xref: /illumos-gate/usr/src/lib/libnsl/rpc/rpcdname.c (revision 7a6d80f1660abd4755c68cbd094d4a914681d26e)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29 /*
30  * Portions of this source code were derived from Berkeley
31  * 4.3 BSD under license from the Regents of the University of
32  * California.
33  */
34 
35 /*
36  * rpcdname.c
37  * Gets the default domain name
38  */
39 #include "mt.h"
40 #include "rpc_mt.h"
41 #include <sys/types.h>
42 #include <sys/time.h>
43 #include <string.h>
44 #include <syslog.h>
45 
46 extern int getdomainname();
47 extern char *strdup();
48 static char *default_domain = 0;
49 
50 static char *
51 get_default_domain(void)
52 {
53 	char temp[256];
54 	extern mutex_t dname_lock;
55 
56 /* VARIABLES PROTECTED BY dname_lock: default_domain */
57 
58 	(void) mutex_lock(&dname_lock);
59 	if (default_domain) {
60 		(void) mutex_unlock(&dname_lock);
61 		return (default_domain);
62 	}
63 	if (getdomainname(temp, (size_t)sizeof (temp)) < 0) {
64 		(void) mutex_unlock(&dname_lock);
65 		return (0);
66 	}
67 	if ((int)strlen(temp) > 0) {
68 		default_domain = strdup(temp);
69 		if (default_domain == NULL) {
70 			syslog(LOG_ERR, "get_default_domain : strdup failed.");
71 			(void) mutex_unlock(&dname_lock);
72 			return (0);
73 		}
74 	}
75 	(void) mutex_unlock(&dname_lock);
76 	return (default_domain);
77 }
78 
79 /*
80  * This is a wrapper for the system call getdomainname which returns a
81  * ypclnt.h error code in the failure case.  It also checks to see that
82  * the domain name is non-null, knowing that the null string is going to
83  * get rejected elsewhere in the yp client package.
84  */
85 int
86 __rpc_get_default_domain(char **domain)
87 {
88 	if ((*domain = get_default_domain()) != 0)
89 		return (0);
90 	return (-1);
91 }
92