RetroZilla/xpcom/base/nsISupportsBase.h
2015-10-20 23:03:22 -04:00

120 lines
3.9 KiB
C++

/* ***** 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 XPCOM.
*
* The Initial Developer of the Original Code is Netscape Communications Corp.
* Portions created by the Initial Developer are Copyright (C) 2001
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either 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 nsISupportsBase_h__
#define nsISupportsBase_h__
#ifndef nscore_h___
#include "nscore.h"
#endif
#ifndef nsID_h__
#include "nsID.h"
#endif
/*@{*/
/**
* IID for the nsISupports interface
* {00000000-0000-0000-c000-000000000046}
*
* To maintain binary compatibility with COM's IUnknown, we define the IID
* of nsISupports to be the same as that of COM's IUnknown.
*/
#define NS_ISUPPORTS_IID \
{ 0x00000000, 0x0000, 0x0000, \
{0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46} }
/**
* Reference count values
*
* This is the return type for AddRef() and Release() in nsISupports.
* IUnknown of COM returns an unsigned long from equivalent functions.
* The following ifdef exists to maintain binary compatibility with
* IUnknown.
*/
#if defined(XP_WIN) && PR_BYTES_PER_LONG == 4
typedef unsigned long nsrefcnt;
#else
typedef PRUint32 nsrefcnt;
#endif
/**
* Basic component object model interface. Objects which implement
* this interface support runtime interface discovery (QueryInterface)
* and a reference counted memory model (AddRef/Release). This is
* modelled after the win32 IUnknown API.
*/
class NS_NO_VTABLE nsISupports {
public:
/**
* @name Methods
*/
//@{
/**
* A run time mechanism for interface discovery.
* @param aIID [in] A requested interface IID
* @param aInstancePtr [out] A pointer to an interface pointer to
* receive the result.
* @return <b>NS_OK</b> if the interface is supported by the associated
* instance, <b>NS_NOINTERFACE</b> if it is not.
* <b>NS_ERROR_INVALID_POINTER</b> if <i>aInstancePtr</i> is <b>NULL</b>.
*/
NS_IMETHOD QueryInterface(REFNSIID aIID, void** aInstancePtr) = 0;
/**
* Increases the reference count for this interface.
* The associated instance will not be deleted unless
* the reference count is returned to zero.
*
* @return The resulting reference count.
*/
NS_IMETHOD_(nsrefcnt) AddRef(void) = 0;
/**
* Decreases the reference count for this interface.
* Generally, if the reference count returns to zero,
* the associated instance is deleted.
*
* @return The resulting reference count.
*/
NS_IMETHOD_(nsrefcnt) Release(void) = 0;
//@}
};
/*@}*/
#endif