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authorBill Fenner <fenner@FreeBSD.org>1998-09-15 19:36:32 +0000
committerBill Fenner <fenner@FreeBSD.org>1998-09-15 19:36:32 +0000
commit4644f044b29b71b385396356b7cbf92b09e67628 (patch)
tree6bd786e664682d3877b9cca3efa525ac67d8e005 /contrib/tcpdump/gmt2local.c
parent4de76e31371f636d15e4005d6bed5755adb4c393 (diff)
downloadsrc-4644f044b29b71b385396356b7cbf92b09e67628.tar.gz
src-4644f044b29b71b385396356b7cbf92b09e67628.zip
Virgin import of LBL tcpdump v3.4
Notes
Notes: svn path=/vendor/tcpdump/dist/; revision=39297
Diffstat (limited to 'contrib/tcpdump/gmt2local.c')
-rw-r--r--contrib/tcpdump/gmt2local.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/contrib/tcpdump/gmt2local.c b/contrib/tcpdump/gmt2local.c
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+/*
+ * Copyright (c) 1997
+ * 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: (1) source code distributions
+ * retain the above copyright notice and this paragraph in its entirety, (2)
+ * distributions including binary code include the above copyright notice and
+ * this paragraph in its entirety in the documentation or other materials
+ * provided with the distribution, and (3) all advertising materials mentioning
+ * features or use of this software display the following acknowledgement:
+ * ``This product includes software developed by the University of California,
+ * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#ifndef lint
+static const char rcsid[] =
+ "@(#) $Header: gmt2local.c,v 1.2 97/01/23 22:31:25 leres Exp $ (LBL)";
+#endif
+
+#include <sys/types.h>
+#include <sys/time.h>
+
+#include <stdio.h>
+#ifdef TIME_WITH_SYS_TIME
+#include <time.h>
+#endif
+
+#include "gnuc.h"
+#ifdef HAVE_OS_PROTO_H
+#include "os-proto.h"
+#endif
+
+#include "gmt2local.h"
+
+/*
+ * Returns the difference between gmt and local time in seconds.
+ * Use gmtime() and localtime() to keep things simple.
+ */
+int32_t
+gmt2local(time_t t)
+{
+ register int dt, dir;
+ register struct tm *gmt, *loc;
+ struct tm sgmt;
+
+ if (t == 0)
+ t = time(NULL);
+ gmt = &sgmt;
+ *gmt = *gmtime(&t);
+ loc = localtime(&t);
+ dt = (loc->tm_hour - gmt->tm_hour) * 60 * 60 +
+ (loc->tm_min - gmt->tm_min) * 60;
+
+ /*
+ * If the year or julian day is different, we span 00:00 GMT
+ * and must add or subtract a day. Check the year first to
+ * avoid problems when the julian day wraps.
+ */
+ dir = loc->tm_year - gmt->tm_year;
+ if (dir == 0)
+ dir = loc->tm_yday - gmt->tm_yday;
+ dt += dir * 24 * 60 * 60;
+
+ return (dt);
+}