1 /* $NetBSD: inet_netof.c,v 1.1 2004/05/20 23:13:02 christos Exp $ */ 2 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 <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)inet_netof.c 8.1 (Berkeley) 6/4/93"; 36 #else 37 __RCSID("$NetBSD: inet_netof.c,v 1.1 2004/05/20 23:13:02 christos Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include <sys/param.h> 43 #include <netinet/in.h> 44 #include <arpa/inet.h> 45 46 #ifdef __weak_alias 47 __weak_alias(inet_netof,_inet_netof) 48 #endif 49 50 /* 51 * Return the network number from an internet 52 * address; handles class a/b/c network #'s. 53 */ 54 in_addr_t 55 inet_netof(struct in_addr in) 56 { 57 in_addr_t i = ntohl(in.s_addr); 58 59 if (IN_CLASSA(i)) 60 return (((i)&IN_CLASSA_NET) >> IN_CLASSA_NSHIFT); 61 else if (IN_CLASSB(i)) 62 return (((i)&IN_CLASSB_NET) >> IN_CLASSB_NSHIFT); 63 else 64 return (((i)&IN_CLASSC_NET) >> IN_CLASSC_NSHIFT); 65 } 66