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      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 ** ID
     20 */
     21 
     22 #ifndef lint
     23 #ifndef NOID
     24 static char	tzfilehid[] = "@(#)tzfile.h	8.1";
     25 #endif /* !defined NOID */
     26 #endif /* !defined lint */
     27 
     28 /*
     29 ** Information about time zone files.
     30 */
     31 
     32 #ifndef TZDIR
     33 #define TZDIR "/usr/share/zoneinfo" /* "/android/usr/share/zoneinfo" */ /* Time zone object file directory */
     34 #endif /* !defined TZDIR */
     35 
     36 #ifndef TZDEFAULT
     37 #define TZDEFAULT	"localtime"
     38 #endif /* !defined TZDEFAULT */
     39 
     40 #ifndef TZDEFRULES
     41 #define TZDEFRULES	"posixrules"
     42 #endif /* !defined TZDEFRULES */
     43 
     44 /*
     45 ** Each file begins with. . .
     46 */
     47 
     48 #define	TZ_MAGIC	"TZif"
     49 
     50 struct tzhead {
     51 	char	tzh_magic[4];		/* TZ_MAGIC */
     52 	char	tzh_version[1];		/* '\0' or '2' as of 2005 */
     53 	char	tzh_reserved[15];	/* reserved--must be zero */
     54 	char	tzh_ttisgmtcnt[4];	/* coded number of trans. time flags */
     55 	char	tzh_ttisstdcnt[4];	/* coded number of trans. time flags */
     56 	char	tzh_leapcnt[4];		/* coded number of leap seconds */
     57 	char	tzh_timecnt[4];		/* coded number of transition times */
     58 	char	tzh_typecnt[4];		/* coded number of local time types */
     59 	char	tzh_charcnt[4];		/* coded number of abbr. chars */
     60 };
     61 
     62 /*
     63 ** . . .followed by. . .
     64 **
     65 **	tzh_timecnt (char [4])s		coded transition times a la time(2)
     66 **	tzh_timecnt (unsigned char)s	types of local time starting at above
     67 **	tzh_typecnt repetitions of
     68 **		one (char [4])		coded UTC offset in seconds
     69 **		one (unsigned char)	used to set tm_isdst
     70 **		one (unsigned char)	that's an abbreviation list index
     71 **	tzh_charcnt (char)s		'\0'-terminated zone abbreviations
     72 **	tzh_leapcnt repetitions of
     73 **		one (char [4])		coded leap second transition times
     74 **		one (char [4])		total correction after above
     75 **	tzh_ttisstdcnt (char)s		indexed by type; if TRUE, transition
     76 **					time is standard time, if FALSE,
     77 **					transition time is wall clock time
     78 **					if absent, transition times are
     79 **					assumed to be wall clock time
     80 **	tzh_ttisgmtcnt (char)s		indexed by type; if TRUE, transition
     81 **					time is UTC, if FALSE,
     82 **					transition time is local time
     83 **					if absent, transition times are
     84 **					assumed to be local time
     85 */
     86 
     87 /*
     88 ** If tzh_version is '2' or greater, the above is followed by a second instance
     89 ** of tzhead and a second instance of the data in which each coded transition
     90 ** time uses 8 rather than 4 chars,
     91 ** then a POSIX-TZ-environment-variable-style string for use in handling
     92 ** instants after the last transition time stored in the file
     93 ** (with nothing between the newlines if there is no POSIX representation for
     94 ** such instants).
     95 */
     96 
     97 /*
     98 ** In the current implementation, "tzset()" refuses to deal with files that
     99 ** exceed any of the limits below.
    100 */
    101 
    102 #ifndef TZ_MAX_TIMES
    103 #define TZ_MAX_TIMES	1200
    104 #endif /* !defined TZ_MAX_TIMES */
    105 
    106 #ifndef TZ_MAX_TYPES
    107 #ifndef NOSOLAR
    108 #define TZ_MAX_TYPES	256 /* Limited by what (unsigned char)'s can hold */
    109 #endif /* !defined NOSOLAR */
    110 #ifdef NOSOLAR
    111 /*
    112 ** Must be at least 14 for Europe/Riga as of Jan 12 1995,
    113 ** as noted by Earl Chew.
    114 */
    115 #define TZ_MAX_TYPES	20	/* Maximum number of local time types */
    116 #endif /* !defined NOSOLAR */
    117 #endif /* !defined TZ_MAX_TYPES */
    118 
    119 #ifndef TZ_MAX_CHARS
    120 #define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */
    121 				/* (limited by what unsigned chars can hold) */
    122 #endif /* !defined TZ_MAX_CHARS */
    123 
    124 #ifndef TZ_MAX_LEAPS
    125 #define TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */
    126 #endif /* !defined TZ_MAX_LEAPS */
    127 
    128 #define SECSPERMIN	60
    129 #define MINSPERHOUR	60
    130 #define HOURSPERDAY	24
    131 #define DAYSPERWEEK	7
    132 #define DAYSPERNYEAR	365
    133 #define DAYSPERLYEAR	366
    134 #define SECSPERHOUR	(SECSPERMIN * MINSPERHOUR)
    135 #define SECSPERDAY	((long) SECSPERHOUR * HOURSPERDAY)
    136 #define MONSPERYEAR	12
    137 
    138 #define TM_SUNDAY	0
    139 #define TM_MONDAY	1
    140 #define TM_TUESDAY	2
    141 #define TM_WEDNESDAY	3
    142 #define TM_THURSDAY	4
    143 #define TM_FRIDAY	5
    144 #define TM_SATURDAY	6
    145 
    146 #define TM_JANUARY	0
    147 #define TM_FEBRUARY	1
    148 #define TM_MARCH	2
    149 #define TM_APRIL	3
    150 #define TM_MAY		4
    151 #define TM_JUNE		5
    152 #define TM_JULY		6
    153 #define TM_AUGUST	7
    154 #define TM_SEPTEMBER	8
    155 #define TM_OCTOBER	9
    156 #define TM_NOVEMBER	10
    157 #define TM_DECEMBER	11
    158 
    159 #define TM_YEAR_BASE	1900
    160 
    161 #define EPOCH_YEAR	1970
    162 #define EPOCH_WDAY	TM_THURSDAY
    163 
    164 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
    165 
    166 /*
    167 ** Since everything in isleap is modulo 400 (or a factor of 400), we know that
    168 **	isleap(y) == isleap(y % 400)
    169 ** and so
    170 **	isleap(a + b) == isleap((a + b) % 400)
    171 ** or
    172 **	isleap(a + b) == isleap(a % 400 + b % 400)
    173 ** This is true even if % means modulo rather than Fortran remainder
    174 ** (which is allowed by C89 but not C99).
    175 ** We use this to avoid addition overflow problems.
    176 */
    177 
    178 #define isleap_sum(a, b)	isleap((a) % 400 + (b) % 400)
    179 
    180 #endif /* !defined TZFILE_H */
    181