xref: /freebsd/lib/libc/inet/inet_lnaof.c (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)
1*8a16b7a1SPedro F. Giffuni /*-
2*8a16b7a1SPedro F. Giffuni  * SPDX-License-Identifier: BSD-3-Clause
3*8a16b7a1SPedro F. Giffuni  *
465e96449SHajimu UMEMOTO  * Copyright (c) 1983, 1993
565e96449SHajimu UMEMOTO  *	The Regents of the University of California.  All rights reserved.
665e96449SHajimu UMEMOTO  *
765e96449SHajimu UMEMOTO  * Redistribution and use in source and binary forms, with or without
865e96449SHajimu UMEMOTO  * modification, are permitted provided that the following conditions
965e96449SHajimu UMEMOTO  * are met:
1065e96449SHajimu UMEMOTO  * 1. Redistributions of source code must retain the above copyright
1165e96449SHajimu UMEMOTO  *    notice, this list of conditions and the following disclaimer.
1265e96449SHajimu UMEMOTO  * 2. Redistributions in binary form must reproduce the above copyright
1365e96449SHajimu UMEMOTO  *    notice, this list of conditions and the following disclaimer in the
1465e96449SHajimu UMEMOTO  *    documentation and/or other materials provided with the distribution.
15fbbd9655SWarner Losh  * 3. Neither the name of the University nor the names of its contributors
1665e96449SHajimu UMEMOTO  *    may be used to endorse or promote products derived from this software
1765e96449SHajimu UMEMOTO  *    without specific prior written permission.
1865e96449SHajimu UMEMOTO  *
1965e96449SHajimu UMEMOTO  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2065e96449SHajimu UMEMOTO  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2165e96449SHajimu UMEMOTO  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2265e96449SHajimu UMEMOTO  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2365e96449SHajimu UMEMOTO  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2465e96449SHajimu UMEMOTO  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2565e96449SHajimu UMEMOTO  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2665e96449SHajimu UMEMOTO  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2765e96449SHajimu UMEMOTO  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2865e96449SHajimu UMEMOTO  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2965e96449SHajimu UMEMOTO  * SUCH DAMAGE.
3065e96449SHajimu UMEMOTO  */
3165e96449SHajimu UMEMOTO 
3265e96449SHajimu UMEMOTO #include "port_before.h"
3365e96449SHajimu UMEMOTO 
3465e96449SHajimu UMEMOTO #include <sys/param.h>
3565e96449SHajimu UMEMOTO #include <netinet/in.h>
3665e96449SHajimu UMEMOTO #include <arpa/inet.h>
3765e96449SHajimu UMEMOTO 
3865e96449SHajimu UMEMOTO #include "port_after.h"
3965e96449SHajimu UMEMOTO 
40dde4a85dSHajimu UMEMOTO /*%
4165e96449SHajimu UMEMOTO  * Return the local network address portion of an
4265e96449SHajimu UMEMOTO  * internet address; handles class a/b/c network
4365e96449SHajimu UMEMOTO  * number formats.
4465e96449SHajimu UMEMOTO  */
45ab96eeabSHajimu UMEMOTO in_addr_t
inet_lnaof(struct in_addr in)46060e5496SCraig Rodrigues inet_lnaof(struct in_addr in)
4765e96449SHajimu UMEMOTO {
48ab96eeabSHajimu UMEMOTO 	in_addr_t i = ntohl(in.s_addr);
4965e96449SHajimu UMEMOTO 
5065e96449SHajimu UMEMOTO 	if (IN_CLASSA(i))
5165e96449SHajimu UMEMOTO 		return ((i)&IN_CLASSA_HOST);
5265e96449SHajimu UMEMOTO 	else if (IN_CLASSB(i))
5365e96449SHajimu UMEMOTO 		return ((i)&IN_CLASSB_HOST);
5465e96449SHajimu UMEMOTO 	else
5565e96449SHajimu UMEMOTO 		return ((i)&IN_CLASSC_HOST);
5665e96449SHajimu UMEMOTO }
57ab96eeabSHajimu UMEMOTO 
58ab96eeabSHajimu UMEMOTO /*
59ab96eeabSHajimu UMEMOTO  * Weak aliases for applications that use certain private entry points,
60ab96eeabSHajimu UMEMOTO  * and fail to include <arpa/inet.h>.
61ab96eeabSHajimu UMEMOTO  */
62ab96eeabSHajimu UMEMOTO #undef inet_lnaof
63ab96eeabSHajimu UMEMOTO __weak_reference(__inet_lnaof, inet_lnaof);
64dde4a85dSHajimu UMEMOTO 
65dde4a85dSHajimu UMEMOTO /*! \file */
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