From 92f7b465101c23e45f66c6ad25ba243df49556a0 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Wed, 16 Jun 2021 13:44:03 -0300 Subject: support: Add support_create_timer It is a simple wrapper over timer_create, timer_settime, and sigaction. It will be used to check for large timeout to trigger an EINTR and to avoid use a large timeout (as for alarm()). Reviewed-by: Lukasz Majewski --- support/support_create_timer.c | 69 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 support/support_create_timer.c (limited to 'support/support_create_timer.c') diff --git a/support/support_create_timer.c b/support/support_create_timer.c new file mode 100644 index 0000000000..c93aaa5c6b --- /dev/null +++ b/support/support_create_timer.c @@ -0,0 +1,69 @@ +/* Create a periodic timer. + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +static void +dummy_alrm_handler (int sig) +{ +} + +timer_t +support_create_timer (uint64_t sec, long int nsec, bool repeat, + void (*callback)(int)) +{ + struct sigaction sa; + sa.sa_handler = callback != NULL ? callback : dummy_alrm_handler; + sigemptyset (&sa.sa_mask); + sa.sa_flags = 0; + xsigaction (SIGALRM, &sa, NULL); + + struct sigevent ev = { + .sigev_notify = SIGEV_SIGNAL, + .sigev_signo = SIGALRM + }; + timer_t timerid; + int r = timer_create (CLOCK_REALTIME, &ev, &timerid); + if (r == -1) + FAIL_EXIT1 ("timer_create: %m"); + + /* Single timer with 0.1s. */ + struct itimerspec its = + { + { .tv_sec = repeat ? sec : 0, .tv_nsec = repeat ? nsec : 0 }, + { .tv_sec = sec, .tv_nsec = nsec } + }; + r = timer_settime (timerid, 0, &its, NULL); + if (r == -1) + FAIL_EXIT1 ("timer_settime: %m"); + + return timerid; +} + +/* Disable the timer TIMER. */ +void +support_delete_timer (timer_t timer) +{ + int r = timer_delete (timer); + if (r == -1) + FAIL_EXIT1 ("timer_delete: %m"); + xsignal (SIGALRM, SIG_DFL); +} -- cgit v1.2.3-70-g09d2