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[glibc/history.git] / timezone / tzfile.h
blob0921c3c3396e8116ff749f3c8116011d09e00202
1 #ifndef TZFILE_H
3 #define TZFILE_H
5 /*
6 ** This file is in the public domain, so clarified as of
7 ** 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov).
8 */
11 ** This header is for use ONLY with the time conversion code.
12 ** There is no guarantee that it will remain unchanged,
13 ** or that it will remain at all.
14 ** Do NOT copy it to any system include directory.
15 ** Thank you!
19 ** ID
22 #ifndef lint
23 #ifndef NOID
24 static char tzfilehid[] = "@(#)tzfile.h 7.14";
25 #endif /* !defined NOID */
26 #endif /* !defined lint */
29 ** Information about time zone files.
32 #ifndef TZDIR
33 #define TZDIR "/usr/local/etc/zoneinfo" /* Time zone object file directory */
34 #endif /* !defined TZDIR */
36 #ifndef TZDEFAULT
37 #define TZDEFAULT "localtime"
38 #endif /* !defined TZDEFAULT */
40 #ifndef TZDEFRULES
41 #define TZDEFRULES "posixrules"
42 #endif /* !defined TZDEFRULES */
45 ** Each file begins with. . .
48 #define TZ_MAGIC "TZif"
50 struct tzhead {
51 char tzh_magic[4]; /* TZ_MAGIC */
52 char tzh_reserved[16]; /* reserved for future use */
53 char tzh_ttisgmtcnt[4]; /* coded number of trans. time flags */
54 char tzh_ttisstdcnt[4]; /* coded number of trans. time flags */
55 char tzh_leapcnt[4]; /* coded number of leap seconds */
56 char tzh_timecnt[4]; /* coded number of transition times */
57 char tzh_typecnt[4]; /* coded number of local time types */
58 char tzh_charcnt[4]; /* coded number of abbr. chars */
62 ** . . .followed by. . .
64 ** tzh_timecnt (char [4])s coded transition times a la time(2)
65 ** tzh_timecnt (unsigned char)s types of local time starting at above
66 ** tzh_typecnt repetitions of
67 ** one (char [4]) coded UTC offset in seconds
68 ** one (unsigned char) used to set tm_isdst
69 ** one (unsigned char) that's an abbreviation list index
70 ** tzh_charcnt (char)s '\0'-terminated zone abbreviations
71 ** tzh_leapcnt repetitions of
72 ** one (char [4]) coded leap second transition times
73 ** one (char [4]) total correction after above
74 ** tzh_ttisstdcnt (char)s indexed by type; if TRUE, transition
75 ** time is standard time, if FALSE,
76 ** transition time is wall clock time
77 ** if absent, transition times are
78 ** assumed to be wall clock time
79 ** tzh_ttisgmtcnt (char)s indexed by type; if TRUE, transition
80 ** time is UTC, if FALSE,
81 ** transition time is local time
82 ** if absent, transition times are
83 ** assumed to be local time
87 ** In the current implementation, "tzset()" refuses to deal with files that
88 ** exceed any of the limits below.
91 #ifndef TZ_MAX_TIMES
93 ** The TZ_MAX_TIMES value below is enough to handle a bit more than a
94 ** year's worth of solar time (corrected daily to the nearest second) or
95 ** 138 years of Pacific Presidential Election time
96 ** (where there are three time zone transitions every fourth year).
98 #define TZ_MAX_TIMES 370
99 #endif /* !defined TZ_MAX_TIMES */
101 #ifndef TZ_MAX_TYPES
102 #ifndef NOSOLAR
103 #define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */
104 #endif /* !defined NOSOLAR */
105 #ifdef NOSOLAR
107 ** Must be at least 14 for Europe/Riga as of Jan 12 1995,
108 ** as noted by Earl Chew <earl@hpato.aus.hp.com>.
110 #define TZ_MAX_TYPES 20 /* Maximum number of local time types */
111 #endif /* !defined NOSOLAR */
112 #endif /* !defined TZ_MAX_TYPES */
114 #ifndef TZ_MAX_CHARS
115 #define TZ_MAX_CHARS 50 /* Maximum number of abbreviation characters */
116 /* (limited by what unsigned chars can hold) */
117 #endif /* !defined TZ_MAX_CHARS */
119 #ifndef TZ_MAX_LEAPS
120 #define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */
121 #endif /* !defined TZ_MAX_LEAPS */
123 #define SECSPERMIN 60
124 #define MINSPERHOUR 60
125 #define HOURSPERDAY 24
126 #define DAYSPERWEEK 7
127 #define DAYSPERNYEAR 365
128 #define DAYSPERLYEAR 366
129 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
130 #define SECSPERDAY ((long) SECSPERHOUR * HOURSPERDAY)
131 #define MONSPERYEAR 12
133 #define TM_SUNDAY 0
134 #define TM_MONDAY 1
135 #define TM_TUESDAY 2
136 #define TM_WEDNESDAY 3
137 #define TM_THURSDAY 4
138 #define TM_FRIDAY 5
139 #define TM_SATURDAY 6
141 #define TM_JANUARY 0
142 #define TM_FEBRUARY 1
143 #define TM_MARCH 2
144 #define TM_APRIL 3
145 #define TM_MAY 4
146 #define TM_JUNE 5
147 #define TM_JULY 6
148 #define TM_AUGUST 7
149 #define TM_SEPTEMBER 8
150 #define TM_OCTOBER 9
151 #define TM_NOVEMBER 10
152 #define TM_DECEMBER 11
154 #define TM_YEAR_BASE 1900
156 #define EPOCH_YEAR 1970
157 #define EPOCH_WDAY TM_THURSDAY
160 ** Accurate only for the past couple of centuries;
161 ** that will probably do.
164 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
166 #ifndef USG
169 ** Use of the underscored variants may cause problems if you move your code to
170 ** certain System-V-based systems; for maximum portability, use the
171 ** underscore-free variants. The underscored variants are provided for
172 ** backward compatibility only; they may disappear from future versions of
173 ** this file.
176 #define SECS_PER_MIN SECSPERMIN
177 #define MINS_PER_HOUR MINSPERHOUR
178 #define HOURS_PER_DAY HOURSPERDAY
179 #define DAYS_PER_WEEK DAYSPERWEEK
180 #define DAYS_PER_NYEAR DAYSPERNYEAR
181 #define DAYS_PER_LYEAR DAYSPERLYEAR
182 #define SECS_PER_HOUR SECSPERHOUR
183 #define SECS_PER_DAY SECSPERDAY
184 #define MONS_PER_YEAR MONSPERYEAR
186 #endif /* !defined USG */
188 #endif /* !defined TZFILE_H */