14887Schin /*********************************************************************** 24887Schin * * 34887Schin * This software is part of the ast package * 4*8462SApril.Chin@Sun.COM * Copyright (c) 1985-2008 AT&T Intellectual Property * 54887Schin * and is licensed under the * 64887Schin * Common Public License, Version 1.0 * 7*8462SApril.Chin@Sun.COM * by AT&T Intellectual Property * 84887Schin * * 94887Schin * A copy of the License is available at * 104887Schin * http://www.opensource.org/licenses/cpl1.0.txt * 114887Schin * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * 124887Schin * * 134887Schin * Information and Software Systems Research * 144887Schin * AT&T Research * 154887Schin * Florham Park NJ * 164887Schin * * 174887Schin * Glenn Fowler <gsf@research.att.com> * 184887Schin * David Korn <dgk@research.att.com> * 194887Schin * Phong Vo <kpv@research.att.com> * 204887Schin * * 214887Schin ***********************************************************************/ 224887Schin #pragma prototyped 234887Schin /* 244887Schin * Glenn Fowler 254887Schin * AT&T Research 264887Schin * 274887Schin * time_t conversion support 284887Schin */ 294887Schin 304887Schin #include <tm.h> 314887Schin 324887Schin /* 334887Schin * use one of the 14 equivalent calendar years to determine 344887Schin * daylight savings time for future years beyond the range 354887Schin * of the local system (via tmxmake()) 364887Schin */ 374887Schin 384887Schin static const short equiv[] = 394887Schin { 404887Schin 2006, 2012, 414887Schin 2001, 2024, 424887Schin 2002, 2008, 434887Schin 2003, 2020, 444887Schin 2009, 2004, 454887Schin 2010, 2016, 464887Schin 2005, 2000, 474887Schin }; 484887Schin 494887Schin /* 504887Schin * return the circa 2000 equivalent calendar year for tm 514887Schin */ 524887Schin 534887Schin int 544887Schin tmequiv(Tm_t* tm) 554887Schin { 564887Schin return tm->tm_year < (2038 - 1900) ? (tm->tm_year + 1900) : equiv[tm->tm_wday + tmisleapyear(tm->tm_year)]; 574887Schin } 58