[mirror_qemu.git] / include / qemu / crc-ccitt.h

/*
 * CRC16 (CCITT) Checksum Algorithm
 *
 * Copyright (c) 2021 Wind River Systems, Inc.
 *
 * Author:
 *   Bin Meng <bin.meng@windriver.com>
 *
 * From Linux kernel v5.10 include/linux/crc-ccitt.h
 *
 * SPDX-License-Identifier: GPL-2.0
 */

#ifndef CRC_CCITT_H
#define CRC_CCITT_H

extern uint16_t const crc_ccitt_table[256];
extern uint16_t const crc_ccitt_false_table[256];

uint16_t crc_ccitt(uint16_t crc, const uint8_t *buffer, size_t len);
uint16_t crc_ccitt_false(uint16_t crc, const uint8_t *buffer, size_t len);

static inline uint16_t crc_ccitt_byte(uint16_t crc, const uint8_t c)
{
    return (crc >> 8) ^ crc_ccitt_table[(crc ^ c) & 0xff];
}

static inline uint16_t crc_ccitt_false_byte(uint16_t crc, const uint8_t c)
{
    return (crc << 8) ^ crc_ccitt_false_table[(crc >> 8) ^ c];
}

#endif /* CRC_CCITT_H */
Commit	Line	Data
0b73ce30 BM	1	/*
	2	* CRC16 (CCITT) Checksum Algorithm
	3	*
	4	* Copyright (c) 2021 Wind River Systems, Inc.
	5	*
	6	* Author:
	7	* Bin Meng <bin.meng@windriver.com>
	8	*
	9	* From Linux kernel v5.10 include/linux/crc-ccitt.h
	10	*
	11	* SPDX-License-Identifier: GPL-2.0
	12	*/
	13
9c092804 MA	14	#ifndef CRC_CCITT_H
9c092804 MA	15	#define CRC_CCITT_H
0b73ce30 BM	16
	17	extern uint16_t const crc_ccitt_table[256];
	18	extern uint16_t const crc_ccitt_false_table[256];
	19
f703f1ef PMD	20	uint16_t crc_ccitt(uint16_t crc, const uint8_t *buffer, size_t len);
f703f1ef PMD	21	uint16_t crc_ccitt_false(uint16_t crc, const uint8_t *buffer, size_t len);
0b73ce30 BM	22
	23	static inline uint16_t crc_ccitt_byte(uint16_t crc, const uint8_t c)
	24	{
	25	return (crc >> 8) ^ crc_ccitt_table[(crc ^ c) & 0xff];
	26	}
	27
	28	static inline uint16_t crc_ccitt_false_byte(uint16_t crc, const uint8_t c)
	29	{
	30	return (crc << 8) ^ crc_ccitt_false_table[(crc >> 8) ^ c];
	31	}
	32
9c092804	33	#endif /* CRC_CCITT_H */