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 | ** Information about time zone files. |
20 | */ |
21 | |
22 | #ifndef TZDIR |
23 | #define TZDIR "/usr/local/etc/zoneinfo" /* Time zone object file directory */ |
24 | #endif /* !defined TZDIR */ |
25 | |
26 | #ifndef TZDEFAULT |
27 | #define TZDEFAULT "localtime" |
28 | #endif /* !defined TZDEFAULT */ |
29 | |
30 | #ifndef TZDEFRULES |
31 | #define TZDEFRULES "posixrules" |
32 | #endif /* !defined TZDEFRULES */ |
33 | |
34 | /* |
35 | ** Each file begins with. . . |
36 | */ |
37 | |
38 | #define TZ_MAGIC "TZif" |
39 | |
40 | struct tzhead { |
41 | char tzh_magic[4]; /* TZ_MAGIC */ |
42 | char tzh_version[1]; /* '\0' or '2' or '3' as of 2013 */ |
43 | char tzh_reserved[15]; /* reserved; must be zero */ |
44 | char tzh_ttisgmtcnt[4]; /* coded number of trans. time flags */ |
45 | char tzh_ttisstdcnt[4]; /* coded number of trans. time flags */ |
46 | char tzh_leapcnt[4]; /* coded number of leap seconds */ |
47 | char tzh_timecnt[4]; /* coded number of transition times */ |
48 | char tzh_typecnt[4]; /* coded number of local time types */ |
49 | char tzh_charcnt[4]; /* coded number of abbr. chars */ |
50 | }; |
51 | |
52 | /* |
53 | ** . . .followed by. . . |
54 | ** |
55 | ** tzh_timecnt (char [4])s coded transition times a la time(2) |
56 | ** tzh_timecnt (unsigned char)s types of local time starting at above |
57 | ** tzh_typecnt repetitions of |
58 | ** one (char [4]) coded UT offset in seconds |
59 | ** one (unsigned char) used to set tm_isdst |
60 | ** one (unsigned char) that's an abbreviation list index |
61 | ** tzh_charcnt (char)s '\0'-terminated zone abbreviations |
62 | ** tzh_leapcnt repetitions of |
63 | ** one (char [4]) coded leap second transition times |
64 | ** one (char [4]) total correction after above |
65 | ** tzh_ttisstdcnt (char)s indexed by type; if 1, transition |
66 | ** time is standard time, if 0, |
67 | ** transition time is wall clock time |
68 | ** if absent, transition times are |
69 | ** assumed to be wall clock time |
70 | ** tzh_ttisgmtcnt (char)s indexed by type; if 1, transition |
71 | ** time is UT, if 0, |
72 | ** transition time is local time |
73 | ** if absent, transition times are |
74 | ** assumed to be local time |
75 | */ |
76 | |
77 | /* |
78 | ** If tzh_version is '2' or greater, the above is followed by a second instance |
79 | ** of tzhead and a second instance of the data in which each coded transition |
80 | ** time uses 8 rather than 4 chars, |
81 | ** then a POSIX-TZ-environment-variable-style string for use in handling |
82 | ** instants after the last transition time stored in the file |
83 | ** (with nothing between the newlines if there is no POSIX representation for |
84 | ** such instants). |
85 | ** |
86 | ** If tz_version is '3' or greater, the above is extended as follows. |
87 | ** First, the POSIX TZ string's hour offset may range from -167 |
88 | ** through 167 as compared to the POSIX-required 0 through 24. |
89 | ** Second, its DST start time may be January 1 at 00:00 and its stop |
90 | ** time December 31 at 24:00 plus the difference between DST and |
91 | ** standard time, indicating DST all year. |
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 | #ifndef TZ_MAX_TIMES |
100 | #define TZ_MAX_TIMES 2000 |
101 | #endif /* !defined TZ_MAX_TIMES */ |
102 | |
103 | #ifndef TZ_MAX_TYPES |
104 | /* This must be at least 17 for Europe/Samara and Europe/Vilnius. */ |
105 | #define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */ |
106 | #endif /* !defined TZ_MAX_TYPES */ |
107 | |
108 | #ifndef TZ_MAX_CHARS |
109 | #define TZ_MAX_CHARS 50 /* Maximum number of abbreviation characters */ |
110 | /* (limited by what unsigned chars can hold) */ |
111 | #endif /* !defined TZ_MAX_CHARS */ |
112 | |
113 | #ifndef TZ_MAX_LEAPS |
114 | #define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */ |
115 | #endif /* !defined TZ_MAX_LEAPS */ |
116 | |
117 | #define SECSPERMIN 60 |
118 | #define MINSPERHOUR 60 |
119 | #define HOURSPERDAY 24 |
120 | #define DAYSPERWEEK 7 |
121 | #define DAYSPERNYEAR 365 |
122 | #define DAYSPERLYEAR 366 |
123 | #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR) |
124 | #define SECSPERDAY ((int_fast32_t) SECSPERHOUR * HOURSPERDAY) |
125 | #define MONSPERYEAR 12 |
126 | |
127 | #define TM_SUNDAY 0 |
128 | #define TM_MONDAY 1 |
129 | #define TM_TUESDAY 2 |
130 | #define TM_WEDNESDAY 3 |
131 | #define TM_THURSDAY 4 |
132 | #define TM_FRIDAY 5 |
133 | #define TM_SATURDAY 6 |
134 | |
135 | #define TM_JANUARY 0 |
136 | #define TM_FEBRUARY 1 |
137 | #define TM_MARCH 2 |
138 | #define TM_APRIL 3 |
139 | #define TM_MAY 4 |
140 | #define TM_JUNE 5 |
141 | #define TM_JULY 6 |
142 | #define TM_AUGUST 7 |
143 | #define TM_SEPTEMBER 8 |
144 | #define TM_OCTOBER 9 |
145 | #define TM_NOVEMBER 10 |
146 | #define TM_DECEMBER 11 |
147 | |
148 | #define TM_YEAR_BASE 1900 |
149 | |
150 | #define EPOCH_YEAR 1970 |
151 | #define EPOCH_WDAY TM_THURSDAY |
152 | |
153 | #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0)) |
154 | |
155 | /* |
156 | ** Since everything in isleap is modulo 400 (or a factor of 400), we know that |
157 | ** isleap(y) == isleap(y % 400) |
158 | ** and so |
159 | ** isleap(a + b) == isleap((a + b) % 400) |
160 | ** or |
161 | ** isleap(a + b) == isleap(a % 400 + b % 400) |
162 | ** This is true even if % means modulo rather than Fortran remainder |
163 | ** (which is allowed by C89 but not C99). |
164 | ** We use this to avoid addition overflow problems. |
165 | */ |
166 | |
167 | #define isleap_sum(a, b) isleap((a) % 400 + (b) % 400) |
168 | |
169 | #endif /* !defined TZFILE_H */ |
170 | |