1 /* $NetBSD: tzfile.h,v 1.8 1998/01/22 07:06:59 jtc Exp $ */
7 ** This file is in the public domain, so clarified as of
8 ** 1996-06-05 by Arthur David Olson.
12 ** This header is for use ONLY with the time conversion code.
13 ** There is no guarantee that it will remain unchanged,
14 ** or that it will remain at all.
15 ** Do NOT copy it to any system include directory.
26 static char tzfilehid
[] = "@(#)tzfile.h 8.1";
28 #endif /* !defined NOID */
29 #endif /* !defined lint */
32 ** Information about time zone files.
35 #ifndef TZDIR /* Time zone object file directory */
36 #define TZDIR "/usr/share/zoneinfo"
37 #endif /* !defined TZDIR */
40 #define TZDEFAULT "/etc/localtime"
41 #endif /* !defined TZDEFAULT */
44 #define TZDEFRULES "posixrules"
45 #endif /* !defined TZDEFRULES */
48 ** Each file begins with. . .
51 #define TZ_MAGIC "TZif"
54 char tzh_magic
[4]; /* TZ_MAGIC */
55 char tzh_version
[1]; /* '\0' or '2' as of 2005 */
56 char tzh_reserved
[15]; /* reserved--must be zero */
57 char tzh_ttisgmtcnt
[4]; /* coded number of trans. time flags */
58 char tzh_ttisstdcnt
[4]; /* coded number of trans. time flags */
59 char tzh_leapcnt
[4]; /* coded number of leap seconds */
60 char tzh_timecnt
[4]; /* coded number of transition times */
61 char tzh_typecnt
[4]; /* coded number of local time types */
62 char tzh_charcnt
[4]; /* coded number of abbr. chars */
66 ** . . .followed by. . .
68 ** tzh_timecnt (char [4])s coded transition times a la time(2)
69 ** tzh_timecnt (unsigned char)s types of local time starting at above
70 ** tzh_typecnt repetitions of
71 ** one (char [4]) coded UTC offset in seconds
72 ** one (unsigned char) used to set tm_isdst
73 ** one (unsigned char) that's an abbreviation list index
74 ** tzh_charcnt (char)s '\0'-terminated zone abbreviations
75 ** tzh_leapcnt repetitions of
76 ** one (char [4]) coded leap second transition times
77 ** one (char [4]) total correction after above
78 ** tzh_ttisstdcnt (char)s indexed by type; if TRUE, transition
79 ** time is standard time, if FALSE,
80 ** transition time is wall clock time
81 ** if absent, transition times are
82 ** assumed to be wall clock time
83 ** tzh_ttisgmtcnt (char)s indexed by type; if TRUE, transition
84 ** time is UTC, if FALSE,
85 ** transition time is local time
86 ** if absent, transition times are
87 ** assumed to be local time
91 ** If tzh_version is '2' or greater, the above is followed by a second instance
92 ** of tzhead and a second instance of the data in which each coded transition
93 ** time uses 8 rather than 4 chars,
94 ** then a POSIX-TZ-environment-variable-style string for use in handling
95 ** instants after the last transition time stored in the file
96 ** (with nothing between the newlines if there is no POSIX representation for
101 ** In the current implementation, "tzset()" refuses to deal with files that
102 ** exceed any of the limits below.
106 #define TZ_MAX_TIMES 1200
107 #endif /* !defined TZ_MAX_TIMES */
111 #define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */
112 #endif /* !defined NOSOLAR */
115 ** Must be at least 14 for Europe/Riga as of Jan 12 1995,
116 ** as noted by Earl Chew.
118 #define TZ_MAX_TYPES 20 /* Maximum number of local time types */
119 #endif /* !defined NOSOLAR */
120 #endif /* !defined TZ_MAX_TYPES */
123 #define TZ_MAX_CHARS 50 /* Maximum number of abbreviation characters */
124 /* (limited by what unsigned chars can hold) */
125 #endif /* !defined TZ_MAX_CHARS */
128 #define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */
129 #endif /* !defined TZ_MAX_LEAPS */
131 #define SECSPERMIN 60
132 #define MINSPERHOUR 60
133 #define HOURSPERDAY 24
134 #define DAYSPERWEEK 7
135 #define DAYSPERNYEAR 365
136 #define DAYSPERLYEAR 366
137 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
138 #define SECSPERDAY ((long) SECSPERHOUR * HOURSPERDAY)
139 #define MONSPERYEAR 12
144 #define TM_WEDNESDAY 3
145 #define TM_THURSDAY 4
147 #define TM_SATURDAY 6
150 #define TM_FEBRUARY 1
157 #define TM_SEPTEMBER 8
159 #define TM_NOVEMBER 10
160 #define TM_DECEMBER 11
162 #define TM_YEAR_BASE 1900
164 #define EPOCH_YEAR 1970
165 #define EPOCH_WDAY TM_THURSDAY
167 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
170 ** Since everything in isleap is modulo 400 (or a factor of 400), we know that
171 ** isleap(y) == isleap(y % 400)
173 ** isleap(a + b) == isleap((a + b) % 400)
175 ** isleap(a + b) == isleap(a % 400 + b % 400)
176 ** This is true even if % means modulo rather than Fortran remainder
177 ** (which is allowed by C89 but not C99).
178 ** We use this to avoid addition overflow problems.
181 #define isleap_sum(a, b) isleap((a) % 400 + (b) % 400)
183 #endif /* !defined TZFILE_H */