/* * 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)static char sccsid[] = "@(#)timezone.c	8.1 (Berkeley) 6/4/93";#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 = index(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);}