bin/domainname/domainname.c

   1 /*
   2  * Copyright (c) 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1988, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)hostname.c       8.1 (Berkeley) 5/31/93
  35  * $FreeBSD: src/bin/domainname/domainname.c,v 1.12.2.1 2001/08/01 02:32:16 obrien Exp $
  36  * $DragonFly: src/bin/domainname/domainname.c,v 1.7 2005/03/01 23:12:37 liamfoy Exp $
  37  */
  38
  39 #include <sys/param.h>
  40
  41 #include <err.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46
  47 static void     usage(void);
  48
  49 int
  50 main(int argc, char **argv)
  51 {
  52         int ch;
  53         char domainname[MAXHOSTNAMELEN];
  54
  55         while ((ch = getopt(argc, argv, "")) != -1) {
  56                 switch (ch) {
  57                 default:
  58                         usage();
  59                 }
  60         }
  61         argc -= optind;
  62         argv += optind;
  63
  64         if (argc > 1)
  65                 usage();
  66
  67         if (argv[0] != NULL) {
  68                 size_t len = strlen(argv[0]);
  69                 if (len > MAXHOSTNAMELEN)
  70                         errx(1, "domain name too long");
  71
  72                 if (setdomainname(*argv, len))
  73                         err(1, "setdomainname");
  74         } else {
  75                 if (getdomainname(domainname, sizeof(domainname)))
  76                         err(1, "getdomainname");
  77                 domainname[MAXHOSTNAMELEN-1] = '\0';
  78                 printf("%s\n", domainname);
  79         }
  80         exit(0);
  81 }
  82
  83 static void
  84 usage(void)
  85 {
  86         fprintf(stderr, "usage: domainname [ypdomain]\n");
  87         exit(1);
  88 }