gecko-dev/layout/style/nsIStyleRuleProcessor.h

290 lines
12 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* L. David Baron <dbaron@dbaron.org>, Mozilla Corporation
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* internal abstract interface for containers (roughly origins within
* the CSS cascade) that provide style rules matching an element or
* pseudo-element
*/
#ifndef nsIStyleRuleProcessor_h___
#define nsIStyleRuleProcessor_h___
#include <stdio.h>
#include "nsISupports.h"
#include "nsPresContext.h" // for nsCompatability
#include "nsILinkHandler.h"
#include "nsString.h"
#include "nsChangeHint.h"
class nsIStyleSheet;
class nsPresContext;
class nsIContent;
class nsIAtom;
class nsICSSPseudoComparator;
class nsRuleWalker;
class nsAttrValue;
// The implementation of the constructor and destructor are currently in
// nsCSSRuleProcessor.cpp.
struct RuleProcessorData {
RuleProcessorData(nsPresContext* aPresContext,
nsIContent* aContent,
nsRuleWalker* aRuleWalker,
nsCompatibility* aCompat = nsnull);
// NOTE: not |virtual|
~RuleProcessorData();
// This should be used for all heap-allocation of RuleProcessorData
static RuleProcessorData* Create(nsPresContext* aPresContext,
nsIContent* aContent,
nsRuleWalker* aRuleWalker,
nsCompatibility aCompat)
{
if (NS_LIKELY(aPresContext)) {
return new (aPresContext) RuleProcessorData(aPresContext, aContent,
aRuleWalker, &aCompat);
}
return new RuleProcessorData(aPresContext, aContent, aRuleWalker,
&aCompat);
}
void Destroy() {
nsPresContext * pc = mPresContext;
if (NS_LIKELY(pc)) {
this->~RuleProcessorData();
pc->FreeToShell(sizeof(RuleProcessorData), this);
return;
}
delete this;
}
// For placement new
void* operator new(size_t sz, RuleProcessorData* aSlot) CPP_THROW_NEW {
return aSlot;
}
private:
void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
return aContext->AllocateFromShell(sz);
}
void* operator new(size_t sz) CPP_THROW_NEW {
return ::operator new(sz);
}
public:
const nsString* GetLang();
// Returns a 1-based index of the child in its parent. If the child
// is not in its parent's child list (i.e., it is anonymous content),
// returns 0.
// If aCheckEdgeOnly is true, the function will return 1 if the result
// is 1, and something other than 1 (maybe or maybe not a valid
// result) otherwise.
PRInt32 GetNthIndex(PRBool aIsOfType, PRBool aIsFromEnd,
PRBool aCheckEdgeOnly);
nsPresContext* mPresContext;
nsIContent* mContent; // weak ref
nsIContent* mParentContent; // if content, content->GetParent(); weak ref
nsRuleWalker* mRuleWalker; // Used to add rules to our results.
nsIContent* mScopedRoot; // Root of scoped stylesheet (set and unset by the supplier of the scoped stylesheet
nsIAtom* mContentTag; // if content, then content->GetTag()
nsIAtom* mContentID; // if styled content, then weak reference to styledcontent->GetID()
PRPackedBool mIsHTMLContent; // if content, then does QI on HTMLContent, true or false
PRPackedBool mIsLink; // if content, calls nsStyleUtil::IsHTMLLink or nsStyleUtil::IsLink
PRPackedBool mHasAttributes; // if content, content->GetAttrCount() > 0
nsCompatibility mCompatMode; // Possibly remove use of this in SelectorMatches?
nsLinkState mLinkState; // if a link, this is the state, otherwise unknown
PRInt32 mEventState; // if content, eventStateMgr->GetContentState()
PRInt32 mNameSpaceID; // if content, content->GetNameSapce()
const nsAttrValue* mClasses; // if styled content, styledcontent->GetClasses()
// mPreviousSiblingData and mParentData are always RuleProcessorData
// and never a derived class. They are allocated lazily, when
// selectors require matching of prior siblings or ancestors.
RuleProcessorData* mPreviousSiblingData;
RuleProcessorData* mParentData;
protected:
nsString *mLanguage; // NULL means we haven't found out the language yet
// This node's index for :nth-child(), :nth-last-child(),
// :nth-of-type(), :nth-last-of-type(). If -2, needs to be computed.
// If -1, needs to be computed but known not to be 1.
// If 0, the node is not at any index in its parent.
// The first subscript is 0 for -child and 1 for -of-type, the second
// subscript is 0 for nth- and 1 for nth-last-.
PRInt32 mNthIndices[2][2];
};
struct ElementRuleProcessorData : public RuleProcessorData {
ElementRuleProcessorData(nsPresContext* aPresContext,
nsIContent* aContent,
nsRuleWalker* aRuleWalker)
: RuleProcessorData(aPresContext,aContent,aRuleWalker)
{
NS_PRECONDITION(aPresContext, "null pointer");
NS_PRECONDITION(aContent, "null pointer");
NS_PRECONDITION(aRuleWalker, "null pointer");
}
};
struct PseudoRuleProcessorData : public RuleProcessorData {
PseudoRuleProcessorData(nsPresContext* aPresContext,
nsIContent* aParentContent,
nsIAtom* aPseudoTag,
nsICSSPseudoComparator* aComparator,
nsRuleWalker* aRuleWalker)
: RuleProcessorData(aPresContext, aParentContent, aRuleWalker)
{
NS_PRECONDITION(aPresContext, "null pointer");
NS_PRECONDITION(aPseudoTag, "null pointer");
NS_PRECONDITION(aRuleWalker, "null pointer");
mPseudoTag = aPseudoTag;
mComparator = aComparator;
}
nsIAtom* mPseudoTag;
nsICSSPseudoComparator* mComparator;
};
struct StateRuleProcessorData : public RuleProcessorData {
StateRuleProcessorData(nsPresContext* aPresContext,
nsIContent* aContent,
PRInt32 aStateMask)
: RuleProcessorData(aPresContext, aContent, nsnull),
mStateMask(aStateMask)
{
NS_PRECONDITION(aPresContext, "null pointer");
NS_PRECONDITION(aContent, "null pointer");
}
const PRInt32 mStateMask; // |HasStateDependentStyle| for which state(s)?
// Constants defined in nsIEventStateManager.h .
};
struct AttributeRuleProcessorData : public RuleProcessorData {
AttributeRuleProcessorData(nsPresContext* aPresContext,
nsIContent* aContent,
nsIAtom* aAttribute,
PRInt32 aModType,
PRUint32 aStateMask)
: RuleProcessorData(aPresContext, aContent, nsnull),
mAttribute(aAttribute),
mModType(aModType),
mStateMask(aStateMask)
{
NS_PRECONDITION(aPresContext, "null pointer");
NS_PRECONDITION(aContent, "null pointer");
}
nsIAtom* mAttribute; // |HasAttributeDependentStyle| for which attribute?
PRInt32 mModType; // The type of modification (see nsIDOMMutationEvent).
PRUint32 mStateMask; // The states that changed with the attr change.
};
// IID for the nsIStyleRuleProcessor interface {015575fe-7b6c-11d3-ba05-001083023c2b}
#define NS_ISTYLE_RULE_PROCESSOR_IID \
{0x015575fe, 0x7b6c, 0x11d3, {0xba, 0x05, 0x00, 0x10, 0x83, 0x02, 0x3c, 0x2b}}
/* The style rule processor interface is a mechanism to separate the matching
* of style rules from style sheet instances.
* Simple style sheets can and will act as their own processor.
* Sheets where rule ordering interlaces between multiple sheets, will need to
* share a single rule processor between them (CSS sheets do this for cascading order)
*
* @see nsIStyleRule (for significantly more detailed comments)
*/
class nsIStyleRuleProcessor : public nsISupports {
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_ISTYLE_RULE_PROCESSOR_IID)
// Shorthand for:
// nsCOMArray<nsIStyleRuleProcessor>::nsCOMArrayEnumFunc
typedef PRBool (* EnumFunc)(nsIStyleRuleProcessor*, void*);
/**
* Find the |nsIStyleRule|s matching the given content node and
* position the given |nsRuleWalker| at the |nsRuleNode| in the rule
* tree representing that ordered list of rules (with higher
* precedence being farther from the root of the lexicographic tree).
*/
NS_IMETHOD RulesMatching(ElementRuleProcessorData* aData) = 0;
/**
* Just like the previous |RulesMatching|, except for a given content
* node <em>and pseudo-element</em>.
*/
NS_IMETHOD RulesMatching(PseudoRuleProcessorData* aData) = 0;
/**
* Return how (as described by nsReStyleHint) style can depend on a
* change of the given content state on the given content node. This
* test is used for optimization only, and may err on the side of
* reporting more dependencies than really exist.
*
* Event states are defined in nsIEventStateManager.h.
*/
NS_IMETHOD HasStateDependentStyle(StateRuleProcessorData* aData,
nsReStyleHint* aResult) = 0;
/**
* Return how (as described by nsReStyleHint) style can depend on the
* presence or value of the given attribute for the given content
* node. This test is used for optimization only, and may err on the
* side of reporting more dependencies than really exist.
*/
NS_IMETHOD HasAttributeDependentStyle(AttributeRuleProcessorData* aData,
nsReStyleHint* aResult) = 0;
/**
* Do any processing that needs to happen as a result of a change in
* the characteristics of the medium, and return whether this rule
* processor's rules have changed (e.g., because of media queries).
*/
NS_IMETHOD MediumFeaturesChanged(nsPresContext* aPresContext,
PRBool* aRulesChanged) = 0;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsIStyleRuleProcessor,
NS_ISTYLE_RULE_PROCESSOR_IID)
#endif /* nsIStyleRuleProcessor_h___ */