xref: /freebsd/lib/libc/inet/inet_makeaddr.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include "port_before.h"
33 
34 #include <sys/param.h>
35 #include <netinet/in.h>
36 #include <arpa/inet.h>
37 
38 #include "port_after.h"
39 
40 /*%
41  * Formulate an Internet address from network + host.  Used in
42  * building addresses stored in the ifnet structure.
43  */
44 struct in_addr
45 inet_makeaddr(in_addr_t net, in_addr_t host)
46 {
47 	struct in_addr a;
48 
49 	if (net < 128U)
50 		a.s_addr = (net << IN_CLASSA_NSHIFT) | (host & IN_CLASSA_HOST);
51 	else if (net < 65536U)
52 		a.s_addr = (net << IN_CLASSB_NSHIFT) | (host & IN_CLASSB_HOST);
53 	else if (net < 16777216L)
54 		a.s_addr = (net << IN_CLASSC_NSHIFT) | (host & IN_CLASSC_HOST);
55 	else
56 		a.s_addr = net | host;
57 	a.s_addr = htonl(a.s_addr);
58 	return (a);
59 }
60 
61 /*
62  * Weak aliases for applications that use certain private entry points,
63  * and fail to include <arpa/inet.h>.
64  */
65 #undef inet_makeaddr
66 __weak_reference(__inet_makeaddr, inet_makeaddr);
67 
68 /*! \file */
69