1 /* Test for clock_adjtime
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 <stdlib.h>
21 #include <sys/time.h>
22 #include <support/check.h>
23 #include <support/timespec.h>
24 
25 #ifndef ADJTIME_CALL
26 # define ADJTIME_CALL(__clock, __timex) clock_adjtime (__clock, __timex)
27 #endif
28 
29 static int
do_test(void)30 do_test (void)
31 {
32   struct timespec tv_then, tv_now;
33   struct timex delta;
34 
35   /* Check if altering target time is allowed.  */
36   if (getenv (SETTIME_ENV_NAME) == NULL)
37     FAIL_UNSUPPORTED ("clock_adjtime is executed only when "\
38                       SETTIME_ENV_NAME" is set\n");
39 
40   tv_then = xclock_now (CLOCK_REALTIME);
41 
42   /* Setup time value to adjust - 1 sec. */
43   delta.time.tv_sec = 1;
44   delta.time.tv_usec = 0;
45   delta.modes = ADJ_SETOFFSET;
46 
47   int ret = ADJTIME_CALL (CLOCK_REALTIME, &delta);
48   if (ret == -1)
49     FAIL_EXIT1 ("clock_adjtime failed: %m\n");
50 
51   tv_now = xclock_now (CLOCK_REALTIME);
52 
53   /* Check if clock_adjtime adjusted the system time.  */
54   struct timespec r = timespec_sub (tv_now, tv_then);
55   TEST_COMPARE (support_timespec_check_in_range
56                 ((struct timespec) { 1, 0 }, r, 0.9, 1.1), 1);
57 
58   return 0;
59 }
60 
61 #include <support/test-driver.c>
62