1 | /* C11 threads trylock mutex 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 <stdio.h> |
21 | #include <unistd.h> |
22 | |
23 | #include <support/check.h> |
24 | |
25 | /* Shared mutex between child and parent. */ |
26 | static mtx_t mutex; |
27 | |
28 | /* Shared counter to check possible race conditions. */ |
29 | static char shrd_counter; |
30 | |
31 | /* Function to choose an action to do, depending on mtx_trylock |
32 | return value. */ |
33 | static inline void |
34 | choose_action (int action, char* thread_name) |
35 | { |
36 | switch (action) |
37 | { |
38 | case thrd_success: |
39 | ++shrd_counter; |
40 | |
41 | if (mtx_unlock (mutex: &mutex) != thrd_success) |
42 | FAIL_EXIT1 ("mtx_unlock failed" ); |
43 | break; |
44 | |
45 | case thrd_busy: |
46 | break; |
47 | |
48 | case thrd_error: |
49 | FAIL_EXIT1 ("%s lock error" , thread_name); |
50 | break; |
51 | } |
52 | } |
53 | |
54 | static int |
55 | child_add (void *arg) |
56 | { |
57 | char child_name[] = "child" ; |
58 | |
59 | /* Try to lock mutex. */ |
60 | choose_action (action: mtx_trylock (mutex: &mutex), thread_name: child_name); |
61 | |
62 | thrd_exit (res: thrd_success); |
63 | } |
64 | |
65 | static int |
66 | do_test (void) |
67 | { |
68 | thrd_t id; |
69 | char parent_name[] = "parent" ; |
70 | |
71 | if (mtx_init (mutex: &mutex, type: mtx_timed) != thrd_success) |
72 | FAIL_EXIT1 ("mtx_init failed" ); |
73 | |
74 | if (thrd_create (thr: &id, func: child_add, NULL) != thrd_success) |
75 | FAIL_EXIT1 ("thrd_create failed" ); |
76 | |
77 | choose_action (action: mtx_trylock (mutex: &mutex), thread_name: parent_name); |
78 | |
79 | if (thrd_join (thr: id, NULL) != thrd_success) |
80 | FAIL_EXIT1 ("thrd_join failed" ); |
81 | |
82 | if (shrd_counter != 2 && shrd_counter != 1) |
83 | FAIL_EXIT1 ("shrd_counter != {1,2} (%d)" , shrd_counter); |
84 | |
85 | mtx_destroy (mutex: &mutex); |
86 | |
87 | return 0; |
88 | } |
89 | |
90 | #include <support/test-driver.c> |
91 | |