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