1 /**	$MirOS: src/lib/libc/time/tzfile.h,v 1.3 2005/09/22 20:33:02 tg Exp $ */
2 /*	$OpenBSD: tzfile.h,v 1.6 2005/07/05 13:40:51 millert Exp $	*/
3 
4 #ifndef TZFILE_H
5 #define TZFILE_H
6 
7 /*
8 ** This file is in the public domain, so clarified as of
9 ** 1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov).
10 */
11 
12 /*
13 ** This header is for use ONLY with the time conversion code.
14 ** There is no guarantee that it will remain unchanged,
15 ** or that it will remain at all.
16 ** Do NOT copy it to any system include directory.
17 ** Thank you!
18 */
19 
20 /*
21 ** ID
22 */
23 
24 #if 0
25 #ifndef lint
26 #ifndef NOID
27 static char	tzfilehid[] = "@(#)tzfile.h	7.17";
28 #endif /* !defined NOID */
29 #endif /* !defined lint */
30 #endif
31 
32 /*
33 ** Information about time zone files.
34 */
35 
36 #ifndef TZDIR
37 #define TZDIR	"/usr/share/zoneinfo" /* Time zone object file directory */
38 #endif /* !defined TZDIR */
39 
40 #ifndef TZDEFAULT
41 #define TZDEFAULT	"/etc/localtime"
42 #endif /* !defined TZDEFAULT */
43 
44 #ifndef TZDEFRULES
45 #define TZDEFRULES	"posixrules"
46 #endif /* !defined TZDEFRULES */
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 local 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 #ifndef TZ_MAX_TIMES
96 /*
97 ** The TZ_MAX_TIMES value below is enough to handle a bit more than a
98 ** year's worth of solar time (corrected daily to the nearest second) or
99 ** 138 years of Pacific Presidential Election time
100 ** (where there are three time zone transitions every fourth year).
101 */
102 #define TZ_MAX_TIMES	370
103 #endif /* !defined TZ_MAX_TIMES */
104 
105 #ifndef TZ_MAX_TYPES
106 #ifndef NOSOLAR
107 #define TZ_MAX_TYPES	256 /* Limited by what (unsigned char)'s can hold */
108 #endif /* !defined NOSOLAR */
109 #ifdef NOSOLAR
110 /*
111 ** Must be at least 14 for Europe/Riga as of Jan 12 1995,
112 ** as noted by Earl Chew <earl@hpato.aus.hp.com>.
113 */
114 #define TZ_MAX_TYPES	20	/* Maximum number of local time types */
115 #endif /* !defined NOSOLAR */
116 #endif /* !defined TZ_MAX_TYPES */
117 
118 #ifndef TZ_MAX_CHARS
119 #define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */
120 				/* (limited by what unsigned chars can hold) */
121 #endif /* !defined TZ_MAX_CHARS */
122 
123 #ifndef TZ_MAX_LEAPS
124 #define TZ_MAX_LEAPS	128	/* Maximum number of leap second corrections */
125 #endif /* !defined TZ_MAX_LEAPS */
126 
127 #define SECSPERMIN	60
128 #define MINSPERHOUR	60
129 #define HOURSPERDAY	24
130 #define DAYSPERWEEK	7
131 #define DAYSPERNYEAR	365
132 #define DAYSPERLYEAR	366
133 #define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
134 #define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
135 #define MONSPERYEAR	12
136 
137 #define TM_SUNDAY	0
138 #define TM_MONDAY	1
139 #define TM_TUESDAY	2
140 #define TM_WEDNESDAY	3
141 #define TM_THURSDAY	4
142 #define TM_FRIDAY	5
143 #define TM_SATURDAY	6
144 
145 #define TM_JANUARY	0
146 #define TM_FEBRUARY	1
147 #define TM_MARCH	2
148 #define TM_APRIL	3
149 #define TM_MAY		4
150 #define TM_JUNE		5
151 #define TM_JULY		6
152 #define TM_AUGUST	7
153 #define TM_SEPTEMBER	8
154 #define TM_OCTOBER	9
155 #define TM_NOVEMBER	10
156 #define TM_DECEMBER	11
157 
158 #define TM_YEAR_BASE	1900
159 
160 #define EPOCH_YEAR	1970
161 #define EPOCH_WDAY	TM_THURSDAY
162 
163 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
164 
165 /*
166 ** Since everything in isleap is modulo 400 (or a factor of 400), we know that
167 **	isleap(y) == isleap(y % 400)
168 ** and so
169 **	isleap(a + b) == isleap((a + b) % 400)
170 ** or
171 **	isleap(a + b) == isleap(a % 400 + b % 400)
172 ** This is true even if % means modulo rather than Fortran remainder
173 ** (which is allowed by C89 but not C99).
174 ** We use this to avoid addition overflow problems.
175 */
176 
177 #define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
178 
179 #endif /* !defined TZFILE_H */
180