1 /* vi: set sw=4 ts=4: */
3 * Mini hwclock implementation for busybox
5 * Copyright (C) 2002 Robert Griebl <griebl@gmx.de>
7 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
10 #include <sys/utsname.h>
14 /* Copied from linux/rtc.h to eliminate the kernel dependency */
15 struct linux_rtc_time {
27 #define RTC_SET_TIME _IOW('p', 0x0a, struct linux_rtc_time) /* Set RTC time */
28 #define RTC_RD_TIME _IOR('p', 0x09, struct linux_rtc_time) /* Read RTC time */
30 #if ENABLE_FEATURE_HWCLOCK_LONG_OPTIONS
36 static const char *rtcname;
38 static int xopen_rtc(int flags)
43 rtc = open("/dev/rtc", flags);
46 rtc = open("/dev/rtc0", flags);
49 rtcname = "/dev/misc/rtc";
51 return xopen(rtcname, flags);
54 static time_t read_rtc(int utc)
59 int rtc = xopen_rtc(O_RDONLY);
61 memset(&tm, 0, sizeof(struct tm));
62 if (ioctl(rtc, RTC_RD_TIME, &tm) < 0)
63 bb_perror_msg_and_die("cannot read time from RTC");
64 tm.tm_isdst = -1; /* not known */
70 setenv("TZ", "UTC 0", 1);
78 setenv("TZ", oldtz, 1);
86 static void write_rtc(time_t t, int utc)
89 int rtc = xopen_rtc(O_WRONLY);
91 tm = *(utc ? gmtime(&t) : localtime(&t));
94 if (ioctl(rtc, RTC_SET_TIME, &tm) < 0)
95 bb_perror_msg_and_die("cannot set the RTC time");
100 static void show_clock(int utc)
107 //ptm = localtime(&t); /* Sets 'tzname[]' */
111 cp[strlen(cp) - 1] = '\0';
113 //printf("%s %.6f seconds %s\n", cp, 0.0, utc ? "" : (ptm->tm_isdst ? tzname[1] : tzname[0]));
114 printf("%s 0.000000 seconds\n", cp);
117 static void to_sys_clock(int utc)
120 const struct timezone tz = { timezone/60 - 60*daylight, 0 };
122 tv.tv_sec = read_rtc(utc);
124 if (settimeofday(&tv, &tz))
125 bb_perror_msg_and_die("settimeofday() failed");
128 static void from_sys_clock(int utc)
132 gettimeofday(&tv, NULL);
133 //if (gettimeofday(&tv, NULL))
134 // bb_perror_msg_and_die("gettimeofday() failed");
135 write_rtc(tv.tv_sec, utc);
138 #ifdef CONFIG_FEATURE_HWCLOCK_ADJTIME_FHS
139 # define ADJTIME_PATH "/var/lib/hwclock/adjtime"
141 # define ADJTIME_PATH "/etc/adjtime"
143 static int check_utc(void)
146 FILE *f = fopen(ADJTIME_PATH, "r");
149 RESERVE_CONFIG_BUFFER(buffer, 128);
151 while (fgets(buffer, sizeof(buffer), f)) {
152 int len = strlen(buffer);
154 while (len && isspace(buffer[len - 1]))
159 if (strncmp(buffer, "UTC", 3) == 0) {
165 RELEASE_CONFIG_BUFFER(buffer);
170 #define HWCLOCK_OPT_LOCALTIME 0x01
171 #define HWCLOCK_OPT_UTC 0x02
172 #define HWCLOCK_OPT_SHOW 0x04
173 #define HWCLOCK_OPT_HCTOSYS 0x08
174 #define HWCLOCK_OPT_SYSTOHC 0x10
175 #define HWCLOCK_OPT_RTCFILE 0x20
177 int hwclock_main(int argc, char **argv);
178 int hwclock_main(int argc, char **argv)
183 #if ENABLE_FEATURE_HWCLOCK_LONG_OPTIONS
184 static const struct option hwclock_long_options[] = {
185 { "localtime", 0, 0, 'l' },
186 { "utc", 0, 0, 'u' },
187 { "show", 0, 0, 'r' },
188 { "hctosys", 0, 0, 's' },
189 { "systohc", 0, 0, 'w' },
190 { "file", 1, 0, 'f' },
193 applet_long_options = hwclock_long_options;
195 opt_complementary = "?:r--ws:w--rs:s--wr:l--u:u--l";
196 opt = getopt32(argc, argv, "lurswf:", &rtcname);
198 /* If -u or -l wasn't given check if we are using utc */
199 if (opt & (HWCLOCK_OPT_UTC | HWCLOCK_OPT_LOCALTIME))
200 utc = opt & HWCLOCK_OPT_UTC;
204 if (opt & HWCLOCK_OPT_HCTOSYS) {
208 if (opt & HWCLOCK_OPT_SYSTOHC) {
212 /* default HWCLOCK_OPT_SHOW */