timer-stress.c
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Authored by tstarling on Apr 2 2025, 4:35 AM.

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Referenced Files

	F58963620: timer-stress.c
	Apr 2 2025, 4:50 AM

	F58963598: timer-stress.c
	Apr 2 2025, 4:35 AM

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	#include <signal.h>
	#include <time.h>
	#include <stdio.h>
	#include <unistd.h>
	#include <string.h>
	#include <stdlib.h>

	void on_good_timer(union sigval sv) {
	}

	void on_bad_timer(union sigval sv) {
	long t = time(NULL);
	long delta = t - (long)sv.sival_ptr;
	char message[100];
	snprintf(message, sizeof(message), "Timer expired after %ld seconds\n", delta);
	write(STDERR_FILENO, message, strlen(message));
	abort();
	}

	int main(int argc, char** argv) {
	timer_t id;
	struct itimerspec its_long = {.it_value = {.tv_sec = 180}};
	struct itimerspec its_short = {.it_value = {.tv_nsec = 1000}};
	struct itimerspec its_zero = {.it_interval = {.tv_sec = 0}};

	struct sigevent ev_short = {
	.sigev_notify = SIGEV_THREAD,
	.sigev_notify_function = on_good_timer,
	};

	struct sigevent ev_long = {
	.sigev_notify = SIGEV_THREAD,
	.sigev_notify_function = on_bad_timer,
	};

	for (int which = 0; ; which = !which) {
	struct sigevent * ev = which ? &ev_short : &ev_long;
	struct itimerspec * its = which ? &its_short : &its_long;

	ev->sigev_value.sival_ptr = (void*)time(NULL);
	if (timer_create(CLOCK_MONOTONIC, ev, &id)) {
	perror("timer_create");
	continue;
	}
	if (timer_settime(id, 0, its, NULL)) {
	perror("timer_settime(x)");
	goto cleanup;
	}
	if (timer_settime(id, 0, &its_zero, NULL)) {
	perror("timer_settime(0)");
	}
	cleanup:
	if (timer_delete(id)) {
	perror("timer_delete");
	}
	}
	}

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