add System V and BSD historic algorithms

[unix-history] / usr / src / usr.bin / cksum / cksum.c

/*-
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* James W. Williams of the University of Maryland.
*
* %sccs.include.redist.c%
*/

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1991 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)cksum.c     5.3 (Berkeley) %G%";
#endif /* not lint */

#include <sys/cdefs.h>
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "extern.h"

main(argc, argv)
       int argc;
       char **argv;
{
       extern int optind;
       u_long len, val;
       register int ch, fd, rval;
       char *fn;
       int (*cfncn) __P((int, unsigned long *, unsigned long *));
       void (*pfncn) __P((char *, unsigned long, unsigned long));

       cfncn = crc;
       pfncn = pcrc;
       while ((ch = getopt(argc, argv, "o:")) != EOF)
               switch(ch) {
               case 'o':
                       if (*optarg == '1') {
                               cfncn = csum1;
                               pfncn = psum1;
                       } else if (*optarg == '2') {
                               cfncn = csum2;
                               pfncn = psum2;
                       } else {
                               (void)fprintf(stderr,
                                   "cksum: illegal argument to -o option\n");
                               usage();
                       }
                       break;
               case '?':
               default:
                       usage();
               }
       argc -= optind;
       argv += optind;

       fd = STDIN_FILENO;
       fn = "stdin";
       rval = 0;
       do {
               if (*argv) {
                       fn = *argv++;
                       if ((fd = open(fn, O_RDONLY, 0)) < 0) {
                               (void)fprintf(stderr,
                                   "cksum: %s: %s\n", fn, strerror(errno));
                               rval = 1;
                               continue;
                       }
               }
               if (cfncn(fd, &val, &len)) {
                       (void)fprintf(stderr,
                           "cksum: %s: %s\n", fn, strerror(errno));
                       rval = 1;
               } else
                       pfncn(fn, val, len);
               (void)close(fd);
       } while (*argv);
       exit(rval);
}

usage()
{
       (void)fprintf(stderr, "usage: cksum [-o 1 | 2] [file ...]\n");
       exit(1);
}