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/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* libuvcgadget timer utils
*
* Copyright (C) 2022 Daniel Scally
*
* Contact: Daniel Scally <dan.scally@ideasonboard.com>
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/timerfd.h>
#include <unistd.h>
#include "timer.h"
struct timer {
int fd;
struct itimerspec settings;
};
struct timer *timer_new(void)
{
struct timer *timer;
timer = malloc(sizeof(*timer));
if (!timer)
return NULL;
memset(timer, 0, sizeof(*timer));
timer->fd = timerfd_create(CLOCK_REALTIME, 0);
if (timer->fd < 0) {
fprintf(stderr, "failed to create timer: %s (%d)\n",
strerror(errno), errno);
goto err_free_timer;
}
return timer;
err_free_timer:
free(timer);
return NULL;
}
void timer_set_fps(struct timer *timer, int fps)
{
int ns_per_frame = 1000000000 / fps;
timer->settings.it_value.tv_nsec = ns_per_frame;
timer->settings.it_interval.tv_nsec = ns_per_frame;
}
int timer_arm(struct timer *timer)
{
int ret;
ret = timerfd_settime(timer->fd, 0, &timer->settings, NULL);
if (ret)
fprintf(stderr, "failed to change timer settings: %s (%d)\n",
strerror(errno), errno);
return ret;
}
int timer_disarm(struct timer *timer)
{
static const struct itimerspec disable_settings = {
{ 0, 0 },
{ 0, 0 },
};
int ret;
ret = timerfd_settime(timer->fd, 0, &disable_settings, NULL);
if (ret)
fprintf(stderr, "failed to disable timer: %s (%d)\n",
strerror(errno), errno);
return ret;
}
void timer_wait(struct timer *timer)
{
char read_buf[8];
read(timer->fd, read_buf, 8);
}
void timer_destroy(struct timer *timer)
{
close(timer->fd);
free(timer);
}
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