1 /* Create a periodic timer.
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 <support/check.h>
20 #include <support/support.h>
21 #include <support/xsignal.h>
22 #include <time.h>
23
24 static void
dummy_alrm_handler(int sig)25 dummy_alrm_handler (int sig)
26 {
27 }
28
29 timer_t
support_create_timer(uint64_t sec,long int nsec,bool repeat,void (* callback)(int))30 support_create_timer (uint64_t sec, long int nsec, bool repeat,
31 void (*callback)(int))
32 {
33 struct sigaction sa;
34 sa.sa_handler = callback != NULL ? callback : dummy_alrm_handler;
35 sigemptyset (&sa.sa_mask);
36 sa.sa_flags = 0;
37 xsigaction (SIGALRM, &sa, NULL);
38
39 struct sigevent ev = {
40 .sigev_notify = SIGEV_SIGNAL,
41 .sigev_signo = SIGALRM
42 };
43 timer_t timerid;
44 int r = timer_create (CLOCK_REALTIME, &ev, &timerid);
45 if (r == -1)
46 FAIL_EXIT1 ("timer_create: %m");
47
48 /* Single timer with 0.1s. */
49 struct itimerspec its =
50 {
51 { .tv_sec = repeat ? sec : 0, .tv_nsec = repeat ? nsec : 0 },
52 { .tv_sec = sec, .tv_nsec = nsec }
53 };
54 r = timer_settime (timerid, 0, &its, NULL);
55 if (r == -1)
56 FAIL_EXIT1 ("timer_settime: %m");
57
58 return timerid;
59 }
60
61 /* Disable the timer TIMER. */
62 void
support_delete_timer(timer_t timer)63 support_delete_timer (timer_t timer)
64 {
65 int r = timer_delete (timer);
66 if (r == -1)
67 FAIL_EXIT1 ("timer_delete: %m");
68 xsignal (SIGALRM, SIG_DFL);
69 }
70