/*
   The following routines can be used to interpret the crc_table.
   First use init_crc; then add_crc for each character, from
   first to last; and finally, as report_crc to yield the
   result. It is probably much more convenient to code these
   routines inline; this file serves primarily as documentation.
*/

#include <stdio.h>
#include "crc_tab.h"

static unsigned short crc;

void init_crc() { crc = 0; }

void add_crc(c)
unsigned char c;
{
  crc = crc_table[(crc & 0x00ff) ^ c] ^ (crc >> 8);
}

unsigned short report_crc() { return crc; }

void crcfile(name)
char *name;
{
  FILE *f; int c; unsigned short ck;

  printf("crc %s ", name);
  f = fopen(name, "rb");
  if (!f) {
	printf("cannot find %s\n", name);
	return;
  }

  init_crc();

  while((c = getc(f)) >= 0) {
	add_crc(c);
  }

  ck =  report_crc();

#ifdef AMIGA
  printf("0x%x %d\n", ck, ck);
#else
  printf("%#.4x %d\n", ck, ck);
#endif

  fclose(f);

  return;
}

void main(argc, argv)
int argc; char *argv[];
{
  int i; char **c;

  if (argc < 2){
	printf("crc filenames\n");
	exit(1);
  }

  c = &(argv[1]); i=argc;

  while(--i) crcfile(*c++);

  exit(0);
}