xref: /freebsd/lib/libstdthreads/mtx.c (revision 3f0efe05432b1633991114ca4ca330102a561959)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 Ed Schouten <ed@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #include <errno.h>
31 #include <pthread.h>
32 
33 #include "threads.h"
34 
35 void
36 mtx_destroy(mtx_t *mtx)
37 {
38 
39 	(void)pthread_mutex_destroy(mtx);
40 }
41 
42 int
43 mtx_init(mtx_t *mtx, int type)
44 {
45 	pthread_mutexattr_t attr;
46 	int mt, res;
47 
48 	switch (type) {
49 	case mtx_plain:
50 	case mtx_timed:
51 		mt = PTHREAD_MUTEX_NORMAL;
52 		break;
53 	case mtx_plain | mtx_recursive:
54 	case mtx_timed | mtx_recursive:
55 		mt = PTHREAD_MUTEX_RECURSIVE;
56 		break;
57 	default:
58 		return (thrd_error);
59 	}
60 
61 	if (pthread_mutexattr_init(&attr) != 0)
62 		return (thrd_error);
63 	res = thrd_success;
64 	if (pthread_mutexattr_settype(&attr, mt) != 0 ||
65 	    pthread_mutex_init(mtx, &attr) != 0)
66 		res = thrd_error;
67 	pthread_mutexattr_destroy(&attr);
68 	return (res);
69 }
70 
71 int
72 mtx_lock(mtx_t *mtx)
73 {
74 
75 	if (pthread_mutex_lock(mtx) != 0)
76 		return (thrd_error);
77 	return (thrd_success);
78 }
79 
80 int
81 mtx_timedlock(mtx_t *restrict mtx, const struct timespec *restrict ts)
82 {
83 
84 	switch (pthread_mutex_timedlock(mtx, ts)) {
85 	case 0:
86 		return (thrd_success);
87 	case ETIMEDOUT:
88 		return (thrd_timedout);
89 	default:
90 		return (thrd_error);
91 	}
92 }
93 
94 int
95 mtx_trylock(mtx_t *mtx)
96 {
97 
98 	switch (pthread_mutex_trylock(mtx)) {
99 	case 0:
100 		return (thrd_success);
101 	case EBUSY:
102 		return (thrd_busy);
103 	default:
104 		return (thrd_error);
105 	}
106 }
107 
108 int
109 mtx_unlock(mtx_t *mtx)
110 {
111 
112 	if (pthread_mutex_unlock(mtx) != 0)
113 		return (thrd_error);
114 	return (thrd_success);
115 }
116