2 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by John Birrell.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 #include "pthread_private.h"
41 nanosleep(const struct timespec * time_to_sleep,
42 struct timespec * time_remaining)
45 struct timespec current_time;
46 struct timespec current_time1;
47 struct timespec remaining_time;
50 _thread_enter_cancellation_point();
51 /* Check if the time to sleep is legal: */
52 if (time_to_sleep == NULL || time_to_sleep->tv_sec < 0 ||
53 time_to_sleep->tv_nsec < 0 || time_to_sleep->tv_nsec >= 1000000000) {
54 /* Return an EINVAL error : */
58 /* Get the current time: */
59 gettimeofday(&tv, NULL);
60 TIMEVAL_TO_TIMESPEC(&tv, ¤t_time);
62 /* Calculate the time for the current thread to wake up: */
63 _thread_run->wakeup_time.tv_sec = current_time.tv_sec + time_to_sleep->tv_sec;
64 _thread_run->wakeup_time.tv_nsec = current_time.tv_nsec + time_to_sleep->tv_nsec;
66 /* Check if the nanosecond field has overflowed: */
67 if (_thread_run->wakeup_time.tv_nsec >= 1000000000) {
68 /* Wrap the nanosecond field: */
69 _thread_run->wakeup_time.tv_sec += 1;
70 _thread_run->wakeup_time.tv_nsec -= 1000000000;
72 _thread_run->interrupted = 0;
74 /* Reschedule the current thread to sleep: */
75 _thread_kern_sched_state(PS_SLEEP_WAIT, __FILE__, __LINE__);
77 /* Get the current time: */
78 gettimeofday(&tv, NULL);
79 TIMEVAL_TO_TIMESPEC(&tv, ¤t_time1);
81 /* Calculate the remaining time to sleep: */
82 remaining_time.tv_sec = time_to_sleep->tv_sec + current_time.tv_sec - current_time1.tv_sec;
83 remaining_time.tv_nsec = time_to_sleep->tv_nsec + current_time.tv_nsec - current_time1.tv_nsec;
85 /* Check if the nanosecond field has underflowed: */
86 if (remaining_time.tv_nsec < 0) {
87 /* Handle the underflow: */
88 remaining_time.tv_sec -= 1;
89 remaining_time.tv_nsec += 1000000000;
92 /* Check if the nanosecond field has overflowed: */
93 if (remaining_time.tv_nsec >= 1000000000) {
94 /* Handle the overflow: */
95 remaining_time.tv_sec += 1;
96 remaining_time.tv_nsec -= 1000000000;
99 /* Check if the sleep was longer than the required time: */
100 if (remaining_time.tv_sec < 0) {
101 /* Reset the time left: */
102 remaining_time.tv_sec = 0;
103 remaining_time.tv_nsec = 0;
106 /* Check if the time remaining is to be returned: */
107 if (time_remaining != NULL) {
108 /* Return the actual time slept: */
109 time_remaining->tv_sec = remaining_time.tv_sec;
110 time_remaining->tv_nsec = remaining_time.tv_nsec;
113 /* Check if the sleep was interrupted: */
114 if (_thread_run->interrupted) {
115 /* Return an EINTR error : */
120 _thread_leave_cancellation_point();