src/time.h

   1 ///
   2 /// \file       time.h
   3 ///             Time related conversion routines.
   4 ///             time_t is the POSIX time.
   5 ///             min1900_t is the minutes from Jan 1, 1900
   6 ///
   7
   8 /*
   9     Copyright (C) 2005-2013, Net Direct Inc. (http://www.netdirect.ca/)
  10
  11     This program is free software; you can redistribute it and/or modify
  12     it under the terms of the GNU General Public License as published by
  13     the Free Software Foundation; either version 2 of the License, or
  14     (at your option) any later version.
  15
  16     This program is distributed in the hope that it will be useful,
  17     but WITHOUT ANY WARRANTY; without even the implied warranty of
  18     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  19
  20     See the GNU General Public License in the COPYING file at the
  21     root directory of this project for more details.
  22 */
  23
  24 #ifndef __BARRY_TIME_H__
  25 #define __BARRY_TIME_H__
  26
  27 #include "dll.h"
  28 #include <sys/time.h>           // for struct timespec
  29 #include <time.h>
  30 #include <stdint.h>
  31
  32 //
  33 // Calculate the number of minutes between Jan 01, 1900 and Jan 01, 1970
  34 //
  35 // There are 17 leap years between 1900 and 1970
  36 //    (1969-1900) / 4 = 17.25
  37 //
  38 // 1900 itself is not a leap year (not divisible by 400)
  39 //
  40 #define DAY_MINUTES (24 * 60)
  41 #define YEAR_MINUTES (365 * DAY_MINUTES)
  42 #define LEAP_YEAR_COUNT ((1970-1901) / 4)
  43 #define YEAR_COUNT (1970 - 1900)
  44
  45 // therefore, the difference between standard C's time and min1900_t's
  46 // time in minutes:
  47 #define STDC_MIN1900_DIFF (YEAR_COUNT * YEAR_MINUTES + LEAP_YEAR_COUNT * DAY_MINUTES)
  48
  49 namespace Barry {
  50
  51 typedef long min1900_t;
  52
  53 BXEXPORT min1900_t time2min(time_t t);
  54 BXEXPORT time_t min2time(min1900_t m);
  55
  56 // FIXME - turn StaticTimeZone into a C typedef and wrap this in extern "C"
  57 // so the data can be used in both C and C++ libraries
  58 //
  59 // This is named StaticTimeZone since the time zone table is hard coded
  60 // in the library.  If you want to know what the device's idea of time zones
  61 // is, then extract the time zone database using the TimeZone record class.
  62 //
  63 // See also the TimeZones class, which unifies access to the static and
  64 // dynamic time zone tables in one class API.
  65 //
  66 struct BXEXPORT StaticTimeZone
  67 {
  68         uint16_t Code;
  69         signed short HourOffset;
  70         signed short MinOffset;
  71         const char *Name;
  72 };
  73
  74 // FIXME - put this somewhere for both C and C++
  75 #define STATIC_TIME_ZONE_CODE_ERR       0xffff
  76
  77 BXEXPORT const StaticTimeZone* GetStaticTimeZoneTable();
  78 BXEXPORT const StaticTimeZone* GetStaticTimeZone(uint16_t Code);
  79 BXEXPORT unsigned short GetStaticTimeZoneCode(signed short HourOffset,
  80         signed short MinOffset = 0);
  81
  82 // Message time conversion stuff
  83 BXEXPORT time_t DayToDate( uint16_t Day );
  84 BXEXPORT time_t Message2Time(uint16_t r_date, uint16_t r_time);
  85
  86 // Thread timeout creation
  87 BXEXPORT struct timespec* ThreadTimeout(int timeout_ms, struct timespec *spec);
  88
  89 // Utility functions
  90 BXEXPORT int DaysInMonth(struct tm &t);
  91
  92 } // namespace Barry
  93
  94 #endif
  95