/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ // vim:cindent:tabstop=2:expandtab:shiftwidth=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/. */ /* * style rule processor for CSS style sheets, responsible for selector * matching and cascading */ #define PL_ARENA_CONST_ALIGN_MASK 7 // We want page-sized arenas so there's no fragmentation involved. // Including plarena.h must come first to avoid it being included by some // header file thereby making PL_ARENA_CONST_ALIGN_MASK ineffective. #define NS_CASCADEENUMDATA_ARENA_BLOCK_SIZE (4096) #include "plarena.h" #include "nsAutoPtr.h" #include "nsCSSRuleProcessor.h" #include "nsRuleProcessorData.h" #include <algorithm> #include "nsIAtom.h" #include "PLDHashTable.h" #include "nsICSSPseudoComparator.h" #include "mozilla/MemoryReporting.h" #include "mozilla/css/StyleRule.h" #include "mozilla/css/GroupRule.h" #include "nsIDocument.h" #include "nsPresContext.h" #include "nsGkAtoms.h" #include "nsUnicharUtils.h" #include "nsError.h" #include "nsRuleWalker.h" #include "nsCSSPseudoClasses.h" #include "nsCSSPseudoElements.h" #include "nsIContent.h" #include "nsCOMPtr.h" #include "nsHashKeys.h" #include "nsStyleUtil.h" #include "nsQuickSort.h" #include "nsAttrValue.h" #include "nsAttrValueInlines.h" #include "nsAttrName.h" #include "nsTArray.h" #include "nsContentUtils.h" #include "nsIMediaList.h" #include "nsCSSRules.h" #include "nsStyleSet.h" #include "mozilla/dom/Element.h" #include "nsNthIndexCache.h" #include "mozilla/ArrayUtils.h" #include "mozilla/EventStates.h" #include "mozilla/Preferences.h" #include "mozilla/LookAndFeel.h" #include "mozilla/Likely.h" #include "mozilla/OperatorNewExtensions.h" #include "mozilla/TypedEnumBits.h" #include "RuleProcessorCache.h" #include "nsIDOMMutationEvent.h" #include "nsIMozBrowserFrame.h" using namespace mozilla; using namespace mozilla::dom; #define VISITED_PSEUDO_PREF "layout.css.visited_links_enabled" static bool gSupportVisitedPseudo = true; static nsTArray< nsCOMPtr<nsIAtom> >* sSystemMetrics = 0; #ifdef XP_WIN uint8_t nsCSSRuleProcessor::sWinThemeId = LookAndFeel::eWindowsTheme_Generic; #endif /** * A struct representing a given CSS rule and a particular selector * from that rule's selector list. */ struct RuleSelectorPair { RuleSelectorPair(css::StyleRule* aRule, nsCSSSelector* aSelector) : mRule(aRule), mSelector(aSelector) {} // If this class ever grows a destructor, deal with // PerWeightDataListItem appropriately. css::StyleRule* mRule; nsCSSSelector* mSelector; // which of |mRule|'s selectors }; #define NS_IS_ANCESTOR_OPERATOR(ch) \ ((ch) == char16_t(' ') || (ch) == char16_t('>')) /** * A struct representing a particular rule in an ordered list of rules * (the ordering depending on the weight of mSelector and the order of * our rules to start with). */ struct RuleValue : RuleSelectorPair { enum { eMaxAncestorHashes = 4 }; RuleValue(const RuleSelectorPair& aRuleSelectorPair, int32_t aIndex, bool aQuirksMode) : RuleSelectorPair(aRuleSelectorPair), mIndex(aIndex) { CollectAncestorHashes(aQuirksMode); } int32_t mIndex; // High index means high weight/order. uint32_t mAncestorSelectorHashes[eMaxAncestorHashes]; private: void CollectAncestorHashes(bool aQuirksMode) { // Collect up our mAncestorSelectorHashes. It's not clear whether it's // better to stop once we've found eMaxAncestorHashes of them or to keep // going and preferentially collect information from selectors higher up the // chain... Let's do the former for now. size_t hashIndex = 0; for (nsCSSSelector* sel = mSelector->mNext; sel; sel = sel->mNext) { if (!NS_IS_ANCESTOR_OPERATOR(sel->mOperator)) { // |sel| is going to select something that's not actually one of our // ancestors, so don't add it to mAncestorSelectorHashes. But keep // going, because it'll select a sibling of one of our ancestors, so its // ancestors would be our ancestors too. continue; } // Now sel is supposed to select one of our ancestors. Grab // whatever info we can from it into mAncestorSelectorHashes. // But in qurks mode, don't grab IDs and classes because those // need to be matched case-insensitively. if (!aQuirksMode) { nsAtomList* ids = sel->mIDList; while (ids) { mAncestorSelectorHashes[hashIndex++] = ids->mAtom->hash(); if (hashIndex == eMaxAncestorHashes) { return; } ids = ids->mNext; } nsAtomList* classes = sel->mClassList; while (classes) { mAncestorSelectorHashes[hashIndex++] = classes->mAtom->hash(); if (hashIndex == eMaxAncestorHashes) { return; } classes = classes->mNext; } } // Only put in the tag name if it's all-lowercase. Otherwise we run into // trouble because we may test the wrong one of mLowercaseTag and // mCasedTag against the filter. if (sel->mLowercaseTag && sel->mCasedTag == sel->mLowercaseTag) { mAncestorSelectorHashes[hashIndex++] = sel->mLowercaseTag->hash(); if (hashIndex == eMaxAncestorHashes) { return; } } } while (hashIndex != eMaxAncestorHashes) { mAncestorSelectorHashes[hashIndex++] = 0; } } }; // ------------------------------ // Rule hash table // // Uses any of the sets of ops below. struct RuleHashTableEntry : public PLDHashEntryHdr { // If you add members that have heap allocated memory be sure to change the // logic in SizeOfRuleHashTable(). // Auto length 1, because we always have at least one entry in mRules. AutoTArray<RuleValue, 1> mRules; }; struct RuleHashTagTableEntry : public RuleHashTableEntry { // If you add members that have heap allocated memory be sure to change the // logic in RuleHash::SizeOf{In,Ex}cludingThis. nsCOMPtr<nsIAtom> mTag; }; static PLDHashNumber RuleHash_CIHashKey(const void *key) { nsIAtom *atom = const_cast<nsIAtom*>(static_cast<const nsIAtom*>(key)); nsAutoString str; atom->ToString(str); nsContentUtils::ASCIIToLower(str); return HashString(str); } static inline nsCSSSelector* SubjectSelectorForRuleHash(const PLDHashEntryHdr *hdr) { auto entry = static_cast<const RuleHashTableEntry*>(hdr); nsCSSSelector* selector = entry->mRules[0].mSelector; if (selector->IsPseudoElement()) { selector = selector->mNext; } return selector; } static inline bool CIMatchAtoms(const void* key, nsIAtom *entry_atom) { auto match_atom = const_cast<nsIAtom*>(static_cast<const nsIAtom*>(key)); // Check for case-sensitive match first. if (match_atom == entry_atom) { return true; } // Use EqualsIgnoreASCIICase instead of full on unicode case conversion // in order to save on performance. This is only used in quirks mode // anyway. return nsContentUtils::EqualsIgnoreASCIICase(nsDependentAtomString(entry_atom), nsDependentAtomString(match_atom)); } static inline bool CSMatchAtoms(const void* key, nsIAtom *entry_atom) { auto match_atom = const_cast<nsIAtom*>(static_cast<const nsIAtom*>(key)); return match_atom == entry_atom; } static bool RuleHash_ClassCIMatchEntry(const PLDHashEntryHdr *hdr, const void *key) { return CIMatchAtoms(key, SubjectSelectorForRuleHash(hdr)->mClassList->mAtom); } static bool RuleHash_IdCIMatchEntry(const PLDHashEntryHdr *hdr, const void *key) { return CIMatchAtoms(key, SubjectSelectorForRuleHash(hdr)->mIDList->mAtom); } static bool RuleHash_ClassCSMatchEntry(const PLDHashEntryHdr *hdr, const void *key) { return CSMatchAtoms(key, SubjectSelectorForRuleHash(hdr)->mClassList->mAtom); } static bool RuleHash_IdCSMatchEntry(const PLDHashEntryHdr *hdr, const void *key) { return CSMatchAtoms(key, SubjectSelectorForRuleHash(hdr)->mIDList->mAtom); } static void RuleHash_InitEntry(PLDHashEntryHdr *hdr, const void *key) { RuleHashTableEntry* entry = static_cast<RuleHashTableEntry*>(hdr); new (KnownNotNull, entry) RuleHashTableEntry(); } static void RuleHash_ClearEntry(PLDHashTable *table, PLDHashEntryHdr *hdr) { RuleHashTableEntry* entry = static_cast<RuleHashTableEntry*>(hdr); entry->~RuleHashTableEntry(); } static void RuleHash_MoveEntry(PLDHashTable *table, const PLDHashEntryHdr *from, PLDHashEntryHdr *to) { NS_PRECONDITION(from != to, "This is not going to work!"); RuleHashTableEntry *oldEntry = const_cast<RuleHashTableEntry*>( static_cast<const RuleHashTableEntry*>(from)); auto* newEntry = new (KnownNotNull, to) RuleHashTableEntry(); newEntry->mRules.SwapElements(oldEntry->mRules); oldEntry->~RuleHashTableEntry(); } static bool RuleHash_TagTable_MatchEntry(const PLDHashEntryHdr *hdr, const void *key) { nsIAtom *match_atom = const_cast<nsIAtom*>(static_cast<const nsIAtom*>(key)); nsIAtom *entry_atom = static_cast<const RuleHashTagTableEntry*>(hdr)->mTag; return match_atom == entry_atom; } static void RuleHash_TagTable_InitEntry(PLDHashEntryHdr *hdr, const void *key) { RuleHashTagTableEntry* entry = static_cast<RuleHashTagTableEntry*>(hdr); new (KnownNotNull, entry) RuleHashTagTableEntry(); entry->mTag = const_cast<nsIAtom*>(static_cast<const nsIAtom*>(key)); } static void RuleHash_TagTable_ClearEntry(PLDHashTable *table, PLDHashEntryHdr *hdr) { RuleHashTagTableEntry* entry = static_cast<RuleHashTagTableEntry*>(hdr); entry->~RuleHashTagTableEntry(); } static void RuleHash_TagTable_MoveEntry(PLDHashTable *table, const PLDHashEntryHdr *from, PLDHashEntryHdr *to) { NS_PRECONDITION(from != to, "This is not going to work!"); RuleHashTagTableEntry *oldEntry = const_cast<RuleHashTagTableEntry*>( static_cast<const RuleHashTagTableEntry*>(from)); auto* newEntry = new (KnownNotNull, to) RuleHashTagTableEntry(); newEntry->mTag.swap(oldEntry->mTag); newEntry->mRules.SwapElements(oldEntry->mRules); oldEntry->~RuleHashTagTableEntry(); } static PLDHashNumber RuleHash_NameSpaceTable_HashKey(const void *key) { return NS_PTR_TO_INT32(key); } static bool RuleHash_NameSpaceTable_MatchEntry(const PLDHashEntryHdr *hdr, const void *key) { const RuleHashTableEntry *entry = static_cast<const RuleHashTableEntry*>(hdr); nsCSSSelector* selector = entry->mRules[0].mSelector; if (selector->IsPseudoElement()) { selector = selector->mNext; } return NS_PTR_TO_INT32(key) == selector->mNameSpace; } static const PLDHashTableOps RuleHash_TagTable_Ops = { PLDHashTable::HashVoidPtrKeyStub, RuleHash_TagTable_MatchEntry, RuleHash_TagTable_MoveEntry, RuleHash_TagTable_ClearEntry, RuleHash_TagTable_InitEntry }; // Case-sensitive ops. static const PLDHashTableOps RuleHash_ClassTable_CSOps = { PLDHashTable::HashVoidPtrKeyStub, RuleHash_ClassCSMatchEntry, RuleHash_MoveEntry, RuleHash_ClearEntry, RuleHash_InitEntry }; // Case-insensitive ops. static const PLDHashTableOps RuleHash_ClassTable_CIOps = { RuleHash_CIHashKey, RuleHash_ClassCIMatchEntry, RuleHash_MoveEntry, RuleHash_ClearEntry, RuleHash_InitEntry }; // Case-sensitive ops. static const PLDHashTableOps RuleHash_IdTable_CSOps = { PLDHashTable::HashVoidPtrKeyStub, RuleHash_IdCSMatchEntry, RuleHash_MoveEntry, RuleHash_ClearEntry, RuleHash_InitEntry }; // Case-insensitive ops. static const PLDHashTableOps RuleHash_IdTable_CIOps = { RuleHash_CIHashKey, RuleHash_IdCIMatchEntry, RuleHash_MoveEntry, RuleHash_ClearEntry, RuleHash_InitEntry }; static const PLDHashTableOps RuleHash_NameSpaceTable_Ops = { RuleHash_NameSpaceTable_HashKey, RuleHash_NameSpaceTable_MatchEntry, RuleHash_MoveEntry, RuleHash_ClearEntry, RuleHash_InitEntry }; #undef RULE_HASH_STATS #undef PRINT_UNIVERSAL_RULES #ifdef RULE_HASH_STATS #define RULE_HASH_STAT_INCREMENT(var_) PR_BEGIN_MACRO ++(var_); PR_END_MACRO #else #define RULE_HASH_STAT_INCREMENT(var_) PR_BEGIN_MACRO PR_END_MACRO #endif struct NodeMatchContext; class RuleHash { public: explicit RuleHash(bool aQuirksMode); ~RuleHash(); void AppendRule(const RuleSelectorPair &aRuleInfo); void EnumerateAllRules(Element* aElement, ElementDependentRuleProcessorData* aData, NodeMatchContext& aNodeMatchContext); size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const; size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const; protected: typedef nsTArray<RuleValue> RuleValueList; void AppendRuleToTable(PLDHashTable* aTable, const void* aKey, const RuleSelectorPair& aRuleInfo); void AppendUniversalRule(const RuleSelectorPair& aRuleInfo); int32_t mRuleCount; PLDHashTable mIdTable; PLDHashTable mClassTable; PLDHashTable mTagTable; PLDHashTable mNameSpaceTable; RuleValueList mUniversalRules; struct EnumData { const RuleValue* mCurValue; const RuleValue* mEnd; }; EnumData* mEnumList; int32_t mEnumListSize; bool mQuirksMode; inline EnumData ToEnumData(const RuleValueList& arr) { EnumData data = { arr.Elements(), arr.Elements() + arr.Length() }; return data; } #ifdef RULE_HASH_STATS uint32_t mUniversalSelectors; uint32_t mNameSpaceSelectors; uint32_t mTagSelectors; uint32_t mClassSelectors; uint32_t mIdSelectors; uint32_t mElementsMatched; uint32_t mElementUniversalCalls; uint32_t mElementNameSpaceCalls; uint32_t mElementTagCalls; uint32_t mElementClassCalls; uint32_t mElementIdCalls; #endif // RULE_HASH_STATS }; RuleHash::RuleHash(bool aQuirksMode) : mRuleCount(0), mIdTable(aQuirksMode ? &RuleHash_IdTable_CIOps : &RuleHash_IdTable_CSOps, sizeof(RuleHashTableEntry)), mClassTable(aQuirksMode ? &RuleHash_ClassTable_CIOps : &RuleHash_ClassTable_CSOps, sizeof(RuleHashTableEntry)), mTagTable(&RuleHash_TagTable_Ops, sizeof(RuleHashTagTableEntry)), mNameSpaceTable(&RuleHash_NameSpaceTable_Ops, sizeof(RuleHashTableEntry)), mUniversalRules(0), mEnumList(nullptr), mEnumListSize(0), mQuirksMode(aQuirksMode) #ifdef RULE_HASH_STATS , mUniversalSelectors(0), mNameSpaceSelectors(0), mTagSelectors(0), mClassSelectors(0), mIdSelectors(0), mElementsMatched(0), mElementUniversalCalls(0), mElementNameSpaceCalls(0), mElementTagCalls(0), mElementClassCalls(0), mElementIdCalls(0) #endif { MOZ_COUNT_CTOR(RuleHash); } RuleHash::~RuleHash() { MOZ_COUNT_DTOR(RuleHash); #ifdef RULE_HASH_STATS printf( "RuleHash(%p):\n" " Selectors: Universal (%u) NameSpace(%u) Tag(%u) Class(%u) Id(%u)\n" " Content Nodes: Elements(%u)\n" " Element Calls: Universal(%u) NameSpace(%u) Tag(%u) Class(%u) Id(%u)\n" static_cast<void*>(this), mUniversalSelectors, mNameSpaceSelectors, mTagSelectors, mClassSelectors, mIdSelectors, mElementsMatched, mElementUniversalCalls, mElementNameSpaceCalls, mElementTagCalls, mElementClassCalls, mElementIdCalls); #ifdef PRINT_UNIVERSAL_RULES { if (mUniversalRules.Length() > 0) { printf(" Universal rules:\n"); for (uint32_t i = 0; i < mUniversalRules.Length(); ++i) { RuleValue* value = &(mUniversalRules[i]); nsAutoString selectorText; uint32_t lineNumber = value->mRule->GetLineNumber(); RefPtr<CSSStyleSheet> cssSheet = value->mRule->GetStyleSheet(); value->mSelector->ToString(selectorText, cssSheet); printf(" line %d, %s\n", lineNumber, NS_ConvertUTF16toUTF8(selectorText).get()); } } } #endif // PRINT_UNIVERSAL_RULES #endif // RULE_HASH_STATS // Rule Values are arena allocated no need to delete them. Their destructor // isn't doing any cleanup. So we dont even bother to enumerate through // the hash tables and call their destructors. if (nullptr != mEnumList) { delete [] mEnumList; } } void RuleHash::AppendRuleToTable(PLDHashTable* aTable, const void* aKey, const RuleSelectorPair& aRuleInfo) { // Get a new or existing entry. auto entry = static_cast<RuleHashTableEntry*>(aTable->Add(aKey, fallible)); if (!entry) return; entry->mRules.AppendElement(RuleValue(aRuleInfo, mRuleCount++, mQuirksMode)); } static void AppendRuleToTagTable(PLDHashTable* aTable, nsIAtom* aKey, const RuleValue& aRuleInfo) { // Get a new or exisiting entry auto entry = static_cast<RuleHashTagTableEntry*>(aTable->Add(aKey, fallible)); if (!entry) return; entry->mRules.AppendElement(aRuleInfo); } void RuleHash::AppendUniversalRule(const RuleSelectorPair& aRuleInfo) { mUniversalRules.AppendElement(RuleValue(aRuleInfo, mRuleCount++, mQuirksMode)); } void RuleHash::AppendRule(const RuleSelectorPair& aRuleInfo) { nsCSSSelector *selector = aRuleInfo.mSelector; if (selector->IsPseudoElement()) { selector = selector->mNext; } if (nullptr != selector->mIDList) { AppendRuleToTable(&mIdTable, selector->mIDList->mAtom, aRuleInfo); RULE_HASH_STAT_INCREMENT(mIdSelectors); } else if (nullptr != selector->mClassList) { AppendRuleToTable(&mClassTable, selector->mClassList->mAtom, aRuleInfo); RULE_HASH_STAT_INCREMENT(mClassSelectors); } else if (selector->mLowercaseTag) { RuleValue ruleValue(aRuleInfo, mRuleCount++, mQuirksMode); AppendRuleToTagTable(&mTagTable, selector->mLowercaseTag, ruleValue); RULE_HASH_STAT_INCREMENT(mTagSelectors); if (selector->mCasedTag && selector->mCasedTag != selector->mLowercaseTag) { AppendRuleToTagTable(&mTagTable, selector->mCasedTag, ruleValue); RULE_HASH_STAT_INCREMENT(mTagSelectors); } } else if (kNameSpaceID_Unknown != selector->mNameSpace) { AppendRuleToTable(&mNameSpaceTable, NS_INT32_TO_PTR(selector->mNameSpace), aRuleInfo); RULE_HASH_STAT_INCREMENT(mNameSpaceSelectors); } else { // universal tag selector AppendUniversalRule(aRuleInfo); RULE_HASH_STAT_INCREMENT(mUniversalSelectors); } } // this should cover practically all cases so we don't need to reallocate #define MIN_ENUM_LIST_SIZE 8 #ifdef RULE_HASH_STATS #define RULE_HASH_STAT_INCREMENT_LIST_COUNT(list_, var_) \ (var_) += (list_).Length() #else #define RULE_HASH_STAT_INCREMENT_LIST_COUNT(list_, var_) \ PR_BEGIN_MACRO PR_END_MACRO #endif static inline void ContentEnumFunc(const RuleValue &value, nsCSSSelector* selector, ElementDependentRuleProcessorData* data, NodeMatchContext& nodeContext, AncestorFilter *ancestorFilter); void RuleHash::EnumerateAllRules(Element* aElement, ElementDependentRuleProcessorData* aData, NodeMatchContext& aNodeContext) { int32_t nameSpace = aElement->GetNameSpaceID(); nsIAtom* tag = aElement->NodeInfo()->NameAtom(); nsIAtom* id = aElement->GetID(); const nsAttrValue* classList = aElement->GetClasses(); MOZ_ASSERT(tag, "How could we not have a tag?"); int32_t classCount = classList ? classList->GetAtomCount() : 0; // assume 1 universal, tag, id, and namespace, rather than wasting // time counting int32_t testCount = classCount + 4; if (mEnumListSize < testCount) { delete [] mEnumList; mEnumListSize = std::max(testCount, MIN_ENUM_LIST_SIZE); mEnumList = new EnumData[mEnumListSize]; } int32_t valueCount = 0; RULE_HASH_STAT_INCREMENT(mElementsMatched); if (mUniversalRules.Length() != 0) { // universal rules mEnumList[valueCount++] = ToEnumData(mUniversalRules); RULE_HASH_STAT_INCREMENT_LIST_COUNT(mUniversalRules, mElementUniversalCalls); } // universal rules within the namespace if (kNameSpaceID_Unknown != nameSpace && mNameSpaceTable.EntryCount() > 0) { auto entry = static_cast<RuleHashTableEntry*> (mNameSpaceTable.Search(NS_INT32_TO_PTR(nameSpace))); if (entry) { mEnumList[valueCount++] = ToEnumData(entry->mRules); RULE_HASH_STAT_INCREMENT_LIST_COUNT(entry->mRules, mElementNameSpaceCalls); } } if (mTagTable.EntryCount() > 0) { auto entry = static_cast<RuleHashTableEntry*>(mTagTable.Search(tag)); if (entry) { mEnumList[valueCount++] = ToEnumData(entry->mRules); RULE_HASH_STAT_INCREMENT_LIST_COUNT(entry->mRules, mElementTagCalls); } } if (id && mIdTable.EntryCount() > 0) { auto entry = static_cast<RuleHashTableEntry*>(mIdTable.Search(id)); if (entry) { mEnumList[valueCount++] = ToEnumData(entry->mRules); RULE_HASH_STAT_INCREMENT_LIST_COUNT(entry->mRules, mElementIdCalls); } } if (mClassTable.EntryCount() > 0) { for (int32_t index = 0; index < classCount; ++index) { auto entry = static_cast<RuleHashTableEntry*> (mClassTable.Search(classList->AtomAt(index))); if (entry) { mEnumList[valueCount++] = ToEnumData(entry->mRules); RULE_HASH_STAT_INCREMENT_LIST_COUNT(entry->mRules, mElementClassCalls); } } } NS_ASSERTION(valueCount <= testCount, "values exceeded list size"); if (valueCount > 0) { AncestorFilter *filter = aData->mTreeMatchContext.mAncestorFilter.HasFilter() ? &aData->mTreeMatchContext.mAncestorFilter : nullptr; #ifdef DEBUG if (filter) { filter->AssertHasAllAncestors(aElement); } #endif // Merge the lists while there are still multiple lists to merge. while (valueCount > 1) { int32_t valueIndex = 0; int32_t lowestRuleIndex = mEnumList[valueIndex].mCurValue->mIndex; for (int32_t index = 1; index < valueCount; ++index) { int32_t ruleIndex = mEnumList[index].mCurValue->mIndex; if (ruleIndex < lowestRuleIndex) { valueIndex = index; lowestRuleIndex = ruleIndex; } } const RuleValue *cur = mEnumList[valueIndex].mCurValue; ContentEnumFunc(*cur, cur->mSelector, aData, aNodeContext, filter); cur++; if (cur == mEnumList[valueIndex].mEnd) { mEnumList[valueIndex] = mEnumList[--valueCount]; } else { mEnumList[valueIndex].mCurValue = cur; } } // Fast loop over single value. for (const RuleValue *value = mEnumList[0].mCurValue, *end = mEnumList[0].mEnd; value != end; ++value) { ContentEnumFunc(*value, value->mSelector, aData, aNodeContext, filter); } } } static size_t SizeOfRuleHashTable(const PLDHashTable& aTable, MallocSizeOf aMallocSizeOf) { size_t n = aTable.ShallowSizeOfExcludingThis(aMallocSizeOf); for (auto iter = aTable.ConstIter(); !iter.Done(); iter.Next()) { auto entry = static_cast<RuleHashTableEntry*>(iter.Get()); n += entry->mRules.ShallowSizeOfExcludingThis(aMallocSizeOf); } return n; } size_t RuleHash::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const { size_t n = 0; n += SizeOfRuleHashTable(mIdTable, aMallocSizeOf); n += SizeOfRuleHashTable(mClassTable, aMallocSizeOf); n += SizeOfRuleHashTable(mTagTable, aMallocSizeOf); n += SizeOfRuleHashTable(mNameSpaceTable, aMallocSizeOf); n += mUniversalRules.ShallowSizeOfExcludingThis(aMallocSizeOf); return n; } size_t RuleHash::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const { return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf); } //-------------------------------- /** * A struct that stores an nsCSSSelector pointer along side a pointer to * the rightmost nsCSSSelector in the selector. For example, for * * .main p > span * * if mSelector points to the |p| nsCSSSelector, mRightmostSelector would * point to the |span| nsCSSSelector. * * Both mSelector and mRightmostSelector are always top-level selectors, * i.e. they aren't selectors within a :not() or :-moz-any(). */ struct SelectorPair { SelectorPair(nsCSSSelector* aSelector, nsCSSSelector* aRightmostSelector) : mSelector(aSelector), mRightmostSelector(aRightmostSelector) { MOZ_ASSERT(aSelector); MOZ_ASSERT(mRightmostSelector); } SelectorPair(const SelectorPair& aOther) = default; nsCSSSelector* const mSelector; nsCSSSelector* const mRightmostSelector; }; // A hash table mapping atoms to lists of selectors struct AtomSelectorEntry : public PLDHashEntryHdr { nsIAtom *mAtom; // Auto length 2, because a decent fraction of these arrays ends up // with 2 elements, and each entry is cheap. AutoTArray<SelectorPair, 2> mSelectors; }; static void AtomSelector_ClearEntry(PLDHashTable *table, PLDHashEntryHdr *hdr) { (static_cast<AtomSelectorEntry*>(hdr))->~AtomSelectorEntry(); } static void AtomSelector_InitEntry(PLDHashEntryHdr *hdr, const void *key) { AtomSelectorEntry *entry = static_cast<AtomSelectorEntry*>(hdr); new (KnownNotNull, entry) AtomSelectorEntry(); entry->mAtom = const_cast<nsIAtom*>(static_cast<const nsIAtom*>(key)); } static void AtomSelector_MoveEntry(PLDHashTable *table, const PLDHashEntryHdr *from, PLDHashEntryHdr *to) { NS_PRECONDITION(from != to, "This is not going to work!"); AtomSelectorEntry *oldEntry = const_cast<AtomSelectorEntry*>(static_cast<const AtomSelectorEntry*>(from)); auto* newEntry = new (KnownNotNull, to) AtomSelectorEntry(); newEntry->mAtom = oldEntry->mAtom; newEntry->mSelectors.SwapElements(oldEntry->mSelectors); oldEntry->~AtomSelectorEntry(); } static bool AtomSelector_CIMatchEntry(const PLDHashEntryHdr *hdr, const void *key) { const AtomSelectorEntry *entry = static_cast<const AtomSelectorEntry*>(hdr); return CIMatchAtoms(key, entry->mAtom); } // Case-sensitive ops. static const PLDHashTableOps AtomSelector_CSOps = { PLDHashTable::HashVoidPtrKeyStub, PLDHashTable::MatchEntryStub, AtomSelector_MoveEntry, AtomSelector_ClearEntry, AtomSelector_InitEntry }; // Case-insensitive ops. static const PLDHashTableOps AtomSelector_CIOps = { RuleHash_CIHashKey, AtomSelector_CIMatchEntry, AtomSelector_MoveEntry, AtomSelector_ClearEntry, AtomSelector_InitEntry }; //-------------------------------- struct RuleCascadeData { RuleCascadeData(nsIAtom *aMedium, bool aQuirksMode) : mRuleHash(aQuirksMode), mStateSelectors(), mSelectorDocumentStates(0), mClassSelectors(aQuirksMode ? &AtomSelector_CIOps : &AtomSelector_CSOps, sizeof(AtomSelectorEntry)), mIdSelectors(aQuirksMode ? &AtomSelector_CIOps : &AtomSelector_CSOps, sizeof(AtomSelectorEntry)), // mAttributeSelectors is matching on the attribute _name_, not the // value, and we case-fold names at parse-time, so this is a // case-sensitive match. mAttributeSelectors(&AtomSelector_CSOps, sizeof(AtomSelectorEntry)), mAnonBoxRules(&RuleHash_TagTable_Ops, sizeof(RuleHashTagTableEntry)), #ifdef MOZ_XUL mXULTreeRules(&RuleHash_TagTable_Ops, sizeof(RuleHashTagTableEntry)), #endif mKeyframesRuleTable(), mCounterStyleRuleTable(), mCacheKey(aMedium), mNext(nullptr), mQuirksMode(aQuirksMode) { memset(mPseudoElementRuleHashes, 0, sizeof(mPseudoElementRuleHashes)); } ~RuleCascadeData() { for (uint32_t i = 0; i < ArrayLength(mPseudoElementRuleHashes); ++i) { delete mPseudoElementRuleHashes[i]; } } size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const; RuleHash mRuleHash; RuleHash* mPseudoElementRuleHashes[ static_cast<CSSPseudoElementTypeBase>(CSSPseudoElementType::Count)]; nsTArray<nsCSSRuleProcessor::StateSelector> mStateSelectors; EventStates mSelectorDocumentStates; PLDHashTable mClassSelectors; PLDHashTable mIdSelectors; nsTArray<nsCSSSelector*> mPossiblyNegatedClassSelectors; nsTArray<nsCSSSelector*> mPossiblyNegatedIDSelectors; PLDHashTable mAttributeSelectors; PLDHashTable mAnonBoxRules; #ifdef MOZ_XUL PLDHashTable mXULTreeRules; #endif nsTArray<nsFontFaceRuleContainer> mFontFaceRules; nsTArray<nsCSSKeyframesRule*> mKeyframesRules; nsTArray<nsCSSFontFeatureValuesRule*> mFontFeatureValuesRules; nsTArray<nsCSSPageRule*> mPageRules; nsTArray<nsCSSCounterStyleRule*> mCounterStyleRules; nsDataHashtable<nsStringHashKey, nsCSSKeyframesRule*> mKeyframesRuleTable; nsDataHashtable<nsStringHashKey, nsCSSCounterStyleRule*> mCounterStyleRuleTable; // Looks up or creates the appropriate list in |mAttributeSelectors|. // Returns null only on allocation failure. nsTArray<SelectorPair>* AttributeListFor(nsIAtom* aAttribute); nsMediaQueryResultCacheKey mCacheKey; RuleCascadeData* mNext; // for a different medium const bool mQuirksMode; }; static size_t SizeOfSelectorsHashTable(const PLDHashTable& aTable, MallocSizeOf aMallocSizeOf) { size_t n = aTable.ShallowSizeOfExcludingThis(aMallocSizeOf); for (auto iter = aTable.ConstIter(); !iter.Done(); iter.Next()) { auto entry = static_cast<AtomSelectorEntry*>(iter.Get()); n += entry->mSelectors.ShallowSizeOfExcludingThis(aMallocSizeOf); } return n; } size_t RuleCascadeData::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const { size_t n = aMallocSizeOf(this); n += mRuleHash.SizeOfExcludingThis(aMallocSizeOf); for (uint32_t i = 0; i < ArrayLength(mPseudoElementRuleHashes); ++i) { if (mPseudoElementRuleHashes[i]) n += mPseudoElementRuleHashes[i]->SizeOfIncludingThis(aMallocSizeOf); } n += mStateSelectors.ShallowSizeOfExcludingThis(aMallocSizeOf); n += SizeOfSelectorsHashTable(mIdSelectors, aMallocSizeOf); n += SizeOfSelectorsHashTable(mClassSelectors, aMallocSizeOf); n += mPossiblyNegatedClassSelectors.ShallowSizeOfExcludingThis(aMallocSizeOf); n += mPossiblyNegatedIDSelectors.ShallowSizeOfExcludingThis(aMallocSizeOf); n += SizeOfSelectorsHashTable(mAttributeSelectors, aMallocSizeOf); n += SizeOfRuleHashTable(mAnonBoxRules, aMallocSizeOf); #ifdef MOZ_XUL n += SizeOfRuleHashTable(mXULTreeRules, aMallocSizeOf); #endif n += mFontFaceRules.ShallowSizeOfExcludingThis(aMallocSizeOf); n += mKeyframesRules.ShallowSizeOfExcludingThis(aMallocSizeOf); n += mFontFeatureValuesRules.ShallowSizeOfExcludingThis(aMallocSizeOf); n += mPageRules.ShallowSizeOfExcludingThis(aMallocSizeOf); n += mCounterStyleRules.ShallowSizeOfExcludingThis(aMallocSizeOf); n += mKeyframesRuleTable.ShallowSizeOfExcludingThis(aMallocSizeOf); for (auto iter = mKeyframesRuleTable.ConstIter(); !iter.Done(); iter.Next()) { // We don't own the nsCSSKeyframesRule objects so we don't count them. We // do care about the size of the keys' nsAString members' buffers though. // // Note that we depend on nsStringHashKey::GetKey() returning a reference, // since otherwise aKey would be a copy of the string key and we would not // be measuring the right object here. n += iter.Key().SizeOfExcludingThisIfUnshared(aMallocSizeOf); } return n; } nsTArray<SelectorPair>* RuleCascadeData::AttributeListFor(nsIAtom* aAttribute) { auto entry = static_cast<AtomSelectorEntry*> (mAttributeSelectors.Add(aAttribute, fallible)); if (!entry) return nullptr; return &entry->mSelectors; } // ------------------------------- // CSS Style rule processor implementation // nsCSSRuleProcessor::nsCSSRuleProcessor(const sheet_array_type& aSheets, SheetType aSheetType, Element* aScopeElement, nsCSSRuleProcessor* aPreviousCSSRuleProcessor, bool aIsShared) : nsCSSRuleProcessor(sheet_array_type(aSheets), aSheetType, aScopeElement, aPreviousCSSRuleProcessor, aIsShared) { } nsCSSRuleProcessor::nsCSSRuleProcessor(sheet_array_type&& aSheets, SheetType aSheetType, Element* aScopeElement, nsCSSRuleProcessor* aPreviousCSSRuleProcessor, bool aIsShared) : mSheets(aSheets) , mRuleCascades(nullptr) , mPreviousCacheKey(aPreviousCSSRuleProcessor ? aPreviousCSSRuleProcessor->CloneMQCacheKey() : UniquePtr<nsMediaQueryResultCacheKey>()) , mLastPresContext(nullptr) , mScopeElement(aScopeElement) , mStyleSetRefCnt(0) , mSheetType(aSheetType) , mIsShared(aIsShared) , mMustGatherDocumentRules(aIsShared) , mInRuleProcessorCache(false) #ifdef DEBUG , mDocumentRulesAndCacheKeyValid(false) #endif { NS_ASSERTION(!!mScopeElement == (aSheetType == SheetType::ScopedDoc), "aScopeElement must be specified iff aSheetType is " "eScopedDocSheet"); for (sheet_array_type::size_type i = mSheets.Length(); i-- != 0; ) { mSheets[i]->AddRuleProcessor(this); } } nsCSSRuleProcessor::~nsCSSRuleProcessor() { if (mInRuleProcessorCache) { RuleProcessorCache::RemoveRuleProcessor(this); } MOZ_ASSERT(!mExpirationState.IsTracked()); MOZ_ASSERT(mStyleSetRefCnt == 0); ClearSheets(); ClearRuleCascades(); } NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsCSSRuleProcessor) NS_INTERFACE_MAP_ENTRY(nsIStyleRuleProcessor) NS_INTERFACE_MAP_END NS_IMPL_CYCLE_COLLECTING_ADDREF(nsCSSRuleProcessor) NS_IMPL_CYCLE_COLLECTING_RELEASE(nsCSSRuleProcessor) NS_IMPL_CYCLE_COLLECTION_CLASS(nsCSSRuleProcessor) NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsCSSRuleProcessor) tmp->ClearSheets(); NS_IMPL_CYCLE_COLLECTION_UNLINK(mScopeElement) NS_IMPL_CYCLE_COLLECTION_UNLINK_END NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsCSSRuleProcessor) NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSheets) NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mScopeElement) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END void nsCSSRuleProcessor::ClearSheets() { for (sheet_array_type::size_type i = mSheets.Length(); i-- != 0; ) { mSheets[i]->DropRuleProcessor(this); } mSheets.Clear(); } /* static */ void nsCSSRuleProcessor::Startup() { Preferences::AddBoolVarCache(&gSupportVisitedPseudo, VISITED_PSEUDO_PREF, true); } static bool InitSystemMetrics() { NS_ASSERTION(!sSystemMetrics, "already initialized"); sSystemMetrics = new nsTArray< nsCOMPtr<nsIAtom> >; NS_ENSURE_TRUE(sSystemMetrics, false); /*************************************************************************** * ANY METRICS ADDED HERE SHOULD ALSO BE ADDED AS MEDIA QUERIES IN * * nsMediaFeatures.cpp * ***************************************************************************/ int32_t metricResult = LookAndFeel::GetInt(LookAndFeel::eIntID_ScrollArrowStyle); if (metricResult & LookAndFeel::eScrollArrow_StartBackward) { sSystemMetrics->AppendElement(nsGkAtoms::scrollbar_start_backward); } if (metricResult & LookAndFeel::eScrollArrow_StartForward) { sSystemMetrics->AppendElement(nsGkAtoms::scrollbar_start_forward); } if (metricResult & LookAndFeel::eScrollArrow_EndBackward) { sSystemMetrics->AppendElement(nsGkAtoms::scrollbar_end_backward); } if (metricResult & LookAndFeel::eScrollArrow_EndForward) { sSystemMetrics->AppendElement(nsGkAtoms::scrollbar_end_forward); } metricResult = LookAndFeel::GetInt(LookAndFeel::eIntID_ScrollSliderStyle); if (metricResult != LookAndFeel::eScrollThumbStyle_Normal) { sSystemMetrics->AppendElement(nsGkAtoms::scrollbar_thumb_proportional); } metricResult = LookAndFeel::GetInt(LookAndFeel::eIntID_UseOverlayScrollbars); if (metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::overlay_scrollbars); } metricResult = LookAndFeel::GetInt(LookAndFeel::eIntID_MenuBarDrag); if (metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::menubar_drag); } nsresult rv = LookAndFeel::GetInt(LookAndFeel::eIntID_WindowsDefaultTheme, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::windows_default_theme); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_MacGraphiteTheme, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::mac_graphite_theme); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_MacYosemiteTheme, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::mac_yosemite_theme); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_DWMCompositor, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::windows_compositor); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_WindowsGlass, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::windows_glass); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_ColorPickerAvailable, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::color_picker_available); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_WindowsClassic, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::windows_classic); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_TouchEnabled, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::touch_enabled); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_SwipeAnimationEnabled, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::swipe_animation_enabled); } rv = LookAndFeel::GetInt(LookAndFeel::eIntID_PhysicalHomeButton, &metricResult); if (NS_SUCCEEDED(rv) && metricResult) { sSystemMetrics->AppendElement(nsGkAtoms::physical_home_button); } #ifdef XP_WIN if (NS_SUCCEEDED( LookAndFeel::GetInt(LookAndFeel::eIntID_WindowsThemeIdentifier, &metricResult))) { nsCSSRuleProcessor::SetWindowsThemeIdentifier(static_cast<uint8_t>(metricResult)); switch(metricResult) { case LookAndFeel::eWindowsTheme_Aero: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_aero); break; case LookAndFeel::eWindowsTheme_AeroLite: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_aero_lite); break; case LookAndFeel::eWindowsTheme_LunaBlue: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_luna_blue); break; case LookAndFeel::eWindowsTheme_LunaOlive: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_luna_olive); break; case LookAndFeel::eWindowsTheme_LunaSilver: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_luna_silver); break; case LookAndFeel::eWindowsTheme_Royale: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_royale); break; case LookAndFeel::eWindowsTheme_Zune: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_zune); break; case LookAndFeel::eWindowsTheme_Generic: sSystemMetrics->AppendElement(nsGkAtoms::windows_theme_generic); break; } } #endif return true; } /* static */ void nsCSSRuleProcessor::FreeSystemMetrics() { delete sSystemMetrics; sSystemMetrics = nullptr; } /* static */ void nsCSSRuleProcessor::Shutdown() { FreeSystemMetrics(); } /* static */ bool nsCSSRuleProcessor::HasSystemMetric(nsIAtom* aMetric) { if (!sSystemMetrics && !InitSystemMetrics()) { return false; } return sSystemMetrics->IndexOf(aMetric) != sSystemMetrics->NoIndex; } #ifdef XP_WIN /* static */ uint8_t nsCSSRuleProcessor::GetWindowsThemeIdentifier() { if (!sSystemMetrics) InitSystemMetrics(); return sWinThemeId; } #endif /* static */ EventStates nsCSSRuleProcessor::GetContentState(Element* aElement, const TreeMatchContext& aTreeMatchContext) { EventStates state = aElement->StyleState(); // If we are not supposed to mark visited links as such, be sure to // flip the bits appropriately. We want to do this here, rather // than in GetContentStateForVisitedHandling, so that we don't // expose that :visited support is disabled to the Web page. if (state.HasState(NS_EVENT_STATE_VISITED) && (!gSupportVisitedPseudo || aElement->OwnerDoc()->IsBeingUsedAsImage() || aTreeMatchContext.mUsingPrivateBrowsing)) { state &= ~NS_EVENT_STATE_VISITED; state |= NS_EVENT_STATE_UNVISITED; } return state; } /* static */ bool nsCSSRuleProcessor::IsLink(const Element* aElement) { EventStates state = aElement->StyleState(); return state.HasAtLeastOneOfStates(NS_EVENT_STATE_VISITED | NS_EVENT_STATE_UNVISITED); } /* static */ EventStates nsCSSRuleProcessor::GetContentStateForVisitedHandling( Element* aElement, const TreeMatchContext& aTreeMatchContext, nsRuleWalker::VisitedHandlingType aVisitedHandling, bool aIsRelevantLink) { EventStates contentState = GetContentState(aElement, aTreeMatchContext); if (contentState.HasAtLeastOneOfStates(NS_EVENT_STATE_VISITED | NS_EVENT_STATE_UNVISITED)) { MOZ_ASSERT(IsLink(aElement), "IsLink() should match state"); contentState &= ~(NS_EVENT_STATE_VISITED | NS_EVENT_STATE_UNVISITED); if (aIsRelevantLink) { switch (aVisitedHandling) { case nsRuleWalker::eRelevantLinkUnvisited: contentState |= NS_EVENT_STATE_UNVISITED; break; case nsRuleWalker::eRelevantLinkVisited: contentState |= NS_EVENT_STATE_VISITED; break; case nsRuleWalker::eLinksVisitedOrUnvisited: contentState |= NS_EVENT_STATE_UNVISITED | NS_EVENT_STATE_VISITED; break; } } else { contentState |= NS_EVENT_STATE_UNVISITED; } } return contentState; } /** * A |NodeMatchContext| has data about matching a selector (without * combinators) against a single node. It contains only input to the * matching. * * Unlike |RuleProcessorData|, which is similar, a |NodeMatchContext| * can vary depending on the selector matching process. In other words, * there might be multiple NodeMatchContexts corresponding to a single * node, but only one possible RuleProcessorData. */ struct NodeMatchContext { // In order to implement nsCSSRuleProcessor::HasStateDependentStyle, // we need to be able to see if a node might match an // event-state-dependent selector for any value of that event state. // So mStateMask contains the states that should NOT be tested. // // NOTE: For |mStateMask| to work correctly, it's important that any // change that changes multiple state bits include all those state // bits in the notification. Otherwise, if multiple states change but // we do separate notifications then we might determine the style is // not state-dependent when it really is (e.g., determining that a // :hover:active rule no longer matches when both states are unset). const EventStates mStateMask; // Is this link the unique link whose visitedness can affect the style // of the node being matched? (That link is the nearest link to the // node being matched that is itself or an ancestor.) // // Always false when TreeMatchContext::mForStyling is false. (We // could figure it out for SelectorListMatches, but we're starting // from the middle of the selector list when doing // Has{Attribute,State}DependentStyle, so we can't tell. So when // mForStyling is false, we have to assume we don't know.) const bool mIsRelevantLink; NodeMatchContext(EventStates aStateMask, bool aIsRelevantLink) : mStateMask(aStateMask) , mIsRelevantLink(aIsRelevantLink) { } }; /** * Additional information about a selector (without combinators) that is * being matched. */ enum class SelectorMatchesFlags : uint8_t { NONE = 0, // The selector's flags are unknown. This happens when you don't know // if you're starting from the top of a selector. Only used in cases // where it's acceptable for matching to return a false positive. // (It's not OK to return a false negative.) UNKNOWN = 1 << 0, // The selector is part of a compound selector which has been split in // half, where the other half is a pseudo-element. The current // selector is not a pseudo-element itself. HAS_PSEUDO_ELEMENT = 1 << 1, // The selector is part of an argument to a functional pseudo-class or // pseudo-element. IS_PSEUDO_CLASS_ARGUMENT = 1 << 2 }; MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(SelectorMatchesFlags) // Return whether the selector matches conditions for the :active and // :hover quirk. static inline bool ActiveHoverQuirkMatches(nsCSSSelector* aSelector, SelectorMatchesFlags aSelectorFlags) { if (aSelector->HasTagSelector() || aSelector->mAttrList || aSelector->mIDList || aSelector->mClassList || aSelector->IsPseudoElement() || // Having this quirk means that some selectors will no longer match, // so it's better to return false when we aren't sure (i.e., the // flags are unknown). aSelectorFlags & (SelectorMatchesFlags::UNKNOWN | SelectorMatchesFlags::HAS_PSEUDO_ELEMENT | SelectorMatchesFlags::IS_PSEUDO_CLASS_ARGUMENT)) { return false; } // No pseudo-class other than :active and :hover. for (nsPseudoClassList* pseudoClass = aSelector->mPseudoClassList; pseudoClass; pseudoClass = pseudoClass->mNext) { if (pseudoClass->mType != CSSPseudoClassType::hover && pseudoClass->mType != CSSPseudoClassType::active) { return false; } } return true; } static inline bool IsSignificantChild(nsIContent* aChild, bool aTextIsSignificant, bool aWhitespaceIsSignificant) { return nsStyleUtil::IsSignificantChild(aChild, aTextIsSignificant, aWhitespaceIsSignificant); } // This function is to be called once we have fetched a value for an attribute // whose namespace and name match those of aAttrSelector. This function // performs comparisons on the value only, based on aAttrSelector->mFunction. static bool AttrMatchesValue(const nsAttrSelector* aAttrSelector, const nsString& aValue, bool isHTML) { NS_PRECONDITION(aAttrSelector, "Must have an attribute selector"); // http://lists.w3.org/Archives/Public/www-style/2008Apr/0038.html // *= (CONTAINSMATCH) ~= (INCLUDES) ^= (BEGINSMATCH) $= (ENDSMATCH) // all accept the empty string, but match nothing. if (aAttrSelector->mValue.IsEmpty() && (aAttrSelector->mFunction == NS_ATTR_FUNC_INCLUDES || aAttrSelector->mFunction == NS_ATTR_FUNC_ENDSMATCH || aAttrSelector->mFunction == NS_ATTR_FUNC_BEGINSMATCH || aAttrSelector->mFunction == NS_ATTR_FUNC_CONTAINSMATCH)) return false; const nsDefaultStringComparator defaultComparator; const nsASCIICaseInsensitiveStringComparator ciComparator; const nsStringComparator& comparator = aAttrSelector->IsValueCaseSensitive(isHTML) ? static_cast<const nsStringComparator&>(defaultComparator) : static_cast<const nsStringComparator&>(ciComparator); switch (aAttrSelector->mFunction) { case NS_ATTR_FUNC_EQUALS: return aValue.Equals(aAttrSelector->mValue, comparator); case NS_ATTR_FUNC_INCLUDES: return nsStyleUtil::ValueIncludes(aValue, aAttrSelector->mValue, comparator); case NS_ATTR_FUNC_DASHMATCH: return nsStyleUtil::DashMatchCompare(aValue, aAttrSelector->mValue, comparator); case NS_ATTR_FUNC_ENDSMATCH: return StringEndsWith(aValue, aAttrSelector->mValue, comparator); case NS_ATTR_FUNC_BEGINSMATCH: return StringBeginsWith(aValue, aAttrSelector->mValue, comparator); case NS_ATTR_FUNC_CONTAINSMATCH: return FindInReadable(aAttrSelector->mValue, aValue, comparator); default: NS_NOTREACHED("Shouldn't be ending up here"); return false; } } static inline bool edgeChildMatches(Element* aElement, TreeMatchContext& aTreeMatchContext, bool checkFirst, bool checkLast) { nsIContent* parent = aElement->GetParent(); if (parent && aTreeMatchContext.mForStyling) parent->SetFlags(NODE_HAS_EDGE_CHILD_SELECTOR); return (!checkFirst || aTreeMatchContext.mNthIndexCache. GetNthIndex(aElement, false, false, true) == 1) && (!checkLast || aTreeMatchContext.mNthIndexCache. GetNthIndex(aElement, false, true, true) == 1); } static inline bool nthChildGenericMatches(Element* aElement, TreeMatchContext& aTreeMatchContext, nsPseudoClassList* pseudoClass, bool isOfType, bool isFromEnd) { nsIContent* parent = aElement->GetParent(); if (parent && aTreeMatchContext.mForStyling) { if (isFromEnd) parent->SetFlags(NODE_HAS_SLOW_SELECTOR); else parent->SetFlags(NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS); } const int32_t index = aTreeMatchContext.mNthIndexCache. GetNthIndex(aElement, isOfType, isFromEnd, false); if (index <= 0) { // Node is anonymous content (not really a child of its parent). return false; } const int32_t a = pseudoClass->u.mNumbers[0]; const int32_t b = pseudoClass->u.mNumbers[1]; // result should be true if there exists n >= 0 such that // a * n + b == index. if (a == 0) { return b == index; } // Integer division in C does truncation (towards 0). So // check that the result is nonnegative, and that there was no // truncation. const CheckedInt<int32_t> indexMinusB = CheckedInt<int32_t>(index) - b; const CheckedInt<int32_t> n = indexMinusB / a; return n.isValid() && n.value() >= 0 && a * n == indexMinusB; } static inline bool edgeOfTypeMatches(Element* aElement, TreeMatchContext& aTreeMatchContext, bool checkFirst, bool checkLast) { nsIContent *parent = aElement->GetParent(); if (parent && aTreeMatchContext.mForStyling) { if (checkLast) parent->SetFlags(NODE_HAS_SLOW_SELECTOR); else parent->SetFlags(NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS); } return (!checkFirst || aTreeMatchContext.mNthIndexCache. GetNthIndex(aElement, true, false, true) == 1) && (!checkLast || aTreeMatchContext.mNthIndexCache. GetNthIndex(aElement, true, true, true) == 1); } static inline bool checkGenericEmptyMatches(Element* aElement, TreeMatchContext& aTreeMatchContext, bool isWhitespaceSignificant) { nsIContent *child = nullptr; int32_t index = -1; if (aTreeMatchContext.mForStyling) aElement->SetFlags(NODE_HAS_EMPTY_SELECTOR); do { child = aElement->GetChildAt(++index); // stop at first non-comment (and non-whitespace for // :-moz-only-whitespace) node } while (child && !IsSignificantChild(child, true, isWhitespaceSignificant)); return (child == nullptr); } // Arrays of the states that are relevant for various pseudoclasses. static const EventStates sPseudoClassStateDependences[] = { #define CSS_PSEUDO_CLASS(_name, _value, _flags, _pref) \ EventStates(), #define CSS_STATE_DEPENDENT_PSEUDO_CLASS(_name, _value, _flags, _pref, _states) \ _states, #include "nsCSSPseudoClassList.h" #undef CSS_STATE_DEPENDENT_PSEUDO_CLASS #undef CSS_PSEUDO_CLASS // Add more entries for our fake values to make sure we can't // index out of bounds into this array no matter what. EventStates(), EventStates() }; static const EventStates sPseudoClassStates[] = { #define CSS_PSEUDO_CLASS(_name, _value, _flags, _pref) \ EventStates(), #define CSS_STATE_PSEUDO_CLASS(_name, _value, _flags, _pref, _states) \ _states, #include "nsCSSPseudoClassList.h" #undef CSS_STATE_PSEUDO_CLASS #undef CSS_PSEUDO_CLASS // Add more entries for our fake values to make sure we can't // index out of bounds into this array no matter what. EventStates(), EventStates() }; static_assert(MOZ_ARRAY_LENGTH(sPseudoClassStates) == static_cast<size_t>(CSSPseudoClassType::MAX), "CSSPseudoClassType::MAX is no longer equal to the length of " "sPseudoClassStates"); static bool StateSelectorMatches(Element* aElement, nsCSSSelector* aSelector, NodeMatchContext& aNodeMatchContext, TreeMatchContext& aTreeMatchContext, SelectorMatchesFlags aSelectorFlags, bool* const aDependence, EventStates aStatesToCheck) { NS_PRECONDITION(!aStatesToCheck.IsEmpty(), "should only need to call StateSelectorMatches if " "aStatesToCheck is not empty"); // Bit-based pseudo-classes if (aStatesToCheck.HasAtLeastOneOfStates(NS_EVENT_STATE_ACTIVE | NS_EVENT_STATE_HOVER) && aTreeMatchContext.mCompatMode == eCompatibility_NavQuirks && ActiveHoverQuirkMatches(aSelector, aSelectorFlags) && aElement->IsHTMLElement() && !nsCSSRuleProcessor::IsLink(aElement)) { // In quirks mode, only make links sensitive to selectors ":active" // and ":hover". return false; } if (aTreeMatchContext.mForStyling && aStatesToCheck.HasAtLeastOneOfStates(NS_EVENT_STATE_HOVER)) { // Mark the element as having :hover-dependent style aElement->SetHasRelevantHoverRules(); } if (aNodeMatchContext.mStateMask.HasAtLeastOneOfStates(aStatesToCheck)) { if (aDependence) { *aDependence = true; } } else { EventStates contentState = nsCSSRuleProcessor::GetContentStateForVisitedHandling( aElement, aTreeMatchContext, aTreeMatchContext.VisitedHandling(), aNodeMatchContext.mIsRelevantLink); if (!contentState.HasAtLeastOneOfStates(aStatesToCheck)) { return false; } } return true; } static bool StateSelectorMatches(Element* aElement, nsCSSSelector* aSelector, NodeMatchContext& aNodeMatchContext, TreeMatchContext& aTreeMatchContext, SelectorMatchesFlags aSelectorFlags) { for (nsPseudoClassList* pseudoClass = aSelector->mPseudoClassList; pseudoClass; pseudoClass = pseudoClass->mNext) { auto idx = static_cast<CSSPseudoClassTypeBase>(pseudoClass->mType); EventStates statesToCheck = sPseudoClassStates[idx]; if (!statesToCheck.IsEmpty() && !StateSelectorMatches(aElement, aSelector, aNodeMatchContext, aTreeMatchContext, aSelectorFlags, nullptr, statesToCheck)) { return false; } } return true; } // |aDependence| has two functions: // * when non-null, it indicates that we're processing a negation, // which is done only when SelectorMatches calls itself recursively // * what it points to should be set to true whenever a test is skipped // because of aNodeMatchContent.mStateMask static bool SelectorMatches(Element* aElement, nsCSSSelector* aSelector, NodeMatchContext& aNodeMatchContext, TreeMatchContext& aTreeMatchContext, SelectorMatchesFlags aSelectorFlags, bool* const aDependence = nullptr) { NS_PRECONDITION(!aSelector->IsPseudoElement(), "Pseudo-element snuck into SelectorMatches?"); MOZ_ASSERT(aTreeMatchContext.mForStyling || !aNodeMatchContext.mIsRelevantLink, "mIsRelevantLink should be set to false when mForStyling " "is false since we don't know how to set it correctly in " "Has(Attribute|State)DependentStyle"); // namespace/tag match // optimization : bail out early if we can if ((kNameSpaceID_Unknown != aSelector->mNameSpace && aElement->GetNameSpaceID() != aSelector->mNameSpace)) return false; if (aSelector->mLowercaseTag) { nsIAtom* selectorTag = (aTreeMatchContext.mIsHTMLDocument && aElement->IsHTMLElement()) ? aSelector->mLowercaseTag : aSelector->mCasedTag; if (selectorTag != aElement->NodeInfo()->NameAtom()) { return false; } } nsAtomList* IDList = aSelector->mIDList; if (IDList) { nsIAtom* id = aElement->GetID(); if (id) { // case sensitivity: bug 93371 const bool isCaseSensitive = aTreeMatchContext.mCompatMode != eCompatibility_NavQuirks; if (isCaseSensitive) { do { if (IDList->mAtom != id) { return false; } IDList = IDList->mNext; } while (IDList); } else { // Use EqualsIgnoreASCIICase instead of full on unicode case conversion // in order to save on performance. This is only used in quirks mode // anyway. nsDependentAtomString id1Str(id); do { if (!nsContentUtils::EqualsIgnoreASCIICase(id1Str, nsDependentAtomString(IDList->mAtom))) { return false; } IDList = IDList->mNext; } while (IDList); } } else { // Element has no id but we have an id selector return false; } } nsAtomList* classList = aSelector->mClassList; if (classList) { // test for class match const nsAttrValue *elementClasses = aElement->GetClasses(); if (!elementClasses) { // Element has no classes but we have a class selector return false; } // case sensitivity: bug 93371 const bool isCaseSensitive = aTreeMatchContext.mCompatMode != eCompatibility_NavQuirks; while (classList) { if (!elementClasses->Contains(classList->mAtom, isCaseSensitive ? eCaseMatters : eIgnoreCase)) { return false; } classList = classList->mNext; } } const bool isNegated = (aDependence != nullptr); // The selectors for which we set node bits are, unfortunately, early // in this function (because they're pseudo-classes, which are // generally quick to test, and thus earlier). If they were later, // we'd probably avoid setting those bits in more cases where setting // them is unnecessary. NS_ASSERTION(aNodeMatchContext.mStateMask.IsEmpty() || !aTreeMatchContext.mForStyling, "mForStyling must be false if we're just testing for " "state-dependence"); // test for pseudo class match for (nsPseudoClassList* pseudoClass = aSelector->mPseudoClassList; pseudoClass; pseudoClass = pseudoClass->mNext) { auto idx = static_cast<CSSPseudoClassTypeBase>(pseudoClass->mType); EventStates statesToCheck = sPseudoClassStates[idx]; if (statesToCheck.IsEmpty()) { // keep the cases here in the same order as the list in // nsCSSPseudoClassList.h switch (pseudoClass->mType) { case CSSPseudoClassType::empty: if (!checkGenericEmptyMatches(aElement, aTreeMatchContext, true)) { return false; } break; case CSSPseudoClassType::mozOnlyWhitespace: if (!checkGenericEmptyMatches(aElement, aTreeMatchContext, false)) { return false; } break; case CSSPseudoClassType::mozEmptyExceptChildrenWithLocalname: { NS_ASSERTION(pseudoClass->u.mString, "Must have string!"); nsIContent *child = nullptr; int32_t index = -1; if (aTreeMatchContext.mForStyling) // FIXME: This isn't sufficient to handle: // :-moz-empty-except-children-with-localname() + E // :-moz-empty-except-children-with-localname() ~ E // because we don't know to restyle the grandparent of the // inserted/removed element (as in bug 534804 for :empty). aElement->SetFlags(NODE_HAS_SLOW_SELECTOR); do { child = aElement->GetChildAt(++index); } while (child && (!IsSignificantChild(child, true, false) || (child->GetNameSpaceID() == aElement->GetNameSpaceID() && child->NodeInfo()->NameAtom()->Equals(nsDependentString(pseudoClass->u.mString))))); if (child != nullptr) { return false; } } break; case CSSPseudoClassType::lang: { NS_ASSERTION(nullptr != pseudoClass->u.mString, "null lang parameter"); if (!pseudoClass->u.mString || !*pseudoClass->u.mString) { return false; } // We have to determine the language of the current element. Since // this is currently no property and since the language is inherited // from the parent we have to be prepared to look at all parent // nodes. The language itself is encoded in the LANG attribute. nsAutoString language; if (aElement->GetLang(language)) { if (!nsStyleUtil::DashMatchCompare(language, nsDependentString(pseudoClass->u.mString), nsASCIICaseInsensitiveStringComparator())) { return false; } // This pseudo-class matched; move on to the next thing break; } nsIDocument* doc = aTreeMatchContext.mDocument; if (doc) { // Try to get the language from the HTTP header or if this // is missing as well from the preferences. // The content language can be a comma-separated list of // language codes. doc->GetContentLanguage(language); nsDependentString langString(pseudoClass->u.mString); language.StripWhitespace(); int32_t begin = 0; int32_t len = language.Length(); while (begin < len) { int32_t end = language.FindChar(char16_t(','), begin); if (end == kNotFound) { end = len; } if (nsStyleUtil::DashMatchCompare(Substring(language, begin, end-begin), langString, nsASCIICaseInsensitiveStringComparator())) { break; } begin = end + 1; } if (begin < len) { // This pseudo-class matched break; } } } return false; case CSSPseudoClassType::mozBoundElement: if (aTreeMatchContext.mScopedRoot != aElement) { return false; } break; case CSSPseudoClassType::root: if (aElement != aElement->OwnerDoc()->GetRootElement()) { return false; } break; case CSSPseudoClassType::any: { nsCSSSelectorList *l; for (l = pseudoClass->u.mSelectors; l; l = l->mNext) { nsCSSSelector *s = l->mSelectors; MOZ_ASSERT(!s->mNext && !s->IsPseudoElement(), "parser failed"); if (SelectorMatches( aElement, s, aNodeMatchContext, aTreeMatchContext, SelectorMatchesFlags::IS_PSEUDO_CLASS_ARGUMENT)) { break; } } if (!l) { return false; } } break; case CSSPseudoClassType::firstChild: if (!edgeChildMatches(aElement, aTreeMatchContext, true, false)) { return false; } break; case CSSPseudoClassType::firstNode: { nsIContent *firstNode = nullptr; nsIContent *parent = aElement->GetParent(); if (parent) { if (aTreeMatchContext.mForStyling) parent->SetFlags(NODE_HAS_EDGE_CHILD_SELECTOR); int32_t index = -1; do { firstNode = parent->GetChildAt(++index); // stop at first non-comment and non-whitespace node } while (firstNode && !IsSignificantChild(firstNode, true, false)); } if (aElement != firstNode) { return false; } } break; case CSSPseudoClassType::lastChild: if (!edgeChildMatches(aElement, aTreeMatchContext, false, true)) { return false; } break; case CSSPseudoClassType::lastNode: { nsIContent *lastNode = nullptr; nsIContent *parent = aElement->GetParent(); if (parent) { if (aTreeMatchContext.mForStyling) parent->SetFlags(NODE_HAS_EDGE_CHILD_SELECTOR); uint32_t index = parent->GetChildCount(); do { lastNode = parent->GetChildAt(--index); // stop at first non-comment and non-whitespace node } while (lastNode && !IsSignificantChild(lastNode, true, false)); } if (aElement != lastNode) { return false; } } break; case CSSPseudoClassType::onlyChild: if (!edgeChildMatches(aElement, aTreeMatchContext, true, true)) { return false; } break; case CSSPseudoClassType::firstOfType: if (!edgeOfTypeMatches(aElement, aTreeMatchContext, true, false)) { return false; } break; case CSSPseudoClassType::lastOfType: if (!edgeOfTypeMatches(aElement, aTreeMatchContext, false, true)) { return false; } break; case CSSPseudoClassType::onlyOfType: if (!edgeOfTypeMatches(aElement, aTreeMatchContext, true, true)) { return false; } break; case CSSPseudoClassType::nthChild: if (!nthChildGenericMatches(aElement, aTreeMatchContext, pseudoClass, false, false)) { return false; } break; case CSSPseudoClassType::nthLastChild: if (!nthChildGenericMatches(aElement, aTreeMatchContext, pseudoClass, false, true)) { return false; } break; case CSSPseudoClassType::nthOfType: if (!nthChildGenericMatches(aElement, aTreeMatchContext, pseudoClass, true, false)) { return false; } break; case CSSPseudoClassType::nthLastOfType: if (!nthChildGenericMatches(aElement, aTreeMatchContext, pseudoClass, true, true)) { return false; } break; case CSSPseudoClassType::mozIsHTML: if (!aTreeMatchContext.mIsHTMLDocument || !aElement->IsHTMLElement()) { return false; } break; case CSSPseudoClassType::mozNativeAnonymous: if (!aElement->IsInNativeAnonymousSubtree()) { return false; } break; case CSSPseudoClassType::mozSystemMetric: { nsCOMPtr<nsIAtom> metric = NS_Atomize(pseudoClass->u.mString); if (!nsCSSRuleProcessor::HasSystemMetric(metric)) { return false; } } break; case CSSPseudoClassType::mozLocaleDir: { bool docIsRTL = aTreeMatchContext.mDocument->GetDocumentState(). HasState(NS_DOCUMENT_STATE_RTL_LOCALE); nsDependentString dirString(pseudoClass->u.mString); if (dirString.EqualsLiteral("rtl")) { if (!docIsRTL) { return false; } } else if (dirString.EqualsLiteral("ltr")) { if (docIsRTL) { return false; } } else { // Selectors specifying other directions never match. return false; } } break; case CSSPseudoClassType::mozLWTheme: { if (aTreeMatchContext.mDocument->GetDocumentLWTheme() <= nsIDocument::Doc_Theme_None) { return false; } } break; case CSSPseudoClassType::mozLWThemeBrightText: { if (aTreeMatchContext.mDocument->GetDocumentLWTheme() != nsIDocument::Doc_Theme_Bright) { return false; } } break; case CSSPseudoClassType::mozLWThemeDarkText: { if (aTreeMatchContext.mDocument->GetDocumentLWTheme() != nsIDocument::Doc_Theme_Dark) { return false; } } break; case CSSPseudoClassType::mozWindowInactive: if (!aTreeMatchContext.mDocument->GetDocumentState(). HasState(NS_DOCUMENT_STATE_WINDOW_INACTIVE)) { return false; } break; case CSSPseudoClassType::mozTableBorderNonzero: { if (!aElement->IsHTMLElement(nsGkAtoms::table)) { return false; } const nsAttrValue *val = aElement->GetParsedAttr(nsGkAtoms::border); if (!val || (val->Type() == nsAttrValue::eInteger && val->GetIntegerValue() == 0)) { return false; } } break; case CSSPseudoClassType::mozBrowserFrame: { nsCOMPtr<nsIMozBrowserFrame> browserFrame = do_QueryInterface(aElement); if (!browserFrame || !browserFrame->GetReallyIsBrowserOrApp()) { return false; } } break; case CSSPseudoClassType::mozDir: case CSSPseudoClassType::dir: { if (aDependence) { EventStates states = sPseudoClassStateDependences[ static_cast<CSSPseudoClassTypeBase>(pseudoClass->mType)]; if (aNodeMatchContext.mStateMask.HasAtLeastOneOfStates(states)) { *aDependence = true; return false; } } // If we only had to consider HTML, directionality would be // exclusively LTR or RTL. // // However, in markup languages where there is no direction attribute // we have to consider the possibility that neither dir(rtl) nor // dir(ltr) matches. EventStates state = aElement->StyleState(); nsDependentString dirString(pseudoClass->u.mString); if (dirString.EqualsLiteral("rtl")) { if (!state.HasState(NS_EVENT_STATE_RTL)) { return false; } } else if (dirString.EqualsLiteral("ltr")) { if (!state.HasState(NS_EVENT_STATE_LTR)) { return false; } } else { // Selectors specifying other directions never match. return false; } } break; case CSSPseudoClassType::scope: if (aTreeMatchContext.mForScopedStyle) { if (aTreeMatchContext.mCurrentStyleScope) { // If mCurrentStyleScope is null, aElement must be the style // scope root. This is because the PopStyleScopeForSelectorMatching // call in SelectorMatchesTree sets mCurrentStyleScope to null // as soon as we visit the style scope element, and we won't // progress further up the tree after this call to // SelectorMatches. Thus if mCurrentStyleScope is still set, // we know the selector does not match. return false; } } else if (aTreeMatchContext.HasSpecifiedScope()) { if (!aTreeMatchContext.IsScopeElement(aElement)) { return false; } } else { if (aElement != aElement->OwnerDoc()->GetRootElement()) { return false; } } break; default: MOZ_ASSERT(false, "How did that happen?"); } } else { if (!StateSelectorMatches(aElement, aSelector, aNodeMatchContext, aTreeMatchContext, aSelectorFlags, aDependence, statesToCheck)) { return false; } } } bool result = true; if (aSelector->mAttrList) { // test for attribute match if (!aElement->HasAttrs()) { // if no attributes on the content, no match return false; } else { result = true; nsAttrSelector* attr = aSelector->mAttrList; nsIAtom* matchAttribute; do { bool isHTML = (aTreeMatchContext.mIsHTMLDocument && aElement->IsHTMLElement()); matchAttribute = isHTML ? attr->mLowercaseAttr : attr->mCasedAttr; if (attr->mNameSpace == kNameSpaceID_Unknown) { // Attr selector with a wildcard namespace. We have to examine all // the attributes on our content node.... This sort of selector is // essentially a boolean OR, over all namespaces, of equivalent attr // selectors with those namespaces. So to evaluate whether it // matches, evaluate for each namespace (the only namespaces that // have a chance at matching, of course, are ones that the element // actually has attributes in), short-circuiting if we ever match. result = false; const nsAttrName* attrName; for (uint32_t i = 0; (attrName = aElement->GetAttrNameAt(i)); ++i) { if (attrName->LocalName() != matchAttribute) { continue; } if (attr->mFunction == NS_ATTR_FUNC_SET) { result = true; } else { nsAutoString value; #ifdef DEBUG bool hasAttr = #endif aElement->GetAttr(attrName->NamespaceID(), attrName->LocalName(), value); NS_ASSERTION(hasAttr, "GetAttrNameAt lied"); result = AttrMatchesValue(attr, value, isHTML); } // At this point |result| has been set by us // explicitly in this loop. If it's false, we may still match // -- the content may have another attribute with the same name but // in a different namespace. But if it's true, we are done (we // can short-circuit the boolean OR described above). if (result) { break; } } } else if (attr->mFunction == NS_ATTR_FUNC_EQUALS) { result = aElement-> AttrValueIs(attr->mNameSpace, matchAttribute, attr->mValue, attr->IsValueCaseSensitive(isHTML) ? eCaseMatters : eIgnoreCase); } else if (!aElement->HasAttr(attr->mNameSpace, matchAttribute)) { result = false; } else if (attr->mFunction != NS_ATTR_FUNC_SET) { nsAutoString value; #ifdef DEBUG bool hasAttr = #endif aElement->GetAttr(attr->mNameSpace, matchAttribute, value); NS_ASSERTION(hasAttr, "HasAttr lied"); result = AttrMatchesValue(attr, value, isHTML); } attr = attr->mNext; } while (attr && result); } } // apply SelectorMatches to the negated selectors in the chain if (!isNegated) { for (nsCSSSelector *negation = aSelector->mNegations; result && negation; negation = negation->mNegations) { bool dependence = false; result = !SelectorMatches(aElement, negation, aNodeMatchContext, aTreeMatchContext, SelectorMatchesFlags::IS_PSEUDO_CLASS_ARGUMENT, &dependence); // If the selector does match due to the dependence on // aNodeMatchContext.mStateMask, then we want to keep result true // so that the final result of SelectorMatches is true. Doing so // tells StateEnumFunc that there is a dependence on the state. result = result || dependence; } } return result; } #undef STATE_CHECK #ifdef DEBUG static bool HasPseudoClassSelectorArgsWithCombinators(nsCSSSelector* aSelector) { for (nsPseudoClassList* p = aSelector->mPseudoClassList; p; p = p->mNext) { if (nsCSSPseudoClasses::HasSelectorListArg(p->mType)) { for (nsCSSSelectorList* l = p->u.mSelectors; l; l = l->mNext) { if (l->mSelectors->mNext) { return true; } } } } for (nsCSSSelector* n = aSelector->mNegations; n; n = n->mNegations) { if (n->mNext) { return true; } } return false; } #endif /* static */ bool nsCSSRuleProcessor::RestrictedSelectorMatches( Element* aElement, nsCSSSelector* aSelector, TreeMatchContext& aTreeMatchContext) { MOZ_ASSERT(aSelector->IsRestrictedSelector(), "aSelector must not have a pseudo-element"); NS_WARNING_ASSERTION( !HasPseudoClassSelectorArgsWithCombinators(aSelector), "processing eRestyle_SomeDescendants can be slow if pseudo-classes with " "selector arguments can now have combinators in them"); // We match aSelector as if :visited and :link both match visited and // unvisited links. NodeMatchContext nodeContext(EventStates(), nsCSSRuleProcessor::IsLink(aElement)); if (nodeContext.mIsRelevantLink) { aTreeMatchContext.SetHaveRelevantLink(); } aTreeMatchContext.ResetForUnvisitedMatching(); bool matches = SelectorMatches(aElement, aSelector, nodeContext, aTreeMatchContext, SelectorMatchesFlags::NONE); if (nodeContext.mIsRelevantLink) { aTreeMatchContext.ResetForVisitedMatching(); if (SelectorMatches(aElement, aSelector, nodeContext, aTreeMatchContext, SelectorMatchesFlags::NONE)) { matches = true; } } return matches; } // Right now, there are four operators: // ' ', the descendant combinator, is greedy // '~', the indirect adjacent sibling combinator, is greedy // '+' and '>', the direct adjacent sibling and child combinators, are not #define NS_IS_GREEDY_OPERATOR(ch) \ ((ch) == char16_t(' ') || (ch) == char16_t('~')) /** * Flags for SelectorMatchesTree. */ enum SelectorMatchesTreeFlags { // Whether we still have not found the closest ancestor link element and // thus have to check the current element for it. eLookForRelevantLink = 0x1, // Whether SelectorMatchesTree should check for, and return true upon // finding, an ancestor element that has an eRestyle_SomeDescendants // restyle hint pending. eMatchOnConditionalRestyleAncestor = 0x2, }; static bool SelectorMatchesTree(Element* aPrevElement, nsCSSSelector* aSelector, TreeMatchContext& aTreeMatchContext, SelectorMatchesTreeFlags aFlags) { MOZ_ASSERT(!aSelector || !aSelector->IsPseudoElement()); nsCSSSelector* selector = aSelector; Element* prevElement = aPrevElement; while (selector) { // check compound selectors NS_ASSERTION(!selector->mNext || selector->mNext->mOperator != char16_t(0), "compound selector without combinator"); // If after the previous selector match we are now outside the // current style scope, we don't need to match any further. if (aTreeMatchContext.mForScopedStyle && !aTreeMatchContext.IsWithinStyleScopeForSelectorMatching()) { return false; } // for adjacent sibling combinators, the content to test against the // selector is the previous sibling *element* Element* element = nullptr; if (char16_t('+') == selector->mOperator || char16_t('~') == selector->mOperator) { // The relevant link must be an ancestor of the node being matched. aFlags = SelectorMatchesTreeFlags(aFlags & ~eLookForRelevantLink); nsIContent* parent = prevElement->GetParent(); if (parent) { if (aTreeMatchContext.mForStyling) parent->SetFlags(NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS); element = prevElement->GetPreviousElementSibling(); } } // for descendant combinators and child combinators, the element // to test against is the parent else { nsIContent *content = prevElement->GetParent(); // GetParent could return a document fragment; we only want // element parents. if (content && content->IsElement()) { element = content->AsElement(); if (aTreeMatchContext.mForScopedStyle) { // We are moving up to the parent element; tell the // TreeMatchContext, so that in case this element is the // style scope element, selector matching stops before we // traverse further up the tree. aTreeMatchContext.PopStyleScopeForSelectorMatching(element); } // Compatibility hack: First try matching this selector as though the // <xbl:children> element wasn't in the tree to allow old selectors // were written before <xbl:children> participated in CSS selector // matching to work. if (selector->mOperator == '>' && element->IsActiveChildrenElement()) { Element* styleScope = aTreeMatchContext.mCurrentStyleScope; if (SelectorMatchesTree(element, selector, aTreeMatchContext, aFlags)) { // It matched, don't try matching on the <xbl:children> element at // all. return true; } // We want to reset mCurrentStyleScope on aTreeMatchContext // back to its state before the SelectorMatchesTree call, in // case that call happens to traverse past the style scope element // and sets it to null. aTreeMatchContext.mCurrentStyleScope = styleScope; } } } if (!element) { return false; } if ((aFlags & eMatchOnConditionalRestyleAncestor) && element->HasFlag(ELEMENT_IS_CONDITIONAL_RESTYLE_ANCESTOR)) { // If we're looking at an element that we already generated an // eRestyle_SomeDescendants restyle hint for, then we should pretend // that we matched here, because we don't know what the values of // attributes on |element| were at the time we generated the // eRestyle_SomeDescendants. This causes AttributeEnumFunc and // HasStateDependentStyle below to generate a restyle hint for the // change we're currently looking at, as we don't know whether the LHS // of the selector we looked up matches or not. (We only pass in aFlags // to cause us to look for eRestyle_SomeDescendants here under // AttributeEnumFunc and HasStateDependentStyle.) return true; } const bool isRelevantLink = (aFlags & eLookForRelevantLink) && nsCSSRuleProcessor::IsLink(element); NodeMatchContext nodeContext(EventStates(), isRelevantLink); if (isRelevantLink) { // If we find an ancestor of the matched node that is a link // during the matching process, then it's the relevant link (see // constructor call above). // Since we are still matching against selectors that contain // :visited (they'll just fail), we will always find such a node // during the selector matching process if there is a relevant // link that can influence selector matching. aFlags = SelectorMatchesTreeFlags(aFlags & ~eLookForRelevantLink); aTreeMatchContext.SetHaveRelevantLink(); } if (SelectorMatches(element, selector, nodeContext, aTreeMatchContext, SelectorMatchesFlags::NONE)) { // to avoid greedy matching, we need to recur if this is a // descendant or general sibling combinator and the next // combinator is different, but we can make an exception for // sibling, then parent, since a sibling's parent is always the // same. if (NS_IS_GREEDY_OPERATOR(selector->mOperator) && selector->mNext && selector->mNext->mOperator != selector->mOperator && !(selector->mOperator == '~' && NS_IS_ANCESTOR_OPERATOR(selector->mNext->mOperator))) { // pretend the selector didn't match, and step through content // while testing the same selector // This approach is slightly strange in that when it recurs // it tests from the top of the content tree, down. This // doesn't matter much for performance since most selectors // don't match. (If most did, it might be faster...) Element* styleScope = aTreeMatchContext.mCurrentStyleScope; if (SelectorMatchesTree(element, selector, aTreeMatchContext, aFlags)) { return true; } // We want to reset mCurrentStyleScope on aTreeMatchContext // back to its state before the SelectorMatchesTree call, in // case that call happens to traverse past the style scope element // and sets it to null. aTreeMatchContext.mCurrentStyleScope = styleScope; } selector = selector->mNext; } else { // for adjacent sibling and child combinators, if we didn't find // a match, we're done if (!NS_IS_GREEDY_OPERATOR(selector->mOperator)) { return false; // parent was required to match } } prevElement = element; } return true; // all the selectors matched. } static inline void ContentEnumFunc(const RuleValue& value, nsCSSSelector* aSelector, ElementDependentRuleProcessorData* data, NodeMatchContext& nodeContext, AncestorFilter *ancestorFilter) { if (nodeContext.mIsRelevantLink) { data->mTreeMatchContext.SetHaveRelevantLink(); } if (ancestorFilter && !ancestorFilter->MightHaveMatchingAncestor<RuleValue::eMaxAncestorHashes>( value.mAncestorSelectorHashes)) { // We won't match; nothing else to do here return; } if (!data->mTreeMatchContext.SetStyleScopeForSelectorMatching(data->mElement, data->mScope)) { // The selector is for a rule in a scoped style sheet, and the subject // of the selector matching is not in its scope. return; } nsCSSSelector* selector = aSelector; if (selector->IsPseudoElement()) { PseudoElementRuleProcessorData* pdata = static_cast<PseudoElementRuleProcessorData*>(data); if (!pdata->mPseudoElement && selector->mPseudoClassList) { // We can get here when calling getComputedStyle(aElt, aPseudo) if: // // * aPseudo is a pseudo-element that supports a user action // pseudo-class, like "::placeholder"; // * there is a style rule that uses a pseudo-class on this // pseudo-element in the document, like ::placeholder:hover; and // * aElt does not have such a pseudo-element. // // We know that the selector can't match, since there is no element for // the user action pseudo-class to match against. return; } if (!StateSelectorMatches(pdata->mPseudoElement, aSelector, nodeContext, data->mTreeMatchContext, SelectorMatchesFlags::NONE)) { return; } selector = selector->mNext; } SelectorMatchesFlags selectorFlags = SelectorMatchesFlags::NONE; if (aSelector->IsPseudoElement()) { selectorFlags |= SelectorMatchesFlags::HAS_PSEUDO_ELEMENT; } if (SelectorMatches(data->mElement, selector, nodeContext, data->mTreeMatchContext, selectorFlags)) { nsCSSSelector *next = selector->mNext; if (!next || SelectorMatchesTree(data->mElement, next, data->mTreeMatchContext, nodeContext.mIsRelevantLink ? SelectorMatchesTreeFlags(0) : eLookForRelevantLink)) { css::Declaration* declaration = value.mRule->GetDeclaration(); declaration->SetImmutable(); data->mRuleWalker->Forward(declaration); // nsStyleSet will deal with the !important rule } } } /* virtual */ void nsCSSRuleProcessor::RulesMatching(ElementRuleProcessorData *aData) { RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); if (cascade) { NodeMatchContext nodeContext(EventStates(), nsCSSRuleProcessor::IsLink(aData->mElement)); cascade->mRuleHash.EnumerateAllRules(aData->mElement, aData, nodeContext); } } /* virtual */ void nsCSSRuleProcessor::RulesMatching(PseudoElementRuleProcessorData* aData) { RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); if (cascade) { RuleHash* ruleHash = cascade->mPseudoElementRuleHashes[ static_cast<CSSPseudoElementTypeBase>(aData->mPseudoType)]; if (ruleHash) { NodeMatchContext nodeContext(EventStates(), nsCSSRuleProcessor::IsLink(aData->mElement)); ruleHash->EnumerateAllRules(aData->mElement, aData, nodeContext); } } } /* virtual */ void nsCSSRuleProcessor::RulesMatching(AnonBoxRuleProcessorData* aData) { RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); if (cascade && cascade->mAnonBoxRules.EntryCount()) { auto entry = static_cast<RuleHashTagTableEntry*> (cascade->mAnonBoxRules.Search(aData->mPseudoTag)); if (entry) { nsTArray<RuleValue>& rules = entry->mRules; for (RuleValue *value = rules.Elements(), *end = value + rules.Length(); value != end; ++value) { css::Declaration* declaration = value->mRule->GetDeclaration(); declaration->SetImmutable(); aData->mRuleWalker->Forward(declaration); } } } } #ifdef MOZ_XUL /* virtual */ void nsCSSRuleProcessor::RulesMatching(XULTreeRuleProcessorData* aData) { RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); if (cascade && cascade->mXULTreeRules.EntryCount()) { auto entry = static_cast<RuleHashTagTableEntry*> (cascade->mXULTreeRules.Search(aData->mPseudoTag)); if (entry) { NodeMatchContext nodeContext(EventStates(), nsCSSRuleProcessor::IsLink(aData->mElement)); nsTArray<RuleValue>& rules = entry->mRules; for (RuleValue *value = rules.Elements(), *end = value + rules.Length(); value != end; ++value) { if (aData->mComparator->PseudoMatches(value->mSelector)) { ContentEnumFunc(*value, value->mSelector->mNext, aData, nodeContext, nullptr); } } } } } #endif static inline nsRestyleHint RestyleHintForOp(char16_t oper) { if (oper == char16_t('+') || oper == char16_t('~')) { return eRestyle_LaterSiblings; } if (oper != char16_t(0)) { return eRestyle_Subtree; } return eRestyle_Self; } nsRestyleHint nsCSSRuleProcessor::HasStateDependentStyle(ElementDependentRuleProcessorData* aData, Element* aStatefulElement, CSSPseudoElementType aPseudoType, EventStates aStateMask) { MOZ_ASSERT(!aData->mTreeMatchContext.mForScopedStyle, "mCurrentStyleScope will need to be saved and restored after the " "SelectorMatchesTree call"); bool isPseudoElement = aPseudoType != CSSPseudoElementType::NotPseudo; RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); // Look up the content node in the state rule list, which points to // any (CSS2 definition) simple selector (whether or not it is the // subject) that has a state pseudo-class on it. This means that this // code will be matching selectors that aren't real selectors in any // stylesheet (e.g., if there is a selector "body > p:hover > a", then // "body > p:hover" will be in |cascade->mStateSelectors|). Note that // |ComputeSelectorStateDependence| below determines which selectors are in // |cascade->mStateSelectors|. nsRestyleHint hint = nsRestyleHint(0); if (cascade) { StateSelector *iter = cascade->mStateSelectors.Elements(), *end = iter + cascade->mStateSelectors.Length(); NodeMatchContext nodeContext(aStateMask, false); for(; iter != end; ++iter) { nsCSSSelector* selector = iter->mSelector; EventStates states = iter->mStates; if (selector->IsPseudoElement() != isPseudoElement) { continue; } nsCSSSelector* selectorForPseudo; if (isPseudoElement) { if (selector->PseudoType() != aPseudoType) { continue; } selectorForPseudo = selector; selector = selector->mNext; } nsRestyleHint possibleChange = RestyleHintForOp(selector->mOperator); SelectorMatchesFlags selectorFlags = SelectorMatchesFlags::UNKNOWN; // If hint already includes all the bits of possibleChange, // don't bother calling SelectorMatches, since even if it returns false // hint won't change. // Also don't bother calling SelectorMatches if none of the // states passed in are relevant here. if ((possibleChange & ~hint) && states.HasAtLeastOneOfStates(aStateMask) && // We can optimize away testing selectors that only involve :hover, a // namespace, and a tag name against nodes that don't have the // NodeHasRelevantHoverRules flag: such a selector didn't match // the tag name or namespace the first time around (since the :hover // didn't set the NodeHasRelevantHoverRules flag), so it won't // match it now. Check for our selector only having :hover states, or // the element having the hover rules flag, or the selector having // some sort of non-namespace, non-tagname data in it. (states != NS_EVENT_STATE_HOVER || aStatefulElement->HasRelevantHoverRules() || selector->mIDList || selector->mClassList || // We generally expect an mPseudoClassList, since we have a :hover. // The question is whether we have anything else in there. (selector->mPseudoClassList && (selector->mPseudoClassList->mNext || selector->mPseudoClassList->mType != CSSPseudoClassType::hover)) || selector->mAttrList || selector->mNegations) && (!isPseudoElement || StateSelectorMatches(aStatefulElement, selectorForPseudo, nodeContext, aData->mTreeMatchContext, selectorFlags, nullptr, aStateMask)) && SelectorMatches(aData->mElement, selector, nodeContext, aData->mTreeMatchContext, selectorFlags) && SelectorMatchesTree(aData->mElement, selector->mNext, aData->mTreeMatchContext, eMatchOnConditionalRestyleAncestor)) { hint = nsRestyleHint(hint | possibleChange); } } } return hint; } nsRestyleHint nsCSSRuleProcessor::HasStateDependentStyle(StateRuleProcessorData* aData) { return HasStateDependentStyle(aData, aData->mElement, CSSPseudoElementType::NotPseudo, aData->mStateMask); } nsRestyleHint nsCSSRuleProcessor::HasStateDependentStyle(PseudoElementStateRuleProcessorData* aData) { return HasStateDependentStyle(aData, aData->mPseudoElement, aData->mPseudoType, aData->mStateMask); } bool nsCSSRuleProcessor::HasDocumentStateDependentStyle(StateRuleProcessorData* aData) { RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); return cascade && cascade->mSelectorDocumentStates.HasAtLeastOneOfStates(aData->mStateMask); } struct AttributeEnumData { AttributeEnumData(AttributeRuleProcessorData *aData, RestyleHintData& aRestyleHintData) : data(aData), change(nsRestyleHint(0)), hintData(aRestyleHintData) {} AttributeRuleProcessorData *data; nsRestyleHint change; RestyleHintData& hintData; }; static inline nsRestyleHint RestyleHintForSelectorWithAttributeChange(nsRestyleHint aCurrentHint, nsCSSSelector* aSelector, nsCSSSelector* aRightmostSelector) { MOZ_ASSERT(aSelector); char16_t oper = aSelector->mOperator; if (oper == char16_t('+') || oper == char16_t('~')) { return eRestyle_LaterSiblings; } if (oper == char16_t(':')) { return eRestyle_Subtree; } if (oper != char16_t(0)) { // Check whether the selector is in a form that supports // eRestyle_SomeDescendants. If it isn't, return eRestyle_Subtree. if (aCurrentHint & eRestyle_Subtree) { // No point checking, since we'll end up restyling the whole // subtree anyway. return eRestyle_Subtree; } if (!aRightmostSelector) { // aSelector wasn't a top-level selector, which means we were inside // a :not() or :-moz-any(). We don't support that. return eRestyle_Subtree; } MOZ_ASSERT(aSelector != aRightmostSelector, "if aSelector == aRightmostSelector then we should have " "no operator"); // Check that aRightmostSelector can be passed to RestrictedSelectorMatches. if (!aRightmostSelector->IsRestrictedSelector()) { return eRestyle_Subtree; } // We also don't support pseudo-elements on any of the selectors // between aRightmostSelector and aSelector. // XXX Can we lift this restriction, so that we don't have to loop // over all the selectors? for (nsCSSSelector* sel = aRightmostSelector->mNext; sel != aSelector; sel = sel->mNext) { MOZ_ASSERT(sel, "aSelector must be reachable from aRightmostSelector"); if (sel->PseudoType() != CSSPseudoElementType::NotPseudo) { return eRestyle_Subtree; } } return eRestyle_SomeDescendants; } return eRestyle_Self; } static void AttributeEnumFunc(nsCSSSelector* aSelector, nsCSSSelector* aRightmostSelector, AttributeEnumData* aData) { AttributeRuleProcessorData *data = aData->data; if (!data->mTreeMatchContext.SetStyleScopeForSelectorMatching(data->mElement, data->mScope)) { // The selector is for a rule in a scoped style sheet, and the subject // of the selector matching is not in its scope. return; } nsRestyleHint possibleChange = RestyleHintForSelectorWithAttributeChange(aData->change, aSelector, aRightmostSelector); // If, ignoring eRestyle_SomeDescendants, enumData->change already includes // all the bits of possibleChange, don't bother calling SelectorMatches, since // even if it returns false enumData->change won't change. If possibleChange // has eRestyle_SomeDescendants, we need to call SelectorMatches(Tree) // regardless as it might give us new selectors to append to // mSelectorsForDescendants. NodeMatchContext nodeContext(EventStates(), false); if (((possibleChange & (~(aData->change) | eRestyle_SomeDescendants))) && SelectorMatches(data->mElement, aSelector, nodeContext, data->mTreeMatchContext, SelectorMatchesFlags::UNKNOWN) && SelectorMatchesTree(data->mElement, aSelector->mNext, data->mTreeMatchContext, eMatchOnConditionalRestyleAncestor)) { aData->change = nsRestyleHint(aData->change | possibleChange); if (possibleChange & eRestyle_SomeDescendants) { aData->hintData.mSelectorsForDescendants.AppendElement(aRightmostSelector); } } } static MOZ_ALWAYS_INLINE void EnumerateSelectors(nsTArray<SelectorPair>& aSelectors, AttributeEnumData* aData) { SelectorPair *iter = aSelectors.Elements(), *end = iter + aSelectors.Length(); for (; iter != end; ++iter) { AttributeEnumFunc(iter->mSelector, iter->mRightmostSelector, aData); } } static MOZ_ALWAYS_INLINE void EnumerateSelectors(nsTArray<nsCSSSelector*>& aSelectors, AttributeEnumData* aData) { nsCSSSelector **iter = aSelectors.Elements(), **end = iter + aSelectors.Length(); for (; iter != end; ++iter) { AttributeEnumFunc(*iter, nullptr, aData); } } nsRestyleHint nsCSSRuleProcessor::HasAttributeDependentStyle( AttributeRuleProcessorData* aData, RestyleHintData& aRestyleHintDataResult) { // We could try making use of aData->mModType, but :not rules make it a bit // of a pain to do so... So just ignore it for now. AttributeEnumData data(aData, aRestyleHintDataResult); // Don't do our special handling of certain attributes if the attr // hasn't changed yet. if (aData->mAttrHasChanged) { // check for the lwtheme and lwthemetextcolor attribute on root XUL elements if ((aData->mAttribute == nsGkAtoms::lwtheme || aData->mAttribute == nsGkAtoms::lwthemetextcolor) && aData->mElement->GetNameSpaceID() == kNameSpaceID_XUL && aData->mElement == aData->mElement->OwnerDoc()->GetRootElement()) { data.change = nsRestyleHint(data.change | eRestyle_Subtree); } // We don't know the namespace of the attribute, and xml:lang applies to // all elements. If the lang attribute changes, we need to restyle our // whole subtree, since the :lang selector on our descendants can examine // our lang attribute. if (aData->mAttribute == nsGkAtoms::lang) { data.change = nsRestyleHint(data.change | eRestyle_Subtree); } } RuleCascadeData* cascade = GetRuleCascade(aData->mPresContext); // Since we get both before and after notifications for attributes, we // don't have to ignore aData->mAttribute while matching. Just check // whether we have selectors relevant to aData->mAttribute that we // match. If this is the before change notification, that will catch // rules we might stop matching; if the after change notification, the // ones we might have started matching. if (cascade) { if (aData->mAttribute == nsGkAtoms::id) { nsIAtom* id = aData->mElement->GetID(); if (id) { auto entry = static_cast<AtomSelectorEntry*>(cascade->mIdSelectors.Search(id)); if (entry) { EnumerateSelectors(entry->mSelectors, &data); } } EnumerateSelectors(cascade->mPossiblyNegatedIDSelectors, &data); } if (aData->mAttribute == nsGkAtoms::_class && aData->mNameSpaceID == kNameSpaceID_None) { const nsAttrValue* otherClasses = aData->mOtherValue; NS_ASSERTION(otherClasses || aData->mModType == nsIDOMMutationEvent::REMOVAL, "All class values should be StoresOwnData and parsed" "via Element::BeforeSetAttr, so available here"); // For WillChange, enumerate classes that will be removed to see which // rules apply before the change. // For Changed, enumerate classes that have been added to see which rules // apply after the change. // In both cases we're interested in the classes that are currently on // the element but not in mOtherValue. const nsAttrValue* elementClasses = aData->mElement->GetClasses(); if (elementClasses) { int32_t atomCount = elementClasses->GetAtomCount(); if (atomCount > 0) { nsTHashtable<nsPtrHashKey<nsIAtom>> otherClassesTable; if (otherClasses) { int32_t otherClassesCount = otherClasses->GetAtomCount(); for (int32_t i = 0; i < otherClassesCount; ++i) { otherClassesTable.PutEntry(otherClasses->AtomAt(i)); } } for (int32_t i = 0; i < atomCount; ++i) { nsIAtom* curClass = elementClasses->AtomAt(i); if (!otherClassesTable.Contains(curClass)) { auto entry = static_cast<AtomSelectorEntry*> (cascade->mClassSelectors.Search(curClass)); if (entry) { EnumerateSelectors(entry->mSelectors, &data); } } } } } EnumerateSelectors(cascade->mPossiblyNegatedClassSelectors, &data); } auto entry = static_cast<AtomSelectorEntry*> (cascade->mAttributeSelectors.Search(aData->mAttribute)); if (entry) { EnumerateSelectors(entry->mSelectors, &data); } } return data.change; } /* virtual */ bool nsCSSRuleProcessor::MediumFeaturesChanged(nsPresContext* aPresContext) { // We don't want to do anything if there aren't any sets of rules // cached yet, since we should not build the rule cascade too early // (e.g., before we know whether the quirk style sheet should be // enabled). And if there's nothing cached, it doesn't matter if // anything changed. But in the cases where it does matter, we've // cached a previous cache key to test against, instead of our current // rule cascades. See bug 448281 and bug 1089417. MOZ_ASSERT(!(mRuleCascades && mPreviousCacheKey)); RuleCascadeData *old = mRuleCascades; if (old) { RefreshRuleCascade(aPresContext); return (old != mRuleCascades); } if (mPreviousCacheKey) { // RefreshRuleCascade will get rid of mPreviousCacheKey anyway to // maintain the invariant that we can't have both an mRuleCascades // and an mPreviousCacheKey. But we need to hold it a little // longer. UniquePtr<nsMediaQueryResultCacheKey> previousCacheKey( Move(mPreviousCacheKey)); RefreshRuleCascade(aPresContext); // This test is a bit pessimistic since the cache key's operator== // just does list comparison rather than set comparison, but it // should catch all the cases we care about (i.e., where the cascade // order hasn't changed). Other cases will do a restyle anyway, so // we shouldn't need to worry about posting a second. return !mRuleCascades || // all sheets gone, but we had sheets before mRuleCascades->mCacheKey != *previousCacheKey; } return false; } UniquePtr<nsMediaQueryResultCacheKey> nsCSSRuleProcessor::CloneMQCacheKey() { MOZ_ASSERT(!(mRuleCascades && mPreviousCacheKey)); RuleCascadeData* c = mRuleCascades; if (!c) { // We might have an mPreviousCacheKey. It already comes from a call // to CloneMQCacheKey, so don't bother checking // HasFeatureConditions(). if (mPreviousCacheKey) { NS_ASSERTION(mPreviousCacheKey->HasFeatureConditions(), "we shouldn't have a previous cache key unless it has " "feature conditions"); return MakeUnique<nsMediaQueryResultCacheKey>(*mPreviousCacheKey); } return UniquePtr<nsMediaQueryResultCacheKey>(); } if (!c->mCacheKey.HasFeatureConditions()) { return UniquePtr<nsMediaQueryResultCacheKey>(); } return MakeUnique<nsMediaQueryResultCacheKey>(c->mCacheKey); } /* virtual */ size_t nsCSSRuleProcessor::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const { size_t n = 0; n += mSheets.ShallowSizeOfExcludingThis(aMallocSizeOf); for (RuleCascadeData* cascade = mRuleCascades; cascade; cascade = cascade->mNext) { n += cascade->SizeOfIncludingThis(aMallocSizeOf); } return n; } /* virtual */ size_t nsCSSRuleProcessor::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const { return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf); } // Append all the currently-active font face rules to aArray. Return // true for success and false for failure. bool nsCSSRuleProcessor::AppendFontFaceRules( nsPresContext *aPresContext, nsTArray<nsFontFaceRuleContainer>& aArray) { RuleCascadeData* cascade = GetRuleCascade(aPresContext); if (cascade) { if (!aArray.AppendElements(cascade->mFontFaceRules)) return false; } return true; } nsCSSKeyframesRule* nsCSSRuleProcessor::KeyframesRuleForName(nsPresContext* aPresContext, const nsString& aName) { RuleCascadeData* cascade = GetRuleCascade(aPresContext); if (cascade) { return cascade->mKeyframesRuleTable.Get(aName); } return nullptr; } nsCSSCounterStyleRule* nsCSSRuleProcessor::CounterStyleRuleForName(nsPresContext* aPresContext, const nsAString& aName) { RuleCascadeData* cascade = GetRuleCascade(aPresContext); if (cascade) { return cascade->mCounterStyleRuleTable.Get(aName); } return nullptr; } // Append all the currently-active page rules to aArray. Return // true for success and false for failure. bool nsCSSRuleProcessor::AppendPageRules( nsPresContext* aPresContext, nsTArray<nsCSSPageRule*>& aArray) { RuleCascadeData* cascade = GetRuleCascade(aPresContext); if (cascade) { if (!aArray.AppendElements(cascade->mPageRules)) { return false; } } return true; } bool nsCSSRuleProcessor::AppendFontFeatureValuesRules( nsPresContext *aPresContext, nsTArray<nsCSSFontFeatureValuesRule*>& aArray) { RuleCascadeData* cascade = GetRuleCascade(aPresContext); if (cascade) { if (!aArray.AppendElements(cascade->mFontFeatureValuesRules)) return false; } return true; } nsresult nsCSSRuleProcessor::ClearRuleCascades() { if (!mPreviousCacheKey) { mPreviousCacheKey = CloneMQCacheKey(); } // No need to remove the rule processor from the RuleProcessorCache here, // since CSSStyleSheet::ClearRuleCascades will have called // RuleProcessorCache::RemoveSheet() passing itself, which will catch // this rule processor (and any others for different @-moz-document // cache key results). MOZ_ASSERT(!RuleProcessorCache::HasRuleProcessor(this)); #ifdef DEBUG // For shared rule processors, if we've already gathered document // rules, then they will now be out of date. We don't actually need // them to be up-to-date (see the comment in RefreshRuleCascade), so // record their invalidity so we can assert if we try to use them. if (!mMustGatherDocumentRules) { mDocumentRulesAndCacheKeyValid = false; } #endif // We rely on our caller (perhaps indirectly) to do something that // will rebuild style data and the user font set (either // nsIPresShell::RestyleForCSSRuleChanges or // nsPresContext::RebuildAllStyleData). RuleCascadeData *data = mRuleCascades; mRuleCascades = nullptr; while (data) { RuleCascadeData *next = data->mNext; delete data; data = next; } return NS_OK; } // This function should return the set of states that this selector // depends on; this is used to implement HasStateDependentStyle. It // does NOT recur down into things like :not and :-moz-any. inline EventStates ComputeSelectorStateDependence(nsCSSSelector& aSelector) { EventStates states; for (nsPseudoClassList* pseudoClass = aSelector.mPseudoClassList; pseudoClass; pseudoClass = pseudoClass->mNext) { // Tree pseudo-elements overload mPseudoClassList for things that // aren't pseudo-classes. if (pseudoClass->mType >= CSSPseudoClassType::Count) { continue; } auto idx = static_cast<CSSPseudoClassTypeBase>(pseudoClass->mType); states |= sPseudoClassStateDependences[idx]; } return states; } static bool AddSelector(RuleCascadeData* aCascade, // The part between combinators at the top level of the selector nsCSSSelector* aSelectorInTopLevel, // The part we should look through (might be in :not or :-moz-any()) nsCSSSelector* aSelectorPart, // The right-most selector at the top level nsCSSSelector* aRightmostSelector) { // It's worth noting that this loop over negations isn't quite // optimal for two reasons. One, we could add something to one of // these lists twice, which means we'll check it twice, but I don't // think that's worth worrying about. (We do the same for multiple // attribute selectors on the same attribute.) Two, we don't really // need to check negations past the first in the current // implementation (and they're rare as well), but that might change // in the future if :not() is extended. for (nsCSSSelector* negation = aSelectorPart; negation; negation = negation->mNegations) { // Track both document states and attribute dependence in pseudo-classes. for (nsPseudoClassList* pseudoClass = negation->mPseudoClassList; pseudoClass; pseudoClass = pseudoClass->mNext) { switch (pseudoClass->mType) { case CSSPseudoClassType::mozLocaleDir: { aCascade->mSelectorDocumentStates |= NS_DOCUMENT_STATE_RTL_LOCALE; break; } case CSSPseudoClassType::mozWindowInactive: { aCascade->mSelectorDocumentStates |= NS_DOCUMENT_STATE_WINDOW_INACTIVE; break; } case CSSPseudoClassType::mozTableBorderNonzero: { nsTArray<SelectorPair> *array = aCascade->AttributeListFor(nsGkAtoms::border); if (!array) { return false; } array->AppendElement(SelectorPair(aSelectorInTopLevel, aRightmostSelector)); break; } default: { break; } } } // Build mStateSelectors. EventStates dependentStates = ComputeSelectorStateDependence(*negation); if (!dependentStates.IsEmpty()) { aCascade->mStateSelectors.AppendElement( nsCSSRuleProcessor::StateSelector(dependentStates, aSelectorInTopLevel)); } // Build mIDSelectors if (negation == aSelectorInTopLevel) { for (nsAtomList* curID = negation->mIDList; curID; curID = curID->mNext) { auto entry = static_cast<AtomSelectorEntry*> (aCascade->mIdSelectors.Add(curID->mAtom, fallible)); if (entry) { entry->mSelectors.AppendElement(SelectorPair(aSelectorInTopLevel, aRightmostSelector)); } } } else if (negation->mIDList) { aCascade->mPossiblyNegatedIDSelectors.AppendElement(aSelectorInTopLevel); } // Build mClassSelectors if (negation == aSelectorInTopLevel) { for (nsAtomList* curClass = negation->mClassList; curClass; curClass = curClass->mNext) { auto entry = static_cast<AtomSelectorEntry*> (aCascade->mClassSelectors.Add(curClass->mAtom, fallible)); if (entry) { entry->mSelectors.AppendElement(SelectorPair(aSelectorInTopLevel, aRightmostSelector)); } } } else if (negation->mClassList) { aCascade->mPossiblyNegatedClassSelectors.AppendElement(aSelectorInTopLevel); } // Build mAttributeSelectors. for (nsAttrSelector *attr = negation->mAttrList; attr; attr = attr->mNext) { nsTArray<SelectorPair> *array = aCascade->AttributeListFor(attr->mCasedAttr); if (!array) { return false; } array->AppendElement(SelectorPair(aSelectorInTopLevel, aRightmostSelector)); if (attr->mLowercaseAttr != attr->mCasedAttr) { array = aCascade->AttributeListFor(attr->mLowercaseAttr); if (!array) { return false; } array->AppendElement(SelectorPair(aSelectorInTopLevel, aRightmostSelector)); } } // Recur through any :-moz-any selectors for (nsPseudoClassList* pseudoClass = negation->mPseudoClassList; pseudoClass; pseudoClass = pseudoClass->mNext) { if (pseudoClass->mType == CSSPseudoClassType::any) { for (nsCSSSelectorList *l = pseudoClass->u.mSelectors; l; l = l->mNext) { nsCSSSelector *s = l->mSelectors; if (!AddSelector(aCascade, aSelectorInTopLevel, s, aRightmostSelector)) { return false; } } } } } return true; } static bool AddRule(RuleSelectorPair* aRuleInfo, RuleCascadeData* aCascade) { RuleCascadeData * const cascade = aCascade; // Build the rule hash. CSSPseudoElementType pseudoType = aRuleInfo->mSelector->PseudoType(); if (MOZ_LIKELY(pseudoType == CSSPseudoElementType::NotPseudo)) { cascade->mRuleHash.AppendRule(*aRuleInfo); } else if (pseudoType < CSSPseudoElementType::Count) { RuleHash*& ruleHash = cascade->mPseudoElementRuleHashes[ static_cast<CSSPseudoElementTypeBase>(pseudoType)]; if (!ruleHash) { ruleHash = new RuleHash(cascade->mQuirksMode); if (!ruleHash) { // Out of memory; give up return false; } } NS_ASSERTION(aRuleInfo->mSelector->mNext, "Must have mNext; parser screwed up"); NS_ASSERTION(aRuleInfo->mSelector->mNext->mOperator == ':', "Unexpected mNext combinator"); ruleHash->AppendRule(*aRuleInfo); } else if (pseudoType == CSSPseudoElementType::AnonBox) { NS_ASSERTION(!aRuleInfo->mSelector->mCasedTag && !aRuleInfo->mSelector->mIDList && !aRuleInfo->mSelector->mClassList && !aRuleInfo->mSelector->mPseudoClassList && !aRuleInfo->mSelector->mAttrList && !aRuleInfo->mSelector->mNegations && !aRuleInfo->mSelector->mNext && aRuleInfo->mSelector->mNameSpace == kNameSpaceID_Unknown, "Parser messed up with anon box selector"); // Index doesn't matter here, since we'll just be walking these // rules in order; just pass 0. AppendRuleToTagTable(&cascade->mAnonBoxRules, aRuleInfo->mSelector->mLowercaseTag, RuleValue(*aRuleInfo, 0, aCascade->mQuirksMode)); } else { #ifdef MOZ_XUL NS_ASSERTION(pseudoType == CSSPseudoElementType::XULTree, "Unexpected pseudo type"); // Index doesn't matter here, since we'll just be walking these // rules in order; just pass 0. AppendRuleToTagTable(&cascade->mXULTreeRules, aRuleInfo->mSelector->mLowercaseTag, RuleValue(*aRuleInfo, 0, aCascade->mQuirksMode)); #else NS_NOTREACHED("Unexpected pseudo type"); #endif } for (nsCSSSelector* selector = aRuleInfo->mSelector; selector; selector = selector->mNext) { if (selector->IsPseudoElement()) { CSSPseudoElementType pseudo = selector->PseudoType(); if (pseudo >= CSSPseudoElementType::Count || !nsCSSPseudoElements::PseudoElementSupportsUserActionState(pseudo)) { NS_ASSERTION(!selector->mNegations, "Shouldn't have negations"); // We do store selectors ending with pseudo-elements that allow :hover // and :active after them in the hashtables corresponding to that // selector's mNext (i.e. the thing that matches against the element), // but we want to make sure that selectors for any other kinds of // pseudo-elements don't end up in the hashtables. In particular, tree // pseudos store strange things in mPseudoClassList that we don't want // to try to match elements against. continue; } } if (!AddSelector(cascade, selector, selector, aRuleInfo->mSelector)) { return false; } } return true; } struct PerWeightDataListItem : public RuleSelectorPair { PerWeightDataListItem(css::StyleRule* aRule, nsCSSSelector* aSelector) : RuleSelectorPair(aRule, aSelector) , mNext(nullptr) {} // No destructor; these are arena-allocated // Placement new to arena allocate the PerWeightDataListItem void *operator new(size_t aSize, PLArenaPool &aArena) CPP_THROW_NEW { void *mem; PL_ARENA_ALLOCATE(mem, &aArena, aSize); return mem; } PerWeightDataListItem *mNext; }; struct PerWeightData { PerWeightData() : mRuleSelectorPairs(nullptr) , mTail(&mRuleSelectorPairs) {} int32_t mWeight; PerWeightDataListItem *mRuleSelectorPairs; PerWeightDataListItem **mTail; }; struct RuleByWeightEntry : public PLDHashEntryHdr { PerWeightData data; // mWeight is key, mRuleSelectorPairs are value }; static PLDHashNumber HashIntKey(const void *key) { return PLDHashNumber(NS_PTR_TO_INT32(key)); } static bool MatchWeightEntry(const PLDHashEntryHdr *hdr, const void *key) { const RuleByWeightEntry *entry = (const RuleByWeightEntry *)hdr; return entry->data.mWeight == NS_PTR_TO_INT32(key); } static void InitWeightEntry(PLDHashEntryHdr *hdr, const void *key) { RuleByWeightEntry* entry = static_cast<RuleByWeightEntry*>(hdr); new (KnownNotNull, entry) RuleByWeightEntry(); } static const PLDHashTableOps gRulesByWeightOps = { HashIntKey, MatchWeightEntry, PLDHashTable::MoveEntryStub, PLDHashTable::ClearEntryStub, InitWeightEntry }; struct CascadeEnumData { CascadeEnumData(nsPresContext* aPresContext, nsTArray<nsFontFaceRuleContainer>& aFontFaceRules, nsTArray<nsCSSKeyframesRule*>& aKeyframesRules, nsTArray<nsCSSFontFeatureValuesRule*>& aFontFeatureValuesRules, nsTArray<nsCSSPageRule*>& aPageRules, nsTArray<nsCSSCounterStyleRule*>& aCounterStyleRules, nsTArray<css::DocumentRule*>& aDocumentRules, nsMediaQueryResultCacheKey& aKey, nsDocumentRuleResultCacheKey& aDocumentKey, SheetType aSheetType, bool aMustGatherDocumentRules) : mPresContext(aPresContext), mFontFaceRules(aFontFaceRules), mKeyframesRules(aKeyframesRules), mFontFeatureValuesRules(aFontFeatureValuesRules), mPageRules(aPageRules), mCounterStyleRules(aCounterStyleRules), mDocumentRules(aDocumentRules), mCacheKey(aKey), mDocumentCacheKey(aDocumentKey), mRulesByWeight(&gRulesByWeightOps, sizeof(RuleByWeightEntry), 32), mSheetType(aSheetType), mMustGatherDocumentRules(aMustGatherDocumentRules) { // Initialize our arena PL_INIT_ARENA_POOL(&mArena, "CascadeEnumDataArena", NS_CASCADEENUMDATA_ARENA_BLOCK_SIZE); } ~CascadeEnumData() { PL_FinishArenaPool(&mArena); } nsPresContext* mPresContext; nsTArray<nsFontFaceRuleContainer>& mFontFaceRules; nsTArray<nsCSSKeyframesRule*>& mKeyframesRules; nsTArray<nsCSSFontFeatureValuesRule*>& mFontFeatureValuesRules; nsTArray<nsCSSPageRule*>& mPageRules; nsTArray<nsCSSCounterStyleRule*>& mCounterStyleRules; nsTArray<css::DocumentRule*>& mDocumentRules; nsMediaQueryResultCacheKey& mCacheKey; nsDocumentRuleResultCacheKey& mDocumentCacheKey; PLArenaPool mArena; // Hooray, a manual PLDHashTable since nsClassHashtable doesn't // provide a getter that gives me a *reference* to the value. PLDHashTable mRulesByWeight; // of PerWeightDataListItem linked lists SheetType mSheetType; bool mMustGatherDocumentRules; }; /** * Recursively traverses rules in order to: * (1) add any @-moz-document rules into data->mDocumentRules. * (2) record any @-moz-document rules whose conditions evaluate to true * on data->mDocumentCacheKey. * * See also CascadeRuleEnumFunc below, which calls us via * EnumerateRulesForwards. If modifying this function you may need to * update CascadeRuleEnumFunc too. */ static bool GatherDocRuleEnumFunc(css::Rule* aRule, void* aData) { CascadeEnumData* data = (CascadeEnumData*)aData; int32_t type = aRule->GetType(); MOZ_ASSERT(data->mMustGatherDocumentRules, "should only call GatherDocRuleEnumFunc if " "mMustGatherDocumentRules is true"); if (css::Rule::MEDIA_RULE == type || css::Rule::SUPPORTS_RULE == type) { css::GroupRule* groupRule = static_cast<css::GroupRule*>(aRule); if (!groupRule->EnumerateRulesForwards(GatherDocRuleEnumFunc, aData)) { return false; } } else if (css::Rule::DOCUMENT_RULE == type) { css::DocumentRule* docRule = static_cast<css::DocumentRule*>(aRule); if (!data->mDocumentRules.AppendElement(docRule)) { return false; } if (docRule->UseForPresentation(data->mPresContext)) { if (!data->mDocumentCacheKey.AddMatchingRule(docRule)) { return false; } } if (!docRule->EnumerateRulesForwards(GatherDocRuleEnumFunc, aData)) { return false; } } return true; } /* * This enumerates style rules in a sheet (and recursively into any * grouping rules) in order to: * (1) add any style rules, in order, into data->mRulesByWeight (for * the primary CSS cascade), where they are separated by weight * but kept in order per-weight, and * (2) add any @font-face rules, in order, into data->mFontFaceRules. * (3) add any @keyframes rules, in order, into data->mKeyframesRules. * (4) add any @font-feature-value rules, in order, * into data->mFontFeatureValuesRules. * (5) add any @page rules, in order, into data->mPageRules. * (6) add any @counter-style rules, in order, into data->mCounterStyleRules. * (7) add any @-moz-document rules into data->mDocumentRules. * (8) record any @-moz-document rules whose conditions evaluate to true * on data->mDocumentCacheKey. * * See also GatherDocRuleEnumFunc above, which we call to traverse into * @-moz-document rules even if their (or an ancestor's) condition * fails. This means we might look at the result of some @-moz-document * rules that don't actually affect whether a RuleProcessorCache lookup * is a hit or a miss. The presence of @-moz-document rules inside * @media etc. rules should be rare, and looking at all of them in the * sheets lets us avoid the complication of having different document * cache key results for different media. * * If modifying this function you may need to update * GatherDocRuleEnumFunc too. */ static bool CascadeRuleEnumFunc(css::Rule* aRule, void* aData) { CascadeEnumData* data = (CascadeEnumData*)aData; int32_t type = aRule->GetType(); if (css::Rule::STYLE_RULE == type) { css::StyleRule* styleRule = static_cast<css::StyleRule*>(aRule); for (nsCSSSelectorList *sel = styleRule->Selector(); sel; sel = sel->mNext) { int32_t weight = sel->mWeight; auto entry = static_cast<RuleByWeightEntry*> (data->mRulesByWeight.Add(NS_INT32_TO_PTR(weight), fallible)); if (!entry) return false; entry->data.mWeight = weight; // entry->data.mRuleSelectorPairs should be linked in forward order; // entry->data.mTail is the slot to write to. auto* newItem = new (data->mArena) PerWeightDataListItem(styleRule, sel->mSelectors); if (newItem) { *(entry->data.mTail) = newItem; entry->data.mTail = &newItem->mNext; } } } else if (css::Rule::MEDIA_RULE == type || css::Rule::SUPPORTS_RULE == type) { css::GroupRule* groupRule = static_cast<css::GroupRule*>(aRule); const bool use = groupRule->UseForPresentation(data->mPresContext, data->mCacheKey); if (use || data->mMustGatherDocumentRules) { if (!groupRule->EnumerateRulesForwards(use ? CascadeRuleEnumFunc : GatherDocRuleEnumFunc, aData)) { return false; } } } else if (css::Rule::DOCUMENT_RULE == type) { css::DocumentRule* docRule = static_cast<css::DocumentRule*>(aRule); if (data->mMustGatherDocumentRules) { if (!data->mDocumentRules.AppendElement(docRule)) { return false; } } const bool use = docRule->UseForPresentation(data->mPresContext); if (use && data->mMustGatherDocumentRules) { if (!data->mDocumentCacheKey.AddMatchingRule(docRule)) { return false; } } if (use || data->mMustGatherDocumentRules) { if (!docRule->EnumerateRulesForwards(use ? CascadeRuleEnumFunc : GatherDocRuleEnumFunc, aData)) { return false; } } } else if (css::Rule::FONT_FACE_RULE == type) { nsCSSFontFaceRule *fontFaceRule = static_cast<nsCSSFontFaceRule*>(aRule); nsFontFaceRuleContainer *ptr = data->mFontFaceRules.AppendElement(); if (!ptr) return false; ptr->mRule = fontFaceRule; ptr->mSheetType = data->mSheetType; } else if (css::Rule::KEYFRAMES_RULE == type) { nsCSSKeyframesRule *keyframesRule = static_cast<nsCSSKeyframesRule*>(aRule); if (!data->mKeyframesRules.AppendElement(keyframesRule)) { return false; } } else if (css::Rule::FONT_FEATURE_VALUES_RULE == type) { nsCSSFontFeatureValuesRule *fontFeatureValuesRule = static_cast<nsCSSFontFeatureValuesRule*>(aRule); if (!data->mFontFeatureValuesRules.AppendElement(fontFeatureValuesRule)) { return false; } } else if (css::Rule::PAGE_RULE == type) { nsCSSPageRule* pageRule = static_cast<nsCSSPageRule*>(aRule); if (!data->mPageRules.AppendElement(pageRule)) { return false; } } else if (css::Rule::COUNTER_STYLE_RULE == type) { nsCSSCounterStyleRule* counterStyleRule = static_cast<nsCSSCounterStyleRule*>(aRule); if (!data->mCounterStyleRules.AppendElement(counterStyleRule)) { return false; } } return true; } /* static */ bool nsCSSRuleProcessor::CascadeSheet(CSSStyleSheet* aSheet, CascadeEnumData* aData) { if (aSheet->IsApplicable() && aSheet->UseForPresentation(aData->mPresContext, aData->mCacheKey) && aSheet->mInner) { CSSStyleSheet* child = aSheet->mInner->mFirstChild; while (child) { CascadeSheet(child, aData); child = child->mNext; } if (!aSheet->mInner->mOrderedRules.EnumerateForwards(CascadeRuleEnumFunc, aData)) return false; } return true; } static int CompareWeightData(const void* aArg1, const void* aArg2, void* closure) { const PerWeightData* arg1 = static_cast<const PerWeightData*>(aArg1); const PerWeightData* arg2 = static_cast<const PerWeightData*>(aArg2); return arg1->mWeight - arg2->mWeight; // put lower weight first } RuleCascadeData* nsCSSRuleProcessor::GetRuleCascade(nsPresContext* aPresContext) { // FIXME: Make this infallible! // If anything changes about the presentation context, we will be // notified. Otherwise, our cache is valid if mLastPresContext // matches aPresContext. (The only rule processors used for multiple // pres contexts are for XBL. These rule processors are probably less // likely to have @media rules, and thus the cache is pretty likely to // hit instantly even when we're switching between pres contexts.) if (!mRuleCascades || aPresContext != mLastPresContext) { RefreshRuleCascade(aPresContext); } mLastPresContext = aPresContext; return mRuleCascades; } void nsCSSRuleProcessor::RefreshRuleCascade(nsPresContext* aPresContext) { // Having RuleCascadeData objects be per-medium (over all variation // caused by media queries, handled through mCacheKey) works for now // since nsCSSRuleProcessor objects are per-document. (For a given // set of stylesheets they can vary based on medium (@media) or // document (@-moz-document).) for (RuleCascadeData **cascadep = &mRuleCascades, *cascade; (cascade = *cascadep); cascadep = &cascade->mNext) { if (cascade->mCacheKey.Matches(aPresContext)) { // Ensure that the current one is always mRuleCascades. *cascadep = cascade->mNext; cascade->mNext = mRuleCascades; mRuleCascades = cascade; return; } } // We're going to make a new rule cascade; this means that we should // now stop using the previous cache key that we're holding on to from // the last time we had rule cascades. mPreviousCacheKey = nullptr; if (mSheets.Length() != 0) { nsAutoPtr<RuleCascadeData> newCascade( new RuleCascadeData(aPresContext->Medium(), eCompatibility_NavQuirks == aPresContext->CompatibilityMode())); if (newCascade) { CascadeEnumData data(aPresContext, newCascade->mFontFaceRules, newCascade->mKeyframesRules, newCascade->mFontFeatureValuesRules, newCascade->mPageRules, newCascade->mCounterStyleRules, mDocumentRules, newCascade->mCacheKey, mDocumentCacheKey, mSheetType, mMustGatherDocumentRules); for (uint32_t i = 0; i < mSheets.Length(); ++i) { if (!CascadeSheet(mSheets.ElementAt(i), &data)) return; /* out of memory */ } // Sort the hash table of per-weight linked lists by weight. uint32_t weightCount = data.mRulesByWeight.EntryCount(); auto weightArray = MakeUnique<PerWeightData[]>(weightCount); int32_t j = 0; for (auto iter = data.mRulesByWeight.Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast<const RuleByWeightEntry*>(iter.Get()); weightArray[j++] = entry->data; } NS_QuickSort(weightArray.get(), weightCount, sizeof(PerWeightData), CompareWeightData, nullptr); // Put things into the rule hash. // The primary sort is by weight... for (uint32_t i = 0; i < weightCount; ++i) { // and the secondary sort is by order. mRuleSelectorPairs is already in // the right order.. for (PerWeightDataListItem *cur = weightArray[i].mRuleSelectorPairs; cur; cur = cur->mNext) { if (!AddRule(cur, newCascade)) return; /* out of memory */ } } // Build mKeyframesRuleTable. for (nsTArray<nsCSSKeyframesRule*>::size_type i = 0, iEnd = newCascade->mKeyframesRules.Length(); i < iEnd; ++i) { nsCSSKeyframesRule* rule = newCascade->mKeyframesRules[i]; newCascade->mKeyframesRuleTable.Put(rule->GetName(), rule); } // Build mCounterStyleRuleTable for (nsTArray<nsCSSCounterStyleRule*>::size_type i = 0, iEnd = newCascade->mCounterStyleRules.Length(); i < iEnd; ++i) { nsCSSCounterStyleRule* rule = newCascade->mCounterStyleRules[i]; newCascade->mCounterStyleRuleTable.Put(rule->GetName(), rule); } // mMustGatherDocumentRules controls whether we build mDocumentRules // and mDocumentCacheKey so that they can be used as keys by the // RuleProcessorCache, as obtained by TakeDocumentRulesAndCacheKey // later. We set it to false just below so that we only do this // the first time we build a RuleProcessorCache for a shared rule // processor. // // An up-to-date mDocumentCacheKey is only needed if we // are still in the RuleProcessorCache (as we store a copy of the // cache key in the RuleProcessorCache), and an up-to-date // mDocumentRules is only needed at the time TakeDocumentRulesAndCacheKey // is called, which is immediately after the rule processor is created // (by nsStyleSet). // // Note that when nsCSSRuleProcessor::ClearRuleCascades is called, // by CSSStyleSheet::ClearRuleCascades, we will have called // RuleProcessorCache::RemoveSheet, which will remove the rule // processor from the cache. (This is because the list of document // rules now may not match the one used as they key in the // RuleProcessorCache.) // // Thus, as we'll no longer be in the RuleProcessorCache, and we won't // have TakeDocumentRulesAndCacheKey called on us, we don't need to ensure // mDocumentCacheKey and mDocumentRules are up-to-date after the // first time GetRuleCascade is called. if (mMustGatherDocumentRules) { mDocumentRules.Sort(); mDocumentCacheKey.Finalize(); mMustGatherDocumentRules = false; #ifdef DEBUG mDocumentRulesAndCacheKeyValid = true; #endif } // Ensure that the current one is always mRuleCascades. newCascade->mNext = mRuleCascades; mRuleCascades = newCascade.forget(); } } return; } /* static */ bool nsCSSRuleProcessor::SelectorListMatches(Element* aElement, TreeMatchContext& aTreeMatchContext, nsCSSSelectorList* aSelectorList) { MOZ_ASSERT(!aTreeMatchContext.mForScopedStyle, "mCurrentStyleScope will need to be saved and restored after the " "SelectorMatchesTree call"); while (aSelectorList) { nsCSSSelector* sel = aSelectorList->mSelectors; NS_ASSERTION(sel, "Should have *some* selectors"); NS_ASSERTION(!sel->IsPseudoElement(), "Shouldn't have been called"); NodeMatchContext nodeContext(EventStates(), false); if (SelectorMatches(aElement, sel, nodeContext, aTreeMatchContext, SelectorMatchesFlags::NONE)) { nsCSSSelector* next = sel->mNext; if (!next || SelectorMatchesTree(aElement, next, aTreeMatchContext, SelectorMatchesTreeFlags(0))) { return true; } } aSelectorList = aSelectorList->mNext; } return false; } void nsCSSRuleProcessor::TakeDocumentRulesAndCacheKey( nsPresContext* aPresContext, nsTArray<css::DocumentRule*>& aDocumentRules, nsDocumentRuleResultCacheKey& aCacheKey) { MOZ_ASSERT(mIsShared); GetRuleCascade(aPresContext); MOZ_ASSERT(mDocumentRulesAndCacheKeyValid); aDocumentRules.Clear(); aDocumentRules.SwapElements(mDocumentRules); aCacheKey.Swap(mDocumentCacheKey); #ifdef DEBUG mDocumentRulesAndCacheKeyValid = false; #endif } void nsCSSRuleProcessor::AddStyleSetRef() { MOZ_ASSERT(mIsShared); if (++mStyleSetRefCnt == 1) { RuleProcessorCache::StopTracking(this); } } void nsCSSRuleProcessor::ReleaseStyleSetRef() { MOZ_ASSERT(mIsShared); MOZ_ASSERT(mStyleSetRefCnt > 0); if (--mStyleSetRefCnt == 0 && mInRuleProcessorCache) { RuleProcessorCache::StartTracking(this); } } // TreeMatchContext and AncestorFilter out of line methods void TreeMatchContext::InitAncestors(Element *aElement) { MOZ_ASSERT(!mAncestorFilter.mFilter); MOZ_ASSERT(mAncestorFilter.mHashes.IsEmpty()); MOZ_ASSERT(mStyleScopes.IsEmpty()); mAncestorFilter.mFilter = new AncestorFilter::Filter(); if (MOZ_LIKELY(aElement)) { MOZ_ASSERT(aElement->GetUncomposedDoc() || aElement->HasFlag(NODE_IS_IN_SHADOW_TREE), "aElement must be in the document or in shadow tree " "for the assumption that GetParentNode() is non-null " "on all element ancestors of aElement to be true"); // Collect up the ancestors AutoTArray<Element*, 50> ancestors; Element* cur = aElement; do { ancestors.AppendElement(cur); cur = cur->GetParentElementCrossingShadowRoot(); } while (cur); // Now push them in reverse order. for (uint32_t i = ancestors.Length(); i-- != 0; ) { mAncestorFilter.PushAncestor(ancestors[i]); PushStyleScope(ancestors[i]); } } } void TreeMatchContext::InitStyleScopes(Element* aElement) { MOZ_ASSERT(mStyleScopes.IsEmpty()); if (MOZ_LIKELY(aElement)) { // Collect up the ancestors AutoTArray<Element*, 50> ancestors; Element* cur = aElement; do { ancestors.AppendElement(cur); cur = cur->GetParentElementCrossingShadowRoot(); } while (cur); // Now push them in reverse order. for (uint32_t i = ancestors.Length(); i-- != 0; ) { PushStyleScope(ancestors[i]); } } } void AncestorFilter::PushAncestor(Element *aElement) { MOZ_ASSERT(mFilter); uint32_t oldLength = mHashes.Length(); mPopTargets.AppendElement(oldLength); #ifdef DEBUG mElements.AppendElement(aElement); #endif mHashes.AppendElement(aElement->NodeInfo()->NameAtom()->hash()); nsIAtom *id = aElement->GetID(); if (id) { mHashes.AppendElement(id->hash()); } const nsAttrValue *classes = aElement->GetClasses(); if (classes) { uint32_t classCount = classes->GetAtomCount(); for (uint32_t i = 0; i < classCount; ++i) { mHashes.AppendElement(classes->AtomAt(i)->hash()); } } uint32_t newLength = mHashes.Length(); for (uint32_t i = oldLength; i < newLength; ++i) { mFilter->add(mHashes[i]); } } void AncestorFilter::PopAncestor() { MOZ_ASSERT(!mPopTargets.IsEmpty()); MOZ_ASSERT(mPopTargets.Length() == mElements.Length()); uint32_t popTargetLength = mPopTargets.Length(); uint32_t newLength = mPopTargets[popTargetLength-1]; mPopTargets.TruncateLength(popTargetLength-1); #ifdef DEBUG mElements.TruncateLength(popTargetLength-1); #endif uint32_t oldLength = mHashes.Length(); for (uint32_t i = newLength; i < oldLength; ++i) { mFilter->remove(mHashes[i]); } mHashes.TruncateLength(newLength); } #ifdef DEBUG void AncestorFilter::AssertHasAllAncestors(Element *aElement) const { Element* cur = aElement->GetParentElementCrossingShadowRoot(); while (cur) { MOZ_ASSERT(mElements.Contains(cur)); cur = cur->GetParentElementCrossingShadowRoot(); } } void TreeMatchContext::AssertHasAllStyleScopes(Element* aElement) const { if (aElement->IsInNativeAnonymousSubtree()) { // Document style sheets are never applied to native anonymous content, // so it's not possible for them to be in a <style scoped> scope. return; } Element* cur = aElement->GetParentElementCrossingShadowRoot(); while (cur) { if (cur->IsScopedStyleRoot()) { MOZ_ASSERT(mStyleScopes.Contains(cur)); } cur = cur->GetParentElementCrossingShadowRoot(); } } #endif