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Commit	Line	Data
	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 TRUE, transition
	66	** time is standard time, if FALSE,
	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 TRUE, transition
	71	** time is UT, if FALSE,
	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 */