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1 #ifndef TZFILE_H
2 
3 #define TZFILE_H
4 
5 /*
6 ** This file is in the public domain, so clarified as of
7 ** 1996-06-05 by Arthur David Olson.
8 */
9 
10 /*
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!
16 */
17 
18 /*
19 ** ID
20 */
21 
22 #ifndef lint
23 #ifndef NOID
24 static char	tzfilehid[] = "@(#)tzfile.h	8.1";
25 #endif /* !defined NOID */
26 #endif /* !defined lint */
27 
28 /*
29 ** Information about time zone files.
30 */
31 
32 #ifndef TZDIR
33 #define TZDIR	"/usr/local/etc/zoneinfo" /* Time zone object file directory */
34 #endif /* !defined TZDIR */
35 
36 #ifndef TZDEFAULT
37 #define TZDEFAULT	"localtime"
38 #endif /* !defined TZDEFAULT */
39 
40 #ifndef TZDEFRULES
41 #define TZDEFRULES	"posixrules"
42 #endif /* !defined TZDEFRULES */
43 
44 /*
45 ** Each file begins with. . .
46 */
47 
48 #define	TZ_MAGIC	"TZif"
49 
50 struct tzhead {
51 	char	tzh_magic[4];		/* TZ_MAGIC */
52 	char	tzh_version[1];		/* '\0' or '2' as of 2005 */
53 	char	tzh_reserved[15];	/* reserved--must be zero */
54 	char	tzh_ttisgmtcnt[4];	/* coded number of trans. time flags */
55 	char	tzh_ttisstdcnt[4];	/* coded number of trans. time flags */
56 	char	tzh_leapcnt[4];		/* coded number of leap seconds */
57 	char	tzh_timecnt[4];		/* coded number of transition times */
58 	char	tzh_typecnt[4];		/* coded number of local time types */
59 	char	tzh_charcnt[4];		/* coded number of abbr. chars */
60 };
61 
62 /*
63 ** . . .followed by. . .
64 **
65 **	tzh_timecnt (char [4])s		coded transition times a la time(2)
66 **	tzh_timecnt (unsigned char)s	types of local time starting at above
67 **	tzh_typecnt repetitions of
68 **		one (char [4])		coded UTC offset in seconds
69 **		one (unsigned char)	used to set tm_isdst
70 **		one (unsigned char)	that's an abbreviation list index
71 **	tzh_charcnt (char)s		'\0'-terminated zone abbreviations
72 **	tzh_leapcnt repetitions of
73 **		one (char [4])		coded leap second transition times
74 **		one (char [4])		total correction after above
75 **	tzh_ttisstdcnt (char)s		indexed by type; if TRUE, transition
76 **					time is standard time, if FALSE,
77 **					transition time is wall clock time
78 **					if absent, transition times are
79 **					assumed to be wall clock time
80 **	tzh_ttisgmtcnt (char)s		indexed by type; if TRUE, transition
81 **					time is UTC, if FALSE,
82 **					transition time is local time
83 **					if absent, transition times are
84 **					assumed to be local time
85 */
86 
87 /*
88 ** If tzh_version is '2' or greater, the above is followed by a second instance
89 ** of tzhead and a second instance of the data in which each coded transition
90 ** time uses 8 rather than 4 chars,
91 ** then a POSIX-TZ-environment-variable-style string for use in handling
92 ** instants after the last transition time stored in the file
93 ** (with nothing between the newlines if there is no POSIX representation for
94 ** such instants).
95 */
96 
97 /*
98 ** In the current implementation, "tzset()" refuses to deal with files that
99 ** exceed any of the limits below.
100 */
101 
102 #ifndef TZ_MAX_TIMES
103 #define TZ_MAX_TIMES	1200
104 #endif /* !defined TZ_MAX_TIMES */
105 
106 #ifndef TZ_MAX_TYPES
107 #ifndef NOSOLAR
108 #define TZ_MAX_TYPES	256 /* Limited by what (unsigned char)'s can hold */
109 #endif /* !defined NOSOLAR */
110 #ifdef NOSOLAR
111 /*
112 ** Must be at least 14 for Europe/Riga as of Jan 12 1995,
113 ** as noted by Earl Chew.
114 */
115 #define TZ_MAX_TYPES	20	/* Maximum number of local time types */
116 #endif /* !defined NOSOLAR */
117 #endif /* !defined TZ_MAX_TYPES */
118 
119 #ifndef TZ_MAX_CHARS
120 #define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */
121 				/* (limited by what unsigned chars can hold) */
122 #endif /* !defined TZ_MAX_CHARS */
123 
124 #ifndef TZ_MAX_LEAPS
125 #define TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */
126 #endif /* !defined TZ_MAX_LEAPS */
127 
128 #define SECSPERMIN	60
129 #define MINSPERHOUR	60
130 #define HOURSPERDAY	24
131 #define DAYSPERWEEK	7
132 #define DAYSPERNYEAR	365
133 #define DAYSPERLYEAR	366
134 #define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
135 #define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
136 #define MONSPERYEAR	12
137 
138 #define TM_SUNDAY	0
139 #define TM_MONDAY	1
140 #define TM_TUESDAY	2
141 #define TM_WEDNESDAY	3
142 #define TM_THURSDAY	4
143 #define TM_FRIDAY	5
144 #define TM_SATURDAY	6
145 
146 #define TM_JANUARY	0
147 #define TM_FEBRUARY	1
148 #define TM_MARCH	2
149 #define TM_APRIL	3
150 #define TM_MAY		4
151 #define TM_JUNE		5
152 #define TM_JULY		6
153 #define TM_AUGUST	7
154 #define TM_SEPTEMBER	8
155 #define TM_OCTOBER	9
156 #define TM_NOVEMBER	10
157 #define TM_DECEMBER	11
158 
159 #define TM_YEAR_BASE	1900
160 
161 #define EPOCH_YEAR	1970
162 #define EPOCH_WDAY	TM_THURSDAY
163 
164 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
165 
166 /*
167 ** Since everything in isleap is modulo 400 (or a factor of 400), we know that
168 **	isleap(y) == isleap(y % 400)
169 ** and so
170 **	isleap(a + b) == isleap((a + b) % 400)
171 ** or
172 **	isleap(a + b) == isleap(a % 400 + b % 400)
173 ** This is true even if % means modulo rather than Fortran remainder
174 ** (which is allowed by C89 but not C99).
175 ** We use this to avoid addition overflow problems.
176 */
177 
178 #define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
179 
180 #endif /* !defined TZFILE_H */
181