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/* This code placed in the public domain by Mark W. Eichin */
#include <stdio.h>
#include "k5-int.h"
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#ifdef TIME_WITH_SYS_TIME
#include <time.h>
#endif
#else
#include <time.h>
#endif
/* take a struct tm, return seconds from GMT epoch */
/* like mktime, this ignores tm_wday and tm_yday. */
/* unlike mktime, this does not set them... it only passes a return value. */
static const days_in_month[12] = {
0, /* jan 31 */
31, /* feb 28 */
59, /* mar 31 */
90, /* apr 30 */
120, /* may 31 */
151, /* jun 30 */
181, /* jul 31 */
212, /* aug 31 */
243, /* sep 30 */
273, /* oct 31 */
304, /* nov 30 */
334 /* dec 31 */
};
#define hasleapday(year) (year%400?(year%100?(year%4?0:1):0):1)
time_t gmt_mktime(t)
struct tm* t;
{
time_t accum;
#define assert_time(cnd) if(!(cnd)) return (time_t) -1
assert_time(t->tm_year>=70);
assert_time(t->tm_year<=138);
assert_time(t->tm_mon>=0);
assert_time(t->tm_mon<=11);
assert_time(t->tm_mday>=1);
assert_time(t->tm_mday<=31);
assert_time(t->tm_hour>=0);
assert_time(t->tm_hour<=23);
assert_time(t->tm_min>=0);
assert_time(t->tm_min<=59);
assert_time(t->tm_sec>=0);
assert_time(t->tm_sec<=62);
#undef assert_time
accum = t->tm_year - 70;
accum *= 365; /* 365 days/normal year */
/* add in leap day for all previous years */
accum += (t->tm_year - 69) / 4;
/* add in leap day for this year */
if(t->tm_mon >= 2) /* march or later */
if(hasleapday((t->tm_year + 1900))) accum += 1;
accum += days_in_month[t->tm_mon];
accum += t->tm_mday-1; /* days of month are the only 1-based field */
accum *= 24; /* 24 hour/day */
accum += t->tm_hour;
accum *= 60; /* 60 minute/hour */
accum += t->tm_min;
accum *= 60; /* 60 seconds/minute */
accum += t->tm_sec;
return accum;
}
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