/* bbc_crc.c: controleer/maak 16 bit crc van bestanden
   Copyright (C) W.H.Scholten 1996
   Deel van bbcim.
   Laatste verandering 30-6-96

   Bereken de CRC van een bestand (zie BBC user guide p.399)
*/

unsigned int fcrc(char *bestand) {
  unsigned long length=0;
  unsigned char byte;
  FILE *fp;

  unsigned int crc=0;
  int k;


  length=0; crc=0;

  fp=fopen(bestand,"rb");

  if (fp==NULL) {
#ifdef NL
    printf("Bestand %s kan niet geopend worden\n", bestand);
#else
    printf("File %s couldn't be opened\n", bestand);
#endif

    return crc;
  }

  while (1) {
    if (!fread(&byte,1,1,fp)) break;
   /* if (feof(fp)) break; */
    length++;
    crc ^=(byte << 8);
    for(k=0; k<8; k++) {
      if (crc & 32768) crc=(((crc ^ 0x0810) & 32767) << 1)+1;
      else crc <<= 1;
    }
  }
  fclose(fp);

  return crc;
}







/* CRC controle voor archief formaat */

void icrc(int argc, char *argv[], int options) {
  FILE *fparchive, *fpinfo;
  char infofile[100];
  int  archivefile,l, found, len_s, i;
  char bbc_naam[12];

  char read_line[100];
  unsigned int crc;



/* NIET GEBRUIKT: (CRC ZONDER LIJST BESTANDEN NIET GEIMPLEMENTEERD)
 if ((argc-options)<3){
     #ifdef NL
     printf("Naam van het te controleren archief bestand?");
     #else
     printf("Name of the archive file to be checked?");
     #endif
     scanf("%50s", archivefile);
     } else strcpy(archivefile, argv[2+options]);
*/


  if ((argc-options)<2) {
     #ifdef NL
    printf("Geen lijst van archief bestanden meegegeven\n");
     #else
    printf("No archive file list given\n");
     #endif
    exit(1);
  }



  for(archivefile=2; archivefile<argc; archivefile++) {


    /* .inf bestanden overslaan: */
    l=strlen(argv[archivefile]);
    if (l>4)
      if (!strncmp(argv[archivefile]+l-4,".inf",4)) continue;

    strcpy(infofile,argv[archivefile]);
    strcat(infofile,".inf");



    /* BESTAAT HET INFO BESTAND? */
    fpinfo=fopen(infofile, "r");
    if (fpinfo==NULL) {
          #ifdef NL
      printf("Info bestand %s kan niet geopend worden, sla over\n", infofile);
          #else
      printf("Info file %s cannot be opened, skipping file\n", infofile);
          #endif
      continue;
    }


    /* BESTAAT HET ARCHIEF BESTAND? */
    fparchive=fopen(argv[archivefile], "rb");
    if (fparchive==NULL) {
          #ifdef NL
      printf("Archief bestand %s kan niet geopend worden\n", argv[archivefile]);
          #else
      printf("Archive file %s cannot be opened\n", argv[archivefile]);
          #endif
      continue;
    }
    fclose(fparchive);


    /* UIT HET inf BESTAND DE BESTANDSNAAM HALEN. */
    fscanf(fpinfo,"%9s", bbc_naam);
    if (bbc_naam[1]!='.') strcpy(bbc_naam, argv[archivefile]);


    /* CRC zoeken */
    fseek(fpinfo,0L,0);
    fgets(read_line, 99, fpinfo);

    found=0;
    len_s=strlen(read_line);
    printf("bestand %-9s (%-9s) CRC ", argv[archivefile],bbc_naam);
    for (i=0; i<len_s-4; i++) {
      if (!strncmp(read_line+i,"CRC=",4)) {
	found=1;
	fseek(fpinfo, i+4L,0); fscanf(fpinfo, "%x", &crc);
	if (crc!=fcrc(argv[archivefile])) {
#ifdef NL
	  printf("fout, gevonden: %4X", crc);
#else
	  printf("wrong, found: %4X", crc);
#endif
	  crc=fcrc(argv[archivefile]);

#ifdef NL
	  printf(", berekend: %4X\n", crc);
#else
	  printf(", calculated: %4X\n", crc);
#endif
	}
	else printf("in orde\n");
	break;
      }
    }
    if (!found) printf("ontbreekt\n");

    fclose(fpinfo);
  } /*FOR */
}






/* Controleer CRC's in __CATALOG__ ($.ELITE 00E00 FF8023 ... CRC=xxxx) */

void xcrc(int argc, char *argv[], int options) {
  FILE *fpcat;
  unsigned int crc;
  int found, len_s, i;

  char bbc_file[15], read_line[100];


  fpcat=fopen("__CATALOG__", "r");
  if (fpcat==NULL) {
#ifdef NL
    printf("__CATALOG__ kon niet geopend worden\n");
#else
    printf("__CATALOG__ couldn't be opened\n");
#endif
    exit (1);
  }

  while (1) {
    if (fgets(read_line, 99, fpcat)==NULL) break;
    if (read_line[1]=='.') {
      strncpy(bbc_file, read_line, 9); bbc_file[9]=0;
      /* SPATIES AAN EINDE WEGHALEN */
      for (i=8;i>0;i--) {
	if (bbc_file[i]!=' ') break;
	bbc_file[i]=0;
      }

      found=0;
      len_s=strlen(read_line);
#ifdef NL
      printf("bestand %-9s CRC ", bbc_file);
      for (i=0; i<len_s-4; i++) {
	if (!strncmp(read_line+i,"CRC=",4)) {
	  found=1;
	  sscanf(read_line+i+4L, "%x", &crc);
	  if (crc!=fcrc(bbc_file)) {
	    printf("fout, gevonden: %4X", crc);
	    crc=fcrc(bbc_file);
	    printf(", berekend: %4X\n", crc);
	  }
	  else printf("in orde\n");
	  break;
	}
      } if (!found) printf("ontbreekt\n");
    }
#else
      printf("file %-9s CRC ", bbc_file);
      for (i=0; i<len_s-4; i++) {
	if (!strncmp(read_line+i,"CRC=",4)) {
	  found=1;
	  sscanf(read_line+i+4L, "%x", &crc);
	  if (crc!=fcrc(bbc_file)) {
	    printf("wrong, found: %4X", crc);
	    crc=fcrc(bbc_file);
	    printf(", calculated: %4X\n", crc);
	  }
	  else printf("all right\n");
	  break;
	}
      } if (!found) printf("missing\n");
    }
#endif
  } /*while*/   
}