diff options
author | Robert Griebl <griebl@gmx.de> | 2002-07-21 20:50:49 +0400 |
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committer | Robert Griebl <griebl@gmx.de> | 2002-07-21 20:50:49 +0400 |
commit | 1cd044549531ef1c4016ec3c60652dad95b1617f (patch) | |
tree | d552f7d94cac8240a89a5e498b73c0c60299de2c /util-linux/hwclock.c | |
parent | fc78b795758ad04caeadfbb2bbb75e6cefa03785 (diff) |
Initial checkin of a very primitive hwclock replacement
Diffstat (limited to 'util-linux/hwclock.c')
-rw-r--r-- | util-linux/hwclock.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/util-linux/hwclock.c b/util-linux/hwclock.c new file mode 100644 index 000000000..88222e6ba --- /dev/null +++ b/util-linux/hwclock.c @@ -0,0 +1,229 @@ +/* vi: set sw=4 ts=4: */ +/* + * really dumb hwclock implementation for busybox + * Copyright (C) 2002 Robert Griebl <griebl@gmx.de> + * + */ + + +#include <sys/utsname.h> +#include <stdlib.h> +#include <unistd.h> +#include <syslog.h> +#include <string.h> +#include <ctype.h> +#include <fcntl.h> +#include <sys/time.h> +#include <time.h> +#include <linux/rtc.h> +#include <sys/ioctl.h> +#include "busybox.h" + +#ifdef CONFIG_FEATURE_HWCLOCK_LONGOPTIONS +# ifndef _GNU_SOURCE +# define _GNU_SOURCE +# endif +#endif + +#include <getopt.h> + + +enum OpMode { + SHOW, + SYSTOHC, + HCTOSYS +}; + + +time_t read_rtc ( int utc ) +{ + int rtc; + struct tm tm; + char *oldtz = 0; + time_t t = 0; + + if (( rtc = open ( "/dev/rtc", O_RDONLY )) < 0 ) { + if (( rtc = open ( "/dev/misc/rtc", O_RDONLY )) < 0 ) + perror_msg_and_die ( "Could not access RTC" ); + } + memset ( &tm, 0, sizeof( struct tm )); + if ( ioctl ( rtc, RTC_RD_TIME, &tm ) < 0 ) + perror_msg_and_die ( "Could not 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; +} + +void write_rtc ( time_t t, int utc ) +{ + int rtc; + struct tm tm; + + if (( rtc = open ( "/dev/rtc", O_WRONLY )) < 0 ) { + if (( rtc = open ( "/dev/misc/rtc", O_WRONLY )) < 0 ) + perror_msg_and_die ( "Could not access RTC" ); + } + + printf ( "1\n" ); + + tm = *( utc ? gmtime ( &t ) : localtime ( &t )); + tm. tm_isdst = 0; + + printf ( "2\n") ; + + if ( ioctl ( rtc, RTC_SET_TIME, &tm ) < 0 ) + perror_msg_and_die ( "Could not set the RTC time" ); + + close ( rtc ); +} + +int show_clock ( int utc ) +{ + struct tm *ptm; + time_t t; + char buffer [64]; + + t = read_rtc ( utc ); + ptm = localtime ( &t ); /* Sets 'tzname[]' */ + + safe_strncpy ( buffer, ctime ( &t ), sizeof( buffer )); + if ( buffer [0] ) + buffer [xstrlen ( 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 ); + + return 0; +} + +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 )) + perror_msg_and_die ( "settimeofday() failed" ); + + return 0; +} + +int from_sys_clock ( int utc ) +{ + struct timeval tv = { 0, 0 }; + struct timezone tz = { 0, 0 }; + + if ( gettimeofday ( &tv, &tz )) + perror_msg_and_die ( "gettimeofday() failed" ); + + write_rtc ( tv. tv_sec, utc ); + return 0; +} + + +int check_utc ( void ) +{ + int utc = 0; + FILE *f = fopen ( "/etc/adjtime", "r" ); + + if ( f ) { + char buffer [128]; + + while ( fgets ( buffer, sizeof( buffer ), f )) { + int len = xstrlen ( buffer ); + + while ( len && isspace ( buffer [len - 1] )) + len--; + + buffer [len] = 0; + + if ( strncmp ( buffer, "UTC", 3 ) == 0 ) { + utc = 1; + break; + } + } + fclose ( f ); + } + return utc; +} + +extern int hwclock_main ( int argc, char **argv ) +{ + int opt; + enum OpMode mode = SHOW; + int utc = 0; + int utc_arg = 0; + +#ifdef CONFIG_FEATURE_HWCLOCK_LONGOPTIONS + struct option long_options[] = { + { "show", 0, 0, 'r' }, + { "utc", 0, 0, 'u' }, + { "localtime", 0, 0, 'l' }, + { "hctosys", 0, 0, 's' }, + { "systohc", 0, 0, 'w' }, + { 0, 0, 0, 0 } + }; + + while (( opt = getopt_long ( argc, argv, "rwsul", long_options, 0 )) != EOF ) { +#else + while (( opt = getopt ( argc, argv, "rwsul" )) != EOF ) { +#endif + switch ( opt ) { + case 'r': + mode = SHOW; + break; + case 'w': + mode = SYSTOHC; + break; + case 's': + mode = HCTOSYS; + break; + case 'u': + utc = 1; + utc_arg = 1; + break; + case 'l': // -l is not supported by the normal hwclock (only --localtime) + utc = 0; + utc_arg = 1; + break; + default: + show_usage(); + break; + } + } + + if ( !utc_arg ) + utc = check_utc ( ); + + switch ( mode ) { + case SYSTOHC: + return from_sys_clock ( utc ); + + case HCTOSYS: + return to_sys_clock ( utc ); + + case SHOW: + default: + return show_clock ( utc ); + } +} + + |