diff options
| -rw-r--r-- | util-linux/hwclock.c | 69 |
1 files changed, 50 insertions, 19 deletions
diff --git a/util-linux/hwclock.c b/util-linux/hwclock.c index 44cb479..77aa2d7 100644 --- a/util-linux/hwclock.c +++ b/util-linux/hwclock.c @@ -153,14 +153,12 @@ static void set_kernel_tz(const struct timezone *tz) * then system time is wrong - it is offset by timezone. * --systz option corrects system time if RTC is in local time, * and (always) sets in-kernel timezone. - * - * This is an alternate option to --hctosys that does not read the - * hardware clock. + * (Unlike --hctosys, it does not read the RTC). * * util-linux's code has this comment: * RTC | settimeofday calls * ------|------------------------------------------------- - * Local | 1) warps system time*, sets PCIL* and kernel tz + * Local | 1st) warps system time*, sets PCIL* and kernel tz * UTC | 1st) locks warp_clock 2nd) sets kernel tz * * only on first call after boot * (PCIL is "persistent_clock_is_local" kernel internal flag, @@ -177,6 +175,9 @@ static void set_kernel_timezone_and_clock(int utc, const struct timeval *hctosys set_kernel_tz(&tz); /* Set kernel's timezone offset based on userspace one */ +//It's tempting to call tzset() and use libc global "timezone" variable +//...but it does NOT include DST shift (IOW: it's WRONG, usually by one hour, +//if DST is in effect!) Thus this ridiculous dance: cur = time(NULL); broken = localtime(&cur); tz.tz_minuteswest = -broken->tm_gmtoff / 60; @@ -321,30 +322,58 @@ static void from_sys_clock(const char **pp_rtcname, int utc) close(rtc); } +// hwclock from util-linux 2.36.1 +// hwclock [function] [option...] +//Functions: +// -r, --show display the RTC time +// --get display drift corrected RTC time +// --set set the RTC according to --date +// -s, --hctosys set the system time from the RTC +// -w, --systohc set the RTC from the system time +// --systz send timescale configurations to the kernel +// -a, --adjust adjust the RTC to account for systematic drift +// --predict predict the drifted RTC time according to --date +//Options: +// -u, --utc the RTC timescale is UTC +// -l, --localtime the RTC timescale is Local +// -f, --rtc <file> use an alternate file to /dev/rtc0 +// --directisa use the ISA bus instead of /dev/rtc0 access +// --date <time> date/time input for --set and --predict +// --delay <sec> delay used when set new RTC time +// --update-drift update the RTC drift factor +// --noadjfile do not use /etc/adjtime +// --adjfile <file> use an alternate file to /etc/adjtime +// --test dry run; implies --verbose +// -v, --verbose display more details + +//usage:#if ENABLE_FEATURE_HWCLOCK_ADJTIME_FHS +//usage:# define ADJTIME_PATH "/var/lib/hwclock/adjtime" +//usage:#else +//usage:# define ADJTIME_PATH "/etc/adjtime" +//usage:#endif //usage:#define hwclock_trivial_usage //usage: IF_LONG_OPTS( -//usage: "[-swu] [--systz] [--localtime] [-f FILE]" +//usage: "[-swul] [--systz] [-f DEV]" //usage: ) //usage: IF_NOT_LONG_OPTS( -//usage: "[-swtlu] [-f FILE]" +//usage: "[-swult] [-f DEV]" //usage: ) //usage:#define hwclock_full_usage "\n\n" //usage: "Show or set hardware clock (RTC)\n" -///////: "\n -r Show hardware clock time" +///////: "\n -r Show RTC time" ///////-r is default, don't bother showing it in help -//usage: "\n -s Set system time from hardware clock" -//usage: "\n -w Set hardware clock from system time" +//usage: "\n -s Set system time from RTC" +//usage: "\n -w Set RTC from system time" //usage: IF_LONG_OPTS( //usage: "\n --systz Set in-kernel timezone, correct system time" +//usage: "\n if RTC is kept in local time" //usage: ) -//usage: "\n if hardware clock is in local time" -//usage: "\n -u Assume hardware clock is kept in UTC" -//usage: IF_LONG_OPTS( -//usage: "\n --localtime Assume hardware clock is kept in local time" -//usage: ) -//usage: "\n -f FILE Use specified device (e.g. /dev/rtc2)" +//usage: "\n -f DEV Use specified device (e.g. /dev/rtc2)" +//usage: "\n -u Assume RTC is kept in UTC" +//usage: "\n -l Assume RTC is kept in local time" +//usage: "\n (if neither is given, read from "ADJTIME_PATH")" -//TODO: get rid of incompatible -t and -l aliases to --systz and --localtime +//TODO: get rid of incompatible -t alias to --systz? #define HWCLOCK_OPT_LOCALTIME 0x01 #define HWCLOCK_OPT_UTC 0x02 @@ -362,7 +391,7 @@ int hwclock_main(int argc UNUSED_PARAM, char **argv) int utc; #if ENABLE_LONG_OPTS static const char hwclock_longopts[] ALIGN1 = - "localtime\0" No_argument "l" /* short opt is non-standard */ + "localtime\0" No_argument "l" "utc\0" No_argument "u" "show\0" No_argument "r" "hctosys\0" No_argument "s" @@ -372,12 +401,14 @@ int hwclock_main(int argc UNUSED_PARAM, char **argv) ; #endif opt = getopt32long(argv, - "^lurswtf:" "\0" "r--wst:w--rst:s--wrt:t--rsw:l--u:u--l", + "^""lurswtf:v" /* -v is accepted and ignored */ + "\0" + "r--wst:w--rst:s--wrt:t--rsw:l--u:u--l", hwclock_longopts, &rtcname ); - /* If -u or -l wasn't given check if we are using utc */ + /* 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 |