gecko-dev/xpcom/ds/nsIArena.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Netscape 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/NPL/
*
* 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):
*
* 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
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* use your version of this file under the terms of the NPL, indicate your
* decision by deleting the provisions above and replace them with the notice
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* the provisions above, a recipient may use your version of this file under
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* ***** END LICENSE BLOCK ***** */
#ifndef nsIArena_h___
#define nsIArena_h___
#include "nscore.h"
#include "nsISupports.h"
#define NS_MIN_ARENA_BLOCK_SIZE 64
#define NS_DEFAULT_ARENA_BLOCK_SIZE 4096
/// Interface IID for nsIArena
#define NS_IARENA_IID \
{ 0xa24fdad0, 0x93b4, 0x11d1, \
{0x89, 0x5b, 0x00, 0x60, 0x08, 0x91, 0x1b, 0x81} }
#define NS_ARENA_CONTRACTID "@mozilla.org/arena;1"
#define NS_ARENA_CLASSNAME "Arena"
/** Interface to a memory arena abstraction. Arena's use large blocks
* of memory to allocate smaller objects. Arena's provide no free
* operator; instead, all of the objects in the arena are deallocated
* by deallocating the arena (e.g. when it's reference count goes to
* zero)
*/
class nsIArena : public nsISupports {
public:
static const nsIID& GetIID() { static nsIID iid = NS_IARENA_IID; return iid; }
NS_IMETHOD Init(PRUint32 arenaBlockSize) = 0;
NS_IMETHOD_(void*) Alloc(PRUint32 size) = 0;
};
/**
* Create a new arena using the desired block size for allocating the
* underlying memory blocks. The underlying memory blocks are allocated
* using the PR heap.
*/
extern NS_COM nsresult NS_NewHeapArena(nsIArena** aInstancePtrResult,
PRUint32 aArenaBlockSize = 0);
#define NS_ARENA_CID \
{ /* 9832ec80-0d6b-11d3-9331-00104ba0fd40 */ \
0x9832ec80, \
0x0d6b, \
0x11d3, \
{0x93, 0x31, 0x00, 0x10, 0x4b, 0xa0, 0xfd, 0x40} \
}
#endif /* nsIArena_h___ */