:
|
|
void PropagateDependentBit(nsStyleStructID aSID, nsRuleNode* aHighestNode,
|
|
void* aStruct);
|
|
void PropagateNoneBit(uint32_t aBit, nsRuleNode* aHighestNode);
|
|
static void PropagateGrandancestorBit(mozilla::GeckoStyleContext* aContext,
|
|
mozilla::GeckoStyleContext* aContextInheritedFrom);
|
|
|
|
const void* SetDefaultOnRoot(const nsStyleStructID aSID,
|
|
mozilla::GeckoStyleContext* aContext);
|
|
|
|
/**
|
|
* Resolves any property values in aRuleData for a given style struct that
|
|
* have eCSSUnit_TokenStream values, by resolving them against the computed
|
|
* variable values on the style context and re-parsing the property.
|
|
*
|
|
* @return Whether any properties with eCSSUnit_TokenStream values were
|
|
* encountered.
|
|
*/
|
|
static bool ResolveVariableReferences(const nsStyleStructID aSID,
|
|
nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext);
|
|
|
|
const void*
|
|
WalkRuleTree(const nsStyleStructID aSID, mozilla::GeckoStyleContext* aContext);
|
|
|
|
const void*
|
|
ComputeDisplayData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeVisibilityData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeFontData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeColorData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeBackgroundData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeMarginData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeBorderData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputePaddingData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeOutlineData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeListData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputePositionData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeTableData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeTableBorderData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeContentData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeTextData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeTextResetData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeUserInterfaceData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext,
|
|
nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeUIResetData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeXULData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeColumnData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeSVGData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeSVGResetData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeVariablesData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
const void*
|
|
ComputeEffectsData(void* aStartStruct,
|
|
const nsRuleData* aRuleData,
|
|
mozilla::GeckoStyleContext* aContext, nsRuleNode* aHighestNode,
|
|
RuleDetail aRuleDetail,
|
|
const mozilla::RuleNodeCacheConditions aConditions);
|
|
|
|
// helpers for |ComputeFontData| that need access to |mNoneBits|:
|
|
static void SetFontSize(nsPresContext* aPresContext,
|
|
mozilla::GeckoStyleContext* aContext,
|
|
const nsRuleData* aRuleData,
|
|
const nsStyleFont* aFont,
|
|
const nsStyleFont* aParentFont,
|
|
nscoord* aSize,
|
|
const nsFont& aSystemFont,
|
|
nscoord aParentSize,
|
|
nscoord aScriptLevelAdjustedParentSize,
|
|
bool aUsedStartStruct,
|
|
bool aAtRoot,
|
|
mozilla::RuleNodeCacheConditions& aConditions);
|
|
|
|
static void SetFont(nsPresContext* aPresContext,
|
|
mozilla::GeckoStyleContext* aContext,
|
|
uint8_t aGenericFontID,
|
|
const nsRuleData* aRuleData,
|
|
const nsStyleFont* aParentFont,
|
|
nsStyleFont* aFont,
|
|
bool aStartStruct,
|
|
mozilla::RuleNodeCacheConditions& aConditions);
|
|
|
|
static void SetGenericFont(nsPresContext* aPresContext,
|
|
mozilla::GeckoStyleContext* aContext,
|
|
uint8_t aGenericFontID,
|
|
nsStyleFont* aFont);
|
|
|
|
inline RuleDetail CheckSpecifiedProperties(const nsStyleStructID aSID,
|
|
const nsRuleData* aRuleData);
|
|
|
|
private:
|
|
nsRuleNode(nsPresContext* aPresContext, nsRuleNode* aParent,
|
|
nsIStyleRule* aRule, mozilla::SheetType aLevel, bool aIsImportant);
|
|
~nsRuleNode();
|
|
|
|
public:
|
|
// This is infallible; it will never return nullptr.
|
|
static already_AddRefed<nsRuleNode> CreateRootNode(nsPresContext* aPresContext);
|
|
|
|
static void EnsureBlockDisplay(mozilla::StyleDisplay& display,
|
|
bool aConvertListItem = false);
|
|
static void EnsureInlineDisplay(mozilla::StyleDisplay& display);
|
|
|
|
static already_AddRefed<nsFontMetrics> GetMetricsFor(nsPresContext* aPresContext,
|
|
nsStyleContext* aStyleContext,
|
|
const nsStyleFont* aStyleFont,
|
|
nscoord aFontSize,
|
|
bool aUseUserFontSet);
|
|
|
|
// Transition never returns null; on out of memory it'll just return |this|.
|
|
nsRuleNode* Transition(nsIStyleRule* aRule, mozilla::SheetType aLevel,
|
|
bool aIsImportantRule);
|
|
nsRuleNode* GetParent() const { return mParent; }
|
|
bool IsRoot() const { return mParent == nullptr; }
|
|
|
|
// Return the root of the rule tree that this rule node is in.
|
|
nsRuleNode* RuleTree();
|
|
const nsRuleNode* RuleTree() const {
|
|
return const_cast<nsRuleNode*>(this)->RuleTree();
|
|
}
|
|
|
|
mozilla::SheetType GetLevel() const {
|
|
NS_ASSERTION(!IsRoot(), "can't call on root");
|
|
return mozilla::SheetType(
|
|
(mDependentBits & NS_RULE_NODE_LEVEL_MASK) >>
|
|
NS_RULE_NODE_LEVEL_SHIFT);
|
|
}
|
|
bool IsImportantRule() const {
|
|
NS_ASSERTION(!IsRoot(), "can't call on root");
|
|
return (mDependentBits & NS_RULE_NODE_IS_IMPORTANT) != 0;
|
|
}
|
|
|
|
/**
|
|
* Has this rule node at some time in its lifetime been the mRuleNode
|
|
* of some style context (as opposed to only being the ancestor of
|
|
* some style context's mRuleNode)?
|
|
*/
|
|
void SetUsedDirectly();
|
|
bool IsUsedDirectly() const {
|
|
return (mDependentBits & NS_RULE_NODE_USED_DIRECTLY) != 0;
|
|
}
|
|
|
|
/**
|
|
* Is the mRule of this rule node an AnimValuesStyleRule?
|
|
*/
|
|
void SetIsAnimationRule() {
|
|
MOZ_ASSERT(!HaveChildren() ||
|
|
(mDependentBits & NS_RULE_NODE_IS_ANIMATION_RULE),
|
|
"SetIsAnimationRule must only set the IS_ANIMATION_RULE bit "
|
|
"before the rule node has children");
|
|
mDependentBits |= NS_RULE_NODE_IS_ANIMATION_RULE;
|
|
mNoneBits |= NS_RULE_NODE_HAS_ANIMATION_DATA;
|
|
}
|
|
bool IsAnimationRule() const {
|
|
return (mDependentBits & NS_RULE_NODE_IS_ANIMATION_RULE) != 0;
|
|
}
|
|
|
|
/**
|
|
* Is the mRule of this rule node or any of its ancestors an
|
|
* AnimValuesStyleRule?
|
|
*/
|
|
bool HasAnimationData() const {
|
|
return (mNoneBits & NS_RULE_NODE_HAS_ANIMATION_DATA) != 0;
|
|
}
|
|
|
|
// NOTE: Does not |AddRef|. Null only for the root.
|
|
nsIStyleRule* GetRule() const { return mRule; }
|
|
// NOTE: Does not |AddRef|. Never null.
|
|
nsPresContext* PresContext() const { return mPresContext; }
|
|
|
|
const void* GetStyleData(nsStyleStructID aSID,
|
|
mozilla::GeckoStyleContext* aContext,
|
|
bool aComputeData);
|
|
|
|
void GetDiscretelyAnimatedCSSValue(nsCSSPropertyID aProperty,
|
|
nsCSSValue* aValue);
|
|
|
|
// See comments in GetStyleData for an explanation of what the
|
|
// code below does.
|
|
#define STYLE_STRUCT_INHERITED(name_, checkdata_cb_) \
|
|
template<bool aComputeData> \
|
|
const nsStyle##name_* \
|
|
GetStyle##name_(mozilla::GeckoStyleContext* aContext, uint64_t& aContextStyleBits) \
|
|
{ \
|
|
NS_ASSERTION(IsUsedDirectly(), \
|
|
"if we ever call this on rule nodes that aren't used " \
|
|
"directly, we should adjust handling of mDependentBits " \
|
|
"in some way."); \
|
|
MOZ_ASSERT(!ContextHasCachedData(aContext, eStyleStruct_##name_), \
|
|
"style context should not have cached data for struct"); \
|
|
\
|
|
const nsStyle##name_ *data; \
|
|
\
|
|
/* Never use cached data for animated style inside a pseudo-element; */ \
|
|
/* see comment on cacheability in AnimValuesStyleRule::MapRuleInfoInto */ \
|
|
if (!(HasAnimationData() && ParentHasPseudoElementData(aContext))) { \
|
|
data = mStyleData.GetStyle##name_(); \
|
|
if (data != nullptr) { \
|
|
/* For inherited structs, mark the struct (which will be set on */ \
|
|
/* the context by our caller) as not being owned by the context. */ \
|
|
/* Normally this would be aContext->AddStyleBit(), but aContext is */ \
|
|
/* an incomplete type here, so we work around that with a param. */ \
|
|
aContextStyleBits |= NS_STYLE_INHERIT_BIT(name_); \
|
|
/* Our caller will cache the data on the style context. */ \
|
|
return data; \
|
|
} \
|
|
} \
|
|
\
|
|
if (!aComputeData) \
|
|
return nullptr; \
|
|
\
|
|
data = static_cast<const nsStyle##name_ *> \
|
|
(WalkRuleTree(eStyleStruct_##name_, aContext)); \
|
|
\
|
|
MOZ_ASSERT(data, "should have aborted on out-of-memory"); \
|
|
return data; \
|
|
}
|
|
|
|
#define STYLE_STRUCT_RESET(name_, checkdata_cb_) \
|
|
template<bool aComputeData> \
|
|
const nsStyle##name_* \
|
|
GetStyle##name_(mozilla::GeckoStyleContext* aContext) \
|
|
{ \
|
|
NS_ASSERTION(IsUsedDirectly(), \
|
|
"if we ever call this on rule nodes that aren't used " \
|
|
"directly, we should adjust handling of mDependentBits " \
|
|
"in some way."); \
|
|
MOZ_ASSERT(!ContextHasCachedData(aContext, eStyleStruct_##name_), \
|
|
"style context should not have cached data for struct"); \
|
|
\
|
|
const nsStyle##name_ *data; \
|
|
\
|
|
/* Never use cached data for animated style inside a pseudo-element; */ \
|
|
/* see comment on cacheability in AnimValuesStyleRule::MapRuleInfoInto */ \
|
|
if (!(HasAnimationData() && ParentHasPseudoElementData(aContext))) { \
|
|
data = mStyleData.GetStyle##name_(aContext, aComputeData); \
|
|
if (MOZ_LIKELY(data != nullptr)) { \
|
|
if (HasAnimationData()) { \
|
|
/* If we have animation data, the struct should be cached on the */ \
|
|
/* style context so that we can peek the struct. */ \
|
|
/* See comment in AnimValuesStyleRule::MapRuleInfoInto. */ \
|
|
StoreStyleOnContext(aContext, \
|
|
eStyleStruct_##name_, \
|
|
const_cast<nsStyle##name_*>(data)); \
|
|
} \
|
|
return data; \
|
|
} \
|
|
} \
|
|
\
|
|
if (!aComputeData) \
|
|
return nullptr; \
|
|
\
|
|
data = static_cast<const nsStyle##name_ *> \
|
|
(WalkRuleTree(eStyleStruct_##name_, aContext)); \
|
|
\
|
|
MOZ_ASSERT(data, "should have aborted on out-of-memory"); \
|
|
return data; \
|
|
}
|
|
|
|
#include "nsStyleStructList.h"
|
|
|
|
#undef STYLE_STRUCT_RESET
|
|
#undef STYLE_STRUCT_INHERITED
|
|
|
|
static bool
|
|
HasAuthorSpecifiedRules(mozilla::GeckoStyleContext* aStyleContext,
|
|
uint32_t ruleTypeMask,
|
|
bool aAuthorColorsAllowed);
|
|
|
|
/**
|
|
* Fill in to aPropertiesOverridden all of the properties in aProperties
|
|
* that, for this rule node, have a declaration that is higher than the
|
|
* animation level in the CSS Cascade.
|
|
*/
|
|
static void
|
|
ComputePropertiesOverridingAnimation(
|
|
const nsTArray<nsCSSPropertyID>& aProperties,
|
|
mozilla::GeckoStyleContext* aStyleContext,
|
|
nsCSSPropertyIDSet& aPropertiesOverridden);
|
|
|
|
// Expose this so media queries can use it
|
|
static nscoord CalcLengthWithInitialFont(nsPresContext* aPresContext,
|
|
const nsCSSValue& aValue);
|
|
|
|
// Expose this so nsTransformFunctions can use it.
|
|
//
|
|
// FIXME(emilio): This can enter here with a Servo style context, which will
|
|
// mostly be fine except for our handling of rem units, I think.
|
|
//
|
|
// Ditto in SpecifiedCalcToComputedCalc.
|
|
static nscoord CalcLength(const nsCSSValue& aValue,
|
|
nsStyleContext* aStyleContext,
|
|
nsPresContext* aPresContext,
|
|
mozilla::RuleNodeCacheConditions& aConditions);
|
|
|
|
struct ComputedCalc {
|
|
nscoord mLength;
|
|
float mPercent;
|
|
|
|
ComputedCalc() {}
|
|
|
|
ComputedCalc(nscoord aLength, float aPercent)
|
|
: mLength(aLength), mPercent(aPercent) {}
|
|
};
|
|
static ComputedCalc
|
|
SpecifiedCalcToComputedCalc(const nsCSSValue& aValue,
|
|
nsStyleContext* aStyleContext,
|
|
nsPresContext* aPresContext,
|
|
mozilla::RuleNodeCacheConditions& aConditions);
|
|
|
|
// Return whether the rule tree for which this node is the root has
|
|
// cached data such that we need to do dynamic change handling for
|
|
// changes that change the results of media queries or require
|
|
// rebuilding all style data.
|
|
bool TreeHasCachedData() const {
|
|
NS_ASSERTION(IsRoot(), "should only be called on root of rule tree");
|
|
return HaveChildren() || mStyleData.mInheritedData || mStyleData.mResetData;
|
|
}
|
|
|
|
// Note that this will return false if we have cached conditional
|
|
// style structs.
|
|
bool NodeHasCachedUnconditionalData(const nsStyleStructID aSID) {
|
|
return !!mStyleData.GetStyleData(aSID);
|
|
}
|
|
|
|
static nscoord CalcFontPointSize(int32_t aHTMLSize, int32_t aBasePointSize,
|
|
nsPresContext* aPresContext,
|
|
nsFontSizeType aFontSizeType = eFontSize_HTML);
|
|
|
|
/**
|
|
* @param aValue The color value, returned from nsCSSParser::ParseColorString
|
|
* @param aPresContext Presentation context whose preferences are used
|
|
* for certain enumerated colors
|
|
* @param aStyleContext Style context whose color is used for 'currentColor'
|
|
*
|
|
* @note aPresContext and aStyleContext may be null, but in that case, fully
|
|
* opaque black will be returned for the values that rely on these
|
|
* objects to compute the color. (For example, -moz-hyperlinktext.)
|
|
*
|
|
* @return false if we fail to extract a color; this will not happen if both
|
|
* aPresContext and aStyleContext are non-null
|
|
*/
|
|
static bool ComputeColor(const nsCSSValue& aValue,
|
|
nsPresContext* aPresContext,
|
|
nsStyleContext* aStyleContext,
|
|
nscolor& aResult);
|
|
|
|
static bool ParentHasPseudoElementData(mozilla::GeckoStyleContext* aContext);
|
|
|
|
static void ComputeTimingFunction(const nsCSSValue& aValue,
|
|
nsTimingFunction& aResult);
|
|
|
|
private:
|
|
#ifdef DEBUG
|
|
// non-inline helper function to allow assertions without incomplete
|
|
// type errors
|
|
bool ContextHasCachedData(mozilla::GeckoStyleContext* aContext, nsStyleStructID aSID);
|
|
#endif
|
|
|
|
// Store style struct on the style context and tell the style context
|
|
// that it doesn't own the data
|
|
static void StoreStyleOnContext(mozilla::GeckoStyleContext* aContext,
|
|
nsStyleStructID aSID,
|
|
void* aStruct);
|
|
};
|
|
|
|
/**
|
|
* We allocate arrays of CSS values with alloca. (These arrays are a
|
|
* fixed size per style struct, but we don't want to waste the
|
|
* allocation and construction/destruction costs of the big structs when
|
|
* we're handling much smaller ones.) Since the lifetime of an alloca
|
|
* allocation is the life of the calling function, the caller must call
|
|
* alloca. However, to ensure that constructors and destructors are
|
|
* balanced, we do the constructor and destructor calling from this RAII
|
|
* class, AutoCSSValueArray.
|
|
*/
|
|
struct AutoCSSValueArray
|
|
{
|
|
/**
|
|
* aStorage must be the result of alloca(aCount * sizeof(nsCSSValue))
|
|
*/
|
|
AutoCSSValueArray(void* aStorage, size_t aCount);
|
|
|
|
~AutoCSSValueArray();
|
|
|
|
nsCSSValue* get() { return mArray; }
|
|
|
|
private:
|
|
nsCSSValue *mArray;
|
|
size_t mCount;
|
|
};
|
|
|
|
#endif
|