xpcom/base/nsISupportsBase.h

   1 /* ***** BEGIN LICENSE BLOCK *****
   2  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   3  *
   4  * The contents of this file are subject to the Mozilla Public License Version
   5  * 1.1 (the "License"); you may not use this file except in compliance with
   6  * the License. You may obtain a copy of the License at
   7  * http://www.mozilla.org/MPL/
   8  *
   9  * Software distributed under the License is distributed on an "AS IS" basis,
  10  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  11  * for the specific language governing rights and limitations under the
  12  * License.
  13  *
  14  * The Original Code is XPCOM.
  15  *
  16  * The Initial Developer of the Original Code is Netscape Communications Corp.
  17  * Portions created by the Initial Developer are Copyright (C) 2001
  18  * the Initial Developer. All Rights Reserved.
  19  *
  20  * Contributor(s):
  21  *
  22  * Alternatively, the contents of this file may be used under the terms of
  23  * either the GNU General Public License Version 2 or later (the "GPL"), or
  24  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  25  * in which case the provisions of the GPL or the LGPL are applicable instead
  26  * of those above. If you wish to allow use of your version of this file only
  27  * under the terms of either the GPL or the LGPL, and not to allow others to
  28  * use your version of this file under the terms of the MPL, indicate your
  29  * decision by deleting the provisions above and replace them with the notice
  30  * and other provisions required by the GPL or the LGPL. If you do not delete
  31  * the provisions above, a recipient may use your version of this file under
  32  * the terms of any one of the MPL, the GPL or the LGPL.
  33  *
  34  * ***** END LICENSE BLOCK ***** */
  35
  36 #ifndef nsISupportsBase_h__
  37 #define nsISupportsBase_h__
  38
  39 #ifndef nscore_h___
  40 #include "nscore.h"
  41 #endif
  42
  43 #ifndef nsID_h__
  44 #include "nsID.h"
  45 #endif
  46
  47
  48 /*@{*/
  49 /**
  50  * IID for the nsISupports interface
  51  * {00000000-0000-0000-c000-000000000046}
  52  *
  53  * To maintain binary compatibility with COM's IUnknown, we define the IID
  54  * of nsISupports to be the same as that of COM's IUnknown.
  55  */
  56 #define NS_ISUPPORTS_IID                                                      \
  57   { 0x00000000, 0x0000, 0x0000,                                               \
  58     {0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46} }
  59
  60 /**
  61  * Basic component object model interface. Objects which implement
  62  * this interface support runtime interface discovery (QueryInterface)
  63  * and a reference counted memory model (AddRef/Release). This is
  64  * modelled after the win32 IUnknown API.
  65  */
  66 class NS_NO_VTABLE nsISupports {
  67 public:
  68
  69   NS_DECLARE_STATIC_IID_ACCESSOR(NS_ISUPPORTS_IID)
  70
  71   /**
  72    * @name Methods
  73    */
  74
  75   //@{
  76   /**
  77    * A run time mechanism for interface discovery.
  78    * @param aIID [in] A requested interface IID
  79    * @param aInstancePtr [out] A pointer to an interface pointer to
  80    * receive the result.
  81    * @return <b>NS_OK</b> if the interface is supported by the associated
  82    * instance, <b>NS_NOINTERFACE</b> if it is not.
  83    *
  84    * aInstancePtr must not be null.
  85    */
  86   NS_IMETHOD QueryInterface(REFNSIID aIID, void** aInstancePtr) = 0;
  87   /**
  88    * Increases the reference count for this interface.
  89    * The associated instance will not be deleted unless
  90    * the reference count is returned to zero.
  91    *
  92    * @return The resulting reference count.
  93    */
  94   NS_IMETHOD_(nsrefcnt) AddRef(void) = 0;
  95
  96   /**
  97    * Decreases the reference count for this interface.
  98    * Generally, if the reference count returns to zero,
  99    * the associated instance is deleted.
 100    *
 101    * @return The resulting reference count.
 102    */
 103   NS_IMETHOD_(nsrefcnt) Release(void) = 0;
 104
 105   //@}
 106 };
 107
 108 NS_DEFINE_STATIC_IID_ACCESSOR(nsISupports, NS_ISUPPORTS_IID)
 109
 110 /*@}*/
 111
 112 #endif