1/* C11 threads mutex initialization implementation.
2 Copyright (C) 2018-2024 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#include <shlib-compat.h>
21
22#include "thrd_priv.h"
23
24int
25__mtx_init (mtx_t *mutex, int type)
26{
27 _Static_assert (sizeof (mtx_t) == sizeof (pthread_mutex_t),
28 "sizeof (mtx_t) != sizeof (pthread_mutex_t)");
29 _Static_assert (alignof (mtx_t) == alignof (pthread_mutex_t),
30 "alignof (mtx_t) != alignof (pthread_mutex_t)");
31
32 pthread_mutexattr_t attr;
33
34 __pthread_mutexattr_init (&attr);
35
36 /* Another possible solution would be to set the flags directly in
37 mutex object. */
38 switch (type)
39 {
40 case mtx_plain | mtx_recursive:
41 case mtx_timed | mtx_recursive:
42 __pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
43 break;
44 case mtx_plain:
45 case mtx_timed: /* No difference between both in standard */
46 default:
47 __pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_NORMAL);
48 break;
49 }
50
51 int err_code = __pthread_mutex_init ((pthread_mutex_t *) mutex, &attr);
52 /* pthread_mutexattr_destroy implementation is a noop. */
53 return thrd_err_map (err_code);
54}
55#if PTHREAD_IN_LIBC
56versioned_symbol (libc, __mtx_init, mtx_init, GLIBC_2_34);
57# if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_28, GLIBC_2_34)
58compat_symbol (libpthread, __mtx_init, mtx_init, GLIBC_2_28);
59# endif
60#else /* !PTHREAD_IN_LIBC */
61strong_alias (__mtx_init, mtx_init)
62#endif
63

source code of glibc/sysdeps/pthread/mtx_init.c