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
|
/*
* This file is Copyright (c) 2010 by the GPSD project
* BSD terms apply: see the file COPYING in the distribution root for details.
*/
/*
* We also need to set the value high enough to signal inclusion of
* newer features (like clock_gettime). See the POSIX spec for more info:
* http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html#tag_15_02_01_02
*/
#define _XOPEN_SOURCE 600
#include <stdio.h>
#include <time.h>
#include <sys/time.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <errno.h>
#include <ctype.h>
#include "timespec.h"
/* Convert a normalized timespec to a nice string
* put in it *buf, buf should be at least 22 bytes
*
* the returned buffer will look like, shortest case:
* sign character ' ' or '-'
* one digit of seconds
* decmal point '.'
* 9 digits of nanoSec
*
* So 12 chars, like this: "-0.123456789"
*
* Probable worst case is 10 digits of seconds,
* but standards do not provide hard limits to time_t
* So 21 characters like this: "-2147483647.123456789"
*
* date --date='@2147483647' is: Mon Jan 18 19:14:07 PST 2038
* date --date='@9999999999' is: Sat Nov 20 09:46:39 PST 2286
*
*/
void timespec_str(const struct timespec *ts, char *buf, size_t buf_size)
{
char sign = ' ';
if ( (0 > ts->tv_nsec ) || ( 0 > ts->tv_sec ) ) {
sign = '-';
}
(void) snprintf( buf, buf_size, "%c%lld.%09ld",
sign,
(long long)llabs(ts->tv_sec),
(long)labs(ts->tv_nsec));
}
/* end */
|
