xref: /illumos-gate/usr/src/cmd/hostname/hostname.c (revision 1a2d662a91cee3bf82f41cd47c7ae6f3825d9db2)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * University Copyright- Copyright (c) 1982, 1986, 1988
24  * The Regents of the University of California
25  * All Rights Reserved
26  *
27  * University Acknowledgment- Portions of this document are derived from
28  * software developed by the University of California, Berkeley, and its
29  * contributors.
30  */
31 
32 /*
33  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
34  * Use is subject to license terms.
35  */
36 
37 /* Portions Copyright 2007 Jeremy Teo */
38 /* Portions Copyright 2006 Stephen P. Potter */
39 
40 #include <unistd.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <locale.h>
44 #include <libgen.h>
45 #include <stdlib.h>
46 #include <errno.h>
47 #include <netdb.h>
48 
49 #ifndef	TEXT_DOMAIN		/* should be defined by cc -D */
50 #define	TEXT_DOMAIN "SYS_TEST"	/* use this only if it wasn't */
51 #endif
52 
53 static char *progname;
54 
55 static void
56 usage(void)
57 {
58 	(void) fprintf(stderr, gettext("usage: %s [-s] [system_name]\n"),
59 	    basename(progname));
60 	exit(1);
61 }
62 
63 int
64 main(int argc, char *argv[])
65 {
66 	char	*nodename = NULL;
67 	char    c_hostname[MAXHOSTNAMELEN];
68 	int	optlet;
69 	int	sflag = 0;
70 	char	*optstring = "s";
71 
72 	(void) setlocale(LC_ALL, "");
73 	(void) textdomain(TEXT_DOMAIN);
74 
75 	progname = argv[0];
76 
77 	opterr = 0;
78 	while ((optlet = getopt(argc, argv, optstring)) != -1) {
79 		switch (optlet) {
80 		case 's':
81 			sflag = 1;
82 			break;
83 		case '?':
84 			usage();
85 			break;
86 		}
87 	}
88 
89 	/*
90 	 * if called with no arguments, just print out the hostname/nodename
91 	 */
92 	if (argc <= optind) {
93 		if (gethostname(c_hostname, sizeof (c_hostname)) < 0) {
94 			(void) fprintf(stderr,
95 			    gettext("%s: unable to obtain hostname\n"),
96 			    basename(progname));
97 			exit(1);
98 		} else {
99 			if (sflag)
100 				c_hostname[strcspn(c_hostname, ".")] = '\0';
101 			(void) fprintf(stdout, "%s\n", c_hostname);
102 		}
103 	} else {
104 		/*
105 		 * if called with an argument,
106 		 * we have to try to set the new hostname/nodename
107 		 */
108 		if (argc > optind + 1)
109 			usage();	/* too many arguments */
110 
111 		nodename = argv[optind];
112 		if (sethostname(nodename, strlen(nodename)) < 0) {
113 			int err = errno;
114 			(void) fprintf(stderr,
115 			    gettext("%s: error in setting name: %s\n"),
116 			    basename(progname), strerror(err));
117 			exit(1);
118 		}
119 	}
120 	return (0);
121 }
122