xref: /netbsd-src/include/tzfile.h (revision 8a8f936f250a330d54f8a24ed0e92aadf9743a7b)
1 /*	$NetBSD: tzfile.h,v 1.6 1998/07/30 14:11:22 kleink Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Arthur David Olson of the National Cancer Institute.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)tzfile.h	8.1 (Berkeley) 6/2/93
39  */
40 
41 #ifndef _TZFILE_H_
42 #define	_TZFILE_H_
43 
44 /*
45  * Information about time zone files.
46  */
47 			/* Time zone object file directory */
48 #define TZDIR		"/usr/share/zoneinfo"
49 #define TZDEFAULT	"/etc/localtime"
50 #define TZDEFRULES	"posixrules"
51 
52 /*
53 ** Each file begins with. . .
54 */
55 
56 #define TZ_MAGIC	"TZif"
57 
58 struct tzhead {
59 	char	tzh_magic[4];		/* TZ_MAGIC */
60 	char	tzh_reserved[16];	/* reserved for future use */
61 	char	tzh_ttisgmtcnt[4];	/* coded number of trans. time flags */
62 	char	tzh_ttisstdcnt[4];	/* coded number of trans. time flags */
63 	char	tzh_leapcnt[4];		/* coded number of leap seconds */
64 	char	tzh_timecnt[4];		/* coded number of transition times */
65 	char	tzh_typecnt[4];		/* coded number of local time types */
66 	char	tzh_charcnt[4];		/* coded number of abbr. chars */
67 };
68 
69 /*
70 ** . . .followed by. . .
71 **
72 **	tzh_timecnt (char [4])s		coded transition times a la time(2)
73 **	tzh_timecnt (unsigned char)s	types of local time starting at above
74 **	tzh_typecnt repetitions of
75 **		one (char [4])		coded UTC offset in seconds
76 **		one (unsigned char)	used to set tm_isdst
77 **		one (unsigned char)	that's an abbreviation list index
78 **	tzh_charcnt (char)s		'\0'-terminated zone abbreviations
79 **	tzh_leapcnt repetitions of
80 **		one (char [4])		coded leap second transition times
81 **		one (char [4])		total correction after above
82 **	tzh_ttisstdcnt (char)s		indexed by type; if TRUE, transition
83 **					time is standard time, if FALSE,
84 **					transition time is wall clock time
85 **					if absent, transition times are
86 **					assumed to be wall clock time
87 **	tzh_ttisgmtcnt (char)s		indexed by type; if TRUE, transition
88 **					time is UTC, if FALSE,
89 **					transition time is wall clock time
90 **					if absent, transition times are
91 **					assumed to be local time
92 */
93 
94 /*
95 ** In the current implementation, "tzset()" refuses to deal with files that
96 ** exceed any of the limits below.
97 */
98 
99 /*
100 ** The TZ_MAX_TIMES value below is enough to handle a bit more than a
101 ** year's worth of solar time (corrected daily to the nearest second) or
102 ** 138 years of Pacific Presidential Election time
103 ** (where there are three time zone transitions every fourth year).
104 */
105 #define TZ_MAX_TIMES	370
106 
107 #define NOSOLAR			/* 4BSD doesn't currently handle solar time */
108 
109 #ifndef NOSOLAR
110 #define TZ_MAX_TYPES	256	/* Limited by what (unsigned char)'s can hold */
111 #else
112 #define TZ_MAX_TYPES	10	/* Maximum number of local time types */
113 #endif
114 
115 #define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */
116 
117 #define	TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */
118 
119 #define SECSPERMIN	60
120 #define MINSPERHOUR	60
121 #define HOURSPERDAY	24
122 #define DAYSPERWEEK	7
123 #define DAYSPERNYEAR	365
124 #define DAYSPERLYEAR	366
125 #define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
126 #define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
127 #define MONSPERYEAR	12
128 
129 #define TM_SUNDAY	0
130 #define TM_MONDAY	1
131 #define TM_TUESDAY	2
132 #define TM_WEDNESDAY	3
133 #define TM_THURSDAY	4
134 #define TM_FRIDAY	5
135 #define TM_SATURDAY	6
136 
137 #define TM_JANUARY	0
138 #define TM_FEBRUARY	1
139 #define TM_MARCH	2
140 #define TM_APRIL	3
141 #define TM_MAY		4
142 #define TM_JUNE		5
143 #define TM_JULY		6
144 #define TM_AUGUST	7
145 #define TM_SEPTEMBER	8
146 #define TM_OCTOBER	9
147 #define TM_NOVEMBER	10
148 #define TM_DECEMBER	11
149 
150 #define TM_YEAR_BASE	1900
151 
152 #define EPOCH_YEAR	1970
153 #define EPOCH_WDAY	TM_THURSDAY
154 
155 /*
156 ** Accurate only for the past couple of centuries;
157 ** that will probably do.
158 */
159 
160 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
161 
162 #endif /* !_TZFILE_H_ */
163