xref: /freebsd/lib/libc/inet/inet_lnaof.c (revision dde4a85d9ddb5d516c37a565156ef509738c3c22)
165e96449SHajimu UMEMOTO /*
265e96449SHajimu UMEMOTO  * Copyright (c) 1983, 1993
365e96449SHajimu UMEMOTO  *	The Regents of the University of California.  All rights reserved.
465e96449SHajimu UMEMOTO  *
565e96449SHajimu UMEMOTO  * Redistribution and use in source and binary forms, with or without
665e96449SHajimu UMEMOTO  * modification, are permitted provided that the following conditions
765e96449SHajimu UMEMOTO  * are met:
865e96449SHajimu UMEMOTO  * 1. Redistributions of source code must retain the above copyright
965e96449SHajimu UMEMOTO  *    notice, this list of conditions and the following disclaimer.
1065e96449SHajimu UMEMOTO  * 2. Redistributions in binary form must reproduce the above copyright
1165e96449SHajimu UMEMOTO  *    notice, this list of conditions and the following disclaimer in the
1265e96449SHajimu UMEMOTO  *    documentation and/or other materials provided with the distribution.
1365e96449SHajimu UMEMOTO  * 4. Neither the name of the University nor the names of its contributors
1465e96449SHajimu UMEMOTO  *    may be used to endorse or promote products derived from this software
1565e96449SHajimu UMEMOTO  *    without specific prior written permission.
1665e96449SHajimu UMEMOTO  *
1765e96449SHajimu UMEMOTO  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
1865e96449SHajimu UMEMOTO  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1965e96449SHajimu UMEMOTO  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2065e96449SHajimu UMEMOTO  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2165e96449SHajimu UMEMOTO  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2265e96449SHajimu UMEMOTO  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2365e96449SHajimu UMEMOTO  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2465e96449SHajimu UMEMOTO  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2565e96449SHajimu UMEMOTO  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2665e96449SHajimu UMEMOTO  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2765e96449SHajimu UMEMOTO  * SUCH DAMAGE.
2865e96449SHajimu UMEMOTO  */
2965e96449SHajimu UMEMOTO 
3065e96449SHajimu UMEMOTO #if defined(LIBC_SCCS) && !defined(lint)
3165e96449SHajimu UMEMOTO static const char sccsid[] = "@(#)inet_lnaof.c	8.1 (Berkeley) 6/4/93";
3265e96449SHajimu UMEMOTO #endif /* LIBC_SCCS and not lint */
33ab96eeabSHajimu UMEMOTO #include <sys/cdefs.h>
34ab96eeabSHajimu UMEMOTO __FBSDID("$FreeBSD$");
3565e96449SHajimu UMEMOTO 
3665e96449SHajimu UMEMOTO #include "port_before.h"
3765e96449SHajimu UMEMOTO 
3865e96449SHajimu UMEMOTO #include <sys/param.h>
3965e96449SHajimu UMEMOTO #include <netinet/in.h>
4065e96449SHajimu UMEMOTO #include <arpa/inet.h>
4165e96449SHajimu UMEMOTO 
4265e96449SHajimu UMEMOTO #include "port_after.h"
4365e96449SHajimu UMEMOTO 
44dde4a85dSHajimu UMEMOTO /*%
4565e96449SHajimu UMEMOTO  * Return the local network address portion of an
4665e96449SHajimu UMEMOTO  * internet address; handles class a/b/c network
4765e96449SHajimu UMEMOTO  * number formats.
4865e96449SHajimu UMEMOTO  */
49ab96eeabSHajimu UMEMOTO in_addr_t
5065e96449SHajimu UMEMOTO inet_lnaof(in)
5165e96449SHajimu UMEMOTO 	struct in_addr in;
5265e96449SHajimu UMEMOTO {
53ab96eeabSHajimu UMEMOTO 	in_addr_t i = ntohl(in.s_addr);
5465e96449SHajimu UMEMOTO 
5565e96449SHajimu UMEMOTO 	if (IN_CLASSA(i))
5665e96449SHajimu UMEMOTO 		return ((i)&IN_CLASSA_HOST);
5765e96449SHajimu UMEMOTO 	else if (IN_CLASSB(i))
5865e96449SHajimu UMEMOTO 		return ((i)&IN_CLASSB_HOST);
5965e96449SHajimu UMEMOTO 	else
6065e96449SHajimu UMEMOTO 		return ((i)&IN_CLASSC_HOST);
6165e96449SHajimu UMEMOTO }
62ab96eeabSHajimu UMEMOTO 
63ab96eeabSHajimu UMEMOTO /*
64ab96eeabSHajimu UMEMOTO  * Weak aliases for applications that use certain private entry points,
65ab96eeabSHajimu UMEMOTO  * and fail to include <arpa/inet.h>.
66ab96eeabSHajimu UMEMOTO  */
67ab96eeabSHajimu UMEMOTO #undef inet_lnaof
68ab96eeabSHajimu UMEMOTO __weak_reference(__inet_lnaof, inet_lnaof);
69dde4a85dSHajimu UMEMOTO 
70dde4a85dSHajimu UMEMOTO /*! \file */
71