luxos/Kernel/library/time.c

#include <time.h>
extern volatile TimeSystem _internal_time;
extern uint32 _internal_frequency_hz;

// Length of months (summed)
const int16 MonthLen[] = {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };


TimeSystem ConvertTimeToTimeSystem (Time t)
{
	TimeSystem sys = {0,0};
	
	t.Year--; t.Month--; t.Day--; t.WeekDay--;

	sys.Time = (uint32)(t.Hour * 3600000) + (uint32)(t.Minute * 60000) + (uint32)(t.Second * 1000) + (uint32)t.Milisecond;

	if (t.Year < 0) return sys;

	sys.Date = (uint32)(t.Day) + (uint32)(MonthLen[t.Month])
			+ (uint32)((t.Year/4) * (365*4 + 1)) + (uint32)(t.Year%4 * 365);
			
	return sys;
}

Time ConvertTimeSystemToTime (TimeSystem InternalTime)
{
	Time t;
	t.Milisecond = InternalTime.Time % 1000;
	t.Second = (InternalTime.Time / 1000) % 60;
	t.Minute = (InternalTime.Time / 60000) % 60;
	t.Hour = (InternalTime.Time / 3600000);

	
	uint32 DayOfYear = (InternalTime.Date % 1461) % 365;
	t.Year = (InternalTime.Date / 1461)*4 + (InternalTime.Date % 1461)/365 + 1;
	t.Month = 11;
	while ((int32)DayOfYear < (MonthLen[t.Month] + (t.Year % 4 == 0 && t.Month>1))) t.Month--;
	t.WeekDay = InternalTime.Date % 7;
	t.Day = DayOfYear - MonthLen[t.Month] - (t.Year % 4 == 0 && t.Month>1);

	t.Month++; t.WeekDay++; t.Day++;

	return t;
} 

uint16 TimeCalculateWeekday (Time t)
{
	t.Year--;
	uint32 d = (uint32)(t.Day-1) + (uint32)(MonthLen[t.Month-1]) +
			+ (uint32)((t.Year/4) * (365*4 + 1)) + (uint32)(t.Year%4 * 365);
			
	return 1 + (d%7);
}


TimeSystem TimeGetInternalTime()
{
	return _internal_time;
}

void TimeSetInternalTime(TimeSystem t)
{
	_internal_time = t;
}

uint32 TimeGetInternalFrequency ()
{
	return _internal_frequency_hz;
}

void TimeSetInternalFrequency (uint32 f)
{
	_internal_frequency_hz = f;
}


TimeSystem _timer;
#define MILISECONDS_IN_DAY 86400000

void TimerStart (uint32 ms)
{
	_timer = TimeGetInternalTime();
	_timer.Time += ms;

	if (_timer.Time >= MILISECONDS_IN_DAY)
		{
			_timer.Date++;
			_timer.Time-=MILISECONDS_IN_DAY;
		}
}

uint8 TimerIsDone ()
{
	TimeSystem now = TimeGetInternalTime();
	if (_timer.Date >= now.Date && _timer.Time > now.Time) return 0;

	return 1;
}