1/* C11 threads mutex initialization implementation.
2 Copyright (C) 2018-2021 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <stdalign.h>
20
21#include "thrd_priv.h"
22
23int
24mtx_init (mtx_t *mutex, int type)
25{
26 _Static_assert (sizeof (mtx_t) == sizeof (pthread_mutex_t),
27 "sizeof (mtx_t) != sizeof (pthread_mutex_t)");
28 _Static_assert (alignof (mtx_t) == alignof (pthread_mutex_t),
29 "alignof (mtx_t) != alignof (pthread_mutex_t)");
30
31 pthread_mutexattr_t attr;
32
33 __pthread_mutexattr_init (&attr);
34
35 /* Another possible solution would be to set the flags directly in
36 mutex object. */
37 switch (type)
38 {
39 case mtx_plain | mtx_recursive:
40 case mtx_timed | mtx_recursive:
41 __pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
42 break;
43 case mtx_plain:
44 case mtx_timed: /* No difference between both in standard */
45 default:
46 __pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_NORMAL);
47 break;
48 }
49
50 int err_code = __pthread_mutex_init ((pthread_mutex_t *) mutex, &attr);
51 /* pthread_mutexattr_destroy implementation is a noop. */
52 return thrd_err_map (err_code);
53}
54