| /* Layout and location of TZif files. */ |
| |
| #ifndef TZFILE_H |
| |
| #define TZFILE_H |
| |
| /* |
| ** This file is in the public domain, so clarified as of |
| ** 1996-06-05 by Arthur David Olson. |
| */ |
| |
| /* |
| ** This header is for use ONLY with the time conversion code. |
| ** There is no guarantee that it will remain unchanged, |
| ** or that it will remain at all. |
| ** Do NOT copy it to any system include directory. |
| ** Thank you! |
| */ |
| |
| /* |
| ** Information about time zone files. |
| */ |
| |
| #ifndef TZDIR |
| #define TZDIR "/usr/share/zoneinfo" /* Time zone object file directory */ |
| #endif /* !defined TZDIR */ |
| |
| #ifndef TZDEFAULT |
| #define TZDEFAULT "/etc/localtime" |
| #endif /* !defined TZDEFAULT */ |
| |
| #ifndef TZDEFRULES |
| #define TZDEFRULES "posixrules" |
| #endif /* !defined TZDEFRULES */ |
| |
| /* See Internet RFC 8536 for more details about the following format. */ |
| |
| /* |
| ** Each file begins with. . . |
| */ |
| |
| #define TZ_MAGIC "TZif" |
| |
| struct tzhead { |
| char tzh_magic[4]; /* TZ_MAGIC */ |
| char tzh_version[1]; /* '\0' or '2' or '3' as of 2013 */ |
| char tzh_reserved[15]; /* reserved; must be zero */ |
| char tzh_ttisutcnt[4]; /* coded number of trans. time flags */ |
| char tzh_ttisstdcnt[4]; /* coded number of trans. time flags */ |
| char tzh_leapcnt[4]; /* coded number of leap seconds */ |
| char tzh_timecnt[4]; /* coded number of transition times */ |
| char tzh_typecnt[4]; /* coded number of local time types */ |
| char tzh_charcnt[4]; /* coded number of abbr. chars */ |
| }; |
| |
| /* |
| ** . . .followed by. . . |
| ** |
| ** tzh_timecnt (char [4])s coded transition times a la time(2) |
| ** tzh_timecnt (unsigned char)s types of local time starting at above |
| ** tzh_typecnt repetitions of |
| ** one (char [4]) coded UT offset in seconds |
| ** one (unsigned char) used to set tm_isdst |
| ** one (unsigned char) that's an abbreviation list index |
| ** tzh_charcnt (char)s '\0'-terminated zone abbreviations |
| ** tzh_leapcnt repetitions of |
| ** one (char [4]) coded leap second transition times |
| ** one (char [4]) total correction after above |
| ** tzh_ttisstdcnt (char)s indexed by type; if 1, transition |
| ** time is standard time, if 0, |
| ** transition time is local (wall clock) |
| ** time; if absent, transition times are |
| ** assumed to be local time |
| ** tzh_ttisutcnt (char)s indexed by type; if 1, transition |
| ** time is UT, if 0, transition time is |
| ** local time; if absent, transition |
| ** times are assumed to be local time. |
| ** When this is 1, the corresponding |
| ** std/wall indicator must also be 1. |
| */ |
| |
| /* |
| ** If tzh_version is '2' or greater, the above is followed by a second instance |
| ** of tzhead and a second instance of the data in which each coded transition |
| ** time uses 8 rather than 4 chars, |
| ** then a POSIX-TZ-environment-variable-style std::string for use in handling |
| ** instants after the last transition time stored in the file |
| ** (with nothing between the newlines if there is no POSIX representation for |
| ** such instants). |
| ** |
| ** If tz_version is '3' or greater, the above is extended as follows. |
| ** First, the POSIX TZ std::string's hour offset may range from -167 |
| ** through 167 as compared to the POSIX-required 0 through 24. |
| ** Second, its DST start time may be January 1 at 00:00 and its stop |
| ** time December 31 at 24:00 plus the difference between DST and |
| ** standard time, indicating DST all year. |
| */ |
| |
| /* |
| ** In the current implementation, "tzset()" refuses to deal with files that |
| ** exceed any of the limits below. |
| */ |
| |
| #ifndef TZ_MAX_TIMES |
| #define TZ_MAX_TIMES 2000 |
| #endif /* !defined TZ_MAX_TIMES */ |
| |
| #ifndef TZ_MAX_TYPES |
| /* This must be at least 17 for Europe/Samara and Europe/Vilnius. */ |
| #define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */ |
| #endif /* !defined TZ_MAX_TYPES */ |
| |
| #ifndef TZ_MAX_CHARS |
| #define TZ_MAX_CHARS 50 /* Maximum number of abbreviation characters */ |
| /* (limited by what unsigned chars can hold) */ |
| #endif /* !defined TZ_MAX_CHARS */ |
| |
| #ifndef TZ_MAX_LEAPS |
| #define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */ |
| #endif /* !defined TZ_MAX_LEAPS */ |
| |
| #endif /* !defined TZFILE_H */ |