xref: /titanic_44/usr/src/lib/libbc/libc/inet/inet_lnaof.c (revision 2b4a78020b9c38d1b95e2f3fefa6d6e4be382d1f)
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  * Copyright 1983 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <netinet/in.h>
31 
32 /*
33  * Return the local network address portion of an
34  * internet address; handles class a/b/c network
35  * number formats.
36  */
37 int
38 inet_lnaof(struct in_addr in)
39 {
40 	u_long i = ntohl(in.s_addr);
41 
42 	if (IN_CLASSA(i))
43 		return ((i)&IN_CLASSA_HOST);
44 	else if (IN_CLASSB(i))
45 		return ((i)&IN_CLASSB_HOST);
46 	else
47 		return ((i)&IN_CLASSC_HOST);
48 }
49