1/*	$NetBSD: mutex.h,v 1.1.1.1 2009/12/13 16:54:31 kardel Exp $	*/
2
3/*
4 * Copyright (C) 2004, 2007  Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 2000, 2001  Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20/* Id: mutex.h,v 1.6 2007/06/19 23:47:18 tbox Exp */
21
22#ifndef ISC_MUTEX_H
23#define ISC_MUTEX_H 1
24
25#include <isc/result.h>		/* for ISC_R_ codes */
26
27typedef int isc_mutex_t;
28
29#define isc_mutex_init(mp) \
30	(*(mp) = 0, ISC_R_SUCCESS)
31#define isc_mutex_lock(mp) \
32	((*(mp))++ == 0 ? ISC_R_SUCCESS : ISC_R_UNEXPECTED)
33#define isc_mutex_unlock(mp) \
34	(--(*(mp)) == 0 ? ISC_R_SUCCESS : ISC_R_UNEXPECTED)
35#define isc_mutex_trylock(mp) \
36	(*(mp) == 0 ? ((*(mp))++, ISC_R_SUCCESS) : ISC_R_LOCKBUSY)
37#define isc_mutex_destroy(mp) \
38	(*(mp) == 0 ? (*(mp) = -1, ISC_R_SUCCESS) : ISC_R_UNEXPECTED)
39#define isc_mutex_stats(fp)
40
41#endif /* ISC_MUTEX_H */
42