xref: /src/include/tzfile.h

/*	$NetBSD: tzfile.h,v 1.6 1998/07/30 14:11:22 kleink Exp $	*/

/*
 * Copyright (c) 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Arthur David Olson of the National Cancer Institute.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)tzfile.h	8.1 (Berkeley) 6/2/93
 */

#ifndef _TZFILE_H_
#define	_TZFILE_H_

/*
 * Information about time zone files.
 */
			/* Time zone object file directory */
#define TZDIR		"/usr/share/zoneinfo"
#define TZDEFAULT	"/etc/localtime"
#define TZDEFRULES	"posixrules"

/*
** Each file begins with. . .
*/

#define TZ_MAGIC	"TZif"

struct tzhead {
	char	tzh_magic[4];		/* TZ_MAGIC */
	char	tzh_reserved[16];	/* reserved for future use */
	char	tzh_ttisgmtcnt[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 UTC 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 TRUE, transition
**					time is standard time, if FALSE,
**					transition time is wall clock time
**					if absent, transition times are
**					assumed to be wall clock time
**	tzh_ttisgmtcnt (char)s		indexed by type; if TRUE, transition
**					time is UTC, if FALSE,
**					transition time is wall clock time
**					if absent, transition times are
**					assumed to be local time
*/

/*
** In the current implementation, "tzset()" refuses to deal with files that
** exceed any of the limits below.
*/

/*
** The TZ_MAX_TIMES value below is enough to handle a bit more than a
** year's worth of solar time (corrected daily to the nearest second) or
** 138 years of Pacific Presidential Election time
** (where there are three time zone transitions every fourth year).
*/
#define TZ_MAX_TIMES	370

#define NOSOLAR			/* 4BSD doesn't currently handle solar time */

#ifndef NOSOLAR
#define TZ_MAX_TYPES	256	/* Limited by what (unsigned char)'s can hold */
#else
#define TZ_MAX_TYPES	10	/* Maximum number of local time types */
#endif

#define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */

#define	TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */

#define SECSPERMIN	60
#define MINSPERHOUR	60
#define HOURSPERDAY	24
#define DAYSPERWEEK	7
#define DAYSPERNYEAR	365
#define DAYSPERLYEAR	366
#define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
#define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
#define MONSPERYEAR	12

#define TM_SUNDAY	0
#define TM_MONDAY	1
#define TM_TUESDAY	2
#define TM_WEDNESDAY	3
#define TM_THURSDAY	4
#define TM_FRIDAY	5
#define TM_SATURDAY	6

#define TM_JANUARY	0
#define TM_FEBRUARY	1
#define TM_MARCH	2
#define TM_APRIL	3
#define TM_MAY		4
#define TM_JUNE		5
#define TM_JULY		6
#define TM_AUGUST	7
#define TM_SEPTEMBER	8
#define TM_OCTOBER	9
#define TM_NOVEMBER	10
#define TM_DECEMBER	11

#define TM_YEAR_BASE	1900

#define EPOCH_YEAR	1970
#define EPOCH_WDAY	TM_THURSDAY

/*
** Accurate only for the past couple of centuries;
** that will probably do.
*/

#define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)

#endif /* !_TZFILE_H_ */