wsutil/crc16-plain.h

   1 /** @file
   2  * http://www.tty1.net/pycrc/faq_en.html#code-ownership
   3  *
   4  * Wireshark - Network traffic analyzer
   5  * By Gerald Combs <gerald@wireshark.org>
   6  * Copyright 1998 Gerald Combs
   7  *
   8  * SPDX-License-Identifier: GPL-2.0-or-later
   9  */
  10
  11 /**
  12  * \file crc16-plain.h
  13  * Functions and types for CRC checks.
  14  *
  15  * Generated on Wed Mar 18 14:12:15 2009,
  16  * by pycrc v0.7, http://www.tty1.net/pycrc/
  17  * using the configuration:
  18  *    Width        = 16
  19  *    Poly         = 0x8005
  20  *    XorIn        = 0x0000
  21  *    ReflectIn    = True
  22  *    XorOut       = 0x0000
  23  *    ReflectOut   = True
  24  *    Algorithm    = table-driven
  25  *    Direct       = True
  26  *
  27  * Modified 2009-03-16 not to include <stdint.h> as our Win32 environment
  28  * appears not to have it; we're using GLib types, instead.
  29  *****************************************************************************/
  30 #ifndef __CRC____PLAIN_H__
  31 #define __CRC____PLAIN_H__
  32
  33 #include <stddef.h>
  34 #include <stdint.h>
  35
  36 #include "ws_symbol_export.h"
  37
  38 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 /**
  43  * The definition of the used algorithm.
  44  *****************************************************************************/
  45 #define CRC_ALGO_TABLE_DRIVEN 1
  46
  47 /**
  48  * The type of the CRC values.
  49  *
  50  * This type must be big enough to contain at least 16 bits.
  51  *****************************************************************************/
  52 typedef uint16_t crc16_plain_t;
  53
  54 /**
  55  * Reflect all bits of a \a data word of \a data_len bytes.
  56  *
  57  * \param data         The data word to be reflected.
  58  * \param data_len     The width of \a data expressed in number of bits.
  59  * \return     The reflected data.
  60  *****************************************************************************/
  61 long crc16_plain_reflect(long data, size_t data_len);
  62
  63 /**
  64  * Calculate the initial crc value.
  65  *
  66  * \return     The initial crc value.
  67  *****************************************************************************/
  68 static inline crc16_plain_t crc16_plain_init(void)
  69 {
  70     return 0x0000;
  71 }
  72
  73 /**
  74  * Update the crc value with new data.
  75  *
  76  * \param crc      The current crc value.
  77  * \param data     Pointer to a buffer of \a data_len bytes.
  78  * \param data_len Number of bytes in the \a data buffer.
  79  * \return         The updated crc value.
  80  *****************************************************************************/
  81 WS_DLL_PUBLIC
  82 crc16_plain_t crc16_plain_update(crc16_plain_t crc, const unsigned char *data, size_t data_len);
  83
  84 /**
  85  * Calculate the final crc value.
  86  *
  87  * \param crc  The current crc value.
  88  * \return     The final crc value.
  89  *****************************************************************************/
  90 static inline crc16_plain_t crc16_plain_finalize(crc16_plain_t crc)
  91 {
  92     return crc ^ 0x0000;
  93 }
  94
  95 /* Generated on Tue Jul 24 09:08:46 2012,
  96  * by pycrc v0.7.10, http://www.tty1.net/pycrc/
  97  * using the configuration:
  98  *    Width        = 16
  99  *    Poly         = 0x8005
 100  *    XorIn        = 0x0000
 101  *    ReflectIn    = False
 102  *    XorOut       = 0x0000
 103  *    ReflectOut   = False
 104  *    Algorithm    = table-driven
 105  *
 106  * Calculate the crc-16 (x^16 + x^15 + x^2 + 1) value for data. Note that this
 107  * CRC is not equal to crc16_plain.
 108  *
 109  * \param data     Pointer to a buffer of \a data_len bytes.
 110  * \param data_len Number of bytes in the \a data buffer.
 111  * \return         The crc value.
 112  *****************************************************************************/
 113 WS_DLL_PUBLIC
 114 uint16_t crc16_8005_noreflect_noxor(const uint8_t *data, uint64_t data_len);
 115
 116
 117 #ifdef __cplusplus
 118 }           /* closing brace for extern "C" */
 119 #endif
 120
 121 #endif      /* __CRC____PLAIN_H__ */