gecko-dev/layout/style/nsCSSRuleProcessor.h

293 lines
10 KiB
C++

/* -*- 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
*/
#ifndef nsCSSRuleProcessor_h_
#define nsCSSRuleProcessor_h_
#include "mozilla/Attributes.h"
#include "mozilla/EventStates.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/RefCountType.h"
#include "mozilla/SheetType.h"
#include "mozilla/UniquePtr.h"
#include "nsExpirationTracker.h"
#include "nsIMediaList.h"
#include "nsIStyleRuleProcessor.h"
#include "nsRuleWalker.h"
#include "nsTArray.h"
struct CascadeEnumData;
struct ElementDependentRuleProcessorData;
struct nsCSSSelector;
struct nsCSSSelectorList;
struct nsFontFaceRuleContainer;
struct RuleCascadeData;
struct TreeMatchContext;
class nsCSSKeyframesRule;
class nsCSSPageRule;
class nsCSSFontFeatureValuesRule;
class nsCSSCounterStyleRule;
namespace mozilla {
class CSSStyleSheet;
enum class CSSPseudoElementType : uint8_t;
namespace css {
class DocumentRule;
} // namespace css
} // namespace mozilla
/**
* The CSS style rule processor provides a mechanism for sibling style
* sheets to combine their rule processing in order to allow proper
* cascading to happen.
*
* CSS style rule processors keep a live reference on all style sheets
* bound to them. The CSS style sheets keep a weak reference to all the
* processors that they are bound to (many to many). The CSS style sheet
* is told when the rule processor is going away (via DropRuleProcessor).
*/
class nsCSSRuleProcessor: public nsIStyleRuleProcessor {
public:
typedef nsTArray<RefPtr<mozilla::CSSStyleSheet>> sheet_array_type;
// aScopeElement must be non-null iff aSheetType is
// SheetType::ScopedDoc.
// aPreviousCSSRuleProcessor is the rule processor (if any) that this
// one is replacing.
nsCSSRuleProcessor(const sheet_array_type& aSheets,
mozilla::SheetType aSheetType,
mozilla::dom::Element* aScopeElement,
nsCSSRuleProcessor* aPreviousCSSRuleProcessor,
bool aIsShared = false);
nsCSSRuleProcessor(sheet_array_type&& aSheets,
mozilla::SheetType aSheetType,
mozilla::dom::Element* aScopeElement,
nsCSSRuleProcessor* aPreviousCSSRuleProcessor,
bool aIsShared = false);
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(nsCSSRuleProcessor)
public:
nsresult ClearRuleCascades();
static void Startup();
static void Shutdown();
static void FreeSystemMetrics();
static bool HasSystemMetric(nsIAtom* aMetric);
/*
* Returns true if the given aElement matches one of the
* selectors in aSelectorList. Note that this method will assume
* the given aElement is not a relevant link. aSelectorList must not
* include any pseudo-element selectors. aSelectorList is allowed
* to be null; in this case false will be returned.
*/
static bool SelectorListMatches(mozilla::dom::Element* aElement,
TreeMatchContext& aTreeMatchContext,
nsCSSSelectorList* aSelectorList);
/*
* Helper to get the content state for a content node. This may be
* slightly adjusted from IntrinsicState().
*/
static mozilla::EventStates GetContentState(
mozilla::dom::Element* aElement,
const TreeMatchContext& aTreeMatchContext);
/*
* Helper to get the content state for :visited handling for an element
*/
static mozilla::EventStates GetContentStateForVisitedHandling(
mozilla::dom::Element* aElement,
const TreeMatchContext& aTreeMatchContext,
nsRuleWalker::VisitedHandlingType aVisitedHandling,
bool aIsRelevantLink);
/*
* Helper to test whether a node is a link
*/
static bool IsLink(mozilla::dom::Element* aElement);
/**
* Returns true if the given aElement matches aSelector.
* Like nsCSSRuleProcessor.cpp's SelectorMatches (and unlike
* SelectorMatchesTree), this does not check an entire selector list
* separated by combinators.
*
* :visited and :link will match both visited and non-visited links,
* as if aTreeMatchContext->mVisitedHandling were eLinksVisitedOrUnvisited.
*
* aSelector is restricted to not containing pseudo-elements.
*/
static bool RestrictedSelectorMatches(mozilla::dom::Element* aElement,
nsCSSSelector* aSelector,
TreeMatchContext& aTreeMatchContext);
// nsIStyleRuleProcessor
virtual void RulesMatching(ElementRuleProcessorData* aData) override;
virtual void RulesMatching(PseudoElementRuleProcessorData* aData) override;
virtual void RulesMatching(AnonBoxRuleProcessorData* aData) override;
#ifdef MOZ_XUL
virtual void RulesMatching(XULTreeRuleProcessorData* aData) override;
#endif
virtual nsRestyleHint HasStateDependentStyle(StateRuleProcessorData* aData) override;
virtual nsRestyleHint HasStateDependentStyle(PseudoElementStateRuleProcessorData* aData) override;
virtual bool HasDocumentStateDependentStyle(StateRuleProcessorData* aData) override;
virtual nsRestyleHint
HasAttributeDependentStyle(AttributeRuleProcessorData* aData,
mozilla::RestyleHintData& aRestyleHintDataResult)
override;
virtual bool MediumFeaturesChanged(nsPresContext* aPresContext) override;
/**
* If this rule processor currently has a substantive media query
* result cache key, return a copy of it.
*/
mozilla::UniquePtr<nsMediaQueryResultCacheKey> CloneMQCacheKey();
virtual size_t SizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf)
const MOZ_MUST_OVERRIDE override;
virtual size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf)
const MOZ_MUST_OVERRIDE override;
// Append all the currently-active font face rules to aArray. Return
// true for success and false for failure.
bool AppendFontFaceRules(nsPresContext* aPresContext,
nsTArray<nsFontFaceRuleContainer>& aArray);
nsCSSKeyframesRule* KeyframesRuleForName(nsPresContext* aPresContext,
const nsString& aName);
nsCSSCounterStyleRule* CounterStyleRuleForName(nsPresContext* aPresContext,
const nsAString& aName);
bool AppendPageRules(nsPresContext* aPresContext,
nsTArray<nsCSSPageRule*>& aArray);
bool AppendFontFeatureValuesRules(nsPresContext* aPresContext,
nsTArray<nsCSSFontFeatureValuesRule*>& aArray);
/**
* Returns the scope element for the scoped style sheets this rule
* processor is for. If this is not a rule processor for scoped style
* sheets, it returns null.
*/
mozilla::dom::Element* GetScopeElement() const { return mScopeElement; }
void TakeDocumentRulesAndCacheKey(
nsPresContext* aPresContext,
nsTArray<mozilla::css::DocumentRule*>& aDocumentRules,
nsDocumentRuleResultCacheKey& aDocumentRuleResultCacheKey);
bool IsShared() const { return mIsShared; }
nsExpirationState* GetExpirationState() { return &mExpirationState; }
void AddStyleSetRef();
void ReleaseStyleSetRef();
void SetInRuleProcessorCache(bool aVal) {
MOZ_ASSERT(mIsShared);
mInRuleProcessorCache = aVal;
}
bool IsInRuleProcessorCache() const { return mInRuleProcessorCache; }
bool IsUsedByMultipleStyleSets() const { return mStyleSetRefCnt > 1; }
#ifdef XP_WIN
// Cached theme identifier for the moz-windows-theme media query.
static uint8_t GetWindowsThemeIdentifier();
static void SetWindowsThemeIdentifier(uint8_t aId) {
sWinThemeId = aId;
}
#endif
struct StateSelector {
StateSelector(mozilla::EventStates aStates, nsCSSSelector* aSelector)
: mStates(aStates),
mSelector(aSelector)
{}
mozilla::EventStates mStates;
nsCSSSelector* mSelector;
};
protected:
virtual ~nsCSSRuleProcessor();
private:
static bool CascadeSheet(mozilla::CSSStyleSheet* aSheet,
CascadeEnumData* aData);
RuleCascadeData* GetRuleCascade(nsPresContext* aPresContext);
void RefreshRuleCascade(nsPresContext* aPresContext);
nsRestyleHint HasStateDependentStyle(ElementDependentRuleProcessorData* aData,
mozilla::dom::Element* aStatefulElement,
mozilla::CSSPseudoElementType aPseudoType,
mozilla::EventStates aStateMask);
void ClearSheets();
// The sheet order here is the same as in nsStyleSet::mSheets
sheet_array_type mSheets;
// active first, then cached (most recent first)
RuleCascadeData* mRuleCascades;
// If we cleared our mRuleCascades or replaced a previous rule
// processor, this is the media query result cache key that was used
// before we lost the old rule cascades.
mozilla::UniquePtr<nsMediaQueryResultCacheKey> mPreviousCacheKey;
// The last pres context for which GetRuleCascades was called.
nsPresContext *mLastPresContext;
// The scope element for this rule processor's scoped style sheets.
// Only used if mSheetType == nsStyleSet::eScopedDocSheet.
RefPtr<mozilla::dom::Element> mScopeElement;
nsTArray<mozilla::css::DocumentRule*> mDocumentRules;
nsDocumentRuleResultCacheKey mDocumentCacheKey;
nsExpirationState mExpirationState;
MozRefCountType mStyleSetRefCnt;
// type of stylesheet using this processor
mozilla::SheetType mSheetType;
const bool mIsShared;
// Whether we need to build up mDocumentCacheKey and mDocumentRules as
// we build a RuleCascadeData. Is true only for shared rule processors
// and only before we build the first RuleCascadeData. See comment in
// RefreshRuleCascade for why.
bool mMustGatherDocumentRules;
bool mInRuleProcessorCache;
#ifdef DEBUG
bool mDocumentRulesAndCacheKeyValid;
#endif
#ifdef XP_WIN
static uint8_t sWinThemeId;
#endif
};
#endif /* nsCSSRuleProcessor_h_ */