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
|
/*
* NVRAM WakeUp
* Copyright (C) 2001-2003, Sergei Haller.
*
* $Id: gmt-test.c 762 2004-07-21 12:19:57Z bistr-o-math $
*
* Contributed by Dr. Werner Fink <werner@suse.de>
* Added some changes/speedups by Dr. Werner Fink and me.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#define CVSREV_gmt_test_c \
"$Id: gmt-test.c 762 2004-07-21 12:19:57Z bistr-o-math $"
#include <time.h>
#include <linux/rtc.h>
#include <sys/ioctl.h>
#include <syslog.h>
#include <stdlib.h>
#include "nvram-wakeup.h"
int compare_ltm_rtc(void)
{
/* The size of `struct tm' is bigger than the size of `struct rtc_time'. */
/* Nevertheless, the first 9 entries DO have the same size and the same */
/* meaning. We don't use other entries. */
/* Thus we just use the same part of the memory instead of using memcpy. */
struct tm rtc;
struct rtc_time *rtc_tm = (struct rtc_time *)(void *)(&rtc);
time_t diff;
/* fd_rtc should have been opened by main */
if (ioctl(fd_rtc, RTC_RD_TIME, rtc_tm) == -1) {
nvprintf(LOG_ERR, "%s: %m\n", "ioctl RTC_RD_TIME");
return -2;
}
nvprintf(LOG_DEBUG, "Hardware clock: %4d-%02d-%02d %02d:%02d:%02d\n",
rtc.tm_year+1900, rtc.tm_mon+1, rtc.tm_mday,
rtc.tm_hour, rtc.tm_min, rtc.tm_sec );
rtc.tm_isdst = -1; /* we don't know if DST is active */
diff = time(NULL) - mktime(&rtc);
nvprintf(LOG_DEBUG, "rtc.tm_isdst : %d\n", rtc.tm_isdst);
nvprintf(LOG_DEBUG, "rtc.tm_gmtoff: %d\n", rtc.tm_gmtoff);
nvprintf(LOG_DEBUG, "diff : %d\n", diff);
/*
* Test if diff is zero or equal to the value of timezone
* (which should be if RTC time is synchronously with system time ...
* nevertheless we allow an offset of 5 minutes.)
*/
/* RTC time is running in UTC or */
/* RTC time is running in localtime (which _is_ UTC) */
if (abs(diff-rtc.tm_gmtoff) < 5*60)
return 1;
/* RTC time is running in localtime (which is _not_ UTC) */
if (abs(diff) < 5*60)
return 0;
/* RTC time is not synchronously with system time */
return -1;
}
|
