2 * Copyright (c) 1987, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)timezone.c 8.1 (Berkeley) 6/4/93";
36 #endif /* LIBC_SCCS and not lint */
38 #include <sys/types.h>
43 #define TZ_MAX_CHARS 255
49 * The arguments are the number of minutes of time you are westward
50 * from Greenwich and whether DST is in effect. It returns a string
51 * giving the name of the local timezone. Should be replaced, in the
52 * application code, by a call to localtime.
55 static char czone[TZ_MAX_CHARS]; /* space for zone name */
65 if ( (beg = getenv("TZNAME")) ) { /* set in environment */
66 if ( (end = index(beg, ',')) ) {/* "PST,PDT" */
70 (void)strncpy(czone,beg,sizeof(czone) - 1);
71 czone[sizeof(czone) - 1] = '\0';
77 return(_tztab(zone,dst)); /* default: table or created zone */
85 {-1*60, "MET", "MET DST"}, /* Middle European */
86 {-2*60, "EET", "EET DST"}, /* Eastern European */
87 {4*60, "AST", "ADT"}, /* Atlantic */
88 {5*60, "EST", "EDT"}, /* Eastern */
89 {6*60, "CST", "CDT"}, /* Central */
90 {7*60, "MST", "MDT"}, /* Mountain */
91 {8*60, "PST", "PDT"}, /* Pacific */
93 /* there's no way to distinguish this from WET */
94 {0, "GMT", 0}, /* Greenwich */
96 {0*60, "WET", "WET DST"}, /* Western European */
97 {-10*60,"EST", "EST"}, /* Aust: Eastern */
98 {-10*60+30,"CST", "CST"}, /* Aust: Central */
99 {-8*60, "WST", 0}, /* Aust: Western */
105 * check static tables or create a new zone name; broken out so that
106 * we can make a guess as to what the zone is if the standard tables
107 * aren't in place in /etc. DO NOT USE THIS ROUTINE OUTSIDE OF THE
115 register struct zone *zp;
118 for (zp = zonetab; zp->offset != -1;++zp) /* static tables */
119 if (zp->offset == zone) {
120 if (dst && zp->dlzone)
122 if (!dst && zp->stdzone)
126 if (zone < 0) { /* create one */
132 (void)snprintf(czone, sizeof(czone),
133 "GMT%c%d:%02d",sign,zone / 60,zone % 60);