1/* C11 threads condition broadcast variable tests.
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 <threads.h>
20#include <stdbool.h>
21#include <stdio.h>
22#include <unistd.h>
23
24#include <support/check.h>
25
26/* Condition variable where child threads will wait. */
27static cnd_t cond;
28
29/* Mutex to control wait on cond. */
30static mtx_t mutex;
31
32/* Number of threads which have entered the cnd_wait region. */
33static unsigned int waiting_threads;
34
35/* Code executed by each thread. */
36static int
37child_wait (void* data)
38{
39 /* Wait until parent thread sends broadcast here. */
40 mtx_lock (mutex: &mutex);
41 ++waiting_threads;
42 cnd_wait (cond: &cond, mutex: &mutex);
43 mtx_unlock (mutex: &mutex);
44
45 thrd_exit (res: thrd_success);
46}
47
48#define N 5
49
50static int
51do_test (void)
52{
53 thrd_t ids[N];
54 unsigned char i;
55
56 if (cnd_init (cond: &cond) != thrd_success)
57 FAIL_EXIT1 ("cnd_init failed");
58 if (mtx_init (mutex: &mutex, type: mtx_plain) != thrd_success)
59 FAIL_EXIT1 ("mtx_init failed");
60
61 /* Create N new threads. */
62 for (i = 0; i < N; ++i)
63 {
64 if (thrd_create (thr: &ids[i], func: child_wait, NULL) != thrd_success)
65 FAIL_EXIT1 ("thrd_create failed");
66 }
67
68 /* Wait for other threads to reach their wait func. */
69 while (true)
70 {
71 mtx_lock (mutex: &mutex);
72 TEST_VERIFY (waiting_threads <= N);
73 bool done_waiting = waiting_threads == N;
74 mtx_unlock (mutex: &mutex);
75 if (done_waiting)
76 break;
77 thrd_sleep (time_point: &((struct timespec){.tv_nsec = 100 * 1000 * 1000}), NULL);
78 }
79
80 mtx_lock (mutex: &mutex);
81 if (cnd_broadcast (cond: &cond) != thrd_success)
82 FAIL_EXIT1 ("cnd_broadcast failed");
83 mtx_unlock (mutex: &mutex);
84
85 for (i = 0; i < N; ++i)
86 {
87 if (thrd_join (thr: ids[i], NULL) != thrd_success)
88 FAIL_EXIT1 ("thrd_join failed");
89 }
90
91 mtx_destroy (mutex: &mutex);
92 cnd_destroy (COND: &cond);
93
94 return 0;
95}
96
97#include <support/test-driver.c>
98

source code of glibc/sysdeps/pthread/tst-cnd-broadcast.c