freebsd-nq/lib/libkse/thread/thr_nanosleep.c
2006-02-23 21:34:08 +00:00

132 lines
4.4 KiB
C

/*
* Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
* 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 John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <stdio.h>
#include <errno.h>
#include <pthread.h>
#include "thr_private.h"
__weak_reference(__nanosleep, nanosleep);
int
_nanosleep(const struct timespec *time_to_sleep,
struct timespec *time_remaining)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
struct timespec ts, ts1;
struct timespec remaining_time;
struct timespec wakeup_time;
/* Check if the time to sleep is legal: */
if ((time_to_sleep == NULL) || (time_to_sleep->tv_sec < 0) ||
(time_to_sleep->tv_nsec < 0) ||
(time_to_sleep->tv_nsec >= 1000000000)) {
/* Return an EINVAL error : */
errno = EINVAL;
ret = -1;
} else {
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
return (__sys_nanosleep(time_to_sleep, time_remaining));
KSE_GET_TOD(curthread->kse, &ts);
/* Calculate the time for the current thread to wake up: */
TIMESPEC_ADD(&wakeup_time, &ts, time_to_sleep);
THR_LOCK_SWITCH(curthread);
curthread->interrupted = 0;
curthread->wakeup_time = wakeup_time;
THR_SET_STATE(curthread, PS_SLEEP_WAIT);
/* Reschedule the current thread to sleep: */
_thr_sched_switch_unlocked(curthread);
/* Calculate the remaining time to sleep: */
KSE_GET_TOD(curthread->kse, &ts1);
remaining_time.tv_sec = time_to_sleep->tv_sec
+ ts.tv_sec - ts1.tv_sec;
remaining_time.tv_nsec = time_to_sleep->tv_nsec
+ ts.tv_nsec - ts1.tv_nsec;
/* Check if the nanosecond field has underflowed: */
if (remaining_time.tv_nsec < 0) {
/* Handle the underflow: */
remaining_time.tv_sec -= 1;
remaining_time.tv_nsec += 1000000000;
}
/* Check if the nanosecond field has overflowed: */
else if (remaining_time.tv_nsec >= 1000000000) {
/* Handle the overflow: */
remaining_time.tv_sec += 1;
remaining_time.tv_nsec -= 1000000000;
}
/* Check if the sleep was longer than the required time: */
if (remaining_time.tv_sec < 0) {
/* Reset the time left: */
remaining_time.tv_sec = 0;
remaining_time.tv_nsec = 0;
}
/* Check if the time remaining is to be returned: */
if (time_remaining != NULL) {
/* Return the actual time slept: */
time_remaining->tv_sec = remaining_time.tv_sec;
time_remaining->tv_nsec = remaining_time.tv_nsec;
}
/* Check if the sleep was interrupted: */
if (curthread->interrupted) {
/* Return an EINTR error : */
errno = EINTR;
ret = -1;
}
}
return (ret);
}
int
__nanosleep(const struct timespec *time_to_sleep,
struct timespec *time_remaining)
{
struct pthread *curthread = _get_curthread();
int ret;
_thr_cancel_enter(curthread);
ret = _nanosleep(time_to_sleep, time_remaining);
_thr_cancel_leave(curthread, 1);
return (ret);
}