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diff --git a/lib/libc/gen/timezone.c b/lib/libc/gen/timezone.c
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+/* $NetBSD: timezone.c,v 1.5 1995/02/27 05:54:24 cgd Exp $ */
+
+/*
+ * Copyright (c) 1987, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+#if 0
+static char sccsid[] = "@(#)timezone.c 8.1 (Berkeley) 6/4/93";
+#else
+static char rcsid[] = "$NetBSD: timezone.c,v 1.5 1995/02/27 05:54:24 cgd Exp $";
+#endif
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <tzfile.h>
+
+char *_tztab();
+
+/*
+ * timezone --
+ * The arguments are the number of minutes of time you are westward
+ * from Greenwich and whether DST is in effect. It returns a string
+ * giving the name of the local timezone. Should be replaced, in the
+ * application code, by a call to localtime.
+ */
+
+static char czone[TZ_MAX_CHARS]; /* space for zone name */
+
+char *
+timezone(zone, dst)
+ int zone,
+ dst;
+{
+ register char *beg,
+ *end;
+
+ if (beg = getenv("TZNAME")) { /* set in environment */
+ if (end = strchr(beg, ',')) { /* "PST,PDT" */
+ if (dst)
+ return(++end);
+ *end = '\0';
+ (void)strncpy(czone,beg,sizeof(czone) - 1);
+ czone[sizeof(czone) - 1] = '\0';
+ *end = ',';
+ return(czone);
+ }
+ return(beg);
+ }
+ return(_tztab(zone,dst)); /* default: table or created zone */
+}
+
+static struct zone {
+ int offset;
+ char *stdzone;
+ char *dlzone;
+} zonetab[] = {
+ -1*60, "MET", "MET DST", /* Middle European */
+ -2*60, "EET", "EET DST", /* Eastern European */
+ 4*60, "AST", "ADT", /* Atlantic */
+ 5*60, "EST", "EDT", /* Eastern */
+ 6*60, "CST", "CDT", /* Central */
+ 7*60, "MST", "MDT", /* Mountain */
+ 8*60, "PST", "PDT", /* Pacific */
+#ifdef notdef
+ /* there's no way to distinguish this from WET */
+ 0, "GMT", 0, /* Greenwich */
+#endif
+ 0*60, "WET", "WET DST", /* Western European */
+ -10*60, "EST", "EST", /* Aust: Eastern */
+ -10*60+30, "CST", "CST", /* Aust: Central */
+ -8*60, "WST", 0, /* Aust: Western */
+ -1
+};
+
+/*
+ * _tztab --
+ * check static tables or create a new zone name; broken out so that
+ * we can make a guess as to what the zone is if the standard tables
+ * aren't in place in /etc. DO NOT USE THIS ROUTINE OUTSIDE OF THE
+ * STANDARD LIBRARY.
+ */
+char *
+_tztab(zone,dst)
+ register int zone;
+ int dst;
+{
+ register struct zone *zp;
+ register char sign;
+
+ for (zp = zonetab; zp->offset != -1;++zp) /* static tables */
+ if (zp->offset == zone) {
+ if (dst && zp->dlzone)
+ return(zp->dlzone);
+ if (!dst && zp->stdzone)
+ return(zp->stdzone);
+ }
+
+ if (zone < 0) { /* create one */
+ zone = -zone;
+ sign = '+';
+ }
+ else
+ sign = '-';
+ (void)sprintf(czone,"GMT%c%d:%02d",sign,zone / 60,zone % 60);
+ return(czone);
+}