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RedBoot: load.c srecord input offset fix



The "offset" variable in load_srec_image() isn't incremented
properly (assuming its purpose is to keep track of the current
byte offset in the input stream).  My version of load.c has
diverged enough that I can't generate a usable patch, so I'll
summarize the changes:

Increment at top of main while loop:

     while ((c = (*getc)()) > 0) {
+        ++offset;
         lp = line;  len = 0;
         // Start of line
         if (c != 'S') {

Double the byte-count for the address field to get the
character count since calling _hex2(func,N,&sum) consumes 2N
characters from the input stream::

         case '2':
         case '3':
             base_addr = addr = (unsigned char *)_hex2(getc, (type-'1'+2), &sum);
-            offset += (type-'1'+2);
+            offset += (type-'1'+2)*2;
             if (first_addr) {
                 if (base) {
                     addr_offset = (unsigned long)base - (unsigned long)addr;

Double the byte-count for the data field to get the character
count, and incrment by 2 instead of 1 for the checksum byte:

                 return;
             }
             count -= ((type-'1'+2)+1);
-            offset += count;
+            offset += count*2;
             while (count-- > 0) {
                 val = _hex2(getc, 1, &sum);
                 *addr++ = val;
             }
             cksum = _hex2(getc, 1, 0);
-            offset += 1;
+            offset += 2;
             sum = sum & 0xFF;
             cksum = (~cksum & 0xFF);
             if (cksum != sum) {

-- 
Grant Edwards
grante@visi.com


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