1/*
2	Copyright 1999-2001, Be Incorporated.   All Rights Reserved.
3	This file may be used under the terms of the Be Sample Code License.
4*/
5
6#ifndef _LOCK_H
7#define _LOCK_H
8
9#include <BeBuild.h>
10
11#include <OS.h>
12
13#ifndef _IMPEXP_KERNEL
14#define _IMPEXP_KERNEL
15#endif
16
17#ifdef __cplusplus
18	extern "C" {
19#else
20	typedef struct lock lock;
21	typedef struct mlock mlock;
22#endif
23
24
25struct lock {
26	sem_id		s;
27	long		c;
28};
29
30struct mlock {
31	sem_id		s;
32};
33
34extern _IMPEXP_KERNEL int	new_lock(lock *l, const char *name);
35extern _IMPEXP_KERNEL int	free_lock(lock *l);
36
37#ifdef LOCK
38#undef LOCK
39#endif
40
41#define	LOCK(l)		if (atomic_add(&l.c, -1) <= 0) acquire_sem(l.s);
42#define	UNLOCK(l)	if (atomic_add(&l.c, 1) < 0) release_sem(l.s);
43
44extern _IMPEXP_KERNEL int	new_mlock(mlock *l, long c, const char *name);
45extern _IMPEXP_KERNEL int	free_mlock(mlock *l);
46
47#define		LOCKM(l,cnt)	acquire_sem_etc(l.s, cnt, 0, 0)
48#define		UNLOCKM(l,cnt)	release_sem_etc(l.s, cnt, 0)
49
50
51#ifdef __cplusplus
52  } // extern "C"
53#endif
54
55#endif
56