/*
 * KURT: KU Real Time Linux
 * $ProductId: KURT/linux/rt:rt.c 1.4 $
 *
 * Copyright (C) 1997 by the University of Kansas Center for Research,
 * Inc.  This software was developed by the Information and
 * Telecommunication Technology Center (ITTC) at the University of
 * Kansas.  Partial funding for this project was provided by Sprint. This
 * software may be used and distributed according to the terms of the GNU
 * Public License, incorporated herein by reference.  Neither ITTC nor
 * Sprint accept any liability whatsoever for this product.
 *
 * This project was developed under the direction of Dr. Douglas Niehaus.
 * 
 * Authors: Balaji S.
 *
 * Please send bug-reports/suggestions/comments to realtime@ittc.ukans.edu
 * 
 * Further details about this project can be obtained at
 *    http://hegel.ittc.ukans.edu/projects/kurt/ 
 */
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <linux/config.h>

#ifdef CONFIG_UTIME
#include <linux/mutime.h>
#endif
#include <linux/signal.h>
#include <signal.h>
#include <sched.h>
#include <linux/rt.h>

void IntProc(int i)
{
	struct rtparams param;
	int retval;

	retval = get_rtparams(0, &param);
	if (!retval) {
		printf("IntProc called for process with rt_id %d\n",
		       param.rt_id);
	}

	/* Make this a normal process
	 */
	param.rt_id = 0;
	if (set_rtparams(0, SCHED_OTHER, &param)) {
		perror("set_rtparams: ");
		exit(1);
	}
	exit(0);
}

void do_stuff(void)
{
	struct timeval time;
	static int i = 0;

	/* Just get the time and print it
	 */
	gettimeofday(&time, NULL);
	printf("(%d)Time is %d.%d.\n", i++, (int)time.tv_sec, 
	       (int)time.tv_usec);
}

int main(int argc, char **argv)
{
	struct rtparams rt_param;

	signal(SIGINT, IntProc);

	if (argc != 2) {
		fprintf(stderr, "Usage : %s <rtid>\n", argv[0]);
		exit(1);
	}
	/* set the scheduler for this process to be sched_kurt
	 * and then set the rt_id of this procss properly
	 */
	rt_param.rt_id = atoi(argv[1]);
	rt_param.proc_req = 0;
	rt_param.period  = 0;
	rt_param.priority = MAX_KURT_PRIORITY;
	if (set_rtparams(0, SCHED_KURT, &rt_param) < 0) {
		perror("set_rtparams:");
		exit(1);
	} else {
		get_rtparams(0, &rt_param);
		printf("process rt_id = %d.\n", rt_param.rt_id);
	}

	while (1) {
		/* suspend the process till it is scheduled in
		 * force it to suspend....If the parameter is 0 then rt_suspend
		 * would not suspend if the kernel is not in real time mode
		 */
		if (rt_suspend(SUSPEND_IF_NRT | START_SCHED)) {
			perror("rt_suspend ");
			exit(0);
		}
		do_stuff();
	}
	return 0;
}