Move all crc routines to libwsutil.

This way we can use the crc routines in wiretap.

svn path=/trunk/; revision=38800

1 files changed, 53 insertions, 0 deletions

diff --git a/wsutil/crc6.c b/wsutil/crc6.c
new file mode 100644
index 0000000000..333a1a51cd
--- /dev/null
+++ b/wsutil/crc6.c
@@ -0,0 +1,53 @@
+/*
+ *  crc6.c
+ *  
+ * $Id$
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <glib.h>
+#include "crc6.h"
+
+
+guint16 update_crc6_by_bytes(guint16 crc6, guint8 byte1, guint8 byte2) {
+    int bit;
+    guint32 remainder = ( byte1<<8 | byte2 ) << 6;
+    guint32 polynomial = 0x6F << 15;
+	
+    for (bit = 15;
+		 bit >= 0;
+		 --bit)
+    {
+        if (remainder & (0x40 << bit))
+        {
+            remainder ^= polynomial;
+        }
+        polynomial >>= 1;
+    }
+	
+    return (guint16)(remainder ^ crc6);
+}
+
+