xref: /titanic_41/usr/src/lib/libresolv2/common/inet/inet_lnaof.c (revision c5024742c2f7d10880eae26cc592353b20a58f4a)
1 /*
2  * Copyright (c) 1997-2000 by Sun Microsystems, Inc.
3  * All rights reserved.
4  */
5 
6 /*
7  * Copyright (c) 1983, 1993
8  *	The Regents of the University of California.  All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 #pragma ident	"%Z%%M%	%I%	%E% SMI"
39 
40 #if defined(LIBC_SCCS) && !defined(lint)
41 static const char sccsid[] = "@(#)inet_lnaof.c	8.1 (Berkeley) 6/4/93";
42 #endif /* LIBC_SCCS and not lint */
43 
44 #include "port_before.h"
45 
46 #include <sys/param.h>
47 #include <netinet/in.h>
48 #include <arpa/inet.h>
49 
50 #include "port_after.h"
51 
52 /*
53  * Return the local network address portion of an
54  * internet address; handles class a/b/c network
55  * number formats.
56  */
57 #ifdef	ORIGINAL_ISC_CODE
58 u_long
59 #else
60 in_addr_t
61 #endif
62 inet_lnaof(in)
63 	struct in_addr in;
64 {
65 #ifdef	ORIGINAL_ISC_CODE
66 	u_long i = ntohl(in.s_addr);
67 #else
68 	in_addr_t i = ntohl(in.s_addr);
69 #endif
70 
71 	if (IN_CLASSA(i))
72 		return ((i)&IN_CLASSA_HOST);
73 	else if (IN_CLASSB(i))
74 		return ((i)&IN_CLASSB_HOST);
75 	else
76 		return ((i)&IN_CLASSC_HOST);
77 }
78