com32/libupload/upload_srec.c

   1 /*
   2  * S-records dump routine -- dumps S-records on the console
   3  */
   4
   5 #include <string.h>
   6 #include <stdio.h>
   7 #include <inttypes.h>
   8 #include <minmax.h>
   9 #include "upload_backend.h"
  10
  11 /* Write a single S-record */
  12 static int write_srecord(unsigned int len,  unsigned int alen,
  13                          uint32_t addr, uint8_t type, const void *data)
  14 {
  15     char buf[2+2+8+255*2+2+2];
  16     char *p = buf;
  17     uint8_t csum;
  18     const uint8_t *dptr = data;
  19     unsigned int i;
  20
  21     switch (alen) {
  22     case 2:
  23         addr &= 0xffff;
  24         break;
  25     case 3:
  26         addr &= 0xffffff;
  27         break;
  28     case 4:
  29         break;
  30     }
  31
  32     csum = (len+alen+1) + addr + (addr >> 8) + (addr >> 16) + (addr >> 24);
  33     for (i = 0; i < len; i++)
  34         csum += dptr[i];
  35     csum = 0xff-csum;
  36
  37     p += sprintf(p, "S%c%02X%0*X", type, len+alen+1, alen*2, addr);
  38     for (i = 0; i < len; i++)
  39         p += sprintf(p, "%02X", dptr[i]);
  40     p += sprintf(p, "%02X\n", csum);
  41
  42     fputs(buf, stdout);
  43     return 0;
  44 }
  45
  46 static int upload_srec_write(struct upload_backend *be)
  47 {
  48     char name[33];
  49     const char *buf;
  50     size_t len, chunk, offset, hdrlen;
  51
  52     buf = be->outbuf;
  53     len = be->zbytes;
  54
  55     putchar('\n');
  56
  57     hdrlen = snprintf(name, sizeof name, "%.32s",
  58                       be->argv[0] ? be->argv[0] : "");
  59
  60     /* Write head record */
  61     write_srecord(hdrlen, 2, 0, '0', name);
  62
  63     /* Write data records */
  64     offset = 0;
  65     while (len) {
  66         chunk = min(len, (size_t)32);
  67
  68         write_srecord(chunk, 4, offset, '3', buf);
  69         buf += chunk;
  70         len -= chunk;
  71         offset += chunk;
  72     }
  73
  74     /* Write termination record */
  75     write_srecord(0, 4, 0, '7', NULL);
  76
  77     return 0;
  78 }
  79
  80 struct upload_backend upload_srec = {
  81     .name       = "srec",
  82     .helpmsg    = "[filename]",
  83     .minargs    = 0,
  84     .write      = upload_srec_write,
  85 };