diff -r 000000000000 -r 6474c204b198 layout/style/nsRuleNode.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/layout/style/nsRuleNode.h Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,807 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * a node in the lexicographic tree of rules that match an element, + * responsible for converting the rules' information into computed style + */ + +#ifndef nsRuleNode_h___ +#define nsRuleNode_h___ + +#include "nsPresContext.h" +#include "nsStyleStruct.h" + +#include + +class nsStyleContext; +struct nsRuleData; +class nsIStyleRule; +struct nsCSSValueList; + +class nsCSSValue; +struct nsCSSRect; + +class nsStyleCoord; +struct nsCSSValuePairList; + +template +class FixedStyleStructArray +{ +private: + void* mArray[Count]; +public: + void*& operator[](nsStyleStructID aIndex) { + NS_ABORT_IF_FALSE(MinIndex <= aIndex && aIndex < (MinIndex + Count), + "out of range"); + return mArray[aIndex - MinIndex]; + } + + const void* operator[](nsStyleStructID aIndex) const { + NS_ABORT_IF_FALSE(MinIndex <= aIndex && aIndex < (MinIndex + Count), + "out of range"); + return mArray[aIndex - MinIndex]; + } +}; + +struct nsInheritedStyleData +{ + FixedStyleStructArray mStyleStructs; + + void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW { + return aContext->AllocateFromShell(sz); + } + + void DestroyStructs(uint64_t aBits, nsPresContext* aContext) { +#define STYLE_STRUCT_INHERITED(name, checkdata_cb) \ + void *name##Data = mStyleStructs[eStyleStruct_##name]; \ + if (name##Data && !(aBits & NS_STYLE_INHERIT_BIT(name))) \ + static_cast(name##Data)->Destroy(aContext); +#define STYLE_STRUCT_RESET(name, checkdata_cb) + +#include "nsStyleStructList.h" + +#undef STYLE_STRUCT_INHERITED +#undef STYLE_STRUCT_RESET + } + + void Destroy(uint64_t aBits, nsPresContext* aContext) { + DestroyStructs(aBits, aContext); + aContext->FreeToShell(sizeof(nsInheritedStyleData), this); + } + + nsInheritedStyleData() { + for (nsStyleStructID i = nsStyleStructID_Inherited_Start; + i < nsStyleStructID_Inherited_Start + nsStyleStructID_Inherited_Count; + i = nsStyleStructID(i + 1)) { + mStyleStructs[i] = nullptr; + } + } +}; + +struct nsResetStyleData +{ + FixedStyleStructArray mStyleStructs; + + nsResetStyleData() + { + for (nsStyleStructID i = nsStyleStructID_Reset_Start; + i < nsStyleStructID_Reset_Start + nsStyleStructID_Reset_Count; + i = nsStyleStructID(i + 1)) { + mStyleStructs[i] = nullptr; + } + } + + void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW { + return aContext->AllocateFromShell(sz); + } + + void Destroy(uint64_t aBits, nsPresContext* aContext) { +#define STYLE_STRUCT_RESET(name, checkdata_cb) \ + void *name##Data = mStyleStructs[eStyleStruct_##name]; \ + if (name##Data && !(aBits & NS_STYLE_INHERIT_BIT(name))) \ + static_cast(name##Data)->Destroy(aContext); +#define STYLE_STRUCT_INHERITED(name, checkdata_cb) + +#include "nsStyleStructList.h" + +#undef STYLE_STRUCT_RESET +#undef STYLE_STRUCT_INHERITED + + aContext->FreeToShell(sizeof(nsResetStyleData), this); + } +}; + +struct nsCachedStyleData +{ + nsInheritedStyleData* mInheritedData; + nsResetStyleData* mResetData; + + static bool IsReset(const nsStyleStructID aSID) { + NS_ABORT_IF_FALSE(0 <= aSID && aSID < nsStyleStructID_Length, + "must be an inherited or reset SID"); + return nsStyleStructID_Reset_Start <= aSID; + } + + static bool IsInherited(const nsStyleStructID aSID) { + return !IsReset(aSID); + } + + static uint32_t GetBitForSID(const nsStyleStructID aSID) { + return 1 << aSID; + } + + void* NS_FASTCALL GetStyleData(const nsStyleStructID aSID) { + if (IsReset(aSID)) { + if (mResetData) { + return mResetData->mStyleStructs[aSID]; + } + } else { + if (mInheritedData) { + return mInheritedData->mStyleStructs[aSID]; + } + } + return nullptr; + } + + void NS_FASTCALL SetStyleData(const nsStyleStructID aSID, + nsPresContext *aPresContext, void *aData) { + if (IsReset(aSID)) { + if (!mResetData) { + mResetData = new (aPresContext) nsResetStyleData; + } + mResetData->mStyleStructs[aSID] = aData; + } else { + if (!mInheritedData) { + mInheritedData = new (aPresContext) nsInheritedStyleData; + } + mInheritedData->mStyleStructs[aSID] = aData; + } + } + + // Typesafe and faster versions of the above + #define STYLE_STRUCT_INHERITED(name_, checkdata_cb_) \ + nsStyle##name_ * NS_FASTCALL GetStyle##name_ () { \ + return mInheritedData ? static_cast( \ + mInheritedData->mStyleStructs[eStyleStruct_##name_]) : nullptr; \ + } + #define STYLE_STRUCT_RESET(name_, checkdata_cb_) \ + nsStyle##name_ * NS_FASTCALL GetStyle##name_ () { \ + return mResetData ? static_cast( \ + mResetData->mStyleStructs[eStyleStruct_##name_]) : nullptr; \ + } + #include "nsStyleStructList.h" + #undef STYLE_STRUCT_RESET + #undef STYLE_STRUCT_INHERITED + + void Destroy(uint64_t aBits, nsPresContext* aContext) { + if (mResetData) + mResetData->Destroy(aBits, aContext); + if (mInheritedData) + mInheritedData->Destroy(aBits, aContext); + mResetData = nullptr; + mInheritedData = nullptr; + } + + nsCachedStyleData() :mInheritedData(nullptr), mResetData(nullptr) {} + ~nsCachedStyleData() {} +}; + +/** + * nsRuleNode is a node in a lexicographic tree (the "rule tree") + * indexed by style rules (implementations of nsIStyleRule). + * + * The rule tree is owned by the nsStyleSet and is destroyed when the + * presentation of the document goes away. It is garbage-collected + * (using mark-and-sweep garbage collection) during the lifetime of the + * document (when dynamic changes cause the destruction of enough style + * contexts). Rule nodes are marked if they are pointed to by a style + * context or one of their descendants is. + * + * An nsStyleContext, which represents the computed style data for an + * element, points to an nsRuleNode. The path from the root of the rule + * tree to the nsStyleContext's mRuleNode gives the list of the rules + * matched, from least important in the cascading order to most + * important in the cascading order. + * + * The reason for using a lexicographic tree is that it allows for + * sharing of style data, which saves both memory (for storing the + * computed style data) and time (for computing them). This sharing + * depends on the computed style data being stored in structs (nsStyle*) + * that contain only properties that are inherited by default + * ("inherited structs") or structs that contain only properties that + * are not inherited by default ("reset structs"). The optimization + * depends on the normal case being that style rules specify relatively + * few properties and even that elements generally have relatively few + * properties specified. This allows sharing in the following ways: + * 1. [mainly reset structs] When a style data struct will contain the + * same computed value for any elements that match the same set of + * rules (common for reset structs), it can be stored on the + * nsRuleNode instead of on the nsStyleContext. + * 2. [only? reset structs] When (1) occurs, and an nsRuleNode doesn't + * have any rules that change the values in the struct, the + * nsRuleNode can share that struct with its parent nsRuleNode. + * 3. [mainly inherited structs] When an element doesn't match any + * rules that change the value of a property (or, in the edge case, + * when all the values specified are 'inherit'), the nsStyleContext + * can use the same nsStyle* struct as its parent nsStyleContext. + * + * Since the data represented by an nsIStyleRule are immutable, the data + * represented by an nsRuleNode are also immutable. + */ + +enum nsFontSizeType { + eFontSize_HTML = 1, + eFontSize_CSS = 2 +}; + +class nsRuleNode { +public: + enum RuleDetail { + eRuleNone, // No props have been specified at all. + eRulePartialReset, // At least one prop with a non-"inherit" value + // has been specified. No props have been + // specified with an "inherit" value. At least + // one prop remains unspecified. + eRulePartialMixed, // At least one prop with a non-"inherit" value + // has been specified. Some props may also have + // been specified with an "inherit" value. At + // least one prop remains unspecified. + eRulePartialInherited, // Only props with "inherit" values have + // have been specified. At least one prop + // remains unspecified. + eRuleFullReset, // All props have been specified. None has an + // "inherit" value. + eRuleFullMixed, // All props have been specified. At least one has + // a non-"inherit" value. + eRuleFullInherited // All props have been specified with "inherit" + // values. + }; + +private: + nsPresContext* const mPresContext; // Our pres context. + + nsRuleNode* const mParent; // A pointer to the parent node in the tree. + // This enables us to walk backwards from the + // most specific rule matched to the least + // specific rule (which is the optimal order to + // use for lookups of style properties. + nsIStyleRule* const mRule; // [STRONG] A pointer to our specific rule. + + nsRuleNode* mNextSibling; // This value should be used only by the + // parent, since the parent may store + // children in a hash, which means this + // pointer is not meaningful. Order of + // siblings is also not meaningful. + + struct Key { + nsIStyleRule* mRule; + uint8_t mLevel; + bool mIsImportantRule; + + Key(nsIStyleRule* aRule, uint8_t aLevel, bool aIsImportantRule) + : mRule(aRule), mLevel(aLevel), mIsImportantRule(aIsImportantRule) + {} + + bool operator==(const Key& aOther) const + { + return mRule == aOther.mRule && + mLevel == aOther.mLevel && + mIsImportantRule == aOther.mIsImportantRule; + } + + bool operator!=(const Key& aOther) const + { + return !(*this == aOther); + } + }; + + static PLDHashNumber + ChildrenHashHashKey(PLDHashTable *aTable, const void *aKey); + + static bool + ChildrenHashMatchEntry(PLDHashTable *aTable, + const PLDHashEntryHdr *aHdr, + const void *aKey); + + static const PLDHashTableOps ChildrenHashOps; + + static PLDHashOperator + EnqueueRuleNodeChildren(PLDHashTable *table, PLDHashEntryHdr *hdr, + uint32_t number, void *arg); + + Key GetKey() const { + return Key(mRule, GetLevel(), IsImportantRule()); + } + + // The children of this node are stored in either a hashtable or list + // that maps from rules to our nsRuleNode children. When matching + // rules, we use this mapping to transition from node to node + // (constructing new nodes as needed to flesh out the tree). + + union { + void* asVoid; + nsRuleNode* asList; + PLDHashTable* asHash; + } mChildren; // Accessed only through the methods below. + + enum { + kTypeMask = 0x1, + kListType = 0x0, + kHashType = 0x1 + }; + enum { + // Maximum to have in a list before converting to a hashtable. + // XXX Need to optimize this. + kMaxChildrenInList = 32 + }; + + bool HaveChildren() const { + return mChildren.asVoid != nullptr; + } + bool ChildrenAreHashed() { + return (intptr_t(mChildren.asVoid) & kTypeMask) == kHashType; + } + nsRuleNode* ChildrenList() { + return mChildren.asList; + } + nsRuleNode** ChildrenListPtr() { + return &mChildren.asList; + } + PLDHashTable* ChildrenHash() { + return (PLDHashTable*) (intptr_t(mChildren.asHash) & ~intptr_t(kTypeMask)); + } + void SetChildrenList(nsRuleNode *aList) { + NS_ASSERTION(!(intptr_t(aList) & kTypeMask), + "pointer not 2-byte aligned"); + mChildren.asList = aList; + } + void SetChildrenHash(PLDHashTable *aHashtable) { + NS_ASSERTION(!(intptr_t(aHashtable) & kTypeMask), + "pointer not 2-byte aligned"); + mChildren.asHash = (PLDHashTable*)(intptr_t(aHashtable) | kHashType); + } + void ConvertChildrenToHash(); + + nsCachedStyleData mStyleData; // Any data we cached on the rule node. + + uint32_t mDependentBits; // Used to cache the fact that we can look up + // cached data under a parent rule. + + uint32_t mNoneBits; // Used to cache the fact that the branch to this + // node specifies no non-inherited data for a + // given struct type. (This usually implies that + // the entire branch specifies no non-inherited + // data, although not necessarily, if a + // non-inherited value is overridden by an + // explicit 'inherit' value.) For example, if an + // entire rule branch specifies no color + // information, then a bit will be set along every + // rule node on that branch, so that you can break + // out of the rule tree early and just inherit + // from the parent style context. The presence of + // this bit means we should just get inherited + // data from the parent style context, and it is + // never used for reset structs since their + // Compute*Data functions don't initialize from + // inherited data. + + // Reference count. This just counts the style contexts that reference this + // rulenode. And children the rulenode has had. When this goes to 0 or + // stops being 0, we notify the style set. + // Note, in particular, that when a child is removed mRefCnt is NOT + // decremented. This is on purpose; the notifications to the style set are + // only used to determine when it's worth running GC on the ruletree, and + // this setup makes it so we only count unused ruletree leaves for purposes + // of deciding when to GC. We could more accurately count unused rulenodes + // by releasing/addrefing our parent when our refcount transitions to or from + // 0, but it doesn't seem worth it to do that. + uint32_t mRefCnt; + +public: + // Overloaded new operator. Initializes the memory to 0 and relies on an arena + // (which comes from the presShell) to perform the allocation. + void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW; + void Destroy() { DestroyInternal(nullptr); } + + // Implemented in nsStyleSet.h, since it needs to know about nsStyleSet. + inline void AddRef(); + + // Implemented in nsStyleSet.h, since it needs to know about nsStyleSet. + inline void Release(); + +protected: + void DestroyInternal(nsRuleNode ***aDestroyQueueTail); + void PropagateDependentBit(nsStyleStructID aSID, nsRuleNode* aHighestNode, + void* aStruct); + void PropagateNoneBit(uint32_t aBit, nsRuleNode* aHighestNode); + + const void* SetDefaultOnRoot(const nsStyleStructID aSID, + nsStyleContext* aContext); + + /** + * Resolves any property values in aRuleData for a given style struct that + * have eCSSUnit_TokenStream values, by resolving them against the computed + * variable values on the style context and re-parsing the property. + * + * @return Whether any properties with eCSSUnit_TokenStream values were + * encountered. + */ + static bool ResolveVariableReferences(const nsStyleStructID aSID, + nsRuleData* aRuleData, + nsStyleContext* aContext); + + const void* + WalkRuleTree(const nsStyleStructID aSID, nsStyleContext* aContext); + + const void* + ComputeDisplayData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeVisibilityData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeFontData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeColorData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeBackgroundData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeMarginData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeBorderData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputePaddingData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeOutlineData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeListData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputePositionData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeTableData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeTableBorderData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeContentData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeQuotesData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeTextData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeTextResetData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeUserInterfaceData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, + nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeUIResetData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeXULData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeColumnData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeSVGData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeSVGResetData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + const void* + ComputeVariablesData(void* aStartStruct, + const nsRuleData* aRuleData, + nsStyleContext* aContext, nsRuleNode* aHighestNode, + RuleDetail aRuleDetail, + const bool aCanStoreInRuleTree); + + // helpers for |ComputeFontData| that need access to |mNoneBits|: + static void SetFontSize(nsPresContext* aPresContext, + const nsRuleData* aRuleData, + const nsStyleFont* aFont, + const nsStyleFont* aParentFont, + nscoord* aSize, + const nsFont& aSystemFont, + nscoord aParentSize, + nscoord aScriptLevelAdjustedParentSize, + bool aUsedStartStruct, + bool aAtRoot, + bool& aCanStoreInRuleTree); + + static void SetFont(nsPresContext* aPresContext, + nsStyleContext* aContext, + uint8_t aGenericFontID, + const nsRuleData* aRuleData, + const nsStyleFont* aParentFont, + nsStyleFont* aFont, + bool aStartStruct, + bool& aCanStoreInRuleTree); + + static void SetGenericFont(nsPresContext* aPresContext, + nsStyleContext* aContext, + uint8_t aGenericFontID, + nsStyleFont* aFont); + + void AdjustLogicalBoxProp(nsStyleContext* aContext, + const nsCSSValue& aLTRSource, + const nsCSSValue& aRTLSource, + const nsCSSValue& aLTRLogicalValue, + const nsCSSValue& aRTLLogicalValue, + mozilla::css::Side aSide, + nsCSSRect& aValueRect, + bool& aCanStoreInRuleTree); + + inline RuleDetail CheckSpecifiedProperties(const nsStyleStructID aSID, + const nsRuleData* aRuleData); + + already_AddRefed + GetShadowData(const nsCSSValueList* aList, + nsStyleContext* aContext, + bool aIsBoxShadow, + bool& aCanStoreInRuleTree); + bool SetStyleFilterToCSSValue(nsStyleFilter* aStyleFilter, + const nsCSSValue& aValue, + nsStyleContext* aStyleContext, + nsPresContext* aPresContext, + bool& aCanStoreInRuleTree); + +private: + nsRuleNode(nsPresContext* aPresContext, nsRuleNode* aParent, + nsIStyleRule* aRule, uint8_t aLevel, bool aIsImportant); + ~nsRuleNode(); + +public: + static nsRuleNode* CreateRootNode(nsPresContext* aPresContext); + + static void EnsureBlockDisplay(uint8_t& display, + bool aConvertListItem = false); + + // Transition never returns null; on out of memory it'll just return |this|. + nsRuleNode* Transition(nsIStyleRule* aRule, uint8_t aLevel, + bool aIsImportantRule); + nsRuleNode* GetParent() const { return mParent; } + bool IsRoot() const { return mParent == nullptr; } + + // These uint8_ts are really nsStyleSet::sheetType values. + uint8_t GetLevel() const { + NS_ASSERTION(!IsRoot(), "can't call on root"); + return (mDependentBits & NS_RULE_NODE_LEVEL_MASK) >> + NS_RULE_NODE_LEVEL_SHIFT; + } + bool IsImportantRule() const { + NS_ASSERTION(!IsRoot(), "can't call on root"); + return (mDependentBits & NS_RULE_NODE_IS_IMPORTANT) != 0; + } + + /** + * Has this rule node at some time in its lifetime been the mRuleNode + * of some style context (as opposed to only being the ancestor of + * some style context's mRuleNode)? + */ + void SetUsedDirectly(); + bool IsUsedDirectly() const { + return (mDependentBits & NS_RULE_NODE_USED_DIRECTLY) != 0; + } + + // NOTE: Does not |AddRef|. Null only for the root. + nsIStyleRule* GetRule() const { return mRule; } + // NOTE: Does not |AddRef|. Never null. + nsPresContext* PresContext() const { return mPresContext; } + + const void* GetStyleData(nsStyleStructID aSID, + nsStyleContext* aContext, + bool aComputeData); + + #define STYLE_STRUCT(name_, checkdata_cb_) \ + const nsStyle##name_* GetStyle##name_(nsStyleContext* aContext, \ + bool aComputeData); + #include "nsStyleStructList.h" + #undef STYLE_STRUCT + + /* + * Garbage collection. Mark walks up the tree, marking any unmarked + * ancestors until it reaches a marked one. Sweep recursively sweeps + * the children, destroys any that are unmarked, and clears marks, + * returning true if the node on which it was called was destroyed. + */ + void Mark(); + bool Sweep(); + + static bool + HasAuthorSpecifiedRules(nsStyleContext* aStyleContext, + uint32_t ruleTypeMask, + bool aAuthorColorsAllowed); + + // Expose this so media queries can use it + static nscoord CalcLengthWithInitialFont(nsPresContext* aPresContext, + const nsCSSValue& aValue); + // Expose this so nsTransformFunctions can use it. + static nscoord CalcLength(const nsCSSValue& aValue, + nsStyleContext* aStyleContext, + nsPresContext* aPresContext, + bool& aCanStoreInRuleTree); + + struct ComputedCalc { + nscoord mLength; + float mPercent; + + ComputedCalc(nscoord aLength, float aPercent) + : mLength(aLength), mPercent(aPercent) {} + }; + static ComputedCalc + SpecifiedCalcToComputedCalc(const nsCSSValue& aValue, + nsStyleContext* aStyleContext, + nsPresContext* aPresContext, + bool& aCanStoreInRuleTree); + + // Compute the value of an nsStyleCoord that IsCalcUnit(). + // (Values that don't require aPercentageBasis should be handled + // inside nsRuleNode rather than through this API.) + static nscoord ComputeComputedCalc(const nsStyleCoord& aCoord, + nscoord aPercentageBasis); + + // Compute the value of an nsStyleCoord that is either a coord, a + // percent, or a calc expression. + static nscoord ComputeCoordPercentCalc(const nsStyleCoord& aCoord, + nscoord aPercentageBasis); + + // Return whether the rule tree for which this node is the root has + // cached data such that we need to do dynamic change handling for + // changes that change the results of media queries or require + // rebuilding all style data. + bool TreeHasCachedData() const { + NS_ASSERTION(IsRoot(), "should only be called on root of rule tree"); + return HaveChildren() || mStyleData.mInheritedData || mStyleData.mResetData; + } + + bool NodeHasCachedData(const nsStyleStructID aSID) { + return !!mStyleData.GetStyleData(aSID); + } + + static void ComputeFontFeatures(const nsCSSValuePairList *aFeaturesList, + nsTArray& aFeatureSettings); + + static nscoord CalcFontPointSize(int32_t aHTMLSize, int32_t aBasePointSize, + nsPresContext* aPresContext, + nsFontSizeType aFontSizeType = eFontSize_HTML); + + static nscoord FindNextSmallerFontSize(nscoord aFontSize, int32_t aBasePointSize, + nsPresContext* aPresContext, + nsFontSizeType aFontSizeType = eFontSize_HTML); + + static nscoord FindNextLargerFontSize(nscoord aFontSize, int32_t aBasePointSize, + nsPresContext* aPresContext, + nsFontSizeType aFontSizeType = eFontSize_HTML); + + /** + * @param aValue The color value, returned from nsCSSParser::ParseColorString + * @param aPresContext Presentation context whose preferences are used + * for certain enumerated colors + * @param aStyleContext Style context whose color is used for 'currentColor' + * + * @note aPresContext and aStyleContext may be null, but in that case, fully + * opaque black will be returned for the values that rely on these + * objects to compute the color. (For example, -moz-hyperlinktext.) + * + * @return false if we fail to extract a color; this will not happen if both + * aPresContext and aStyleContext are non-null + */ + static bool ComputeColor(const nsCSSValue& aValue, + nsPresContext* aPresContext, + nsStyleContext* aStyleContext, + nscolor& aResult); +}; + +#endif