aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/htl/sem-destroy.c
blob: 0d5b6bd1d1c7794e3b40517d0640e802dd34163a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
/* Destroy a semaphore.  Generic version.
   Copyright (C) 2005-2022 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library;  if not, see
   <https://www.gnu.org/licenses/>.  */

#include <semaphore.h>
#include <errno.h>

#include <pt-internal.h>

int
__sem_destroy (sem_t *sem)
{
  struct new_sem *isem = (struct new_sem *) sem;
  if (
#if __HAVE_64B_ATOMICS
      atomic_load_relaxed (&isem->data) >> SEM_NWAITERS_SHIFT
#else
      atomic_load_relaxed (&isem->value) & SEM_NWAITERS_MASK
      || isem->nwaiters
#endif
      )
    /* There are threads waiting on *SEM.  */
    {
      errno = EBUSY;
      return -1;
    }

  return 0;
}

strong_alias (__sem_destroy, sem_destroy);