crc8.c

// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
//
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#include <stdint.h>

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);
}