crc.h

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/****************************************************************************
 *
 *   Copyright (c) 2015 PX4 Development Team. All rights reserved.
 *       Author: Ben Dyer <ben_dyer@mac.com>
 *               Pavel Kirienko <pavel.kirienko@zubax.com>
 *               David Sidrane <david_s5@nscdg.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name PX4 nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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 * POSSIBILITY OF SUCH DAMAGE.
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 ****************************************************************************/

#pragma once

/****************************************************************************
 * Included Files
 ****************************************************************************/
/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
#define CRC16_INITIAL           0xFFFFu
#define CRC16_OUTPUT_XOR        0x0000u
#define CRC64_INITIAL           0xFFFFFFFFFFFFFFFFull
#define CRC64_OUTPUT_XOR        0xFFFFFFFFFFFFFFFFull

/****************************************************************************
 * Public Type Definitions
 ****************************************************************************/

/****************************************************************************
 * Global Variables
 ****************************************************************************/

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/
/****************************************************************************
 * Name: crc16_add
 *
 * Description:
 *   Use to calculates a CRC-16-CCITT using the polynomial of
 *   0x1021 by adding a value successive values.
 *
 * Input Parameters:
 *    crc   - The running total of the crc 16
 *    value - The value to add
 *
 * Returned Value:
 *   The current crc16 with the value processed.
 *
 ****************************************************************************/

uint16_t crc16_add(uint16_t crc, uint8_t value);

/****************************************************************************
 * Name: crc16_signature
 *
 * Description:
 *   Calculates a CRC-16-CCITT using the crc16_add
 *   function
 *
 * Input Parameters:
 *    initial - The Initial value to uses as the crc's starting point
 *    length  - The number of bytes to add to the crc
 *    bytes   - A pointer to any array of length bytes
 *
 * Returned Value:
 *   The crc16 of the array of bytes
 *
 ****************************************************************************/

uint16_t crc16_signature(uint16_t initial, size_t length,
             const uint8_t *bytes);

/****************************************************************************
 * Name: crc64_add_word
 *
 * Description:
 *   Calculates a CRC-64-WE using the polynomial of 0x42F0E1EBA9EA3693
 *   See http://reveng.sourceforge.net/crc-catalogue/17plus.htm#crc.cat-bits.64
 *   Check: 0x62EC59E3F1A4F00A
 *
 * Input Parameters:
 *    crc   - The running total of the crc 64
 *    value - The value to add
 *
 * Returned Value:
 *   The current crc64 with the value processed.
 *
 ****************************************************************************/

uint64_t crc64_add_word(uint64_t crc, uint32_t value);