Always do locking when iterating over list of streams (bug 15142)
[glibc.git] / timezone / tzfile.h
blob0e51dce1d75936f27f43ad4b5c8d14970fb015d0
1 #ifndef TZFILE_H
3 #define TZFILE_H
5 /*
6 ** This file is in the public domain, so clarified as of
7 ** 1996-06-05 by Arthur David Olson.
8 */
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!
19 ** Information about time zone files.
22 #ifndef TZDIR
23 #define TZDIR "/usr/local/etc/zoneinfo" /* Time zone object file directory */
24 #endif /* !defined TZDIR */
26 #ifndef TZDEFAULT
27 #define TZDEFAULT "localtime"
28 #endif /* !defined TZDEFAULT */
30 #ifndef TZDEFRULES
31 #define TZDEFRULES "posixrules"
32 #endif /* !defined TZDEFRULES */
35 ** Each file begins with. . .
38 #define TZ_MAGIC "TZif"
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 */
53 ** . . .followed by. . .
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
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).
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.
95 ** In the current implementation, "tzset()" refuses to deal with files that
96 ** exceed any of the limits below.
99 #ifndef TZ_MAX_TIMES
100 #define TZ_MAX_TIMES 2000
101 #endif /* !defined TZ_MAX_TIMES */
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 */
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 */
113 #ifndef TZ_MAX_LEAPS
114 #define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */
115 #endif /* !defined TZ_MAX_LEAPS */
117 #endif /* !defined TZFILE_H */