glibc/timezone/tzfile.h
Paul Eggert 1f94147a79 timezone: sync to TZDB 2024a
Sync tzselect, zdump, zic to TZDB 2024a.
This patch incorporates the following TZDB source code changes,
listed roughly in descending order of importance.

  zic now supports links to links, needed for future tzdata
  zic now defaults to '-b slim'
  zic now updates output files atomically
  zic has new options -R, -l -, -p -
  zic -r now uses -00 for unspecified timestamps
  zdump now uses [lo,hi) for both -c and -t
  Fix several integer overflow bugs
  zic now checks input bytes more carefully
  Simplify and fix new TZDIR setup
  Default time_t to 64 bits on glibc 2.34+ 32-bit
  zic now generates TZ strings that conform to POSIX when all-year DST
  zic -v now shows extreme-int tm_year transitions
  Fix zic bug in last time type of Asia/Gaza etc.
  Fix zic bug with Palestine after 2075
  Fix bug uncovered by recent change to Iran history
  Fix 'zic -b fat' bug with Port Moresby 32-bit data
  Fix zic bug with -r @X where X is deduced from TZ
  Fix bug with zic -r cutoff before 1st transition
  Fix leap second expiry and truncation
  Fix zic bug on Linux 2.6.16 and 2.6.17
  Fix bug with 'zic -d /a/b/c' if /a is unwriteable
  Don't mistruncate TZif files at leap seconds
  Fix zdump undefined behavior if !USE_LTZ
  zdump -v reports localtime+gmtime failures better
  Fix zdump diagnostic for missing timezone
  Don't assume nonempty argv
  Port better to C23
  Do not assume negative >> behavior
  I18nize zdump a bit better
  Port zdump to right_only installations
  New tzselect menu option 'now'
  tzselect can now use current time to help choose
  Improve tzselect behavior for Turkey etc.
  tzselect: do not create temporary files
  tzselect: work around mawk bug with {2,}
  tzselect: Port to POSIX awk, which prohibits -v newlines
  Do not use empty RE in tzselect
  Don't set TZ in tzselect
  Avoid sed, expr in tzselect
  tzselect: Fix problems with spaces in TZDIR
  Improve tzselect diagnostics
  Remove zic workaround for Qt bug 53071
  Remove zic support for "min" in Rule lines
  Remove zic support for zic -y, Rule TYPEs, pacificnew
  Remove tzselect workaround for Bash 1.14.7 bug

* SHARED-FILES: Update to match current sync.
* config.h.in (HAVE_STRERROR): Remove; no longer needed.
* timezone/Makefile ($(objpfx)zic.o): Depend on tzdir.h.
($(objpfx)tzdir.h): New rule to build a placeholder.
* timezone/private.h, timezone/tzfile.h, timezone/version:
* timezone/zdump.c, timezone/zic.c: Copy verbatim from TZDB 2024a.
2024-04-07 13:35:48 -07:00

120 lines
4.0 KiB
C

/* 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 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'-'4' as of 2021 */
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 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.1-2017
** representation for such instants).
**
** If tz_version is '3' or greater, the above is extended as follows.
** First, the TZ 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
/* This must be at least 242 for Europe/London with 'zic -b fat'. */
# define TZ_MAX_TIMES 2000
#endif /* !defined TZ_MAX_TIMES */
#ifndef TZ_MAX_TYPES
/* This must be at least 18 for Europe/Vilnius with 'zic -b fat'. */
# define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */
#endif /* !defined TZ_MAX_TYPES */
#ifndef TZ_MAX_CHARS
/* This must be at least 40 for America/Anchorage. */
# 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
/* This must be at least 27 for leap seconds from 1972 through mid-2023.
There's a plan to discontinue leap seconds by 2035. */
# define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */
#endif /* !defined TZ_MAX_LEAPS */
#endif /* !defined TZFILE_H */