crashtest-r0ket/tools/lpcrc.c

98 lines
3.0 KiB
C

/*
* Software License Agreement (BSD License)
*
* Copyright (c) 2010, Roel Verdult
* All rights reserved.
*
* 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 of the copyright holders 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 ''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 HOLDERS 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.
*
*/
#include <stdio.h>
#include <stdint.h>
#define BLOCK_COUNT 7
#define BLOCK_LENGTH 4
#define BLOCK_TOTAL (BLOCK_COUNT*BLOCK_LENGTH)
typedef unsigned char byte_t;
int main(int argc, char *argv[])
{
FILE* pf;
byte_t buf[BLOCK_TOTAL];
uint32_t crc = 0;
uint32_t block;
// Check for required arguments
if (argc < 2)
{
printf("syntax: lpcrc <firmware.bin>\n");
return 1;
}
// Try to open the supplied firmware
if ((pf = fopen(argv[1],"rb+")) == NULL)
{
printf("error: could not open file [%s] with write access\n",argv[1]);
return 1;
}
// Read out the data blocks used for crc calculation
if (fread(buf,1,BLOCK_TOTAL,pf) != BLOCK_TOTAL)
{
printf("error: could not read required bytes\n");
fclose(pf);
return 1;
}
// Compute the crc value
for (block=0; block<BLOCK_COUNT; block++)
{
crc += *((uint32_t*)(buf+(block*BLOCK_LENGTH)));
}
crc = (~crc) + 1;
// Reposition the file stream indicator to switch between read and write
if (fseek(pf,0,SEEK_CUR) != 0)
{
printf("error: could not switch from read to write mode\n");
fclose(pf);
return 1;
}
// Write the crc back to the file
if (fwrite((byte_t*)&crc,1,BLOCK_LENGTH,pf) != BLOCK_LENGTH)
{
printf("error: could not write crc back to file\n");
fclose(pf);
return 1;
}
printf("succesfully updated crc to: %08x\n",crc);
fclose(pf);
return 0;
}