#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>

void
wr_str(char *s)
{
	printf("%s", s);
	fflush(stdout);
}

void
wr_int(int n, int v) /* big endian */
{
	while(n--) putchar((v >> n*8) & 0xff);
	fflush(stdout);
}

void
wr_delta(int v)
{
	char buf[5], *bp;

	if(v == 0){
		putchar(0);
		fflush(stdout);
		return;
	}
	bp = buf;
	while(v){
		*bp++ = v & 0x7f;
		v >>= 7;
	}
	while(--bp != buf) putchar(0x80 | *bp);
	putchar(*bp);
	fflush(stdout);
}

int
now_msec(void)
{
	struct timeval tm;
	gettimeofday(&tm, NULL);
	return tm.tv_sec * 1000 + tm.tv_usec / 1000;
}

void
wr_delta_now(int st_msec, int *sum, int div)
{
	int msec, t;
	msec = now_msec() - st_msec;
	t = div * msec / 500;
	wr_delta(t - *sum);
	*sum = t;
}

void
wait_msec(int msec, int st_msec, int *sum, int div)
{
	int st;
	st = now_msec();
	while(now_msec() - st < msec){
		wr_delta_now(st_msec, sum, div);
		wr_int(1, 0xf8); /* clock */
		usleep(20*1000);
	}
}

int
main(int ac, char **av)
{
	int div, st_msec, sum;

	div = 96;
	wr_str("MThd");
	wr_int(4, 6);
	wr_int(2, 0);
	wr_int(2, 1);
	wr_int(2, div);

	wr_str("MTrk");
	wr_int(4, 0);
	
	sum = -30;
	st_msec = now_msec();

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (0xc<<4) | 0); /* prog_num ch=0 */
	wr_int(1, 50); /* 50 : strings ensamble 2 */

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (0xb<<4) | 0); /* ctl chg ch=0 */
	wr_int(1, 7); /* channel volme msb */
	wr_int(1, 64);

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (9<<4) | 0); /* note on ch=0 */
	wr_int(1, 69); /* A */
	wr_int(1, 64); /* velo */

	wait_msec(500, st_msec, &sum, div);

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (9<<4) | 0); /* note on ch=0 */
	wr_int(1, 73); /* C# */
	wr_int(1, 64); /* velo */

	wait_msec(500, st_msec, &sum, div);

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (9<<4) | 0); /* note on ch=0 */
	wr_int(1, 76); /* E */
	wr_int(1, 64); /* velo */

	wait_msec(3000, st_msec, &sum, div);

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (8<<4) | 0); /* noe off ch=0 */
	wr_int(1, 69); /* A */
	wr_int(1, 0); /* velo */

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (8<<4) | 0); /* noe off ch=0 */
	wr_int(1, 73); /* C# */
	wr_int(1, 0); /* velo */

	wr_delta_now(st_msec, &sum, div);
	wr_int(1, (8<<4) | 0); /* noe off ch=0 */
	wr_int(1, 76); /* E */
	wr_int(1, 0); /* velo */

	wait_msec(1000, st_msec, &sum, div);

	return 0;
}

/* EOF */