/* Append a boot table section to the end of a boot table 
 * usage: bfaddsect infile addr byte1 [bytes2 [byte3 [...]]]
 * The output is to stdout
 * 
 * All values are taken to be btye values */


#include <stdio.h>
#include <malloc.h>



int asciiByte (unsigned char c)
{
  if ((c >= '0') && (c <= '9'))
    return (1);

  if ((c >= 'A') && (c <= 'F'))
    return (1);

  return (0);
}

int toNum (unsigned char c)
{
  if ((c >= '0') && (c <= '9'))
    return (c - '0');

  return (c - 'A' + 10);

}


/* Copy a line from s to stdout */
void  lineCpy (FILE *s)
{
  char iline[132];

  fgets (iline, 131, s);
  fputs (iline, stdout);

}

/* Read a .b file. */
int readBFile (FILE *s, unsigned char *data, unsigned maxSize)
{
  unsigned char x, y;
  int byteCount = 0;

  for (;;) {

    /* read the 1st ascii char */
    do  {
      x = fgetc (s);
      if (x == (unsigned char)EOF)
        return (byteCount);

    } while (!asciiByte(x));

    /* Read the next ascii char */
    y = fgetc (s);
    if (y == (unsigned char)EOF)
      return (byteCount);
    if (asciiByte(y))
      data[byteCount++] = (toNum(x) << 4) | toNum (y);

    if (byteCount >= maxSize)  {
      fprintf (stderr, "Max input array size exceeded\n");
      return (-1);
    }

  }

}

unsigned dwordConvert (unsigned char *data)
{
  unsigned value;
  unsigned char c[4];
  int i;

  c[0] = c[1] = c[2] = c[3] = 0;
  
  for (i = 0; i < 4; i++)  {
    c[i] = data[i];
  }

  value = c[3] | (c[2] << 8) | (c[1] << 16) | (c[0] << 24);

  return (value);

}

#define SIZE    0x100000  /* max number of bytes in the array */
#define MAX_BYTES   64    /* max size of the boot table       */

int main (int argc, char *argv[])
{
  FILE *strin;
  unsigned char *dataSet;
  unsigned int addr;
  unsigned int secsize;
  unsigned char newchars[MAX_BYTES];
  int i;
  int nbytes;
  int asize;
  int p;


  /* get the args */
  if (argc < 4)  {
    fprintf (stderr, "usage: %s infile hex_addr byte1 [byte2 [byte3 [ ...byte64]]]\n", argv[0]);
    return (-1);
  }

  /* input file */
  strin = fopen (argv[1], "r");
  if (strin == NULL)  {
    fprintf (stderr, "%s: Could not open file %s\n", argv[0], argv[1]);
    return (-1);
  }

  /* Address */
  sscanf (argv[2], "%x", &addr);

  /* Number of bytes */
  nbytes = argc - 3;
  for (i = 0; i < nbytes; i++)
    sscanf (argv[i+3], "%x", &newchars[i]);


  /* Allocate memory for the data set */
  dataSet = malloc (SIZE * sizeof (unsigned char));
  if (dataSet == NULL)  {
    fprintf (stderr, "%s: malloc failure\n", argv[0]);
    return (-1);
  }

  /* Copy the first two lines of the input file to stdout */
  lineCpy (strin);
  lineCpy (strin);

  /* Read the data into the byte stream */
  asize = readBFile (strin, dataSet, SIZE);
  fclose (strin);
  
  /* Parse the input file. Prepend the new section at the end */

  /* Just skip the entry address */
  p = 4;

  do  {
    secsize = dwordConvert (&dataSet[p]);
    secsize = (secsize + 3) & 0xfffffffc;  /* segment pad */
    p = p + secsize + 8;  /* 4 bytes length, 4 bytes address */
  } while (secsize);

  /* back up to the zero section size */
  p = p - 8; 

  /* p now points to the 0 length entry. Put the new data here */
  /* The section size */
  dataSet[p++] = (nbytes >> 24) & 0xff;
  dataSet[p++] = (nbytes >> 16) & 0xff;
  dataSet[p++] = (nbytes >>  8) & 0xff;
  dataSet[p++] = (nbytes >>  0) & 0xff;

  /* Put the section address */
  dataSet[p++] = (addr >> 24) & 0xff;
  dataSet[p++] = (addr >> 16) & 0xff;
  dataSet[p++] = (addr >>  8) & 0xff;
  dataSet[p++] = (addr >>  0) & 0xff;

  /* Put the data */
  for (i = 0; i < nbytes; i++)
    dataSet[p++] = newchars[i];

  while (p % 4)
    dataSet[p++] = 0;

  /* Add the 0 length section */
  for (i = 0; i < 4; i++)
    dataSet[p++] = 0;


  /* Write out the data */
  for (i = 0; i < p; i++)  {
    fprintf (stdout, "%02X", dataSet[i]);

    if ( ((i+1) % 24) )
      fprintf (stdout, " ");
    else
      fprintf (stdout, "\n");

  }

  /* Write the trailing character */
  fprintf (stdout, "\n%c",3);

  free (dataSet);

  return (0);

}