11993Swnj /* 230682Sbostic * Copyright (c) 1987 Regents of the University of California. 321365Sdist * All rights reserved. The Berkeley software License Agreement 421365Sdist * specifies the terms and conditions for redistribution. 521365Sdist */ 621365Sdist 730683Sbostic #if defined(LIBC_SCCS) && !defined(lint) 8*30820Skarels static char sccsid[] = "@(#)timezone.c 5.6 (Berkeley) 04/06/87"; 930683Sbostic #endif LIBC_SCCS and not lint 1021365Sdist 1130682Sbostic #include <sys/types.h> 1230682Sbostic #include <sys/time.h> 1330682Sbostic #include <stdio.h> 1430682Sbostic #include <tzfile.h> 1530682Sbostic 1621365Sdist /* 1730682Sbostic * timezone -- 1830682Sbostic * The arguments are the number of minutes of time you are westward 1930682Sbostic * from Greenwich and whether DST is in effect. It returns a string 2030682Sbostic * giving the name of the local timezone. Should be replaced, in the 2130682Sbostic * application code, by a call to localtime. 221993Swnj */ 231993Swnj 2430682Sbostic static char czone[TZ_MAX_CHARS]; /* space for zone name */ 2530682Sbostic 2630682Sbostic char * 2730682Sbostic timezone(zone, dst) 2830682Sbostic int zone, 2930682Sbostic dst; 3030682Sbostic { 3130682Sbostic register char *beg, 3230682Sbostic *end; 33*30820Skarels char *getenv(), *index(), *strncpy(), *_tztab(); 3430682Sbostic 3530682Sbostic if (beg = getenv("TZNAME")) { /* set in environment */ 3630682Sbostic if (end = index(beg, ',')) { /* "PST,PDT" */ 3730682Sbostic if (dst) 3830682Sbostic return(++end); 3930682Sbostic *end = '\0'; 4030682Sbostic (void)strncpy(czone,beg,sizeof(czone) - 1); 4130682Sbostic czone[sizeof(czone) - 1] = '\0'; 4230682Sbostic *end = ','; 4330682Sbostic return(czone); 4430682Sbostic } 4530682Sbostic return(beg); 4630682Sbostic } 47*30820Skarels return(_tztab(zone,dst)); /* default: table or created zone */ 4830682Sbostic } 4930682Sbostic 501993Swnj static struct zone { 511993Swnj int offset; 521993Swnj char *stdzone; 531993Swnj char *dlzone; 541993Swnj } zonetab[] = { 5530682Sbostic -1*60, "MET", "MET DST", /* Middle European */ 5630682Sbostic -2*60, "EET", "EET DST", /* Eastern European */ 5730682Sbostic 4*60, "AST", "ADT", /* Atlantic */ 5830682Sbostic 5*60, "EST", "EDT", /* Eastern */ 5930682Sbostic 6*60, "CST", "CDT", /* Central */ 6030682Sbostic 7*60, "MST", "MDT", /* Mountain */ 6130682Sbostic 8*60, "PST", "PDT", /* Pacific */ 6213877Ssam #ifdef notdef 6313877Ssam /* there's no way to distinguish this from WET */ 6430682Sbostic 0, "GMT", 0, /* Greenwich */ 6513877Ssam #endif 6630682Sbostic 0*60, "WET", "WET DST", /* Western European */ 6730682Sbostic -10*60, "EST", "EST", /* Aust: Eastern */ 6830682Sbostic -10*60+30, "CST", "CST", /* Aust: Central */ 6930682Sbostic -8*60, "WST", 0, /* Aust: Western */ 701993Swnj -1 711993Swnj }; 721993Swnj 7330682Sbostic /* 74*30820Skarels * _tztab -- 7530682Sbostic * check static tables or create a new zone name; broken out so that 7630682Sbostic * we can make a guess as to what the zone is if the standard tables 7730682Sbostic * aren't in place in /etc. DO NOT USE THIS ROUTINE OUTSIDE OF THE 7830682Sbostic * STANDARD LIBRARY. 7930682Sbostic */ 8030682Sbostic char * 8130713Sbostic _tztab(zone,dst) 8230682Sbostic register int zone; 8330682Sbostic int dst; 841993Swnj { 8530682Sbostic register struct zone *zp; 8630682Sbostic register char sign; 871993Swnj 8830682Sbostic for (zp = zonetab; zp->offset != -1;++zp) /* static tables */ 8930682Sbostic if (zp->offset == zone) { 901993Swnj if (dst && zp->dlzone) 911993Swnj return(zp->dlzone); 921993Swnj if (!dst && zp->stdzone) 931993Swnj return(zp->stdzone); 941993Swnj } 9530682Sbostic 9630682Sbostic if (zone < 0) { /* create one */ 971993Swnj zone = -zone; 9830682Sbostic sign = '+'; 9930682Sbostic } 10030682Sbostic else 10130682Sbostic sign = '-'; 10230682Sbostic (void)sprintf(czone,"GMT%c%d:%02d",sign,zone / 60,zone % 60); 1031993Swnj return(czone); 1041993Swnj } 105