1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
|
/*
* 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>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
nanosleep(const struct timespec * time_to_sleep,
struct timespec * time_remaining)
{
int ret = 0;
struct timespec current_time;
struct timespec current_time1;
struct timespec remaining_time;
struct timeval tv;
/* 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 {
/* Get the current time: */
gettimeofday(&tv, NULL);
TIMEVAL_TO_TIMESPEC(&tv, ¤t_time);
/* Calculate the time for the current thread to wake up: */
_thread_run->wakeup_time.tv_sec = current_time.tv_sec + time_to_sleep->tv_sec;
_thread_run->wakeup_time.tv_nsec = current_time.tv_nsec + time_to_sleep->tv_nsec;
/* Check if the nanosecond field has overflowed: */
if (_thread_run->wakeup_time.tv_nsec >= 1000000000) {
/* Wrap the nanosecond field: */
_thread_run->wakeup_time.tv_sec += 1;
_thread_run->wakeup_time.tv_nsec -= 1000000000;
}
_thread_run->interrupted = 0;
/* Reschedule the current thread to sleep: */
_thread_kern_sched_state(PS_SLEEP_WAIT, __FILE__, __LINE__);
/* Get the current time: */
gettimeofday(&tv, NULL);
TIMEVAL_TO_TIMESPEC(&tv, ¤t_time1);
/* Calculate the remaining time to sleep: */
remaining_time.tv_sec = time_to_sleep->tv_sec + current_time.tv_sec - current_time1.tv_sec;
remaining_time.tv_nsec = time_to_sleep->tv_nsec + current_time.tv_nsec - current_time1.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: */
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 (_thread_run->interrupted) {
/* Return an EINTR error : */
errno = EINTR;
ret = -1;
}
}
return (ret);
}
#endif
|
