/* Returns the local timezone in seconds east of UTC for the time t,
* or for the current time if t is zero.
*/
time_t mutt_local_tz (time_t t)
{
struct tm *ptm;
struct tm utc;
if (!t)
t = time (NULL);
ptm = gmtime (&t);
/* need to make a copy because gmtime/localtime return a pointer to
static memory (grr!) */
memcpy (&utc, ptm, sizeof (utc));
return (compute_tz (t, &utc));
}
/* converts struct tm to time_t, but does not take the local timezone into
account unless ``local'' is nonzero */
time_t mutt_mktime(struct tm *t, int local)
{
time_t g;
static const int AccumDaysPerMonth[12] = {
0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
};
/* Compute the number of days since January 1 in the same year */
g = AccumDaysPerMonth[t->tm_mon % 12];
/* The leap years are 1972 and every 4. year until 2096,
* but this algorithm will fail after year 2099 */
g += t->tm_mday;
if ((t->tm_year % 4)
|| (t->tm_mon < 2))
g--;
t->tm_yday = g;
/* Compute the number of days since January 1, 1970 */
g += (t->tm_year - 70) * 365;
g += (t->tm_year - 69) / 4;
/* Compute the number of hours */
g *= 24;
g += t->tm_hour;
/* Compute the number of minutes */
g *= 60;
g += t->tm_min;
/* Compute the number of seconds */
g *= 60;
g += t->tm_sec;
if (local)
g -= compute_tz(g, t);
return g;
}
