xref: /netbsd-src/include/tzfile.h (revision 413d532bcc3f62d122e56d92e13ac64825a40baf)
1 /*	$NetBSD: tzfile.h,v 1.7 2003/08/07 09:44:11 agc 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. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)tzfile.h	8.1 (Berkeley) 6/2/93
35  */
36 
37 #ifndef _TZFILE_H_
38 #define	_TZFILE_H_
39 
40 /*
41  * Information about time zone files.
42  */
43 			/* Time zone object file directory */
44 #define TZDIR		"/usr/share/zoneinfo"
45 #define TZDEFAULT	"/etc/localtime"
46 #define TZDEFRULES	"posixrules"
47 
48 /*
49 ** Each file begins with. . .
50 */
51 
52 #define TZ_MAGIC	"TZif"
53 
54 struct tzhead {
55 	char	tzh_magic[4];		/* TZ_MAGIC */
56 	char	tzh_reserved[16];	/* reserved for future use */
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 */
63 };
64 
65 /*
66 ** . . .followed by. . .
67 **
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 wall clock time
86 **					if absent, transition times are
87 **					assumed to be local time
88 */
89 
90 /*
91 ** In the current implementation, "tzset()" refuses to deal with files that
92 ** exceed any of the limits below.
93 */
94 
95 /*
96 ** The TZ_MAX_TIMES value below is enough to handle a bit more than a
97 ** year's worth of solar time (corrected daily to the nearest second) or
98 ** 138 years of Pacific Presidential Election time
99 ** (where there are three time zone transitions every fourth year).
100 */
101 #define TZ_MAX_TIMES	370
102 
103 #define NOSOLAR			/* 4BSD doesn't currently handle solar time */
104 
105 #ifndef NOSOLAR
106 #define TZ_MAX_TYPES	256	/* Limited by what (unsigned char)'s can hold */
107 #else
108 #define TZ_MAX_TYPES	10	/* Maximum number of local time types */
109 #endif
110 
111 #define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */
112 
113 #define	TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */
114 
115 #define SECSPERMIN	60
116 #define MINSPERHOUR	60
117 #define HOURSPERDAY	24
118 #define DAYSPERWEEK	7
119 #define DAYSPERNYEAR	365
120 #define DAYSPERLYEAR	366
121 #define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
122 #define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
123 #define MONSPERYEAR	12
124 
125 #define TM_SUNDAY	0
126 #define TM_MONDAY	1
127 #define TM_TUESDAY	2
128 #define TM_WEDNESDAY	3
129 #define TM_THURSDAY	4
130 #define TM_FRIDAY	5
131 #define TM_SATURDAY	6
132 
133 #define TM_JANUARY	0
134 #define TM_FEBRUARY	1
135 #define TM_MARCH	2
136 #define TM_APRIL	3
137 #define TM_MAY		4
138 #define TM_JUNE		5
139 #define TM_JULY		6
140 #define TM_AUGUST	7
141 #define TM_SEPTEMBER	8
142 #define TM_OCTOBER	9
143 #define TM_NOVEMBER	10
144 #define TM_DECEMBER	11
145 
146 #define TM_YEAR_BASE	1900
147 
148 #define EPOCH_YEAR	1970
149 #define EPOCH_WDAY	TM_THURSDAY
150 
151 /*
152 ** Accurate only for the past couple of centuries;
153 ** that will probably do.
154 */
155 
156 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
157 
158 #endif /* !_TZFILE_H_ */
159