/**
 * Convenience methods which interact with the system clock in microseconds
 * UTC.
 *
 * Author: adambuckley@gmx.net
 * Version: $Id: utc.c,v 1.2 2002/05/23 12:13:55 adam Exp $
 */

/**
 * This source code is copyright (c) 2002 Adam Buckley, <adambuckley@gmx.net>.
 *
 * This source code is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU General Public License as published by the Free 
 * Software Foundation; either version 2 of the License, or (at your option) 
 * any later version.
 *
 * This source code is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 
 * more details.
 *
 * The GNU General Public License can be found at
 * http://www.gnu.org/licenses/gpl.html
 */

#ifndef ADAMLIB_UTC_C
#define ADAMLIB_UTC_C

#include <sys/time.h>
#include <unistd.h>



/**
 * Returns the number of microseconds elapsed since 00:00:00 UTC,
 * January 1, 1970.
 */
long long getUtc()
{
	struct timeval tv;
	gettimeofday(&tv, 0);
	return (long long) tv.tv_sec * 1000000 + tv.tv_usec;
}



/**
 * Blocks execution until absolute time 'waitUntilTime', which is specified in
 * microseconds UTC.
 */
void waitUntil(long long waitUntilTime)
{
	int timeToWait = waitUntilTime - getUtc();
	if(timeToWait > 0) usleep(timeToWait);
}

#endif