aboutsummaryrefslogtreecommitdiffstats
path: root/tools/firmware-utils/src/encode_crc.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/firmware-utils/src/encode_crc.c')
-rwxr-xr-xtools/firmware-utils/src/encode_crc.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/tools/firmware-utils/src/encode_crc.c b/tools/firmware-utils/src/encode_crc.c
new file mode 100755
index 0000000000..647fb92e89
--- /dev/null
+++ b/tools/firmware-utils/src/encode_crc.c
@@ -0,0 +1,151 @@
+/* **************************************************************************
+
+ This program creates a CRC checksum and encodes the file that is named
+ in the command line.
+
+ Compile with: gcc encode_crc.c -Wall -o encode_crc
+
+ Author: Michael Margraf (michael.margraf@freecom.com)
+ Copyright: Freecom Technology GmbH, Berlin, 2004
+ www.freecom.com
+
+ 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 program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ ************************************************************************* */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+// *******************************************************************
+// CCITT polynom G(x)=x^16+x^12+x^5+1
+#define POLYNOM 0x1021
+
+// CRC algorithm with MSB first
+int make_crc16(int crc, char new)
+{
+ int i;
+ crc = crc ^ (((int)new) << 8);
+
+ for(i=0; i<8; i++) { // work on 8 bits in "new"
+ crc <<= 1; // MSBs first
+ if(crc & 0x10000) crc ^= POLYNOM;
+ }
+ return crc & 0xFFFF;
+}
+
+// *******************************************************************
+// Reads the file "filename" into memory and returns pointer to the buffer.
+static char *readfile(char *filename, int *size)
+{
+ FILE *fp;
+ char *buffer;
+ struct stat info;
+
+ if (stat(filename,&info)!=0)
+ return NULL;
+
+ if ((fp=fopen(filename,"r"))==NULL)
+ return NULL;
+
+ buffer=NULL;
+ for (;;)
+ {
+ if ((buffer=(char *)malloc(info.st_size+1))==NULL)
+ break;
+
+ if (fread(buffer,1,info.st_size,fp)!=info.st_size)
+ {
+ free(buffer);
+ buffer=NULL;
+ break;
+ }
+
+ buffer[info.st_size]='\0';
+ if(size) *size = info.st_size;
+
+ break;
+ }
+
+ (void)fclose(fp);
+
+ return buffer;
+}
+
+
+// *******************************************************************
+int main(int argc, char** argv)
+{
+ if(argc < 3) {
+ printf("ERROR: Argument missing!\n\n");
+ return 1;
+ }
+
+ int count; // size of file in bytes
+ char *p, *master = readfile(argv[1], &count);
+ if(!master) {
+ printf("ERROR: File not found!\n");
+ return 1;
+ }
+
+ int crc = 0xFFFF, z;
+
+ p = master;
+ for(z=0; z<count; z++)
+ crc = make_crc16(crc, *(p++)); // calculate CRC
+ short crc16 = (short)crc;
+
+ /*
+ if(argc > 2) { // with flag for device recognition ?
+ p = argv[2];
+ for(z=strlen(p); z>0; z--) {
+ crc ^= (int)(*p);
+ *(p++) = (char)crc; // encode device flag
+ }
+ }
+ */
+
+ p = master;
+ for(z=0; z<count; z++) {
+ crc ^= (int)(*p);
+ *(p++) = (char)crc; // encode file
+ }
+
+
+ // write encoded file...
+ FILE *fp = fopen(argv[2], "w");
+ if(!fp) {
+ printf("ERROR: File not writeable!\n");
+ return 1;
+ }
+
+ if(argc > 3) { // add flag for device recognition ?
+ fwrite(argv[3], strlen(argv[3]), sizeof(char), fp);
+ }
+ else {
+ // Device is an FSG, so byte swap (IXP4xx is big endian)
+ crc16 = ((crc16 >> 8) & 0xFF) | ((crc16 << 8) & 0xFF00);
+ }
+
+ fwrite(&crc16, 1, sizeof(short), fp); // first write CRC
+
+ fwrite(master, count, sizeof(char), fp); // write content
+ fclose(fp);
+
+ free(master);
+ return 0;
+}