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 /* Check if the time to sleep is legal: */
51 if (time_to_sleep == NULL || time_to_sleep->tv_sec < 0 ||
52 time_to_sleep->tv_nsec < 0 || time_to_sleep->tv_nsec >= 1000000000) {
53 /* Return an EINVAL error : */
57 /* Get the current time: */
58 gettimeofday(&tv, NULL);
59 TIMEVAL_TO_TIMESPEC(&tv, ¤t_time);
61 /* Calculate the time for the current thread to wake up: */
62 _thread_run->wakeup_time.tv_sec = current_time.tv_sec + time_to_sleep->tv_sec;
63 _thread_run->wakeup_time.tv_nsec = current_time.tv_nsec + time_to_sleep->tv_nsec;
65 /* Check if the nanosecond field has overflowed: */
66 if (_thread_run->wakeup_time.tv_nsec >= 1000000000) {
67 /* Wrap the nanosecond field: */
68 _thread_run->wakeup_time.tv_sec += 1;
69 _thread_run->wakeup_time.tv_nsec -= 1000000000;
71 _thread_run->interrupted = 0;
73 /* Reschedule the current thread to sleep: */
74 _thread_kern_sched_state(PS_SLEEP_WAIT, __FILE__, __LINE__);
76 /* Get the current time: */
77 gettimeofday(&tv, NULL);
78 TIMEVAL_TO_TIMESPEC(&tv, ¤t_time1);
80 /* Calculate the remaining time to sleep: */
81 remaining_time.tv_sec = time_to_sleep->tv_sec + current_time.tv_sec - current_time1.tv_sec;
82 remaining_time.tv_nsec = time_to_sleep->tv_nsec + current_time.tv_nsec - current_time1.tv_nsec;
84 /* Check if the nanosecond field has underflowed: */
85 if (remaining_time.tv_nsec < 0) {
86 /* Handle the underflow: */
87 remaining_time.tv_sec -= 1;
88 remaining_time.tv_nsec += 1000000000;
91 /* Check if the nanosecond field has overflowed: */
92 if (remaining_time.tv_nsec >= 1000000000) {
93 /* Handle the overflow: */
94 remaining_time.tv_sec += 1;
95 remaining_time.tv_nsec -= 1000000000;
98 /* Check if the sleep was longer than the required time: */
99 if (remaining_time.tv_sec < 0) {
100 /* Reset the time left: */
101 remaining_time.tv_sec = 0;
102 remaining_time.tv_nsec = 0;
105 /* Check if the time remaining is to be returned: */
106 if (time_remaining != NULL) {
107 /* Return the actual time slept: */
108 time_remaining->tv_sec = remaining_time.tv_sec;
109 time_remaining->tv_nsec = remaining_time.tv_nsec;
112 /* Check if the sleep was interrupted: */
113 if (_thread_run->interrupted) {
114 /* Return an EINTR error : */