[apple/libc.git] / gen / FreeBSD / timezone.c

/*
 * 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.
 * 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.
 */

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wstrict-prototypes"

#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/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libc/gen/timezone.c,v 1.6 2007/01/09 00:27:55 imp Exp $");

#include <sys/types.h>
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define TZ_MAX_CHARS 255

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;
{
	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)
	int	zone;
	int	dst;
{
	struct zone	*zp;
	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)snprintf(czone, sizeof(czone),
	    "GMT%c%d:%02d",sign,zone / 60,zone % 60);
	return(czone);
}
#pragma clang diagnostic pop
Commit	Line	Data
e9ce8d39 A	1	/*
	2	* Copyright (c) 1987, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	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.
e9ce8d39 A	13	* 4. Neither the name of the University nor the names of its contributors
	14	* may be used to endorse or promote products derived from this software
	15	* without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	18	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	19	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	20	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	21	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	22	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	23	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	25	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	26	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	27	* SUCH DAMAGE.
	28	*/
	29
70ad1dc8 A	30	#pragma clang diagnostic push
	31	#pragma clang diagnostic ignored "-Wstrict-prototypes"
	32
9385eb3d A	33	#if defined(LIBC_SCCS) && !defined(lint)
	34	static char sccsid[] = "@(#)timezone.c 8.1 (Berkeley) 6/4/93";
	35	#endif /* LIBC_SCCS and not lint */
	36	#include <sys/cdefs.h>
1f2f436a	37	__FBSDID("$FreeBSD: src/lib/libc/gen/timezone.c,v 1.6 2007/01/09 00:27:55 imp Exp $");
e9ce8d39 A	38
	39	#include <sys/types.h>
	40	#include <sys/time.h>
	41	#include <stdio.h>
	42	#include <stdlib.h>
	43	#include <string.h>
9385eb3d	44	#define TZ_MAX_CHARS 255
e9ce8d39 A	45
	46	char *_tztab();
	47
	48	/*
	49	* timezone --
	50	* The arguments are the number of minutes of time you are westward
	51	* from Greenwich and whether DST is in effect. It returns a string
	52	* giving the name of the local timezone. Should be replaced, in the
	53	* application code, by a call to localtime.
	54	*/
	55
	56	static char czone[TZ_MAX_CHARS]; /* space for zone name */
	57
	58	char *
	59	timezone(zone, dst)
	60	int zone,
	61	dst;
	62	{
9385eb3d	63	char *beg,
e9ce8d39 A	64	*end;
e9ce8d39 A	65
9385eb3d A	66	if ( (beg = getenv("TZNAME")) ) { /* set in environment */
9385eb3d A	67	if ( (end = index(beg, ',')) ) {/* "PST,PDT" */
e9ce8d39 A	68	if (dst)
	69	return(++end);
	70	*end = '\0';
	71	(void)strncpy(czone,beg,sizeof(czone) - 1);
	72	czone[sizeof(czone) - 1] = '\0';
	73	*end = ',';
	74	return(czone);
	75	}
	76	return(beg);
	77	}
	78	return(_tztab(zone,dst)); /* default: table or created zone */
	79	}
	80
	81	static struct zone {
	82	int offset;
	83	char *stdzone;
	84	char *dlzone;
	85	} zonetab[] = {
9385eb3d A	86	{-160, "MET", "MET DST"}, / Middle European */
	87	{-260, "EET", "EET DST"}, / Eastern European */
	88	{460, "AST", "ADT"}, / Atlantic */
	89	{560, "EST", "EDT"}, / Eastern */
	90	{660, "CST", "CDT"}, / Central */
	91	{760, "MST", "MDT"}, / Mountain */
	92	{860, "PST", "PDT"}, / Pacific */
e9ce8d39 A	93	#ifdef notdef
e9ce8d39 A	94	/* there's no way to distinguish this from WET */
9385eb3d	95	{0, "GMT", 0}, /* Greenwich */
e9ce8d39	96	#endif
9385eb3d A	97	{060, "WET", "WET DST"}, / Western European */
	98	{-1060,"EST", "EST"}, / Aust: Eastern */
	99	{-1060+30,"CST", "CST"}, / Aust: Central */
	100	{-860, "WST", 0}, / Aust: Western */
	101	{-1}
e9ce8d39 A	102	};
	103
	104	/*
	105	* _tztab --
	106	* check static tables or create a new zone name; broken out so that
	107	* we can make a guess as to what the zone is if the standard tables
	108	* aren't in place in /etc. DO NOT USE THIS ROUTINE OUTSIDE OF THE
	109	* STANDARD LIBRARY.
	110	*/
	111	char *
	112	_tztab(zone,dst)
9385eb3d	113	int zone;
e9ce8d39 A	114	int dst;
e9ce8d39 A	115	{
9385eb3d A	116	struct zone *zp;
9385eb3d A	117	char sign;
e9ce8d39 A	118
	119	for (zp = zonetab; zp->offset != -1;++zp) /* static tables */
	120	if (zp->offset == zone) {
	121	if (dst && zp->dlzone)
	122	return(zp->dlzone);
	123	if (!dst && zp->stdzone)
	124	return(zp->stdzone);
	125	}
	126
	127	if (zone < 0) { /* create one */
	128	zone = -zone;
	129	sign = '+';
	130	}
	131	else
	132	sign = '-';
9385eb3d A	133	(void)snprintf(czone, sizeof(czone),
9385eb3d A	134	"GMT%c%d:%02d",sign,zone / 60,zone % 60);
e9ce8d39 A	135	return(czone);
e9ce8d39 A	136	}
70ad1dc8	137	#pragma clang diagnostic pop