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 40struct 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 */ 170