lib/libkse/thread/thr_nanosleep.c

   1 /*
   2  * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the author nor the names of any co-contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD$
  30  */
  31 #include <stdio.h>
  32 #include <errno.h>
  33 #include <pthread.h>
  34 #include "thr_private.h"
  35
  36 LT10_COMPAT_PRIVATE(__nanosleep);
  37 LT10_COMPAT_PRIVATE(_nanosleep);
  38 LT10_COMPAT_DEFAULT(nanosleep);
  39
  40 __weak_reference(__nanosleep, nanosleep);
  41
  42 int
  43 _nanosleep(const struct timespec *time_to_sleep,
  44     struct timespec *time_remaining)
  45 {
  46         struct pthread  *curthread = _get_curthread();
  47         int             ret = 0;
  48         struct timespec ts, ts1;
  49         struct timespec remaining_time;
  50         struct timespec wakeup_time;
  51
  52         /* Check if the time to sleep is legal: */
  53         if ((time_to_sleep == NULL) || (time_to_sleep->tv_sec < 0) ||
  54             (time_to_sleep->tv_nsec < 0) ||
  55             (time_to_sleep->tv_nsec >= 1000000000)) {
  56                 /* Return an EINVAL error : */
  57                 errno = EINVAL;
  58                 ret = -1;
  59         } else {
  60                 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
  61                         return (__sys_nanosleep(time_to_sleep, time_remaining));
  62
  63                 KSE_GET_TOD(curthread->kse, &ts);
  64
  65                 /* Calculate the time for the current thread to wake up: */
  66                 TIMESPEC_ADD(&wakeup_time, &ts, time_to_sleep);
  67
  68                 THR_LOCK_SWITCH(curthread);
  69                 curthread->interrupted = 0;
  70                 curthread->wakeup_time = wakeup_time;
  71                 THR_SET_STATE(curthread, PS_SLEEP_WAIT);
  72
  73                 /* Reschedule the current thread to sleep: */
  74                 _thr_sched_switch_unlocked(curthread);
  75
  76                 /* Calculate the remaining time to sleep: */
  77                 KSE_GET_TOD(curthread->kse, &ts1);
  78                 remaining_time.tv_sec = time_to_sleep->tv_sec
  79                     + ts.tv_sec - ts1.tv_sec;
  80                 remaining_time.tv_nsec = time_to_sleep->tv_nsec
  81                     + ts.tv_nsec - ts1.tv_nsec;
  82
  83                 /* Check if the nanosecond field has underflowed: */
  84                 if (remaining_time.tv_nsec < 0) {
  85                         /* Handle the underflow: */
  86                         remaining_time.tv_sec -= 1;
  87                         remaining_time.tv_nsec += 1000000000;
  88                 }
  89                 /* Check if the nanosecond field has overflowed: */
  90                 else if (remaining_time.tv_nsec >= 1000000000) {
  91                         /* Handle the overflow: */
  92                         remaining_time.tv_sec += 1;
  93                         remaining_time.tv_nsec -= 1000000000;
  94                 }
  95
  96                 /* Check if the sleep was longer than the required time: */
  97                 if (remaining_time.tv_sec < 0) {
  98                         /* Reset the time left: */
  99                         remaining_time.tv_sec = 0;
 100                         remaining_time.tv_nsec = 0;
 101                 }
 102
 103                 /* Check if the time remaining is to be returned: */
 104                 if (time_remaining != NULL) {
 105                         /* Return the actual time slept: */
 106                         time_remaining->tv_sec = remaining_time.tv_sec;
 107                         time_remaining->tv_nsec = remaining_time.tv_nsec;
 108                 }
 109
 110                 /* Check if the sleep was interrupted: */
 111                 if (curthread->interrupted) {
 112                         /* Return an EINTR error : */
 113                         errno = EINTR;
 114                         ret = -1;
 115                 }
 116         }
 117         return (ret);
 118 }
 119
 120 int
 121 __nanosleep(const struct timespec *time_to_sleep,
 122     struct timespec *time_remaining)
 123 {
 124         struct pthread *curthread = _get_curthread();
 125         int             ret;
 126
 127         _thr_cancel_enter(curthread);
 128         ret = _nanosleep(time_to_sleep, time_remaining);
 129         _thr_cancel_leave(curthread, 1);
 130
 131         return (ret);
 132 }