/*	$OpenBSD: times.c,v 1.9 2019/06/28 13:32:41 deraadt Exp $ */
/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/times.h>
#include <sys/resource.h>
#include <time.h>

/*
 * Convert usec to clock ticks; could do (usec * CLK_TCK) / 1000000,
 * but this would overflow if we switch to nanosec.
 */
#define	CONVTCK(r)	(r.tv_sec * CLK_TCK + r.tv_usec / (1000000 / CLK_TCK))

clock_t
times(struct tms *tp)
{
	struct rusage ru;
	struct timespec ts;

	if (getrusage(RUSAGE_SELF, &ru) == -1)
		return ((clock_t)-1);
	tp->tms_utime = CONVTCK(ru.ru_utime);
	tp->tms_stime = CONVTCK(ru.ru_stime);
	if (getrusage(RUSAGE_CHILDREN, &ru) == -1)
		return ((clock_t)-1);
	tp->tms_cutime = CONVTCK(ru.ru_utime);
	tp->tms_cstime = CONVTCK(ru.ru_stime);
	if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
		return ((clock_t)-1);
	return (ts.tv_sec * CLK_TCK + ts.tv_nsec / (1000000000 / CLK_TCK));
}