Find a DST (Summer Time) timestamp using Objective-C / C?

Is there a way to get a specific date (path) when daytime buttocks for each country begin and end using C or Objective-C?

In Mexico, daylight saving time begins on the first Sunday of April at 2 a.m. and ends on the last Sunday of October at 2 a.m. On many POSIX systems, this is written as

M4.1.0/2,M10.5.0/2
(Begins: Month 4, 1st Sunday at 02:00AM, Ends: Month 10, last Sunday at 02:00AM)

I know that you can find out if summer savings are active by using

NSTimeZone* systemTimeZone = [NSTimeZone systemTimeZone];
BOOL dstIsOn = [systemTimeZone isDaylightSavingTime];

and that you can get the time until the next one Daylight Savingsbegins

NSTimeZone* systemTimeZone = [NSTimeZone systemTimeZone];
NSTimeInterval delta = [systemTimeZone daylightSavingTimeOffset];

BUT: How can I find a specific day when daylight saving time starts / ends?

Is there any killer table that I could not find?

Any help would be greatly appreciated!