gecko-dev/layout/style/nsStyleSet.h

546 lines
21 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/. */
/*
* the container for the style sheets that apply to a presentation, and
* the internal API that the style system exposes for creating (and
* potentially re-creating) style contexts
*/
#ifndef nsStyleSet_h_
#define nsStyleSet_h_
#include "mozilla/Attributes.h"
#include "mozilla/CSSStyleSheet.h"
#include "mozilla/MemoryReporting.h"
#include "nsIStyleRuleProcessor.h"
#include "nsBindingManager.h"
#include "nsRuleNode.h"
#include "nsTArray.h"
#include "nsCOMArray.h"
#include "nsAutoPtr.h"
#include "nsIStyleRule.h"
#include "nsCSSPseudoElements.h"
class gfxFontFeatureValueSet;
class nsCSSFontFaceRule;
class nsCSSKeyframesRule;
class nsCSSFontFeatureValuesRule;
class nsCSSPageRule;
class nsCSSCounterStyleRule;
class nsRuleWalker;
struct ElementDependentRuleProcessorData;
struct TreeMatchContext;
namespace mozilla {
class EventStates;
} // namespace mozilla
class nsEmptyStyleRule MOZ_FINAL : public nsIStyleRule
{
private:
~nsEmptyStyleRule() {}
public:
NS_DECL_ISUPPORTS
virtual void MapRuleInfoInto(nsRuleData* aRuleData) MOZ_OVERRIDE;
#ifdef DEBUG
virtual void List(FILE* out = stdout, int32_t aIndent = 0) const MOZ_OVERRIDE;
#endif
};
class nsInitialStyleRule MOZ_FINAL : public nsIStyleRule
{
private:
~nsInitialStyleRule() {}
public:
NS_DECL_ISUPPORTS
virtual void MapRuleInfoInto(nsRuleData* aRuleData) MOZ_OVERRIDE;
#ifdef DEBUG
virtual void List(FILE* out = stdout, int32_t aIndent = 0) const MOZ_OVERRIDE;
#endif
};
class nsDisableTextZoomStyleRule MOZ_FINAL : public nsIStyleRule
{
private:
~nsDisableTextZoomStyleRule() {}
public:
NS_DECL_ISUPPORTS
virtual void MapRuleInfoInto(nsRuleData* aRuleData) MOZ_OVERRIDE;
#ifdef DEBUG
virtual void List(FILE* out = stdout, int32_t aIndent = 0) const MOZ_OVERRIDE;
#endif
};
// The style set object is created by the document viewer and ownership is
// then handed off to the PresShell. Only the PresShell should delete a
// style set.
class nsStyleSet
{
public:
nsStyleSet();
size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
void Init(nsPresContext *aPresContext);
nsRuleNode* GetRuleTree() { return mRuleTree; }
// enable / disable the Quirk style sheet
void EnableQuirkStyleSheet(bool aEnable);
// get a style context for a non-pseudo frame.
already_AddRefed<nsStyleContext>
ResolveStyleFor(mozilla::dom::Element* aElement,
nsStyleContext* aParentContext);
already_AddRefed<nsStyleContext>
ResolveStyleFor(mozilla::dom::Element* aElement,
nsStyleContext* aParentContext,
TreeMatchContext& aTreeMatchContext);
// Get a style context (with the given parent) for the
// sequence of style rules in the |aRules| array.
already_AddRefed<nsStyleContext>
ResolveStyleForRules(nsStyleContext* aParentContext,
const nsTArray< nsCOMPtr<nsIStyleRule> > &aRules);
// Get a style context that represents aBaseContext, but as though
// it additionally matched the rules in the aRules array (in that
// order, as more specific than any other rules).
//
// One of the following must hold:
// 1. The resulting style context must be used only on a temporary
// basis, and it must never be put into the style context tree
// (and, in particular, we must never call
// ResolveStyleWithReplacement with it as the old context, which
// might happen if it is put in the style context tree), or
// 2. The additional rules must be appropriate for the transitions
// level of the cascade, which is the highest level of the cascade.
// (This is the case for one current caller, the cover rule used
// for CSS transitions.)
already_AddRefed<nsStyleContext>
ResolveStyleByAddingRules(nsStyleContext* aBaseContext,
const nsCOMArray<nsIStyleRule> &aRules);
// Resolve style by making replacements in the list of style rules as
// described by aReplacements, but otherwise maintaining the status
// quo.
// aPseudoElement must follow the same rules as for
// ResolvePseudoElementStyle, and be null for non-pseudo-element cases
enum { // flags for aFlags
// Skip starting CSS animations that result from the style.
eSkipStartingAnimations = (1<<0),
};
already_AddRefed<nsStyleContext>
ResolveStyleWithReplacement(mozilla::dom::Element* aElement,
mozilla::dom::Element* aPseudoElement,
nsStyleContext* aNewParentContext,
nsStyleContext* aOldStyleContext,
nsRestyleHint aReplacements,
uint32_t aFlags = 0);
// Resolve style by returning a style context with the specified
// animation data removed. It is allowable to remove all animation
// data with eRestyle_AllHintsWithAnimations, or by using any other
// hints that are allowed by ResolveStyleWithReplacement.
already_AddRefed<nsStyleContext>
ResolveStyleWithoutAnimation(mozilla::dom::Element* aElement,
nsStyleContext* aStyleContext,
nsRestyleHint aWhichToRemove);
// Get a style context for a non-element (which no rules will match),
// such as text nodes, placeholder frames, and the nsFirstLetterFrame
// for everything after the first letter.
//
// Perhaps this should go away and we shouldn't even create style
// contexts for such content nodes. However, not doing any rule
// matching for them is a first step.
already_AddRefed<nsStyleContext>
ResolveStyleForNonElement(nsStyleContext* aParentContext);
// Get a style context for a pseudo-element. aParentElement must be
// non-null. aPseudoID is the nsCSSPseudoElements::Type for the
// pseudo-element. aPseudoElement must be non-null if the pseudo-element
// type is one that allows user action pseudo-classes after it or allows
// style attributes; otherwise, it is ignored.
already_AddRefed<nsStyleContext>
ResolvePseudoElementStyle(mozilla::dom::Element* aParentElement,
nsCSSPseudoElements::Type aType,
nsStyleContext* aParentContext,
mozilla::dom::Element* aPseudoElement);
// This functions just like ResolvePseudoElementStyle except that it will
// return nullptr if there are no explicit style rules for that
// pseudo element.
already_AddRefed<nsStyleContext>
ProbePseudoElementStyle(mozilla::dom::Element* aParentElement,
nsCSSPseudoElements::Type aType,
nsStyleContext* aParentContext);
already_AddRefed<nsStyleContext>
ProbePseudoElementStyle(mozilla::dom::Element* aParentElement,
nsCSSPseudoElements::Type aType,
nsStyleContext* aParentContext,
TreeMatchContext& aTreeMatchContext,
mozilla::dom::Element* aPseudoElement = nullptr);
// Get a style context for an anonymous box. aPseudoTag is the
// pseudo-tag to use and must be non-null.
already_AddRefed<nsStyleContext>
ResolveAnonymousBoxStyle(nsIAtom* aPseudoTag, nsStyleContext* aParentContext);
#ifdef MOZ_XUL
// Get a style context for a XUL tree pseudo. aPseudoTag is the
// pseudo-tag to use and must be non-null. aParentContent must be
// non-null. aComparator must be non-null.
already_AddRefed<nsStyleContext>
ResolveXULTreePseudoStyle(mozilla::dom::Element* aParentElement,
nsIAtom* aPseudoTag,
nsStyleContext* aParentContext,
nsICSSPseudoComparator* aComparator);
#endif
// 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);
// Return the winning (in the cascade) @keyframes rule for the given name.
nsCSSKeyframesRule* KeyframesRuleForName(nsPresContext* aPresContext,
const nsString& aName);
// Return the winning (in the cascade) @counter-style rule for the given name.
nsCSSCounterStyleRule* CounterStyleRuleForName(nsPresContext* aPresContext,
const nsAString& aName);
// Fetch object for looking up font feature values
already_AddRefed<gfxFontFeatureValueSet> GetFontFeatureValuesLookup();
// Append all the currently-active font feature values rules to aArray.
// Return true for success and false for failure.
bool AppendFontFeatureValuesRules(nsPresContext* aPresContext,
nsTArray<nsCSSFontFeatureValuesRule*>& aArray);
// Append all the currently-active page rules to aArray. Return
// true for success and false for failure.
bool AppendPageRules(nsPresContext* aPresContext,
nsTArray<nsCSSPageRule*>& aArray);
// Begin ignoring style context destruction, to avoid lots of unnecessary
// work on document teardown.
void BeginShutdown(nsPresContext* aPresContext);
// Free all of the data associated with this style set.
void Shutdown(nsPresContext* aPresContext);
// Notification that a style context is being destroyed.
void NotifyStyleContextDestroyed(nsPresContext* aPresContext,
nsStyleContext* aStyleContext);
// Get a new style context that lives in a different parent
// The new context will be the same as the old if the new parent is the
// same as the old parent.
// aElement should be non-null if this is a style context for an
// element or pseudo-element; in the latter case it should be the
// real element the pseudo-element is for.
already_AddRefed<nsStyleContext>
ReparentStyleContext(nsStyleContext* aStyleContext,
nsStyleContext* aNewParentContext,
mozilla::dom::Element* aElement);
// Test if style is dependent on a document state.
bool HasDocumentStateDependentStyle(nsPresContext* aPresContext,
nsIContent* aContent,
mozilla::EventStates aStateMask);
// Test if style is dependent on content state
nsRestyleHint HasStateDependentStyle(nsPresContext* aPresContext,
mozilla::dom::Element* aElement,
mozilla::EventStates aStateMask);
nsRestyleHint HasStateDependentStyle(nsPresContext* aPresContext,
mozilla::dom::Element* aElement,
nsCSSPseudoElements::Type aPseudoType,
mozilla::dom::Element* aPseudoElement,
mozilla::EventStates aStateMask);
// Test if style is dependent on the presence of an attribute.
nsRestyleHint HasAttributeDependentStyle(nsPresContext* aPresContext,
mozilla::dom::Element* aElement,
nsIAtom* aAttribute,
int32_t aModType,
bool aAttrHasChanged);
/*
* Do any processing that needs to happen as a result of a change in
* the characteristics of the medium, and return whether style rules
* may have changed as a result.
*/
bool MediumFeaturesChanged(nsPresContext* aPresContext);
// APIs for registering objects that can supply additional
// rules during processing.
void SetBindingManager(nsBindingManager* aBindingManager)
{
mBindingManager = aBindingManager;
}
// The "origins" of the CSS cascade, from lowest precedence to
// highest (for non-!important rules).
enum sheetType {
eAgentSheet, // CSS
eUserSheet, // CSS
ePresHintSheet,
eSVGAttrAnimationSheet,
eDocSheet, // CSS
eScopedDocSheet,
eStyleAttrSheet,
eOverrideSheet, // CSS
eAnimationSheet,
eTransitionSheet,
eSheetTypeCount
// be sure to keep the number of bits in |mDirty| below and in
// NS_RULE_NODE_LEVEL_MASK updated when changing the number of sheet
// types
};
// APIs to manipulate the style sheet lists. The sheets in each
// list are stored with the most significant sheet last.
nsresult AppendStyleSheet(sheetType aType, nsIStyleSheet *aSheet);
nsresult PrependStyleSheet(sheetType aType, nsIStyleSheet *aSheet);
nsresult RemoveStyleSheet(sheetType aType, nsIStyleSheet *aSheet);
nsresult ReplaceSheets(sheetType aType,
const nsCOMArray<nsIStyleSheet> &aNewSheets);
nsresult InsertStyleSheetBefore(sheetType aType, nsIStyleSheet *aNewSheet,
nsIStyleSheet *aReferenceSheet);
nsresult DirtyRuleProcessors(sheetType aType);
// Enable/Disable entire author style level (Doc, ScopedDoc & PresHint levels)
bool GetAuthorStyleDisabled();
nsresult SetAuthorStyleDisabled(bool aStyleDisabled);
int32_t SheetCount(sheetType aType) const {
return mSheets[aType].Count();
}
nsIStyleSheet* StyleSheetAt(sheetType aType, int32_t aIndex) const {
return mSheets[aType].ObjectAt(aIndex);
}
nsresult RemoveDocStyleSheet(nsIStyleSheet* aSheet);
nsresult AddDocStyleSheet(nsIStyleSheet* aSheet, nsIDocument* aDocument);
void BeginUpdate();
nsresult EndUpdate();
// Methods for reconstructing the tree; BeginReconstruct basically moves the
// old rule tree root and style context roots out of the way,
// and EndReconstruct destroys the old rule tree when we're done
nsresult BeginReconstruct();
// Note: EndReconstruct should not be called if BeginReconstruct fails
void EndReconstruct();
bool IsInRuleTreeReconstruct() const {
return mInReconstruct;
}
// Let the style set know that a particular sheet is the quirks sheet. This
// sheet must already have been added to the UA sheets. The pointer must not
// be null. This should only be called once for a given style set.
void SetQuirkStyleSheet(nsIStyleSheet* aQuirkStyleSheet);
// Return whether the rule tree 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.
// We don't care whether we have cached rule processors or whether
// they have cached rule cascades; getting the rule cascades again in
// order to do rule matching will get the correct rule cascade.
bool HasCachedStyleData() const {
return (mRuleTree && mRuleTree->TreeHasCachedData()) || !mRoots.IsEmpty();
}
// Notify the style set that a rulenode is no longer in use, or was
// just created and is not in use yet.
void RuleNodeUnused() {
++mUnusedRuleNodeCount;
}
// Notify the style set that a rulenode that wasn't in use now is
void RuleNodeInUse() {
--mUnusedRuleNodeCount;
}
mozilla::CSSStyleSheet::EnsureUniqueInnerResult EnsureUniqueInnerOnCSSSheets();
nsIStyleRule* InitialStyleRule();
private:
nsStyleSet(const nsStyleSet& aCopy) = delete;
nsStyleSet& operator=(const nsStyleSet& aCopy) = delete;
// Run mark-and-sweep GC on mRuleTree and mOldRuleTrees, based on mRoots.
void GCRuleTrees();
// Update the rule processor list after a change to the style sheet list.
nsresult GatherRuleProcessors(sheetType aType);
void AddImportantRules(nsRuleNode* aCurrLevelNode,
nsRuleNode* aLastPrevLevelNode,
nsRuleWalker* aRuleWalker);
// Move aRuleWalker forward by the appropriate rule if we need to add
// a rule due to property restrictions on pseudo-elements.
void WalkRestrictionRule(nsCSSPseudoElements::Type aPseudoType,
nsRuleWalker* aRuleWalker);
void WalkDisableTextZoomRule(mozilla::dom::Element* aElement,
nsRuleWalker* aRuleWalker);
#ifdef DEBUG
// Just like AddImportantRules except it doesn't actually add anything; it
// just asserts that there are no important rules between aCurrLevelNode and
// aLastPrevLevelNode.
void AssertNoImportantRules(nsRuleNode* aCurrLevelNode,
nsRuleNode* aLastPrevLevelNode);
// Just like AddImportantRules except it doesn't actually add anything; it
// just asserts that there are no CSS rules between aCurrLevelNode and
// aLastPrevLevelNode. Mostly useful for the preshint level.
void AssertNoCSSRules(nsRuleNode* aCurrLevelNode,
nsRuleNode* aLastPrevLevelNode);
#endif
// Enumerate the rules in a way that cares about the order of the
// rules.
// aElement is the element the rules are for. It might be null. aData
// is the closure to pass to aCollectorFunc. If aContent is not null,
// aData must be a RuleProcessorData*
void FileRules(nsIStyleRuleProcessor::EnumFunc aCollectorFunc,
RuleProcessorData* aData, mozilla::dom::Element* aElement,
nsRuleWalker* aRuleWalker);
// Enumerate all the rules in a way that doesn't care about the order
// of the rules and break out if the enumeration is halted.
void WalkRuleProcessors(nsIStyleRuleProcessor::EnumFunc aFunc,
ElementDependentRuleProcessorData* aData,
bool aWalkAllXBLStylesheets);
// Helper for ResolveStyleWithReplacement
// aPseudoElement must follow the same rules as for
// ResolvePseudoElementStyle, and be null for non-pseudo-element cases
nsRuleNode* RuleNodeWithReplacement(mozilla::dom::Element* aElement,
mozilla::dom::Element* aPseudoElement,
nsRuleNode* aOldRuleNode,
nsCSSPseudoElements::Type aPseudoType,
nsRestyleHint aReplacements);
/**
* Bit-flags that can be passed to GetContext() in its parameter 'aFlags'.
*/
enum {
eNoFlags = 0,
eIsLink = 1 << 0,
eIsVisitedLink = 1 << 1,
eDoAnimation = 1 << 2,
// Indicates that we should skip the flex/grid item specific chunk of
// ApplyStyleFixups(). This is useful if our parent has "display: flex"
// or "display: grid" but we can tell we're not going to honor that (e.g. if
// it's the outer frame of a button widget, and we're the inline frame for
// the button's label).
eSkipParentDisplayBasedStyleFixup = 1 << 3
};
already_AddRefed<nsStyleContext>
GetContext(nsStyleContext* aParentContext,
nsRuleNode* aRuleNode,
nsRuleNode* aVisitedRuleNode,
nsIAtom* aPseudoTag,
nsCSSPseudoElements::Type aPseudoType,
mozilla::dom::Element* aElementForAnimation,
uint32_t aFlags);
nsPresContext* PresContext() { return mRuleTree->PresContext(); }
// The sheets in each array in mSheets are stored with the most significant
// sheet last.
// The arrays for ePresHintSheet, eStyleAttrSheet, eTransitionSheet,
// and eAnimationSheet are always empty. (FIXME: We should reduce
// the storage needed for them.)
nsCOMArray<nsIStyleSheet> mSheets[eSheetTypeCount];
// mRuleProcessors[eScopedDocSheet] is always null; rule processors
// for scoped style sheets are stored in mScopedDocSheetRuleProcessors.
nsCOMPtr<nsIStyleRuleProcessor> mRuleProcessors[eSheetTypeCount];
// Rule processors for HTML5 scoped style sheets, one per scope.
nsTArray<nsCOMPtr<nsIStyleRuleProcessor> > mScopedDocSheetRuleProcessors;
// cached instance for enabling/disabling
nsCOMPtr<nsIStyleSheet> mQuirkStyleSheet;
nsRefPtr<nsBindingManager> mBindingManager;
nsRuleNode* mRuleTree; // This is the root of our rule tree. It is a
// lexicographic tree of matched rules that style
// contexts use to look up properties.
uint16_t mBatching;
unsigned mInShutdown : 1;
unsigned mAuthorStyleDisabled: 1;
unsigned mInReconstruct : 1;
unsigned mInitFontFeatureValuesLookup : 1;
unsigned mDirty : 10; // one dirty bit is used per sheet type
uint32_t mUnusedRuleNodeCount; // used to batch rule node GC
nsTArray<nsStyleContext*> mRoots; // style contexts with no parent
// Empty style rules to force things that restrict which properties
// apply into different branches of the rule tree.
nsRefPtr<nsEmptyStyleRule> mFirstLineRule, mFirstLetterRule, mPlaceholderRule;
// Style rule which sets all properties to their initial values for
// determining when context-sensitive values are in use.
nsRefPtr<nsInitialStyleRule> mInitialStyleRule;
// Style rule that sets the internal -x-text-zoom property on
// <svg:text> elements to disable the effect of text zooming.
nsRefPtr<nsDisableTextZoomStyleRule> mDisableTextZoomStyleRule;
// Old rule trees, which should only be non-empty between
// BeginReconstruct and EndReconstruct, but in case of bugs that cause
// style contexts to exist too long, may last longer.
nsTArray<nsRuleNode*> mOldRuleTrees;
// whether font feature values lookup object needs initialization
nsRefPtr<gfxFontFeatureValueSet> mFontFeatureValuesLookup;
};
#ifdef MOZILLA_INTERNAL_API
inline
void nsRuleNode::AddRef()
{
if (mRefCnt++ == 0 && !IsRoot()) {
mPresContext->StyleSet()->RuleNodeInUse();
}
}
inline
void nsRuleNode::Release()
{
if (--mRefCnt == 0 && !IsRoot()) {
mPresContext->StyleSet()->RuleNodeUnused();
}
}
#endif
#endif