wsutil/crc7.h

   1 /** @file
   2  *
   3  * Functions and types for CRC checks.
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  *
  11  * Generated on Wed Jul 11 17:24:57 2012,
  12  * by pycrc v0.7.10, http://www.tty1.net/pycrc/
  13  * using the configuration:
  14  *    Width        = 7
  15  *    Poly         = 0x45
  16  *    XorIn        = 0x00
  17  *    ReflectIn    = False
  18  *    XorOut       = 0x00
  19  *    ReflectOut   = False
  20  *    Algorithm    = table-driven
  21  ****************************************************************************
  22  */
  23 #ifndef __CRC7__H__
  24 #define __CRC7__H__
  25
  26 #include <wireshark.h>
  27
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32
  33 /**
  34  * The definition of the used algorithm.
  35  *****************************************************************************/
  36 #define CRC_ALGO_TABLE_DRIVEN 1
  37
  38 /**
  39  * Calculate the initial crc value.
  40  *
  41  * \return     The initial crc value.
  42  *****************************************************************************/
  43 static inline uint8_t crc7init(void)
  44 {
  45     return 0x00 << 1;
  46 }
  47
  48
  49 /**
  50  * Update the crc value with new data.
  51  *
  52  * \param crc      The current crc value.
  53  * \param data     Pointer to a buffer of \a data_len bytes.
  54  * \param data_len Number of bytes in the \a data buffer.
  55  * \return         The updated crc value.
  56  *****************************************************************************/
  57 WS_DLL_PUBLIC uint8_t crc7update(uint8_t crc, const unsigned char *data, int data_len);
  58
  59
  60 /**
  61  * Calculate the final crc value.
  62  *
  63  * \param crc  The current crc value.
  64  * \return     The final crc value.
  65  *****************************************************************************/
  66 static inline uint8_t crc7finalize(uint8_t crc)
  67 {
  68     return (crc >> 1) ^ 0x00;
  69 }
  70
  71
  72 #ifdef __cplusplus
  73 }           /* closing brace for extern "C" */
  74 #endif
  75
  76 #endif      /* __CRC7__H__ */