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/share/zoneinfo" /* Time zone object file directory */ 24 #endif /* !defined TZDIR */ 25 26 #ifndef TZDEFAULT 27 #define TZDEFAULT "/etc/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' as of 2005 */ 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 UTC 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 UTC, 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 87 /* 88 ** In the current implementation, "tzset()" refuses to deal with files that 89 ** exceed any of the limits below. 90 */ 91 92 #ifndef TZ_MAX_TIMES 93 #define TZ_MAX_TIMES 1200 94 #endif /* !defined TZ_MAX_TIMES */ 95 96 #ifndef TZ_MAX_TYPES 97 #ifndef NOSOLAR 98 #define TZ_MAX_TYPES 256 /* Limited by what (unsigned char)'s can hold */ 99 #endif /* !defined NOSOLAR */ 100 #ifdef NOSOLAR 101 /* 102 ** Must be at least 14 for Europe/Riga as of Jan 12 1995, 103 ** as noted by Earl Chew. 104 */ 105 #define TZ_MAX_TYPES 20 /* Maximum number of local time types */ 106 #endif /* !defined NOSOLAR */ 107 #endif /* !defined TZ_MAX_TYPES */ 108 109 #ifndef TZ_MAX_CHARS 110 #define TZ_MAX_CHARS 50 /* Maximum number of abbreviation characters */ 111 /* (limited by what unsigned chars can hold) */ 112 #endif /* !defined TZ_MAX_CHARS */ 113 114 #ifndef TZ_MAX_LEAPS 115 #define TZ_MAX_LEAPS 50 /* Maximum number of leap second corrections */ 116 #endif /* !defined TZ_MAX_LEAPS */ 117 118 #define SECSPERMIN 60 119 #define MINSPERHOUR 60 120 #define HOURSPERDAY 24 121 #define DAYSPERWEEK 7 122 #define DAYSPERNYEAR 365 123 #define DAYSPERLYEAR 366 124 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR) 125 #define SECSPERDAY ((long) SECSPERHOUR * HOURSPERDAY) 126 #define MONSPERYEAR 12 127 128 #define TM_SUNDAY 0 129 #define TM_MONDAY 1 130 #define TM_TUESDAY 2 131 #define TM_WEDNESDAY 3 132 #define TM_THURSDAY 4 133 #define TM_FRIDAY 5 134 #define TM_SATURDAY 6 135 136 #define TM_JANUARY 0 137 #define TM_FEBRUARY 1 138 #define TM_MARCH 2 139 #define TM_APRIL 3 140 #define TM_MAY 4 141 #define TM_JUNE 5 142 #define TM_JULY 6 143 #define TM_AUGUST 7 144 #define TM_SEPTEMBER 8 145 #define TM_OCTOBER 9 146 #define TM_NOVEMBER 10 147 #define TM_DECEMBER 11 148 149 #define TM_YEAR_BASE 1900 150 151 #define EPOCH_YEAR 1970 152 #define EPOCH_WDAY TM_THURSDAY 153 154 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0)) 155 156 /* 157 ** Since everything in isleap is modulo 400 (or a factor of 400), we know that 158 ** isleap(y) == isleap(y % 400) 159 ** and so 160 ** isleap(a + b) == isleap((a + b) % 400) 161 ** or 162 ** isleap(a + b) == isleap(a % 400 + b % 400) 163 ** This is true even if % means modulo rather than Fortran remainder 164 ** (which is allowed by C89 but not C99). 165 ** We use this to avoid addition overflow problems. 166 */ 167 168 #define isleap_sum(a, b) isleap((a) % 400 + (b) % 400) 169 170 #endif /* !defined TZFILE_H */ 171