42 lines
612 B
C++
42 lines
612 B
C++
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#include <stddef.h>
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#include <stdint.h>
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#include "crc8hondak.h"
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static inline uint8_t crc_init(void)
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{
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return 0xff;
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}
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static inline uint8_t crc_next(uint8_t crc, uint8_t data)
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{
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uint8_t eor;
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unsigned int i = 8;
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crc ^= data;
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do {
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/* This might produce branchless code */
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eor = crc & 1 ? 0xb8 : 0;
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crc >>= 1;
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crc ^= eor;
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} while (--i);
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return crc;
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}
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static inline uint8_t crc_final(uint8_t crc)
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{
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return ~crc;
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}
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uint8_t crc_hondak_calc(const uint8_t *data, size_t len)
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{
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uint8_t crc = crc_init();
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if (len) do {
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crc = crc_next(crc, *data++);
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} while (--len);
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return crc_final(crc);
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}
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