Imported Upstream version 93u+upstream

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diff --git a/src/lib/libast/tm/tmequiv.c b/src/lib/libast/tm/tmequiv.c
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+/***********************************************************************
+*                                                                      *
+*               This software is part of the ast package               *
+*          Copyright (c) 1985-2011 AT&T Intellectual Property          *
+*                      and is licensed under the                       *
+*                 Eclipse Public License, Version 1.0                  *
+*                    by AT&T Intellectual Property                     *
+*                                                                      *
+*                A copy of the License is available at                 *
+*          http://www.eclipse.org/org/documents/epl-v10.html           *
+*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
+*                                                                      *
+*              Information and Software Systems Research               *
+*                            AT&T Research                             *
+*                           Florham Park NJ                            *
+*                                                                      *
+*                 Glenn Fowler <gsf@research.att.com>                  *
+*                  David Korn <dgk@research.att.com>                   *
+*                   Phong Vo <kpv@research.att.com>                    *
+*                                                                      *
+***********************************************************************/
+#pragma prototyped
+/*
+ * Glenn Fowler
+ * AT&T Research
+ *
+ * time_t conversion support
+ */
+
+#include <tm.h>
+
+/*
+ * use one of the 14 equivalent calendar years to determine
+ * daylight savings time for future years beyond the range
+ * of the local system (via tmxtm())
+ */
+
+static const short equiv[] =
+{
+	2006, 2012,
+	2001, 2024,
+	2002, 2008,
+	2003, 2020,
+	2009, 2004,
+	2010, 2016,
+	2005, 2000,
+};
+
+/*
+ * return the circa 2000 equivalent calendar year for tm
+ */
+
+int
+tmequiv(Tm_t* tm)
+{
+	return tm->tm_year < (2038 - 1900) ? (tm->tm_year + 1900) : equiv[tm->tm_wday + tmisleapyear(tm->tm_year)];
+}