gecko-dev/layout/style/nsRuleNode.h

778 lines
30 KiB
C++

/* -*- 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 "mozilla/StandardInteger.h"
class nsStyleContext;
struct nsRuleData;
class nsIStyleRule;
struct nsCSSValueList;
class nsCSSValue;
struct nsCSSRect;
class nsStyleCoord;
struct nsCSSValuePairList;
template <nsStyleStructID MinIndex, nsStyleStructID Count>
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<nsStyleStructID_Inherited_Start,
nsStyleStructID_Inherited_Count> mStyleStructs;
void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
return aContext->AllocateFromShell(sz);
}
void DestroyStructs(uint32_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<nsStyle##name*>(name##Data)->Destroy(aContext);
#define STYLE_STRUCT_RESET(name, checkdata_cb)
#include "nsStyleStructList.h"
#undef STYLE_STRUCT_INHERITED
#undef STYLE_STRUCT_RESET
}
void Destroy(uint32_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<nsStyleStructID_Reset_Start,
nsStyleStructID_Reset_Count> 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(uint32_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<nsStyle##name*>(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 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<nsStyle##name_*>( \
mInheritedData->mStyleStructs[eStyleStruct_##name_]) : nullptr; \
}
#define STYLE_STRUCT_RESET(name_, checkdata_cb_) \
nsStyle##name_ * NS_FASTCALL GetStyle##name_ () { \
return mResetData ? static_cast<nsStyle##name_*>( \
mResetData->mStyleStructs[eStyleStruct_##name_]) : nullptr; \
}
#include "nsStyleStructList.h"
#undef STYLE_STRUCT_RESET
#undef STYLE_STRUCT_INHERITED
void Destroy(uint32_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 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);
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);
// 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<nsCSSShadowArray>
GetShadowData(const nsCSSValueList* aList,
nsStyleContext* aContext,
bool aIsBoxShadow,
bool& inherited);
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);
// 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<gfxFontFeature>& 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