numam-spdk/lib/util/crc16.c

/*-
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#include "spdk/crc16.h"

uint16_t
spdk_crc16_t10dif(uint16_t init_crc, const void *buf, size_t len)
{
	uint32_t j, rem;
	const uint8_t *data = (const uint8_t *)buf;
	size_t i;

	uint16_t poly = SPDK_T10DIF_CRC16_POLYNOMIAL;

	rem = init_crc;

	for (i = 0; i < len; i++) {
		rem = rem ^ (data[i] << 8);
		for (j = 0; j < 8; j++) {
			rem = rem << 1;
			rem = (rem & 0x10000) ? rem ^ poly : rem;
		}
	}
	return (uint16_t)rem;
}

uint16_t
spdk_crc16_t10dif_copy(uint16_t init_crc, uint8_t *dst, uint8_t *src,
		       size_t len)
{
	uint32_t j, rem;
	size_t i;

	uint16_t poly = SPDK_T10DIF_CRC16_POLYNOMIAL;

	rem = init_crc;

	for (i = 0; i < len; i++) {
		rem = rem ^ (src[i] << 8);
		dst[i] = src[i];
		for (j = 0; j < 8; j++) {
			rem = rem << 1;
			rem = (rem & 0x10000) ? rem ^ poly : rem;
		}
	}
	return (uint16_t)rem;
}