lib/sdk/crt/include/internal/time.h

   1 #define DIFFTIME 0x19db1ded53e8000ULL
   2 #define DIFFDAYS (3 * DAYSPER100YEARS + 17 * DAYSPER4YEARS + 1 * DAYSPERYEAR)
   3
   4 #define DAYSPERYEAR 365
   5 #define DAYSPER4YEARS (4*DAYSPERYEAR+1)
   6 #define DAYSPER100YEARS (25*DAYSPER4YEARS-1)
   7 #define DAYSPER400YEARS (4*DAYSPER100YEARS+1)
   8 #define SECONDSPERDAY (24*60*60)
   9 #define SECONDSPERHOUR (60*60)
  10 #define LEAPDAY 59
  11
  12 static __inline
  13 time_t
  14 FileTimeToUnixTime(const FILETIME *FileTime, USHORT *millitm)
  15 {
  16     ULARGE_INTEGER ULargeInt;
  17     time_t time;
  18
  19     ULargeInt.LowPart = FileTime->dwLowDateTime;
  20     ULargeInt.HighPart = FileTime->dwHighDateTime;
  21     ULargeInt.QuadPart -= DIFFTIME;
  22
  23     time = ULargeInt.QuadPart / 10000000;
  24     if (millitm)
  25         *millitm = (ULargeInt.QuadPart % 10000000) / 10000;
  26
  27     return time;
  28 }
  29
  30 static __inline
  31 long leapyears_passed(long days)
  32 {
  33     long quadcenturies, centuries, quadyears;
  34     quadcenturies = days / DAYSPER400YEARS;
  35     days -= quadcenturies;
  36     centuries = days / DAYSPER100YEARS;
  37     days += centuries;
  38     quadyears = days / DAYSPER4YEARS;
  39     return quadyears - centuries + quadcenturies;
  40 }
  41
  42 static __inline
  43 long leapdays_passed(long days)
  44 {
  45     return leapyears_passed(days + DAYSPERYEAR - LEAPDAY + 1);
  46 }
  47
  48 static __inline
  49 long years_passed(long days)
  50 {
  51     return (days - leapdays_passed(days)) / 365;
  52 }
  53
  54 extern long dst_begin;
  55 extern long dst_end;