OpenWrt – Rev 1
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/*
* Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h> /* for unlink() */
#include <libgen.h>
#include <getopt.h> /* for getopt() */
#include <stdarg.h>
#include <errno.h>
#include <sys/stat.h>
#if (__BYTE_ORDER == __LITTLE_ENDIAN)
# define HOST_TO_LE16(x) (x)
# define HOST_TO_LE32(x) (x)
# define LE16_TO_HOST(x) (x)
# define LE32_TO_HOST(x) (x)
#else
# define HOST_TO_LE16(x) bswap_16(x)
# define HOST_TO_LE32(x) bswap_32(x)
# define LE16_TO_HOST(x) bswap_16(x)
# define LE32_TO_HOST(x) bswap_32(x)
#endif
uint32_t crc32buf(char *buf, size_t len);
/*
* Globals
*/
static char *ifname;
static char *progname;
static char *ofname;
/*
* Message macros
*/
#define ERR(fmt, ...) do { \
fflush(0); \
fprintf(stderr, "[%s] *** error: " fmt "\n", \
progname, ## __VA_ARGS__ ); \
} while (0)
#define ERRS(fmt, ...) do { \
int save = errno; \
fflush(0); \
fprintf(stderr, "[%s] *** error: " fmt ": %s\n", \
progname, ## __VA_ARGS__, strerror(save)); \
} while (0)
void usage(int status)
{
FILE *stream = (status != EXIT_SUCCESS) ? stderr : stdout;
struct board_info *board;
fprintf(stream, "Usage: %s [OPTIONS...]\n", progname);
fprintf(stream,
"\n"
"Options:\n"
" -i <file> read input from the file <file>\n"
" -o <file> write output to the file <file>\n"
" -h show this screen\n"
);
exit(status);
}
int main(int argc, char *argv[])
{
int res = EXIT_FAILURE;
int buflen;
int err;
struct stat st;
char *buf;
uint32_t *hdr;
uint32_t crc;
FILE *outfile, *infile;
progname = basename(argv[0]);
while ( 1 ) {
int c;
c = getopt(argc, argv, "i:o:h");
if (c == -1)
break;
switch (c) {
case 'i':
ifname = optarg;
break;
case 'o':
ofname = optarg;
break;
case 'h':
usage(EXIT_SUCCESS);
break;
default:
usage(EXIT_FAILURE);
break;
}
}
if (ifname == NULL) {
ERR("no input file specified");
goto err;
}
if (ofname == NULL) {
ERR("no output file specified");
goto err;
}
err = stat(ifname, &st);
if (err){
ERRS("stat failed on %s", ifname);
goto err;
}
buflen = st.st_size;
buf = malloc(buflen);
if (!buf) {
ERR("no memory for buffer\n");
goto err;
}
infile = fopen(ifname, "r");
if (infile == NULL) {
ERRS("could not open \"%s\" for reading", ifname);
goto err_free;
}
errno = 0;
fread(buf, buflen, 1, infile);
if (errno != 0) {
ERRS("unable to read from file %s", ifname);
goto err_close_in;
}
crc = crc32buf(buf, buflen);
hdr = (uint32_t *)buf;
*hdr = HOST_TO_LE32(crc);
outfile = fopen(ofname, "w");
if (outfile == NULL) {
ERRS("could not open \"%s\" for writing", ofname);
goto err_close_in;
}
errno = 0;
fwrite(buf, buflen, 1, outfile);
if (errno) {
ERRS("unable to write to file %s", ofname);
goto err_close_out;
}
res = EXIT_SUCCESS;
out_flush:
fflush(outfile);
err_close_out:
fclose(outfile);
if (res != EXIT_SUCCESS) {
unlink(ofname);
}
err_close_in:
fclose(infile);
err_free:
free(buf);
err:
return res;
}
/**********************************************************************/
/* The following was grabbed and tweaked from the old snippets collection
* of public domain C code. */
/**********************************************************************\
|* Demonstration program to compute the 32-bit CRC used as the frame *|
|* check sequence in ADCCP (ANSI X3.66, also known as FIPS PUB 71 *|
|* and FED-STD-1003, the U.S. versions of CCITT's X.25 link-level *|
|* protocol). The 32-bit FCS was added via the Federal Register, *|
|* 1 June 1982, p.23798. I presume but don't know for certain that *|
|* this polynomial is or will be included in CCITT V.41, which *|
|* defines the 16-bit CRC (often called CRC-CCITT) polynomial. FIPS *|
|* PUB 78 says that the 32-bit FCS reduces otherwise undetected *|
|* errors by a factor of 10^-5 over 16-bit FCS. *|
\**********************************************************************/
/* Copyright (C) 1986 Gary S. Brown. You may use this program, or
code or tables extracted from it, as desired without restriction.*/
/* First, the polynomial itself and its table of feedback terms. The */
/* polynomial is */
/* X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0 */
/* Note that we take it "backwards" and put the highest-order term in */
/* the lowest-order bit. The X^32 term is "implied"; the LSB is the */
/* X^31 term, etc. The X^0 term (usually shown as "+1") results in */
/* the MSB being 1. */
/* Note that the usual hardware shift register implementation, which */
/* is what we're using (we're merely optimizing it by doing eight-bit */
/* chunks at a time) shifts bits into the lowest-order term. In our */
/* implementation, that means shifting towards the right. Why do we */
/* do it this way? Because the calculated CRC must be transmitted in */
/* order from highest-order term to lowest-order term. UARTs transmit */
/* characters in order from LSB to MSB. By storing the CRC this way, */
/* we hand it to the UART in the order low-byte to high-byte; the UART */
/* sends each low-bit to hight-bit; and the result is transmission bit */
/* by bit from highest- to lowest-order term without requiring any bit */
/* shuffling on our part. Reception works similarly. */
/* The feedback terms table consists of 256, 32-bit entries. Notes: */
/* */
/* 1. The table can be generated at runtime if desired; code to do so */
/* is shown later. It might not be obvious, but the feedback */
/* terms simply represent the results of eight shift/xor opera- */
/* tions for all combinations of data and CRC register values. */
/* */
/* 2. The CRC accumulation logic is the same for all CRC polynomials, */
/* be they sixteen or thirty-two bits wide. You simply choose the */
/* appropriate table. Alternatively, because the table can be */
/* generated at runtime, you can start by generating the table for */
/* the polynomial in question and use exactly the same "updcrc", */
/* if your application needn't simultaneously handle two CRC */
/* polynomials. (Note, however, that XMODEM is strange.) */
/* */
/* 3. For 16-bit CRCs, the table entries need be only 16 bits wide; */
/* of course, 32-bit entries work OK if the high 16 bits are zero. */
/* */
/* 4. The values must be right-shifted by eight bits by the "updcrc" */
/* logic; the shift must be unsigned (bring in zeroes). On some */
/* hardware you could probably optimize the shift in assembler by */
/* using byte-swap instructions. */
static const uint32_t crc_32_tab[] = { /* CRC polynomial 0xedb88320 */
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};
#define UPDC32(octet,crc) (crc_32_tab[((crc) ^ (octet)) & 0xff] ^ ((crc) >> 8))
uint32_t crc32buf(char *buf, size_t len)
{
uint32_t crc;
crc = 0xFFFFFFFF;
for ( ; len; --len, ++buf)
{
crc = UPDC32(*buf, crc);
}
return crc ^ 0xFFFFFFFF;
}