1 #ifndef TZFILE_INCLUDED
2 #define TZFILE_INCLUDED
3 
4 /* Copyright (c) 2004, 2006, 2007 MySQL AB, 2009 Sun Microsystems, Inc.
5    Use is subject to license terms.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; version 2 of the License.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
19 
20 /*
21    This file is based on public domain code from ftp://elsie.ncih.nist.gov/
22    Initial source code is in the public domain, so clarified as of
23    1996-06-05 by Arthur David Olson (arthur_david_olson@nih.gov).
24 */
25 
26 /*
27   Information about time zone files.
28 */
29 
30 #ifndef TZDIR
31 #define TZDIR	"/usr/share/zoneinfo" /* Time zone object file directory */
32 #endif /* !defined TZDIR */
33 
34 /*
35   Each file begins with. . .
36 */
37 
38 #define	TZ_MAGIC	"TZif"
39 
40 struct tzhead {
41  	uchar	tzh_magic[4];		/* TZ_MAGIC */
42 	uchar	tzh_reserved[16];	/* reserved for future use */
43 	uchar	tzh_ttisgmtcnt[4];	/* coded number of trans. time flags */
44 	uchar	tzh_ttisstdcnt[4];	/* coded number of trans. time flags */
45 	uchar	tzh_leapcnt[4];		/* coded number of leap seconds */
46 	uchar	tzh_timecnt[4];		/* coded number of transition times */
47 	uchar	tzh_typecnt[4];		/* coded number of local time types */
48 	uchar	tzh_charcnt[4];		/* coded number of abbr. chars */
49 };
50 
51 /*
52   . . .followed by. . .
53 
54   tzh_timecnt (char [4])s               coded transition times a la time(2)
55   tzh_timecnt (unsigned char)s          types of local time starting at above
56   tzh_typecnt repetitions of
57     one (char [4])                      coded UTC offset in seconds
58     one (unsigned char)                 used to set tm_isdst
59     one (unsigned char)                 that's an abbreviation list index
60   tzh_charcnt (char)s                   '\0'-terminated zone abbreviations
61   tzh_leapcnt repetitions of
62     one (char [4])                      coded leap second transition times
63     one (char [4])                      total correction after above
64   tzh_ttisstdcnt (char)s                indexed by type; if TRUE, transition
65                                         time is standard time, if FALSE,
66                                         transition time is wall clock time
67                                         if absent, transition times are
68                                         assumed to be wall clock time
69   tzh_ttisgmtcnt (char)s                indexed by type; if TRUE, transition
70                                         time is UTC, if FALSE,
71                                         transition time is local time
72                                         if absent, transition times are
73                                         assumed to be local time
74 */
75 
76 /*
77   In the current implementation, we refuse to deal with files that
78   exceed any of the limits below.
79 */
80 
81 #ifndef TZ_MAX_TIMES
82 /*
83   The TZ_MAX_TIMES value below is enough to handle a bit more than a
84   year's worth of solar time (corrected daily to the nearest second) or
85   138 years of Pacific Presidential Election time
86   (where there are three time zone transitions every fourth year).
87 */
88 #define TZ_MAX_TIMES	370
89 #endif /* !defined TZ_MAX_TIMES */
90 
91 #ifndef TZ_MAX_TYPES
92 #ifdef SOLAR
93 #define TZ_MAX_TYPES	256 /* Limited by what (unsigned char)'s can hold */
94 #else
95 /*
96   Must be at least 14 for Europe/Riga as of Jan 12 1995,
97   as noted by Earl Chew <earl@hpato.aus.hp.com>.
98 */
99 #define TZ_MAX_TYPES	20	/* Maximum number of local time types */
100 #endif /* defined SOLAR */
101 #endif /* !defined TZ_MAX_TYPES */
102 
103 #ifndef TZ_MAX_CHARS
104 #define TZ_MAX_CHARS	50	/* Maximum number of abbreviation characters */
105 				/* (limited by what unsigned chars can hold) */
106 #endif /* !defined TZ_MAX_CHARS */
107 
108 #ifndef TZ_MAX_LEAPS
109 #define TZ_MAX_LEAPS	50	/* Maximum number of leap second corrections */
110 #endif /* !defined TZ_MAX_LEAPS */
111 
112 #ifndef TZ_MAX_REV_RANGES
113 #ifdef SOLAR
114 /* Solar (Asia/RiyadhXX) zones need significantly bigger TZ_MAX_REV_RANGES */
115 #define TZ_MAX_REV_RANGES (TZ_MAX_TIMES*2+TZ_MAX_LEAPS*2+2)
116 #else
117 #define TZ_MAX_REV_RANGES (TZ_MAX_TIMES+TZ_MAX_LEAPS+2)
118 #endif
119 #endif
120 
121 #define SECS_PER_MIN	60
122 #define MINS_PER_HOUR	60
123 #define HOURS_PER_DAY	24
124 #define DAYS_PER_WEEK	7
125 #define DAYS_PER_NYEAR	365
126 #define DAYS_PER_LYEAR	366
127 #define SECS_PER_HOUR	(SECS_PER_MIN * MINS_PER_HOUR)
128 #define SECS_PER_DAY	((long) SECS_PER_HOUR * HOURS_PER_DAY)
129 #define MONS_PER_YEAR	12
130 
131 #define TM_YEAR_BASE	1900
132 
133 #define EPOCH_YEAR	1970
134 
135 /*
136   Accurate only for the past couple of centuries,
137   that will probably do.
138 */
139 
140 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
141 
142 #endif
143