1/*
 2 * Copyright 2001-2005, Haiku.
 3 * Distributed under the terms of the MIT License.
 4 *
 5 * Authors:
 6 *		DarkWyrm <bpmagic@columbus.rr.com>
 7 *		Axel Dörfler, axeld@pinc-software.de
 8 */
 9#ifndef REFERENCE_COUNTING_H
10#define REFERENCE_COUNTING_H
11
12
13#include <SupportDefs.h>
14
15
16/*!
17	\class ReferenceCounting ReferenceCounting.h
18	\brief Base class for reference counting objects
19
20	ReferenceCounting objects track dependencies upon a particular object. In this way,
21	it is possible to ensure that a shared resource is not deleted if something else
22	needs it. How the dependency tracking is done largely depends on the child class.
23*/
24class ReferenceCounting {
25	public:
26		ReferenceCounting()
27			: fReferenceCount(1) {}
28		virtual ~ReferenceCounting() {}
29
30		inline void Acquire();
31		inline bool Release();
32
33	private:
34		int32 fReferenceCount;
35};
36
37
38inline void
39ReferenceCounting::Acquire()
40{
41	atomic_add(&fReferenceCount, 1);
42}
43
44inline bool
45ReferenceCounting::Release()
46{
47	if (atomic_add(&fReferenceCount, -1) == 1) {
48		delete this;
49		return true;
50	}
51
52	return false;
53}
54
55#endif	/* REFERENCE_COUNTING_H */