xref: /csrg-svn/lib/libc/net/inet_lnaof.c (revision 42626)
121368Sdist /*
221368Sdist  * Copyright (c) 1983 Regents of the University of California.
333676Sbostic  * All rights reserved.
433676Sbostic  *
5*42626Sbostic  * %sccs.include.redist.c%
621368Sdist  */
78358Ssam 
826613Sdonn #if defined(LIBC_SCCS) && !defined(lint)
9*42626Sbostic static char sccsid[] = "@(#)inet_lnaof.c	5.6 (Berkeley) 06/01/90";
1033676Sbostic #endif /* LIBC_SCCS and not lint */
1121368Sdist 
128358Ssam #include <sys/types.h>
139192Ssam #include <netinet/in.h>
148358Ssam 
158358Ssam /*
168358Ssam  * Return the local network address portion of an
178358Ssam  * internet address; handles class a/b/c network
188358Ssam  * number formats.
198358Ssam  */
2032317Sbostic u_long
218370Ssam inet_lnaof(in)
228358Ssam 	struct in_addr in;
238358Ssam {
249192Ssam 	register u_long i = ntohl(in.s_addr);
259192Ssam 
269192Ssam 	if (IN_CLASSA(i))
279192Ssam 		return ((i)&IN_CLASSA_HOST);
289192Ssam 	else if (IN_CLASSB(i))
299192Ssam 		return ((i)&IN_CLASSB_HOST);
309192Ssam 	else
319192Ssam 		return ((i)&IN_CLASSC_HOST);
328358Ssam }
33