memory hex dump

hex_dump.c

void HexDump(const char *buf, int len, int addr) {
  int i, j, k, n;
  char binstr[80];

  n = 0;
  for (i = 0; i < len; i++) {
    if (0 == (i % 16)) {
      n += sprintf(binstr+n, "%08x -", i + addr);
    }
    n += sprintf(binstr+n, " %02x", (unsigned char)buf[i]);
    if (15 == (i % 16)) {
      n += sprintf(binstr+n, "  ");
      for (j = i - 15; j <= i; j++) {
        n += sprintf(binstr+n, "%c",
            ('!' <= buf[j] && buf[j] <= '~') ? buf[j] : '.');
      }
      printf("%s\n", binstr);
      n = 0;
    }
  }

  if (0 != (i % 16)) {
    k = 16 - (i % 16);
    for (j = 0; j < k; j++) {
      n += sprintf(binstr+n, "   ");
    }
    n += sprintf(binstr+n, "  ");
    k = 16 - k;
    for (j = i - k; j < i; j++) {
      n += sprintf(binstr+n, "%c",
          ('!' <= buf[j] && buf[j] <= '~') ? buf[j] : '.');
    }
    printf("%s\n", binstr);
  }
}