Second try to move crc routines to libwsutil.

This time keep the tvb routines in epan.

Now we can use common crc routines outside epan.

svn path=/trunk/; revision=38810

1 files changed, 68 insertions, 0 deletions

diff --git a/wsutil/crc16.h b/wsutil/crc16.h
new file mode 100644
index 0000000000..9ac1928b9e
--- /dev/null
+++ b/wsutil/crc16.h
@@ -0,0 +1,68 @@
+/* crc16.h
+ * Declaration of CRC-16 routines and table
+ *
+ * 2004 Richard van der Hoff <richardv@mxtelecom.com>
+ *
+ * $Id$
+ *
+ * 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.
+*/
+
+#ifndef __CRC16_H__
+#define __CRC16_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/* Calculate the CCITT/ITU/CRC-16 16-bit CRC
+
+   (parameters for this CRC are:
+       Polynomial: x^16 + x^12 + x^5 + 1  (0x1021);
+       Start value 0xFFFF;
+       XOR result with 0xFFFF;
+       First bit is LSB)
+*/
+
+/** Compute CRC16 CCITT checksum of a buffer of data.
+ @param buf The buffer containing the data.
+ @param len The number of bytes to include in the computation.
+ @return The CRC16 CCITT checksum. */
+extern guint16 crc16_ccitt(const guint8 *buf, guint len);
+
+/** Compute CRC16 X.25 CCITT checksum of a buffer of data.
+ @param buf The buffer containing the data.
+ @param len The number of bytes to include in the computation.
+ @return The CRC16 X.25 CCITT checksum. */
+extern guint16 crc16_x25_ccitt(const guint8 *buf, guint len);
+
+/** Compute CRC16 CCITT checksum of a buffer of data.  If computing the
+ *  checksum over multiple buffers and you want to feed the partial CRC16
+ *  back in, remember to take the 1's complement of the partial CRC16 first.
+ @param buf The buffer containing the data.
+ @param len The number of bytes to include in the computation.
+ @param seed The seed to use.
+ @return The CRC16 CCITT checksum (using the given seed). */
+extern guint16 crc16_ccitt_seed(const guint8 *buf, guint len, guint16 seed);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* crc16.h */