rockbox/firmware/include/checksum.h

42 lines
1.4 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2020 James Buren
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <stdint.h>
#include <stdbool.h>
#ifndef _CHECKSUM_H
#define _CHECKSUM_H
/* rockbox firmware checksum algorithm */
static inline uint32_t calc_checksum(uint32_t sum, const uint8_t* buf, size_t len)
{
for (size_t i = 0; i < len; i++)
sum += buf[i];
return sum;
}
/* similar to above but only used for verification */
static inline bool verify_checksum(uint32_t cs, const uint8_t* buf, size_t len)
{
return (calc_checksum(MODEL_NUMBER, buf, len) == cs);
}
#endif