fileio.c

这是一个非常有价值的参考代码

    if (offset+2  > len) 
      return -1;
    for (i=0; i<2; i++) 
      buf[i] = rec[offset++];
    buf[i] = 0;
    srec->data[j] = strtoul(buf, &e, 16);
    if (e == buf || *e != 0) 
      return -1;
    cksum += srec->data[j];
  }

  /* cksum */
  if (offset + 2 > len) 
    return -1;
  for (i=0; i<2; i++) 
    buf[i] = rec[offset++];
  buf[i] = 0;
  srec->cksum = strtoul(buf, &e, 16);
  if (e == buf || *e != 0) 
    return -1;

  rc = 0xff - cksum;
  return rc;
}


int srec2b(char * infile, FILE * inf,
           unsigned char * outbuf, int bufsize)
{
  char buffer [ MAX_LINE_LEN ];
  unsigned char * buf;
  unsigned int nextaddr, baseaddr, maxaddr;
  int i;
  int lineno;
  int len;
  struct ihexrec srec;
  int rc;
  int reccount;
  unsigned char datarec;

  char * msg = 0;

  lineno   = 0;
  buf      = outbuf;
  baseaddr = 0;
  maxaddr  = 0;
  reccount = 0;

  while (fgets((char *)buffer,MAX_LINE_LEN,inf)!=NULL) {
    lineno++;
    len = strlen(buffer);
    if (buffer[len-1] == '\n') 
      buffer[--len] = 0;
    if (buffer[0] != 0x53)
      continue;
    rc = srec_readrec(&srec, buffer);

    if (rc < 0) {
      fprintf(stderr, "%s: ERROR: invalid record at line %d of \"%s\"\n",
              progname, lineno, infile);
      return -1;
    }
    else if (rc != srec.cksum) {
      fprintf(stderr, "%s: ERROR: checksum mismatch at line %d of \"%s\"\n",
              progname, lineno, infile);
      fprintf(stderr, "%s: checksum=0x%02x, computed checksum=0x%02x\n",
              progname, srec.cksum, rc);
      return -1;
    }

    datarec=0;	
    switch (srec.rectyp) {
      case 0x30: /* S0 - header record*/
        /* skip */
        break;

      case 0x31: /* S1 - 16 bit address data record */
        datarec=1;
        msg="%s: ERROR: address 0x%04x out of range at line %d of %s\n";    
        break;

      case 0x32: /* S2 - 24 bit address data record */
        datarec=1;
        msg="%s: ERROR: address 0x%06x out of range at line %d of %s\n";
        break;

      case 0x33: /* S3 - 32 bit address data record */
        datarec=1;
        msg="%s: ERROR: address 0x%08x out of range at line %d of %s\n";
        break;

      case 0x34: /* S4 - symbol record (LSI extension) */
        fprintf(stderr, 
                "%s: ERROR: not supported record at line %d of %s\n",
                progname, lineno, infile);
        return -1;

      case 0x35: /* S5 - count of S1,S2 and S3 records previously tx'd */
        if (srec.loadofs != reccount){
          fprintf(stderr, 
                  "%s: ERROR: count of transmitted data records mismatch "
                  "at line %d of \"%s\"\n",
                  progname, lineno, infile);
          fprintf(stderr, "%s: transmitted data records= %d, expected "
                  "value= %d\n",
                  progname, reccount, srec.loadofs);
          return -1;
        }
        break;

      case 0x37: /* S7 Record - end record for 32 bit address data */
      case 0x38: /* S8 Record - end record for 24 bit address data */
      case 0x39: /* S9 Record - end record for 16 bit address data */
        return maxaddr;

      default:
        fprintf(stderr, 
                "%s: ERROR: don't know how to deal with rectype S%d " 
                "at line %d of %s\n",
                progname, srec.rectyp, lineno, infile);
        return -1;
    }

    if (datarec == 1) {
      nextaddr = srec.loadofs + baseaddr;
      if (nextaddr + srec.reclen > bufsize) {
        fprintf(stderr, msg, progname, nextaddr+srec.reclen, lineno, infile);
        return -1;
      }
      for (i=0; i<srec.reclen; i++) 
        buf[nextaddr+i] = srec.data[i];
      if (nextaddr+srec.reclen > maxaddr)
        maxaddr = nextaddr+srec.reclen;
      reccount++;	
    }

  } 

  fprintf(stderr, 
          "%s: WARNING: no end of file record found for Motorola S-Records "
          "file \"%s\"\n",
          progname, infile);

  return maxaddr;
}


int fileio_rbin(struct fioparms * fio,
                  char * filename, FILE * f, unsigned char * buf, int size)
{
  int rc;

  switch (fio->op) {
    case FIO_READ:
      rc = fread(buf, 1, size, f);
      break;
    case FIO_WRITE:
      rc = fwrite(buf, 1, size, f);
      break;
    default:
      fprintf(stderr, "%s: fileio: invalid operation=%d\n",
              progname, fio->op);
      return -1;
  }

  if (rc < 0 || (fio->op == FIO_WRITE && rc < size)) {
    fprintf(stderr, 
            "%s: %s error %s %s: %s; %s %d of the expected %d bytes\n", 
            progname, fio->iodesc, fio->dir, filename, strerror(errno),
            fio->rw, rc, size);
    return -1;
  }

  return rc;
}


int fileio_imm(struct fioparms * fio,
               char * filename, FILE * f, unsigned char * buf, int size)
{
  int rc = 0;
  char * e, * p;
  unsigned long b;
  int loc;

  switch (fio->op) {
    case FIO_READ:
      loc = 0;
      p = strtok(filename, " ,");
      while (p != NULL && loc < size) {
        b = strtoul(p, &e, 0);
        if (*e != 0) {
          fprintf(stderr,
                  "%s: invalid byte value (%s) specified for immediate mode\n",
                  progname, p);
          return -1;
        }
        buf[loc++] = b;
        p = strtok(NULL, " ,");
        rc = loc;
      }
      break;
    default:
      fprintf(stderr, "%s: fileio: invalid operation=%d\n",
              progname, fio->op);
      return -1;
  }

  if (rc < 0 || (fio->op == FIO_WRITE && rc < size)) {
    fprintf(stderr, 
            "%s: %s error %s %s: %s; %s %d of the expected %d bytes\n", 
            progname, fio->iodesc, fio->dir, filename, strerror(errno),
            fio->rw, rc, size);
    return -1;
  }

  return rc;
}


int fileio_ihex(struct fioparms * fio, 
                  char * filename, FILE * f, unsigned char * buf, int size)
{
  int rc;

  switch (fio->op) {
    case FIO_WRITE:
      rc = b2ihex(buf, size, 32, 0, filename, f);
      if (rc < 0) {
        return -1;
      }
      break;

    case FIO_READ:
      rc = ihex2b(filename, f, buf, size);
      if (rc < 0)
        return -1;
      break;

    default:
      fprintf(stderr, "%s: invalid Intex Hex file I/O operation=%d\n",
              progname, fio->op);
      return -1;
      break;
  }

  return rc;
}


int fileio_srec(struct fioparms * fio,
                  char * filename, FILE * f, unsigned char * buf, int size)
{
  int rc;

  switch (fio->op) {
    case FIO_WRITE:
      rc = b2srec(buf, size, 32, 0, filename, f);
      if (rc < 0) {
        return -1;
      }
      break;

    case FIO_READ:
      rc = srec2b(filename, f, buf, size);
      if (rc < 0)
        return -1;
      break;

    default:
      fprintf(stderr, "%s: ERROR: invalid Motorola S-Records file I/O "
              "operation=%d\n",
              progname, fio->op);
      return -1;
      break;
  }

  return rc;
}


int fileio_setparms(int op, struct fioparms * fp)
{
  fp->op = op;

  switch (op) {
    case FIO_READ:
      fp->mode   = "r";
      fp->iodesc = "input";
      fp->dir    = "from";
      fp->rw     = "read";
      break;

    case FIO_WRITE:
      fp->mode   = "w";
      fp->iodesc = "output";
      fp->dir    = "to";
      fp->rw     = "wrote";
      break;

    default:
      fprintf(stderr, "%s: invalid I/O operation %d\n",
              progname, op);
      return -1;
      break;
  }

  return 0;
}



int fmt_autodetect(char * fname)
{
  FILE * f;
  unsigned char buf[MAX_LINE_LEN];
  int i;
  int len;
  int found;

  f = fopen(fname, "r");
  if (f == NULL) {
    fprintf(stderr, "%s: error opening %s: %s\n",
            progname, fname, strerror(errno));
    return -1;
  }

  while (fgets((char *)buf, MAX_LINE_LEN, f)!=NULL) {
    buf[MAX_LINE_LEN-1] = 0;
    len = strlen((char *)buf);
    if (buf[len-1] == '\n')
      buf[--len] = 0;

    /* check for binary data */
    found = 0;
    for (i=0; i<len; i++) {
      if (buf[i] > 127) {
        found = 1;
        break;
      }
    }
    if (found)
      return FMT_RBIN;

    /* check for lines that look like intel hex */
    if ((buf[0] == ':') && (len >= 11)) {
      found = 1;
      for (i=1; i<len; i++) {
        if (!isxdigit(buf[1])) {
          found = 0;
          break;
        }
      }
      if (found)
        return FMT_IHEX;
    }

    /* check for lines that look like motorola s-record */
    if ((buf[0] == 'S') && (len >= 10) && isdigit(buf[1])) {
      found = 1;
      for (i=1; i<len; i++) {
        if (!isxdigit(buf[1])) {
          found = 0;
          break;
        }
      }
      if (found)
        return FMT_SREC;
    }
  }

  return -1;
}



int fileio(int op, char * filename, FILEFMT format, 
             struct avrpart * p, char * memtype, int size)
{
  int rc;
  FILE * f;
  char * fname;
  unsigned char * buf;
  struct fioparms fio;
  AVRMEM * mem;
  int using_stdio;

  mem = avr_locate_mem(p, memtype);
  if (mem == NULL) {
    fprintf(stderr, 
            "fileio(): memory type \"%s\" not configured for device \"%s\"\n",
            memtype, p->desc);
    return -1;
  }

  rc = fileio_setparms(op, &fio);
  if (rc < 0)
    return -1;

  #if defined(WIN32NATIVE)
  /* Open Raw Binary format in binary mode on Windows.*/
  if(format == FMT_RBIN)
  {
      if(fio.op == FIO_READ)
      {
          fio.mode = "rb";
      }
      if(fio.op == FIO_WRITE)
      {
          fio.mode = "wb";
      }
  }
  #endif

  /* point at the requested memory buffer */
  buf = mem->buf;
  if (fio.op == FIO_READ)
    size = mem->size;

  if (fio.op == FIO_READ) {
    /* 0xff fill unspecified memory */
    memset(buf, 0xff, size);
  }

  using_stdio = 0;

  if (strcmp(filename, "-")==0) {
    if (fio.op == FIO_READ) {
      fname = "<stdin>";
      f = stdin;
    }
    else {
      fname = "<stdout>";
      f = stdout;
    }
    using_stdio = 1;
  }
  else {
    fname = filename;
    f = NULL;
  }

  if (format == FMT_AUTO) {
    if (using_stdio) {
      fprintf(stderr, 
              "%s: can't auto detect file format when using stdin/out.\n"
              "     Please specify a file format using the -f option and try again.\n", 
              progname);
      exit(1);
    }

    format = fmt_autodetect(fname);
    if (format < 0) {
      fprintf(stderr, 
              "%s: can't determine file format for %s, specify explicitly\n",
              progname, fname);
      return -1;
    }

    if (quell_progress < 2) {
      fprintf(stderr, "%s: %s file %s auto detected as %s\n", 
              progname, fio.iodesc, fname, fmtstr(format));
    }
  }

  if (format != FMT_IMM) {
    if (!using_stdio) {
      f = fopen(fname, fio.mode);
      if (f == NULL) {
        fprintf(stderr, "%s: can't open %s file %s: %s\n",
                progname, fio.iodesc, fname, strerror(errno));
        return -1;
      }
    }
  }

  switch (format) {
    case FMT_IHEX:
      rc = fileio_ihex(&fio, fname, f, buf, size);
      break;

    case FMT_SREC:
      rc = fileio_srec(&fio, fname, f, buf, size);
      break;

    case FMT_RBIN:
      rc = fileio_rbin(&fio, fname, f, buf, size);
      break;

    case FMT_IMM:
      rc = fileio_imm(&fio, fname, f, buf, size);
      break;

    default:
      fprintf(stderr, "%s: invalid %s file format: %d\n",
              progname, fio.iodesc, format);
      return -1;
  }

  if (rc > 0) {
    if ((op == FIO_READ) && (strcasecmp(mem->desc, "flash") == 0)) {
      /*
       * if we are reading flash, just mark the size as being the
       * highest non-0xff byte
       */
      rc = avr_mem_hiaddr(mem);
    }
  }

  return rc;
}