5e3b14069
Denys Vlasenko
2010-01-06
Subject
hwclock: make it report system/rtc clock difference
Binary
No binary (build failed)
Architecture & Compiler Flags
—
Build Log
(log yok)
Commit Diff GitHub →
include/rtc_.h+5 -3
| @@ -11,9 +11,11 @@ | |
| PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN | |
| - | extern int rtc_adjtime_is_utc(void) FAST_FUNC; |
| - | extern int rtc_xopen(const char **default_rtc, int flags) FAST_FUNC; |
| - | extern time_t rtc_read_time(int fd, int utc) FAST_FUNC; |
| + | int rtc_adjtime_is_utc(void) FAST_FUNC; |
| + | int rtc_xopen(const char **default_rtc, int flags) FAST_FUNC; |
| + | void rtc_read_tm(struct tm *tm, int fd) FAST_FUNC; |
| + | time_t rtc_tm2time(struct tm *tm, int utc) FAST_FUNC; |
| + | |
| /* | |
| * Everything below this point has been copied from linux/rtc.h | |
libbb/rtc.c+10 -8
| @@ -59,15 +59,17 @@ int FAST_FUNC rtc_xopen(const char **default_rtc, int flags) | |
| return xopen(*default_rtc, flags); | |
| } | |
| - | time_t FAST_FUNC rtc_read_time(int fd, int utc) |
| + | void FAST_FUNC rtc_read_tm(struct tm *tm, int fd) |
| { | |
| - | struct tm tm; |
| - | char *oldtz = 0; |
| - | time_t t = 0; |
| + | memset(tm, 0, sizeof(*tm)); |
| + | xioctl(fd, RTC_RD_TIME, tm); |
| + | tm->tm_isdst = -1; /* "not known" */ |
| + | } |
| - | memset(&tm, 0, sizeof(struct tm)); |
| - | xioctl(fd, RTC_RD_TIME, &tm); |
| - | tm.tm_isdst = -1; /* not known */ |
| + | time_t FAST_FUNC rtc_tm2time(struct tm *tm, int utc) |
| + | { |
| + | char *oldtz = oldtz; /* for compiler */ |
| + | time_t t; |
| if (utc) { | |
| oldtz = getenv("TZ"); | |
| @@ -75,7 +77,7 @@ time_t FAST_FUNC rtc_read_time(int fd, int utc) | |
| tzset(); | |
| } | |
| - | t = mktime(&tm); |
| + | t = mktime(tm); |
| if (utc) { | |
| unsetenv("TZ"); | |
util-linux/hwclock.c+32 -12
| @@ -20,34 +20,54 @@ | |
| static const char *rtcname; | |
| - | static time_t read_rtc(int utc) |
| + | static time_t read_rtc(struct timeval *sys_tv, int utc) |
| { | |
| - | time_t ret; |
| + | struct tm tm; |
| int fd; | |
| + | int before; |
| fd = rtc_xopen(&rtcname, O_RDONLY); | |
| - | ret = rtc_read_time(fd, utc); |
| + | |
| + | rtc_read_tm(&tm, fd); |
| + | before = tm.tm_sec; |
| + | while (1) { |
| + | rtc_read_tm(&tm, fd); |
| + | gettimeofday(sys_tv, NULL); |
| + | if (before != tm.tm_sec) |
| + | break; |
| + | } |
| + | |
| if (ENABLE_FEATURE_CLEAN_UP) | |
| close(fd); | |
| - | return ret; |
| + | return rtc_tm2time(&tm, utc); |
| } | |
| static void show_clock(int utc) | |
| { | |
| - | //struct tm *ptm; |
| + | struct timeval sys_tv; |
| time_t t; | |
| + | long diff; |
| char *cp; | |
| - | t = read_rtc(utc); |
| - | //ptm = localtime(&t); /* Sets 'tzname[]' */ |
| + | t = read_rtc(&sys_tv, utc); |
| cp = ctime(&t); | |
| strchrnul(cp, '\n')[0] = '\0'; | |
| //printf("%s 0.000000 seconds %s\n", cp, utc ? "" : (ptm->tm_isdst ? tzname[1] : tzname[0])); | |
| - | /* 0.000000 stand for unimplemented difference between RTC and system clock */ |
| - | printf("%s 0.000000 seconds\n", cp); |
| + | diff = sys_tv.tv_sec - t; |
| + | if (diff < 0 /*&& tv.tv_usec != 0*/) { |
| + | /* Why? */ |
| + | /* diff >= 0 is ok: diff < 0, can't just use tv.tv_usec: */ |
| + | /* 45.520820 43.520820 */ |
| + | /* - 44.000000 - 45.000000 */ |
| + | /* = 0.520820 = -1.479180, not -2.520820! */ |
| + | diff++; |
| + | /* should be 1000000 - tv.tv_usec, but then we must check tv.tv_usec != 0 */ |
| + | sys_tv.tv_usec = 999999 - sys_tv.tv_usec; |
| + | } |
| + | printf("%s %ld.%06lu seconds\n", cp, diff, (unsigned long)sys_tv.tv_usec); |
| } | |
| static void to_sys_clock(int utc) | |
| @@ -58,7 +78,7 @@ static void to_sys_clock(int utc) | |
| tz.tz_minuteswest = timezone/60 - 60*daylight; | |
| tz.tz_dsttime = 0; | |
| - | tv.tv_sec = read_rtc(utc); |
| + | tv.tv_sec = read_rtc(NULL, utc); |
| tv.tv_usec = 0; | |
| if (settimeofday(&tv, &tz)) | |
| bb_perror_msg_and_die("settimeofday() failed"); | |
| @@ -79,15 +99,15 @@ static void from_sys_clock(int utc) | |
| gettimeofday(&tv, NULL); | |
| + | t = tv.tv_sec; |
| rem_usec = 1000000 - tv.tv_usec; | |
| if (rem_usec < 1024) { | |
| /* Less than 1ms to next second. Good enough */ | |
| small_rem: | |
| - | tv.tv_sec++; |
| + | t++; |
| } | |
| /* Prepare tm */ | |
| - | t = tv.tv_sec; |
| if (utc) | |
| gmtime_r(&t, &tm); /* may read /etc/xxx (it takes time) */ | |
| else | |
util-linux/rtcwake.c+6 -1
| @@ -160,7 +160,12 @@ int rtcwake_main(int argc UNUSED_PARAM, char **argv) | |
| /* relative or absolute alarm time, normalized to time_t */ | |
| sys_time = time(NULL); | |
| - | rtc_time = rtc_read_time(fd, utc); |
| + | { |
| + | struct tm tm; |
| + | rtc_read_tm(&tm, fd); |
| + | rtc_time = rtc_tm2time(&tm, utc); |
| + | } |
| + | |
| if (alarm_time) { | |
| if (alarm_time < sys_time) | |