freebsd-nq/lib/libc/gen/sleep.c
1999-08-28 00:22:10 +00:00

70 lines
2.6 KiB
C

/*
* Copyright (c) 1989, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)sleep.c 8.1 (Berkeley) 6/4/93";
#endif
static char rcsid[] =
"$FreeBSD$";
#endif /* LIBC_SCCS and not lint */
#include <errno.h>
#include <limits.h>
#include <time.h>
#include <unistd.h>
unsigned int
sleep(seconds)
unsigned int seconds;
{
struct timespec time_to_sleep;
struct timespec time_remaining;
/*
* Avoid overflow when `seconds' is huge. This assumes that
* the maximum value for a time_t is >= INT_MAX.
*/
if (seconds > INT_MAX)
return (seconds - INT_MAX + sleep(INT_MAX));
time_to_sleep.tv_sec = seconds;
time_to_sleep.tv_nsec = 0;
if (nanosleep(&time_to_sleep, &time_remaining) != -1)
return (0);
if (errno != EINTR)
return (seconds); /* best guess */
return (time_remaining.tv_sec +
(time_remaining.tv_nsec != 0)); /* round up */
}