musiclight2/utils.c

/*
 * vim: sw=2 ts=2 expandtab
 *
 * "THE PIZZA-WARE LICENSE" (derived from "THE BEER-WARE LICENCE"):
 * Thomas Kolb <cfr34k@tkolb.de> wrote this file. As long as you retain this
 * notice you can do whatever you want with this stuff. If we meet some day,
 * and you think this stuff is worth it, you can buy me a pizza in return.
 * - Thomas Kolb
 */

#include <errno.h>

#include <time.h>
#include <stdint.h>

#include "utils.h"

double get_hires_time(void) {
  struct timespec clk;
  clock_gettime(CLOCK_REALTIME, &clk);
  return clk.tv_sec + 1e-9 * clk.tv_nsec;
}

void fsleep(double d) {
  struct timespec ts;

  ts.tv_sec = (time_t)d;
  ts.tv_nsec = (long)(1e9 * (d - (long)d));

  nanosleep(&ts, NULL);
}

void sleep_until(double hires_time) {
  struct timespec tv;
  int ret;

  tv.tv_sec = hires_time;
  tv.tv_nsec = (uint64_t)(1e9 * hires_time) % 1000000000;
	do {
		ret = clock_nanosleep(CLOCK_REALTIME, TIMER_ABSTIME, &tv, NULL);
	} while(ret == EINTR);
}