1/* Test for sem_post race: bug 14532.
2 Copyright (C) 2012-2024 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 <pthread.h>
20#include <semaphore.h>
21#include <stdio.h>
22
23#define NTHREADS 10
24#define NITER 100000
25
26sem_t sem;
27int c;
28volatile int thread_fail;
29
30static void *
31tf (void *arg)
32{
33 for (int i = 0; i < NITER; i++)
34 {
35 if (sem_wait (sem: &sem) != 0)
36 {
37 perror ("sem_wait");
38 thread_fail = 1;
39 }
40 ++c;
41 if (sem_post (sem: &sem) != 0)
42 {
43 perror ("sem_post");
44 thread_fail = 1;
45 }
46 }
47 return NULL;
48}
49
50static int
51do_test (void)
52{
53 if (sem_init (sem: &sem, pshared: 0, value: 0) != 0)
54 {
55 perror ("sem_init");
56 return 1;
57 }
58
59 pthread_t th[NTHREADS];
60 for (int i = 0; i < NTHREADS; i++)
61 {
62 if (pthread_create (newthread: &th[i], NULL, start_routine: tf, NULL) != 0)
63 {
64 puts (s: "pthread_create failed");
65 return 1;
66 }
67 }
68
69 if (sem_post (sem: &sem) != 0)
70 {
71 perror ("sem_post");
72 return 1;
73 }
74
75 for (int i = 0; i < NTHREADS; i++)
76 if (pthread_join (th: th[i], NULL) != 0)
77 {
78 puts (s: "pthread_join failed");
79 return 1;
80 }
81
82 if (c != NTHREADS * NITER)
83 {
84 printf (format: "c = %d, should be %d\n", c, NTHREADS * NITER);
85 return 1;
86 }
87 return thread_fail;
88}
89
90#define TEST_FUNCTION do_test ()
91#include "../test-skeleton.c"
92

source code of glibc/sysdeps/pthread/tst-sem14.c