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/*
* 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)
static char sccsid[] = "@(#)sleep.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/time.h>
#include <signal.h>
#include <unistd.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
#endif
#define setvec(vec, a) \
vec.sv_handler = a; vec.sv_mask = vec.sv_onstack = 0
#if !defined(_THREAD_SAFE) && !defined(USE_NANOSLEEP)
static int ringring;
#endif
static void
sleephandler()
{
#if !defined(_THREAD_SAFE) && !defined(USE_NANOSLEEP)
ringring = 1;
#endif
}
unsigned int
sleep(seconds)
unsigned int seconds;
{
#if defined(_THREAD_SAFE) || defined(USE_NANOSLEEP)
struct timespec time_to_sleep;
struct timespec time_remaining;
struct sigvec vec, ovec;
if (seconds != 0) {
time_to_sleep.tv_sec = seconds;
time_to_sleep.tv_nsec = 0;
setvec(vec, sleephandler);
(void) sigvec(SIGALRM, &vec, &ovec);
/* XXX race here.. a SIGALRM right _now_ could be lost */
nanosleep(&time_to_sleep, &time_remaining);
(void) sigvec(SIGALRM, &ovec, (struct sigvec *)0);
seconds = time_remaining.tv_sec;
if (time_remaining.tv_nsec > 0)
seconds++; /* round up */
}
return (seconds);
#else
register struct itimerval *itp;
struct itimerval itv, oitv;
struct sigvec vec, ovec;
long omask;
static void sleephandler();
itp = &itv;
if (!seconds)
return 0;
timerclear(&itp->it_interval);
timerclear(&itp->it_value);
if (setitimer(ITIMER_REAL, itp, &oitv) < 0)
return seconds;
itp->it_value.tv_sec = seconds;
if (timerisset(&oitv.it_value)) {
if (timercmp(&oitv.it_value, &itp->it_value, >))
oitv.it_value.tv_sec -= itp->it_value.tv_sec;
else {
itp->it_value = oitv.it_value;
/*
* This is a hack, but we must have time to return
* from the setitimer after the alarm or else it'll
* be restarted. And, anyway, sleep never did
* anything more than this before.
*/
oitv.it_value.tv_sec = 1;
oitv.it_value.tv_usec = 0;
}
}
setvec(vec, sleephandler);
(void) sigvec(SIGALRM, &vec, &ovec);
omask = sigblock(sigmask(SIGALRM));
ringring = 0;
(void) setitimer(ITIMER_REAL, itp, (struct itimerval *)0);
while (!ringring)
sigpause(omask &~ sigmask(SIGALRM));
(void) sigvec(SIGALRM, &ovec, (struct sigvec *)0);
(void) sigsetmask(omask);
(void) setitimer(ITIMER_REAL, &oitv, (struct itimerval *)0);
return 0;
#endif
}
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