rtt-f030/components/libc/minilibc/time.c

227 lines
4.8 KiB
C

#include <time.h>
/* days per month -- nonleap! */
const short __spm[13] =
{ 0,
(31),
(31+28),
(31+28+31),
(31+28+31+30),
(31+28+31+30+31),
(31+28+31+30+31+30),
(31+28+31+30+31+30+31),
(31+28+31+30+31+30+31+31),
(31+28+31+30+31+30+31+31+30),
(31+28+31+30+31+30+31+31+30+31),
(31+28+31+30+31+30+31+31+30+31+30),
(31+28+31+30+31+30+31+31+30+31+30+31),
};
static long int timezone;
static const char days[] = "Sun Mon Tue Wed Thu Fri Sat ";
static const char months[] = "Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ";
/* seconds per day */
#define SPD 24*60*60
int __isleap(int year)
{
/* every fourth year is a leap year except for century years that are
* not divisible by 400. */
/* return (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)); */
return (!(year % 4) && ((year % 100) || !(year % 400)));
}
struct tm *gmtime_r(const time_t *timep, struct tm *r)
{
time_t i;
register time_t work = *timep % (SPD);
r->tm_sec = work % 60;
work /= 60;
r->tm_min = work % 60;
r->tm_hour = work / 60;
work = *timep / (SPD);
r->tm_wday = (4 + work) % 7;
for (i = 1970;; ++i)
{
register time_t k = __isleap(i) ? 366 : 365;
if (work >= k)
work -= k;
else
break;
}
r->tm_year = i - 1900;
r->tm_yday = work;
r->tm_mday = 1;
if (__isleap(i) && (work > 58))
{
if (work == 59)
r->tm_mday = 2; /* 29.2. */
work -= 1;
}
for (i = 11; i && (__spm[i] > work); --i)
;
r->tm_mon = i;
r->tm_mday += work - __spm[i];
return r;
}
struct tm* localtime_r(const time_t* t, struct tm* r)
{
time_t tmp;
struct timezone tz;
gettimeofday(0, &tz);
timezone = tz.tz_minuteswest * 60L;
tmp = *t + timezone;
return gmtime_r(&tmp, r);
}
struct tm* localtime(const time_t* t)
{
static struct tm tmp;
return localtime_r(t, &tmp);
}
time_t timegm(struct tm * const t)
{
register time_t day;
register time_t i;
register time_t years = t->tm_year - 70;
if (t->tm_sec > 60)
{
t->tm_min += t->tm_sec / 60;
t->tm_sec %= 60;
}
if (t->tm_min > 60)
{
t->tm_hour += t->tm_min / 60;
t->tm_min %= 60;
}
if (t->tm_hour > 24)
{
t->tm_mday += t->tm_hour / 24;
t->tm_hour %= 24;
}
if (t->tm_mon > 12)
{
t->tm_year += t->tm_mon / 12;
t->tm_mon %= 12;
}
while (t->tm_mday > __spm[1 + t->tm_mon])
{
if (t->tm_mon == 1 && __isleap(t->tm_year + 1900))
{
--t->tm_mday;
}
t->tm_mday -= __spm[t->tm_mon];
++t->tm_mon;
if (t->tm_mon > 11)
{
t->tm_mon = 0;
++t->tm_year;
}
}
if (t->tm_year < 70)
return (time_t) -1;
/* Days since 1970 is 365 * number of years + number of leap years since 1970 */
day = years * 365 + (years + 1) / 4;
/* After 2100 we have to substract 3 leap years for every 400 years
This is not intuitive. Most mktime implementations do not support
dates after 2059, anyway, so we might leave this out for it's
bloat. */
if ((years -= 131) >= 0)
{
years /= 100;
day -= (years >> 2) * 3 + 1;
if ((years &= 3) == 3)
years--;
day -= years;
}
day += t->tm_yday = __spm[t->tm_mon] + t->tm_mday - 1 +
(__isleap(t->tm_year + 1900) & (t->tm_mon > 1));
/* day is now the number of days since 'Jan 1 1970' */
i = 7;
t->tm_wday = (day + 4) % i; /* Sunday=0, Monday=1, ..., Saturday=6 */
i = 24;
day *= i;
i = 60;
return ((day + t->tm_hour) * i + t->tm_min) * i + t->tm_sec;
}
time_t mktime(register struct tm* const t)
{
time_t x = timegm(t);
struct timezone tz;
gettimeofday(0, &tz);
timezone = tz.tz_minuteswest * 60L;
x += timezone;
return x;
}
static void num2str(char *c, int i)
{
c[0] = i / 10 + '0';
c[1] = i % 10 + '0';
}
char *asctime_r(const struct tm *t, char *buf)
{
/* "Wed Jun 30 21:49:08 1993\n" */
*(int*) buf = *(int*) (days + (t->tm_wday << 2));
*(int*) (buf + 4) = *(int*) (months + (t->tm_mon << 2));
num2str(buf + 8, t->tm_mday);
if (buf[8] == '0')
buf[8] = ' ';
buf[10] = ' ';
num2str(buf + 11, t->tm_hour);
buf[13] = ':';
num2str(buf + 14, t->tm_min);
buf[16] = ':';
num2str(buf + 17, t->tm_sec);
buf[19] = ' ';
num2str(buf + 20, (t->tm_year + 1900) / 100);
num2str(buf + 22, (t->tm_year + 1900) % 100);
buf[24] = '\n';
return buf;
}
char *asctime(const struct tm *timeptr)
{
static char buf[25];
return asctime_r(timeptr, buf);
}
char *ctime(const time_t *timep)
{
return asctime(localtime(timep));
}
int gettimeofday(struct timeval *tp, void *ignore)
{
time_t time;
rt_device_t device;
device = rt_device_find("rtc");
if (device != RT_NULL)
{
rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time);
if (tp != RT_NULL)
{
tp->tv_sec = time;
tp->tv_usec = 0;
}
return time;
}
return 0;
}