wsutil/crc7.h

   1 /*
   2  * crc7.h
   3  *
   4  * $Id$
   5  *
   6  * Functions and types for CRC checks.
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  25  *
  26  * Generated on Wed Jul 11 17:24:57 2012,
  27  * by pycrc v0.7.10, http://www.tty1.net/pycrc/
  28  * using the configuration:
  29  *    Width        = 7
  30  *    Poly         = 0x45
  31  *    XorIn        = 0x00
  32  *    ReflectIn    = False
  33  *    XorOut       = 0x00
  34  *    ReflectOut   = False
  35  *    Algorithm    = table-driven
  36  ****************************************************************************
  37  */
  38 #ifndef __CRC7__H__
  39 #define __CRC7__H__
  40
  41 #include "ws_symbol_export.h"
  42
  43 #ifdef __cplusplus
  44 extern "C" {
  45 #endif
  46
  47
  48 /**
  49  * The definition of the used algorithm.
  50  *****************************************************************************/
  51 #define CRC_ALGO_TABLE_DRIVEN 1
  52
  53 /**
  54  * Calculate the initial crc value.
  55  *
  56  * \return     The initial crc value.
  57  *****************************************************************************/
  58 static inline guint8 crc7init(void)
  59 {
  60     return 0x00 << 1;
  61 }
  62
  63
  64 /**
  65  * Update the crc value with new data.
  66  *
  67  * \param crc      The current crc value.
  68  * \param data     Pointer to a buffer of \a data_len bytes.
  69  * \param data_len Number of bytes in the \a data buffer.
  70  * \return         The updated crc value.
  71  *****************************************************************************/
  72 WS_DLL_PUBLIC guint8 crc7update(guint8 crc, const unsigned char *data, int data_len);
  73
  74
  75 /**
  76  * Calculate the final crc value.
  77  *
  78  * \param crc  The current crc value.
  79  * \return     The final crc value.
  80  *****************************************************************************/
  81 static inline guint8 crc7finalize(guint8 crc)
  82 {
  83     return (crc >> 1) ^ 0x00;
  84 }
  85
  86
  87 #ifdef __cplusplus
  88 }           /* closing brace for extern "C" */
  89 #endif
  90
  91 #endif      /* __CRC7__H__ */