xpcom/base/nsISupportsBase.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6 // IWYU pragma: private, include "nsISupports.h"
   7
   8 #ifndef nsISupportsBase_h__
   9 #define nsISupportsBase_h__
  10
  11 #ifndef nscore_h___
  12 #include "nscore.h"
  13 #endif
  14
  15 #ifndef nsID_h__
  16 #include "nsID.h"
  17 #endif
  18
  19
  20 /*@{*/
  21 /**
  22  * IID for the nsISupports interface
  23  * {00000000-0000-0000-c000-000000000046}
  24  *
  25  * To maintain binary compatibility with COM's IUnknown, we define the IID
  26  * of nsISupports to be the same as that of COM's IUnknown.
  27  */
  28 #define NS_ISUPPORTS_IID                                                      \
  29   { 0x00000000, 0x0000, 0x0000,                                               \
  30     {0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46} }
  31
  32 /**
  33  * Basic component object model interface. Objects which implement
  34  * this interface support runtime interface discovery (QueryInterface)
  35  * and a reference counted memory model (AddRef/Release). This is
  36  * modelled after the win32 IUnknown API.
  37  */
  38 class NS_NO_VTABLE nsISupports
  39 {
  40 public:
  41
  42   NS_DECLARE_STATIC_IID_ACCESSOR(NS_ISUPPORTS_IID)
  43
  44   /**
  45    * @name Methods
  46    */
  47
  48   //@{
  49   /**
  50    * A run time mechanism for interface discovery.
  51    * @param aIID [in] A requested interface IID
  52    * @param aInstancePtr [out] A pointer to an interface pointer to
  53    * receive the result.
  54    * @return <b>NS_OK</b> if the interface is supported by the associated
  55    * instance, <b>NS_NOINTERFACE</b> if it is not.
  56    *
  57    * aInstancePtr must not be null.
  58    */
  59   NS_IMETHOD QueryInterface(REFNSIID aIID, void** aInstancePtr) = 0;
  60   /**
  61    * Increases the reference count for this interface.
  62    * The associated instance will not be deleted unless
  63    * the reference count is returned to zero.
  64    *
  65    * @return The resulting reference count.
  66    */
  67   NS_IMETHOD_(MozExternalRefCountType) AddRef(void) = 0;
  68
  69   /**
  70    * Decreases the reference count for this interface.
  71    * Generally, if the reference count returns to zero,
  72    * the associated instance is deleted.
  73    *
  74    * @return The resulting reference count.
  75    */
  76   NS_IMETHOD_(MozExternalRefCountType) Release(void) = 0;
  77
  78   //@}
  79 };
  80
  81 NS_DEFINE_STATIC_IID_ACCESSOR(nsISupports, NS_ISUPPORTS_IID)
  82
  83 /*@}*/
  84
  85 #endif