1 /* Basic tests for timespec_getres.
2 Copyright (C) 2021-2022 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 <time.h>
20 #include <support/check.h>
21
22 static int
do_test(void)23 do_test (void)
24 {
25 {
26 struct timespec ts;
27 TEST_COMPARE (timespec_getres (&ts, 0), 0);
28 TEST_COMPARE (timespec_getres (NULL, 0), 0);
29 }
30
31 {
32 struct timespec ts;
33 TEST_COMPARE (timespec_getres (&ts, TIME_UTC), TIME_UTC);
34 /* Expect all supported systems to support TIME_UTC with
35 resolution better than one second. */
36 TEST_VERIFY (ts.tv_sec == 0);
37 TEST_VERIFY (ts.tv_nsec > 0);
38 TEST_VERIFY (ts.tv_nsec < 1000000000);
39 TEST_COMPARE (timespec_getres (NULL, TIME_UTC), TIME_UTC);
40 /* Expect the resolution to be the same as that reported for
41 CLOCK_REALTIME with clock_getres. */
42 struct timespec cts;
43 TEST_COMPARE (clock_getres (CLOCK_REALTIME, &cts), 0);
44 TEST_COMPARE (ts.tv_sec, cts.tv_sec);
45 TEST_COMPARE (ts.tv_nsec, cts.tv_nsec);
46 }
47
48 return 0;
49 }
50
51 #include <support/test-driver.c>
52