#ifdef _WIN32
#define _CRT_SECURE_NO_WARNINGS
#endif

#include <time.h>
#include <stdio.h>
#include <stdlib.h>

int main(void)
{
	int ret = 0;
	const char *months[] = { "Jan", "Feb", "Mar", "April", "May", "June", "July", "Aug", "Sep", "Oct", "Nov", "Dec" };
	const char *days[] = { "Sun", "Mon", "Tue", "Wed", "Tur", "Fri", "Sat" };

	/* DST switch in April in first Sunday and October, last Sunday */
	putenv("TZ=EST5EDT,M4.1.0/02:00,M10.5.0/02:00");

	/* January, 1970, invalid input for tm_mday (0 instead 1..31) */
	/* non-normalized input for minutes: 1140/60 = 19, so 19:00 EST5EDT time, which is 5 hours before GMT, and should result in t == 0 below */
	/* let system figure out whether DST is effect */
	struct tm tmp = { 0, 1140, 0, 0, 0, 70, -858993460, -858993460, -1};

	printf("enter mktime with: %04d/%s/%02d %02d:%02d:%02d, week day: %d, year day: %d, dst: %d\n", 
				tmp.tm_year + 1900, months[tmp.tm_mon], tmp.tm_mday,
				tmp.tm_hour, tmp.tm_min, tmp.tm_sec, 
				tmp.tm_wday, tmp.tm_yday, tmp.tm_isdst);

	time_t t = olson_mktime(&tmp);

	/* expect: t == 0, DST is off, time is exactly at the boundary of lowest possible UTC value */
	printf("the return value of mktime is: %lld\n", (long long)t);
	printf("normalized times: %04d/%s/%02d %02d:%02d:%02d, week day: %s, year day: %d, dst: %d\n", 
				tmp.tm_year + 1900, months[tmp.tm_mon], tmp.tm_mday,
				tmp.tm_hour, tmp.tm_min, tmp.tm_sec, 
				days[tmp.tm_wday], tmp.tm_yday, tmp.tm_isdst);

	if (t >= 0) {
		printf("tz=%s, %s\n", tzname[0], tzname[1]);
	}

	return 0;
}