hwclock: make it report system/rtc clock difference
function old new delta rtc_tm2time - 89 +89 read_rtc 23 86 +63 rtc_read_tm - 49 +49 hwclock_main 428 466 +38 rtcwake_main 453 477 +24 rtc_read_time 142 - -142 ------------------------------------------------------------------------------ (add/remove: 2/1 grow/shrink: 3/0 up/down: 263/-142) Total: 121 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
parent
695fa51c80
commit
5e3b14069e
@ -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
|
||||
|
18
libbb/rtc.c
18
libbb/rtc.c
@ -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");
|
||||
|
@ -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
|
||||
|
@ -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)
|
||||
|
Loading…
Reference in New Issue
Block a user