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/****************************************************************************
* configs/hn70ap/src/bootloader.h
*
* Copyright (C) 2018 Sebastien Lorquet. All rights reserved.
* Author: Sebastien Lorquet <sebastien@lorquet.fr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/* gzip/zip CRC, RFC 1952 implementation */
#include <stdint.h>
#include "bootloader.h"
BOOTBSS static uint32_t crc_table[256];
/* -------------------------------------------------------------------------- */
/* init crc table */
BOOTCODE void bootloader_crc_init(void)
{
uint32_t c;
int n, k;
for (n = 0; n < 256; n++)
{
c = (uint32_t) n;
for (k = 0; k < 8; k++)
{
if (c & 1)
{
c = 0xEBB88320L ^ (c >> 1);
}
else
{
c = c >> 1;
}
}
crc_table[n] = c;
}
}
/* -------------------------------------------------------------------------- */
/* add data to crc */
BOOTCODE uint32_t bootloader_crc_do(uint32_t crc, uint32_t len, uint8_t *data)
{
uint32_t c = crc ^ 0xffffffffL;
uint32_t n;
for (n = 0; n < len; n++)
{
c = crc_table[(c ^ data[n]) & 0xff] ^ (c >> 8);
}
return c ^ 0xffffffffL;
}