/* mktime.c (emx+gcc) -- Copyright (c) 1990-1993 by Eberhard Mattes */

#include <sys/emx.h>
#include <time.h>

time_t mktime (struct tm *t)
{
  time_t x;
  struct tm *tmp;

  if (!_tzset_flag) tzset ();
  if (t->tm_sec < 0 || t->tm_min < 0 || t->tm_hour < 0
      || t->tm_mday < 0 || t->tm_mon < 0 || t->tm_year < 0)
    return ((time_t)(-1));
  if (t->tm_mon >= 12)
    {
      t->tm_year += (t->tm_mon / 12);
      t->tm_mon %= 12;        /* _mktime wants 0 <= tm_mon <= 11 */
    }
  x = (time_t)_mktime (t) + timezone;
  tmp = localtime (&x);
  if (tmp == NULL)
    return ((time_t)(-1));
  else
    *t = *tmp;
  return (x);
}


/* year >= 1582, 1 <= month <= 12, 1 <= day <= 31 */
/* source: emclib */

int _day (int year, int month, int day)
{
  int result;

  if (year < 1582)
    return (-1);
  result = 365 * year + day + 31 * (month - 1);
  if (month <= 2)
    --year;
  else
    result -= (4 * month + 23) / 10;
  result += year / 4 - (3 * (year / 100 + 1)) / 4;
  return (result);
}


int _mktime (struct tm *t)
{
  int result;

  result = _day (t->tm_year+1900, t->tm_mon+1, t->tm_mday);
  if (result < 0)
    return (-1);
  result -= 719528;           /* day (1970, 1, 1); */
  result *= 24*60*60;
  result += t->tm_sec + 60*t->tm_min + 60*60*t->tm_hour;
  return (result);
}