freebsd-dev/lib/libc_r/uthread/uthread_nanosleep.c
Julian Elischer 012dfd00b3 Reviewed by: julian
Submitted by:	 john birrel

One version of the pthreads library
another will follow with differnt actions under some cases..
not QUITE complete
1996-01-22 00:23:58 +00:00

88 lines
3.5 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 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 <stdio.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
nanosleep(struct timespec * time_to_sleep, struct timespec * time_remaining)
{
struct timespec current_time;
struct timespec current_time1;
struct timeval tv;
/* Get the current time: */
gettimeofday(&tv, NULL);
TIMEVAL_TO_TIMESPEC(&tv, &current_time);
/* Calculate the time for the current thread to wake up: */
_thread_run->wakeup_time.ts_sec = current_time.ts_sec + time_to_sleep->ts_sec;
_thread_run->wakeup_time.ts_nsec = current_time.ts_nsec + time_to_sleep->ts_nsec;
/* Check if the nanosecond field has overflowed: */
if (_thread_run->wakeup_time.ts_nsec >= 1000000000) {
/* Wrap the nanosecond field: */
_thread_run->wakeup_time.ts_sec += 1;
_thread_run->wakeup_time.ts_nsec -= 1000000000;
}
/* Reschedule the current thread to sleep: */
_thread_kern_sched_state(PS_SLEEP_WAIT, __FILE__, __LINE__);
/* Check if the time remaining is to be returned: */
if (time_remaining != NULL) {
/* Get the current time: */
gettimeofday(&tv, NULL);
TIMEVAL_TO_TIMESPEC(&tv, &current_time1);
/* Return the actual time slept: */
time_remaining->ts_sec = time_to_sleep->ts_sec + current_time1.ts_sec - current_time.ts_sec;
time_remaining->ts_nsec = time_to_sleep->ts_nsec + current_time1.ts_nsec - current_time.ts_nsec;
/* Check if the nanosecond field has underflowed: */
if (time_remaining->ts_nsec < 0) {
/* Handle the underflow: */
time_remaining->ts_sec -= 1;
time_remaining->ts_nsec += 1000000000;
}
/* Check if the sleep was longer than the required time: */
if (time_remaining->ts_sec < 0) {
/* Reset the time teft: */
time_remaining->ts_sec = 0;
time_remaining->ts_nsec = 0;
}
}
return (0);
}
#endif