content/smil/nsSMILTargetIdentifier.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is the Mozilla SMIL module.
  16  *
  17  * The Initial Developer of the Original Code is the Mozilla Corporation.
  18  * Portions created by the Initial Developer are Copyright (C) 2010
  19  * the Initial Developer. All Rights Reserved.
  20  *
  21  * Contributor(s):
  22  *   Daniel Holbert <dholbert@mozilla.com>
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
  26  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
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  33  * the provisions above, a recipient may use your version of this file under
  34  * the terms of any one of the MPL, the GPL or the LGPL.
  35  *
  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #ifndef NS_SMILTARGETIDENTIFIER_H_
  39 #define NS_SMILTARGETIDENTIFIER_H_
  40
  41 #include "mozilla/dom/Element.h"
  42 #include "nsAutoPtr.h"
  43 #include "prtypes.h"
  44
  45 /**
  46  * Struct: nsSMILTargetIdentifier
  47  *
  48  * Tuple of: { Animated Element, Attribute Name, Attribute Type (CSS vs. XML) }
  49  *
  50  * Used in nsSMILAnimationController as hash key for mapping an animation
  51  * target to the nsSMILCompositor for that target.
  52  *
  53  * NOTE: Need a nsRefPtr for the element & attribute name, because
  54  * nsSMILAnimationController retain its hash table for one sample into the
  55  * future, and we need to make sure their target isn't deleted in that time.
  56  */
  57
  58 struct nsSMILTargetIdentifier
  59 {
  60   nsSMILTargetIdentifier()
  61     : mElement(nsnull), mAttributeName(nsnull),
  62       mAttributeNamespaceID(kNameSpaceID_Unknown), mIsCSS(PR_FALSE) {}
  63
  64   inline PRBool Equals(const nsSMILTargetIdentifier& aOther) const
  65   {
  66     return (aOther.mElement              == mElement &&
  67             aOther.mAttributeName        == mAttributeName &&
  68             aOther.mAttributeNamespaceID == mAttributeNamespaceID &&
  69             aOther.mIsCSS                == mIsCSS);
  70   }
  71
  72   nsRefPtr<mozilla::dom::Element> mElement;
  73   nsRefPtr<nsIAtom>    mAttributeName;
  74   PRInt32              mAttributeNamespaceID;
  75   PRPackedBool         mIsCSS;
  76 };
  77
  78 /**
  79  * Class: nsSMILWeakTargetIdentifier
  80  *
  81  * Version of the above struct that uses non-owning pointers.  These are kept
  82  * private, to ensure that they aren't ever dereferenced (or used at all,
  83  * outside of Equals()).
  84  *
  85  * This is solely for comparisons to determine if a target has changed
  86  * from one sample to the next.
  87  */
  88 class nsSMILWeakTargetIdentifier
  89 {
  90 public:
  91   // Trivial constructor
  92   nsSMILWeakTargetIdentifier()
  93     : mElement(nsnull), mAttributeName(nsnull), mIsCSS(PR_FALSE) {}
  94
  95   // Allow us to update a weak identifier to match a given non-weak identifier
  96   nsSMILWeakTargetIdentifier&
  97     operator=(const nsSMILTargetIdentifier& aOther)
  98   {
  99     mElement = aOther.mElement;
 100     mAttributeName = aOther.mAttributeName;
 101     mIsCSS = aOther.mIsCSS;
 102     return *this;
 103   }
 104
 105   // Allow for comparison vs. non-weak identifier
 106   inline PRBool Equals(const nsSMILTargetIdentifier& aOther) const
 107   {
 108     return (aOther.mElement       == mElement &&
 109             aOther.mAttributeName == mAttributeName &&
 110             aOther.mIsCSS         == mIsCSS);
 111   }
 112
 113 private:
 114   const nsIContent* mElement;
 115   const nsIAtom*    mAttributeName;
 116   PRPackedBool      mIsCSS;
 117 };
 118
 119 #endif // NS_SMILTARGETIDENTIFIER_H_