1 /* C11 threads condition variable tests.
2 Copyright (C) 2018-2022 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 <stdio.h>
21 #include <unistd.h>
22
23 #include <support/check.h>
24
25 /* Shared condition variable between child and parent. */
26 static cnd_t cond;
27
28 /* Mutex needed to signal and wait threads. */
29 static mtx_t mutex;
30
31 static int
signal_parent(void)32 signal_parent (void)
33 {
34 /* Acquire the lock so that cnd_signal does not run until
35 cnd_timedwait has been called. */
36 if (mtx_lock (&mutex) != thrd_success)
37 FAIL_EXIT1 ("mtx_lock failed");
38 if (cnd_signal (&cond) != thrd_success)
39 FAIL_EXIT1 ("cnd_signal");
40 if (mtx_unlock (&mutex) != thrd_success)
41 FAIL_EXIT1 ("mtx_unlock");
42
43 thrd_exit (thrd_success);
44 }
45
46 static int
do_test(void)47 do_test (void)
48 {
49 thrd_t id;
50
51 if (cnd_init (&cond) != thrd_success)
52 FAIL_EXIT1 ("cnd_init failed");
53 if (mtx_init (&mutex, mtx_plain) != thrd_success)
54 FAIL_EXIT1 ("mtx_init failed");
55
56 if (mtx_lock (&mutex) != thrd_success)
57 FAIL_EXIT1 ("mtx_lock failed");
58
59 if (thrd_create (&id, (thrd_start_t) signal_parent, NULL)
60 != thrd_success)
61 FAIL_EXIT1 ("thrd_create failed");
62
63 if (cnd_wait (&cond, &mutex) != thrd_success)
64 FAIL_EXIT1 ("cnd_wait failed");
65
66 /* Joining is not mandatory here, but still done to assure child thread
67 ends correctly. */
68 if (thrd_join (id, NULL) != thrd_success)
69 FAIL_EXIT1 ("thrd_join failed");
70
71 if (mtx_unlock (&mutex) != thrd_success)
72 FAIL_EXIT1 ("mtx_unlock");
73
74 mtx_destroy (&mutex);
75 cnd_destroy (&cond);
76
77 return 0;
78 }
79
80 #include <support/test-driver.c>
81