#include <sys/time.h>

time_t	datetime2unix(datetime_t *datetime){
	time_t result = 0;
	
	int schaltjahre = ((datetime->year - 1) - 1968)/4
					- ((datetime->year - 1) - 1900)/100
					+ ((datetime->year - 1) - 1600)/400;
	
	int tage1970 = ((datetime->year - 1970) * 365) + schaltjahre + daysfromyearstart(datetime->month) + datetime->day;
	
	if ( (datetime->month>1) && ((datetime->year%4==0) && ((datetime->year%100!=0) || (datetime->year%400==0)))){
		tage1970++;
	};
	
	result = datetime->second + (60L * (datetime->minute + 60L * (datetime->hour + (24L * tage1970))));
	
	return result;
};