#include "sys/asoundlib.h"
#include "time.h"
#include <sched.h>

main()
{
	snd_timer_t *th;
	snd_timer_general_info_t geninfo;
	snd_timer_select_t tselect;
	snd_timer_info_t info;
	snd_timer_params_t params;
	snd_timer_status_t status;
	snd_timer_read_t tbuf;
	char buf[200];
	int n;

	snd_timer_open(&th);

	/* geninfo gives you the number of timers */
	snd_timer_general_info(th, &geninfo);
	printf("Number of timers %d\n", geninfo.count);

	/* Then you can select each of them in turn (only the first here) */
	memset(&tselect, 0, sizeof(tselect));

	/* Use 0 for system 10ms timer and 1 for 1ms timer */
	tselect.data.number = 1;
	snd_timer_select(th, &tselect);

	/* Find out about the selected one */
	snd_timer_info(th, &info);
	printf("info ticks %ld res %ld\n", info.ticks, info.resolution);

	params.flags = SND_TIMER_PSFLG_AUTO;
	params.ticks = 1;
	params.queue_size = 64;
	snd_timer_params(th, &params);

	snd_timer_status(th, &status);

	snd_timer_start(th);

	{
	struct sched_param param;
	int rc;

	param.sched_priority = 1;
	rc = sched_setscheduler(0, SCHED_FIFO, &param);
	}

	for (;;) {
		struct timeval tm;
		int  us;
		int  ms;

		n = snd_timer_read(th, &tbuf, sizeof(tbuf));
		if (n) {
			static int firstsec;
			static int  last;

			gettimeofday(&tm, NULL);

			if (firstsec == 0)
				firstsec = tm.tv_sec;
			if (tm.tv_sec - firstsec > 60)
				break;

			us = tm.tv_usec;
			ms = (tm.tv_usec + 500)/1000;
			if (last && ms - last > 1)
				printf("%ld:%03ld: Missed %d interrupts\n",
					tm.tv_sec, tm.tv_usec/1000, ms - last);

			last = ms;
		} else
			printf("=== n was 0\n");
	}
}