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- /* -*- 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):
- * David Hyatt <hyatt@netscape.com>
- * Pierre Phaneuf <pp@ludusdesign.com>
- *
- * 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 ***** */
-
- #ifndef _nsStyleContext_h_
- #define _nsStyleContext_h_
-
- #include "nsRuleNode.h"
- #include "nsIAtom.h"
-
- class nsPresContext;
-
- /**
- * An nsStyleContext represents the computed style data for an element.
- * The computed style data are stored in a set of structs (see
- * nsStyleStruct.h) that are cached either on the style context or in
- * the rule tree (see nsRuleNode.h for a description of this caching and
- * how the cached structs are shared).
- *
- * Since the data in |nsIStyleRule|s and |nsRuleNode|s are immutable
- * (with a few exceptions, like system color changes), the data in an
- * nsStyleContext are also immutable (with the additional exception of
- * GetUniqueStyleData). When style data change,
- * nsFrameManager::ReResolveStyleContext creates a new style context.
- *
- * Style contexts are reference counted. References are generally held
- * by:
- * 1. the |nsIFrame|s that are using the style context and
- * 2. any *child* style contexts (this might be the reverse of
- * expectation, but it makes sense in this case)
- * Style contexts participate in the mark phase of rule node garbage
- * collection.
- */
-
- class nsStyleContext
- {
- public:
- nsStyleContext(nsStyleContext* aParent, nsIAtom* aPseudoTag,
- nsRuleNode* aRuleNode, nsPresContext* aPresContext) NS_HIDDEN;
- ~nsStyleContext() NS_HIDDEN;
-
- NS_HIDDEN_(void*) operator new(size_t sz, nsPresContext* aPresContext) CPP_THROW_NEW;
- NS_HIDDEN_(void) Destroy();
-
- nsrefcnt AddRef() {
- ++mRefCnt;
- NS_LOG_ADDREF(this, mRefCnt, "nsStyleContext", sizeof(nsStyleContext));
- return mRefCnt;
- }
-
- nsrefcnt Release() {
- --mRefCnt;
- NS_LOG_RELEASE(this, mRefCnt, "nsStyleContext");
- if (mRefCnt == 0) {
- Destroy();
- return 0;
- }
- return mRefCnt;
- }
-
- nsPresContext* PresContext() const { return mRuleNode->GetPresContext(); }
-
- nsStyleContext* GetParent() const { return mParent; }
-
- nsStyleContext* GetFirstChild() const { return mChild; }
-
- nsIAtom* GetPseudoType() const { return mPseudoTag; }
-
- NS_HIDDEN_(already_AddRefed<nsStyleContext>)
- FindChildWithRules(const nsIAtom* aPseudoTag, nsRuleNode* aRules);
-
- NS_HIDDEN_(PRBool) Equals(const nsStyleContext* aOther) const;
- PRBool HasTextDecorations() { return mBits & NS_STYLE_HAS_TEXT_DECORATIONS; };
-
- NS_HIDDEN_(void) GetBorderPaddingFor(nsStyleBorderPadding& aBorderPadding);
-
- NS_HIDDEN_(void) SetStyle(nsStyleStructID aSID, nsStyleStruct* aStruct);
-
- nsRuleNode* GetRuleNode() { return mRuleNode; }
- void AddStyleBit(const PRUint32& aBit) { mBits |= aBit; }
-
- /*
- * Mark this style context's rule node (and its ancestors) to prevent
- * it from being garbage collected.
- */
- NS_HIDDEN_(void) Mark();
-
- /*
- * Get the style data for a style struct. This is the most important
- * member function of nsIStyleContext. It fills in a const pointer
- * to a style data struct that is appropriate for the style context's
- * frame. This struct may be shared with other contexts (either in
- * the rule tree or the style context tree), so it should not be
- * modified.
- *
- * This function will NOT return null (even when out of memory) when
- * given a valid style struct ID, so the result does not need to be
- * null-checked.
- *
- * The typesafe functions below are preferred to the use of this
- * function.
- *
- * See also |nsIFrame::GetStyleData| and the other global
- * |GetStyleData| in nsIFrame.h.
- */
- NS_HIDDEN_(const nsStyleStruct*) NS_FASTCALL GetStyleData(nsStyleStructID aSID);
-
- /**
- * Define typesafe getter functions for each style struct by
- * preprocessing the list of style structs. These functions are the
- * preferred way to get style data. The macro creates functions like:
- * const nsStyleBorder* GetStyleBorder();
- * const nsStyleColor* GetStyleColor();
- */
-
- #define STYLE_STRUCT(name_, checkdata_cb_, ctor_args_) \
- const nsStyle##name_ * GetStyle##name_() { \
- return NS_STATIC_CAST(const nsStyle##name_*, \
- GetStyleData(eStyleStruct_##name_)); \
- }
- #include "nsStyleStructList.h"
- #undef STYLE_STRUCT
-
-
- NS_HIDDEN_(const nsStyleStruct*) PeekStyleData(nsStyleStructID aSID);
-
- NS_HIDDEN_(nsStyleStruct*) GetUniqueStyleData(const nsStyleStructID& aSID);
-
- NS_HIDDEN_(void) ClearStyleData(nsPresContext* aPresContext);
-
- NS_HIDDEN_(nsChangeHint) CalcStyleDifference(nsStyleContext* aOther);
-
- #ifdef DEBUG
- NS_HIDDEN_(void) DumpRegressionData(nsPresContext* aPresContext, FILE* out,
- PRInt32 aIndent);
-
- NS_HIDDEN_(void) List(FILE* out, PRInt32 aIndent);
- #endif
-
- protected:
- NS_HIDDEN_(void) AppendChild(nsStyleContext* aChild);
- NS_HIDDEN_(void) RemoveChild(nsStyleContext* aChild);
-
- NS_HIDDEN_(void) ApplyStyleFixups(nsPresContext* aPresContext);
-
- nsStyleContext* mParent;
-
- // children are maintained in two circular doubly-linked lists,
- // mEmptyChild for children whose rule node is the root rule node, and
- // mChild for other children. The order of children is not
- // meaningful.
- nsStyleContext* mChild;
- nsStyleContext* mEmptyChild;
- nsStyleContext* mPrevSibling;
- nsStyleContext* mNextSibling;
-
- // If this style context is for a pseudo-element, the pseudo-element
- // atom. Otherwise, null.
- nsCOMPtr<nsIAtom> mPseudoTag;
-
- // The rule node is the node in the lexicographic tree of rule nodes
- // (the "rule tree") that indicates which style rules are used to
- // compute the style data, and in what cascading order. The least
- // specific rule matched is the one whose rule node is a child of the
- // root of the rule tree, and the most specific rule matched is the
- // |mRule| member of |mRuleNode|.
- nsRuleNode* const mRuleNode;
-
- // |mCachedStyleData| points to both structs that are owned by this
- // style context and structs that are owned by one of this style
- // context's ancestors (which are indirectly owned since this style
- // context owns a reference to its parent). If the bit in |mBits| is
- // set for a struct, that means that the pointer for that struct is
- // owned by an ancestor rather than by this style context.
- nsCachedStyleData mCachedStyleData; // Our cached style data.
- PRUint32 mBits; // Which structs are inherited from the
- // parent context.
- PRUint32 mRefCnt;
- };
-
- NS_HIDDEN_(already_AddRefed<nsStyleContext>)
- NS_NewStyleContext(nsStyleContext* aParentContext,
- nsIAtom* aPseudoTag,
- nsRuleNode* aRuleNode,
- nsPresContext* aPresContext);
- #endif
-