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zTC1/mico-os/libraries/utilities/CheckSumUtils.c

119 lines
3.2 KiB
C

/**
******************************************************************************
* @file CheckSumUtils.c
* @author William Xu
* @version V1.0.0
* @date 30-July-2015
* @brief This file contains function that aid in checksum calculations.
******************************************************************************
*
* The MIT License
* Copyright (c) 2014 MXCHIP Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is furnished
* to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
* IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
******************************************************************************
*/
#include "CheckSumUtils.h"
uint8_t UpdateCRC8(uint8_t crcIn, uint8_t byte)
{
uint8_t crc = crcIn;
uint8_t i;
crc^= byte;
for(i=0;i<8;i++)
{
if(crc&0x01)
{
crc = (crc>>1)^0x8C;
}
else
crc>>=1;
}
return crc;
}
void CRC8_Init( CRC8_Context *inContext )
{
inContext->crc = 0;
}
void CRC8_Update( CRC8_Context *inContext, const void *inSrc, size_t inLen )
{
const uint8_t * src = (const uint8_t *) inSrc;
const uint8_t * srcEnd = src + inLen;
while( src < srcEnd )
inContext->crc = UpdateCRC8(inContext->crc, *src++);
}
void CRC8_Final( CRC8_Context *inContext, uint8_t *outResult )
{
//inContext->crc = UpdateCRC8(inContext->crc, 0);
*outResult = inContext->crc&0xffu;
}
/*******************************************************************************/
uint16_t UpdateCRC16(uint16_t crcIn, uint8_t byte)
{
uint32_t crc = crcIn;
uint32_t in = byte | 0x100;
do
{
crc <<= 1;
in <<= 1;
if(in & 0x100)
++crc;
if(crc & 0x10000)
crc ^= 0x1021;
}while(!(in & 0x10000));
return crc & 0xffffu;
}
void CRC16_Init( CRC16_Context *inContext )
{
inContext->crc = 0;
}
void CRC16_Update( CRC16_Context *inContext, const void *inSrc, size_t inLen )
{
const uint8_t * src = (const uint8_t *) inSrc;
const uint8_t * srcEnd = src + inLen;
while( src < srcEnd )
inContext->crc = UpdateCRC16(inContext->crc, *src++);
}
void CRC16_Final( CRC16_Context *inContext, uint16_t *outResult )
{
inContext->crc = UpdateCRC16(inContext->crc, 0);
inContext->crc = UpdateCRC16(inContext->crc, 0);
*outResult = inContext->crc&0xffffu;
}