1/* Support functionality for using time.
2 Copyright (C) 2019-2022 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#ifndef SUPPORT_TIME_H
20#define SUPPORT_TIME_H
21
22#include <time.h>
23
24__BEGIN_DECLS
25
26/* Name of the env variable, which indicates if it is possible to
27 adjust time on target machine. */
28#define SETTIME_ENV_NAME "GLIBC_TEST_ALLOW_TIME_SETTING"
29
30/* The following functions call the corresponding libc functions and
31 terminate the process on error. */
32
33#ifndef __USE_TIME_BITS64
34void xclock_gettime (clockid_t clock, struct timespec *ts);
35void xclock_settime (clockid_t clock, const struct timespec *ts);
36#else
37void __REDIRECT (xclock_gettime, (clockid_t clock, struct timespec *ts),
38 xclock_gettime_time64);
39void __REDIRECT (xclock_settime, (clockid_t clock, const struct timespec *ts),
40 xclock_settime_time64);
41#endif
42
43/* This helper can often simplify tests by avoiding an explicit
44 variable declaration or allowing that declaration to be const. */
45
46static inline struct timespec xclock_now (clockid_t clock)
47{
48 struct timespec ts;
49 xclock_gettime (clock, ts: &ts);
50 return ts;
51}
52
53__END_DECLS
54
55#endif /* SUPPORT_TIME_H */
56

source code of glibc/support/xtime.h