/* vi: set sw=4 ts=4: */ /* * Mini hwclock implementation for busybox * * Copyright (C) 2002 Robert Griebl * * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ #include #include #include #include "busybox.h" /* Copied from linux/rtc.h to eliminate the kernel dependency */ struct linux_rtc_time { int tm_sec; int tm_min; int tm_hour; int tm_mday; int tm_mon; int tm_year; int tm_wday; int tm_yday; int tm_isdst; }; #define RTC_SET_TIME _IOW('p', 0x0a, struct linux_rtc_time) /* Set RTC time */ #define RTC_RD_TIME _IOR('p', 0x09, struct linux_rtc_time) /* Read RTC time */ #if ENABLE_FEATURE_HWCLOCK_LONG_OPTIONS # ifndef _GNU_SOURCE # define _GNU_SOURCE # endif #endif static const char *rtcname; static int xopen_rtc(int flags) { int rtc; if (!rtcname) { rtc = open("/dev/rtc", flags); if (rtc >= 0) return rtc; rtc = open("/dev/rtc0", flags); if (rtc >= 0) return rtc; rtcname = "/dev/misc/rtc"; } return xopen(rtcname, flags); } static time_t read_rtc(int utc) { struct tm tm; char *oldtz = 0; time_t t = 0; int rtc = xopen_rtc(O_RDONLY); memset(&tm, 0, sizeof(struct tm)); if (ioctl(rtc, RTC_RD_TIME, &tm) < 0 ) bb_perror_msg_and_die("cannot read time from RTC"); tm.tm_isdst = -1; /* not known */ close(rtc); if (utc) { oldtz = getenv("TZ"); setenv("TZ", "UTC 0", 1); tzset(); } t = mktime(&tm); if (utc) { if (oldtz) setenv("TZ", oldtz, 1); else unsetenv("TZ"); tzset(); } return t; } static void write_rtc(time_t t, int utc) { struct tm tm; int rtc = xopen_rtc(O_WRONLY); tm = *(utc ? gmtime(&t) : localtime(&t)); tm.tm_isdst = 0; if (ioctl(rtc, RTC_SET_TIME, &tm) < 0) bb_perror_msg_and_die("cannot set the RTC time"); close(rtc); } static int show_clock(int utc) { struct tm *ptm; time_t t; RESERVE_CONFIG_BUFFER(buffer, 64); t = read_rtc(utc); ptm = localtime(&t); /* Sets 'tzname[]' */ safe_strncpy(buffer, ctime(&t), 64); if (buffer[0]) buffer[strlen(buffer) - 1] = 0; //printf("%s %.6f seconds %s\n", buffer, 0.0, utc ? "" : (ptm->tm_isdst ? tzname[1] : tzname[0])); printf( "%s %.6f seconds\n", buffer, 0.0); RELEASE_CONFIG_BUFFER(buffer); return 0; } static int to_sys_clock(int utc) { struct timeval tv = { 0, 0 }; const struct timezone tz = { timezone/60 - 60*daylight, 0 }; tv.tv_sec = read_rtc(utc); if (settimeofday(&tv, &tz)) bb_perror_msg_and_die("settimeofday() failed"); return 0; } static int from_sys_clock(int utc) { struct timeval tv = { 0, 0 }; struct timezone tz = { 0, 0 }; if (gettimeofday(&tv, &tz)) bb_perror_msg_and_die("gettimeofday() failed"); write_rtc(tv.tv_sec, utc); return 0; } #ifdef CONFIG_FEATURE_HWCLOCK_ADJTIME_FHS # define ADJTIME_PATH "/var/lib/hwclock/adjtime" #else # define ADJTIME_PATH "/etc/adjtime" #endif static int check_utc(void) { int utc = 0; FILE *f = fopen(ADJTIME_PATH, "r"); if (f) { RESERVE_CONFIG_BUFFER(buffer, 128); while (fgets(buffer, sizeof(buffer), f)) { int len = strlen(buffer); while (len && isspace(buffer[len - 1])) len--; buffer[len] = 0; if (strncmp(buffer, "UTC", 3) == 0 ) { utc = 1; break; } } fclose(f); RELEASE_CONFIG_BUFFER(buffer); } return utc; } #define HWCLOCK_OPT_LOCALTIME 0x01 #define HWCLOCK_OPT_UTC 0x02 #define HWCLOCK_OPT_SHOW 0x04 #define HWCLOCK_OPT_HCTOSYS 0x08 #define HWCLOCK_OPT_SYSTOHC 0x10 #define HWCLOCK_OPT_RTCFILE 0x20 int hwclock_main(int argc, char **argv ); int hwclock_main(int argc, char **argv ) { unsigned opt; int utc; #if ENABLE_FEATURE_HWCLOCK_LONG_OPTIONS static const struct option hwclock_long_options[] = { { "localtime", 0, 0, 'l' }, { "utc", 0, 0, 'u' }, { "show", 0, 0, 'r' }, { "hctosys", 0, 0, 's' }, { "systohc", 0, 0, 'w' }, { "file", 1, 0, 'f' }, { 0, 0, 0, 0 } }; applet_long_options = hwclock_long_options; #endif opt_complementary = "?:r--ws:w--rs:s--wr:l--u:u--l"; opt = getopt32(argc, argv, "lurswf:", &rtcname); /* If -u or -l wasn't given check if we are using utc */ if (opt & (HWCLOCK_OPT_UTC | HWCLOCK_OPT_LOCALTIME)) utc = opt & HWCLOCK_OPT_UTC; else utc = check_utc(); if (opt & HWCLOCK_OPT_HCTOSYS) { return to_sys_clock(utc); } else if (opt & HWCLOCK_OPT_SYSTOHC) { return from_sys_clock(utc); } else { /* default HWCLOCK_OPT_SHOW */ return show_clock(utc); } }