StdLib/LibC/Time/tzfile.h

   1 /** @file
   2     Time Zone processing, declarations and macros.
   3
   4   Copyright (c) 2010, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials are licensed and made available under
   6   the terms and conditions of the BSD License that accompanies this distribution.
   7   The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php.
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13   Derived from the NIH time zone package file, tzfile.h, which contains the following notice:
  14
  15     This file is in the public domain, so clarified as of
  16     1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov).
  17
  18     This header is for use ONLY with the time conversion code.
  19     There is no guarantee that it will remain unchanged,
  20     or that it will remain at all.
  21     Do NOT copy it to any system include directory.
  22     Thank you!
  23
  24     NetBSD: tzfile.h,v 1.8 1998/01/22 07:06:59 jtc Exp
  25 **/
  26 #ifndef TZFILE_H
  27 #define TZFILE_H
  28
  29 /*
  30 ** Information about time zone files.
  31 */
  32
  33 #ifndef TZDIR   /* Time zone object file directory */
  34 #define TZDIR   "/usr/share/zoneinfo"
  35 #endif /* !defined TZDIR */
  36
  37 #ifndef TZDEFAULT
  38 #define TZDEFAULT "/etc/localtime"
  39 #endif /* !defined TZDEFAULT */
  40
  41 #ifndef TZDEFRULES
  42 #define TZDEFRULES  "posixrules"
  43 #endif /* !defined TZDEFRULES */
  44
  45 /*
  46 ** Each file begins with. . .
  47 */
  48
  49 #define TZ_MAGIC  "TZif"
  50
  51 struct tzhead {
  52   char  tzh_magic[4];   /* TZ_MAGIC */
  53   char  tzh_reserved[16]; /* reserved for future use */
  54   char  tzh_ttisgmtcnt[4];  /* coded number of trans. time flags */
  55   char  tzh_ttisstdcnt[4];  /* coded number of trans. time flags */
  56   char  tzh_leapcnt[4];   /* coded number of leap seconds */
  57   char  tzh_timecnt[4];   /* coded number of transition times */
  58   char  tzh_typecnt[4];   /* coded number of local time types */
  59   char  tzh_charcnt[4];   /* coded number of abbr. chars */
  60 };
  61
  62 /*
  63 ** . . .followed by. . .
  64 **
  65 **  tzh_timecnt (char [4])s   coded transition times a la time(2)
  66 **  tzh_timecnt (unsigned char)s  types of local time starting at above
  67 **  tzh_typecnt repetitions of
  68 **    one (char [4])    coded UTC offset in seconds
  69 **    one (unsigned char) used to set tm_isdst
  70 **    one (unsigned char) that's an abbreviation list index
  71 **  tzh_charcnt (char)s   '\0'-terminated zone abbreviations
  72 **  tzh_leapcnt repetitions of
  73 **    one (char [4])    coded leap second transition times
  74 **    one (char [4])    total correction after above
  75 **  tzh_ttisstdcnt (char)s    indexed by type; if TRUE, transition
  76 **          time is standard time, if FALSE,
  77 **          transition time is wall clock time
  78 **          if absent, transition times are
  79 **          assumed to be wall clock time
  80 **  tzh_ttisgmtcnt (char)s    indexed by type; if TRUE, transition
  81 **          time is UTC, if FALSE,
  82 **          transition time is local time
  83 **          if absent, transition times are
  84 **          assumed to be local time
  85 */
  86
  87 /*
  88 ** In the current implementation, "tzset()" refuses to deal with files that
  89 ** exceed any of the limits below.
  90 */
  91
  92 #ifndef TZ_MAX_TIMES
  93 /*
  94 ** The TZ_MAX_TIMES value below is enough to handle a bit more than a
  95 ** year's worth of solar time (corrected daily to the nearest second) or
  96 ** 138 years of Pacific Presidential Election time
  97 ** (where there are three time zone transitions every fourth year).
  98 */
  99 #define TZ_MAX_TIMES  370
 100 #endif /* !defined TZ_MAX_TIMES */
 101
 102 #ifndef TZ_MAX_TYPES
 103 #ifndef NOSOLAR
 104 #define TZ_MAX_TYPES  256 /* Limited by what (unsigned char)'s can hold */
 105 #endif /* !defined NOSOLAR */
 106 #ifdef NOSOLAR
 107 /*
 108 ** Must be at least 14 for Europe/Riga as of Jan 12 1995,
 109 ** as noted by Earl Chew <earl@hpato.aus.hp.com>.
 110 */
 111 #define TZ_MAX_TYPES  20  /* Maximum number of local time types */
 112 #endif /* !defined NOSOLAR */
 113 #endif /* !defined TZ_MAX_TYPES */
 114
 115 #ifndef TZ_MAX_CHARS
 116 #define TZ_MAX_CHARS  50  /* Maximum number of abbreviation characters */
 117         /* (limited by what unsigned chars can hold) */
 118 #endif /* !defined TZ_MAX_CHARS */
 119
 120 #ifndef TZ_MAX_LEAPS
 121 #define TZ_MAX_LEAPS  50  /* Maximum number of leap second corrections */
 122 #endif /* !defined TZ_MAX_LEAPS */
 123
 124 #define SECSPERMIN  60
 125 #define MINSPERHOUR 60
 126 #define HOURSPERDAY 24
 127 #define DAYSPERWEEK 7
 128 #define DAYSPERNYEAR  365
 129 #define DAYSPERLYEAR  366
 130 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
 131 #define SECSPERDAY  ((LONG32)(SECSPERHOUR * HOURSPERDAY))
 132 #define MONSPERYEAR 12
 133
 134 #define TM_SUNDAY 0
 135 #define TM_MONDAY 1
 136 #define TM_TUESDAY  2
 137 #define TM_WEDNESDAY  3
 138 #define TM_THURSDAY 4
 139 #define TM_FRIDAY 5
 140 #define TM_SATURDAY 6
 141
 142 #define TM_JANUARY  0
 143 #define TM_FEBRUARY 1
 144 #define TM_MARCH  2
 145 #define TM_APRIL  3
 146 #define TM_MAY    4
 147 #define TM_JUNE   5
 148 #define TM_JULY   6
 149 #define TM_AUGUST 7
 150 #define TM_SEPTEMBER  8
 151 #define TM_OCTOBER  9
 152 #define TM_NOVEMBER 10
 153 #define TM_DECEMBER 11
 154
 155 #define TM_YEAR_BASE  1900
 156
 157 #define EPOCH_YEAR  1970
 158 #define EPOCH_WDAY  TM_THURSDAY   // Use this for 32-bit time_t
 159 //#define EPOCH_WDAY  TM_SUNDAY     // Use this for 64-bit time_t
 160
 161 /*
 162 ** Accurate only for the past couple of centuries;
 163 ** that will probably do.
 164 */
 165
 166 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
 167
 168 #endif /* !defined TZFILE_H */