/* * 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. */ #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); }