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/* Copied from the Linux manpage
* with the printed times rounded to
* seconds for reproducibility.
* And some errors added.
*/
#include <err.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/timerfd.h>
#include <time.h>
#include <unistd.h>
#include <math.h>
#include <errno.h>
#include <assert.h>
#include "../../memcheck.h"
static void
print_elapsed_time(void)
{
int secs, nsecs;
static int first_call = 1;
struct timespec curr;
static struct timespec start;
int round_secs;
if (first_call) {
first_call = 0;
if (clock_gettime(CLOCK_MONOTONIC, &start) == -1)
err(EXIT_FAILURE, "clock_gettime");
}
if (clock_gettime(CLOCK_MONOTONIC, &curr) == -1)
err(EXIT_FAILURE, "clock_gettime");
secs = curr.tv_sec - start.tv_sec;
nsecs = curr.tv_nsec - start.tv_nsec;
if (nsecs < 0) {
secs--;
nsecs += 1000000000;
}
round_secs = round((secs*1e9 + nsecs)/1e9);
printf("%d: ", round_secs);
}
int
main(int argc, char *argv[])
{
int fd;
ssize_t s;
uint64_t exp, tot_exp, max_exp;
struct timespec now;
struct itimerspec new_value;
if (argc != 2 && argc != 4) {
fprintf(stderr, "%s init-secs [interval-secs max-exp]\n",
argv[0]);
exit(EXIT_FAILURE);
}
if (clock_gettime(CLOCK_REALTIME, &now) == -1)
err(EXIT_FAILURE, "clock_gettime");
/* Create a CLOCK_REALTIME absolute timer with initial
expiration and interval as specified in command line. */
new_value.it_value.tv_sec = now.tv_sec + atoi(argv[1]);
new_value.it_value.tv_nsec = now.tv_nsec;
if (argc == 2) {
new_value.it_interval.tv_sec = 0;
max_exp = 1;
} else {
new_value.it_interval.tv_sec = atoi(argv[2]);
max_exp = atoi(argv[3]);
}
new_value.it_interval.tv_nsec = 0;
fd = timerfd_create(CLOCK_REALTIME, 0);
if (fd == -1)
err(EXIT_FAILURE, "timerfd_create");
if (timerfd_settime(fd, TFD_TIMER_ABSTIME, &new_value, NULL) == -1)
err(EXIT_FAILURE, "timerfd_settime");
print_elapsed_time();
printf("timer started\n");
for (tot_exp = 0; tot_exp < max_exp;) {
s = read(fd, &exp, sizeof(uint64_t));
if (s != sizeof(uint64_t))
err(EXIT_FAILURE, "read");
tot_exp += exp;
print_elapsed_time();
printf("read: %" PRIu64 "; total=%" PRIu64 "\n", exp, tot_exp);
}
close(fd);
{
int a = CLOCK_REALTIME;
int b = TFD_CLOEXEC;
int c = TFD_TIMER_ABSTIME;
VALGRIND_MAKE_MEM_UNDEFINED(&a, sizeof(a));
VALGRIND_MAKE_MEM_UNDEFINED(&b, sizeof(b));
VALGRIND_MAKE_MEM_UNDEFINED(&c, sizeof(c));
struct itimerspec * get_ts = malloc(sizeof(*get_ts) - 2);
struct itimerspec * set_ts = malloc(sizeof(*set_ts) - 2);
struct itimerspec ts;
int retval;
errno = 0;
/* uninit clockid and flag but should work */
int fd2 = timerfd_create(a, b);
assert(fd2 != -1);
assert(errno == 0);
/* bad flag should fail */
timerfd_create(CLOCK_REALTIME, 1000000);
/* bad clockid should fail */
timerfd_create(1000000, TFD_CLOEXEC);
/* memory too small for requested get */
timerfd_gettime(fd2, get_ts);
/* should succeed */
timerfd_gettime(fd2, &ts);
ts.it_interval.tv_nsec += 100000;
/* uninit flag */
timerfd_settime(fd2, c, &ts, NULL);
errno = 0;
ts.it_interval.tv_nsec += 100000;
/* memory too small for requested old value */
retval = timerfd_settime(fd2, TFD_TIMER_ABSTIME, &ts, set_ts);
assert(retval == 0);
assert(errno == 0);
VALGRIND_MAKE_MEM_UNDEFINED(&fd2, sizeof(fd2));
timerfd_gettime(fd2, &ts);
ts.it_interval.tv_nsec += 100000;
timerfd_settime(fd2, TFD_TIMER_ABSTIME, &ts, NULL);
free(get_ts);
free(set_ts);
}
exit(EXIT_SUCCESS);
}
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