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/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "crc8.h"
/**
* Return CRC-8 of the data, using x^8 + x^2 + x + 1 polynomial. A table-based
* algorithm would be faster, but for only a few bytes it isn't worth the code
* size. */
uint8_t Crc8(const void *vptr, int len)
{
const uint8_t *data = vptr;
unsigned crc = 0;
int i, j;
for (j = len; j; j--, data++) {
crc ^= (*data << 8);
for(i = 8; i; i--) {
if (crc & 0x8000)
crc ^= (0x1070 << 3);
crc <<= 1;
}
}
return (uint8_t)(crc >> 8);
}
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