xref: /original-bsd/lib/libc/net/inet_makeaddr.c (revision 279692fa)
1 /*
2  * Copyright (c) 1983 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 
18 #if defined(LIBC_SCCS) && !defined(lint)
19 static char sccsid[] = "@(#)inet_makeaddr.c	5.3 (Berkeley) 06/27/88";
20 #endif /* LIBC_SCCS and not lint */
21 
22 #include <sys/types.h>
23 #include <netinet/in.h>
24 
25 /*
26  * Formulate an Internet address from network + host.  Used in
27  * building addresses stored in the ifnet structure.
28  */
29 struct in_addr
30 inet_makeaddr(net, host)
31 	int net, host;
32 {
33 	u_long addr;
34 
35 	if (net < 128)
36 		addr = (net << IN_CLASSA_NSHIFT) | (host & IN_CLASSA_HOST);
37 	else if (net < 65536)
38 		addr = (net << IN_CLASSB_NSHIFT) | (host & IN_CLASSB_HOST);
39 	else
40 		addr = (net << IN_CLASSC_NSHIFT) | (host & IN_CLASSC_HOST);
41 	addr = htonl(addr);
42 	return (*(struct in_addr *)&addr);
43 }
44