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-rw-r--r--busybox/util-linux/hwclock.c230
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diff --git a/busybox/util-linux/hwclock.c b/busybox/util-linux/hwclock.c
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1/* vi: set sw=4 ts=4: */
2/*
3 * Mini hwclock implementation for busybox
4 *
5 * Copyright (C) 2002 Robert Griebl <griebl@gmx.de>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21*/
22
23
24#include <sys/ioctl.h>
25#include <sys/time.h>
26#include <sys/utsname.h>
27#include <ctype.h>
28#include <fcntl.h>
29#include <getopt.h>
30#include <stdlib.h>
31#include <string.h>
32#include <syslog.h>
33#include <time.h>
34#include <unistd.h>
35#include "busybox.h"
36
37/* Copied from linux/rtc.h to eliminate the kernel dependency */
38struct linux_rtc_time {
39 int tm_sec;
40 int tm_min;
41 int tm_hour;
42 int tm_mday;
43 int tm_mon;
44 int tm_year;
45 int tm_wday;
46 int tm_yday;
47 int tm_isdst;
48};
49
50#define RTC_SET_TIME _IOW('p', 0x0a, struct linux_rtc_time) /* Set RTC time */
51#define RTC_RD_TIME _IOR('p', 0x09, struct linux_rtc_time) /* Read RTC time */
52
53#ifdef CONFIG_FEATURE_HWCLOCK_LONGOPTIONS
54# ifndef _GNU_SOURCE
55# define _GNU_SOURCE
56# endif
57#endif
58
59static time_t read_rtc(int utc)
60{
61 int rtc;
62 struct tm tm;
63 char *oldtz = 0;
64 time_t t = 0;
65
66 if (( rtc = open ( "/dev/rtc", O_RDONLY )) < 0 ) {
67 if (( rtc = open ( "/dev/misc/rtc", O_RDONLY )) < 0 )
68 bb_perror_msg_and_die ( "Could not access RTC" );
69 }
70 memset ( &tm, 0, sizeof( struct tm ));
71 if ( ioctl ( rtc, RTC_RD_TIME, &tm ) < 0 )
72 bb_perror_msg_and_die ( "Could not read time from RTC" );
73 tm. tm_isdst = -1; // not known
74
75 close ( rtc );
76
77 if ( utc ) {
78 oldtz = getenv ( "TZ" );
79 setenv ( "TZ", "UTC 0", 1 );
80 tzset ( );
81 }
82
83 t = mktime ( &tm );
84
85 if ( utc ) {
86 if ( oldtz )
87 setenv ( "TZ", oldtz, 1 );
88 else
89 unsetenv ( "TZ" );
90 tzset ( );
91 }
92 return t;
93}
94
95static void write_rtc(time_t t, int utc)
96{
97 int rtc;
98 struct tm tm;
99
100 if (( rtc = open ( "/dev/rtc", O_WRONLY )) < 0 ) {
101 if (( rtc = open ( "/dev/misc/rtc", O_WRONLY )) < 0 )
102 bb_perror_msg_and_die ( "Could not access RTC" );
103 }
104
105 tm = *( utc ? gmtime ( &t ) : localtime ( &t ));
106 tm. tm_isdst = 0;
107
108 if ( ioctl ( rtc, RTC_SET_TIME, &tm ) < 0 )
109 bb_perror_msg_and_die ( "Could not set the RTC time" );
110
111 close ( rtc );
112}
113
114static int show_clock(int utc)
115{
116 struct tm *ptm;
117 time_t t;
118 char buffer [64];
119
120 t = read_rtc ( utc );
121 ptm = localtime ( &t ); /* Sets 'tzname[]' */
122
123 safe_strncpy ( buffer, ctime ( &t ), sizeof( buffer ));
124 if ( buffer [0] )
125 buffer [bb_strlen ( buffer ) - 1] = 0;
126
127 //printf ( "%s %.6f seconds %s\n", buffer, 0.0, utc ? "" : ( ptm-> tm_isdst ? tzname [1] : tzname [0] ));
128 printf ( "%s %.6f seconds\n", buffer, 0.0 );
129
130 return 0;
131}
132
133static int to_sys_clock(int utc)
134{
135 struct timeval tv = { 0, 0 };
136 const struct timezone tz = { timezone/60 - 60*daylight, 0 };
137
138 tv. tv_sec = read_rtc ( utc );
139
140 if ( settimeofday ( &tv, &tz ))
141 bb_perror_msg_and_die ( "settimeofday() failed" );
142
143 return 0;
144}
145
146static int from_sys_clock(int utc)
147{
148 struct timeval tv = { 0, 0 };
149 struct timezone tz = { 0, 0 };
150
151 if ( gettimeofday ( &tv, &tz ))
152 bb_perror_msg_and_die ( "gettimeofday() failed" );
153
154 write_rtc ( tv. tv_sec, utc );
155 return 0;
156}
157
158
159static int check_utc(void)
160{
161 int utc = 0;
162 FILE *f = fopen ( "/var/lib/hwclock/adjtime", "r" );
163
164 if ( f ) {
165 char buffer [128];
166
167 while ( fgets ( buffer, sizeof( buffer ), f )) {
168 int len = bb_strlen ( buffer );
169
170 while ( len && isspace ( buffer [len - 1] ))
171 len--;
172
173 buffer [len] = 0;
174
175 if ( strncmp ( buffer, "UTC", 3 ) == 0 ) {
176 utc = 1;
177 break;
178 }
179 }
180 fclose ( f );
181 }
182 return utc;
183}
184
185#define HWCLOCK_OPT_LOCALTIME 1
186#define HWCLOCK_OPT_UTC 2
187#define HWCLOCK_OPT_SHOW 4
188#define HWCLOCK_OPT_HCTOSYS 8
189#define HWCLOCK_OPT_SYSTOHC 16
190
191extern int hwclock_main ( int argc, char **argv )
192{
193 unsigned long opt;
194 int utc;
195
196#ifdef CONFIG_FEATURE_HWCLOCK_LONGOPTIONS
197static const struct option hwclock_long_options[] = {
198 { "localtime", 0, 0, 'l' },
199 { "utc", 0, 0, 'u' },
200 { "show", 0, 0, 'r' },
201 { "hctosys", 0, 0, 's' },
202 { "systohc", 0, 0, 'w' },
203 { 0, 0, 0, 0 }
204 };
205 bb_applet_long_options = hwclock_long_options;
206#endif
207
208 bb_opt_complementaly = "r~ws:w~rs:s~wr:l~u:u~l";
209 opt = bb_getopt_ulflags(argc, argv, "lursw");
210 /* Check only one mode was given */
211 if(opt & 0x80000000UL) {
212 bb_show_usage();
213 }
214
215 /* If -u or -l wasn't given check if we are using utc */
216 if (opt & (HWCLOCK_OPT_UTC | HWCLOCK_OPT_LOCALTIME))
217 utc = opt & HWCLOCK_OPT_UTC;
218 else
219 utc = check_utc();
220
221 if (opt & HWCLOCK_OPT_HCTOSYS) {
222 return to_sys_clock ( utc );
223 }
224 else if (opt & HWCLOCK_OPT_SYSTOHC) {
225 return from_sys_clock ( utc );
226 } else {
227 /* default HWCLOCK_OPT_SHOW */
228 return show_clock ( utc );
229 }
230}