lib/libc/inet/inet_lnaof.c

   1 /*
   2  * Copyright (c) 1983, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 static const char sccsid[] = "@(#)inet_lnaof.c  8.1 (Berkeley) 6/4/93";
  32 #endif /* LIBC_SCCS and not lint */
  33
  34 #include "port_before.h"
  35
  36 #include <sys/param.h>
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39
  40 #include "port_after.h"
  41
  42 /*%
  43  * Return the local network address portion of an
  44  * internet address; handles class a/b/c network
  45  * number formats.
  46  */
  47 in_addr_t
  48 inet_lnaof(struct in_addr in)
  49 {
  50         in_addr_t i = ntohl(in.s_addr);
  51
  52         if (IN_CLASSA(i))
  53                 return ((i)&IN_CLASSA_HOST);
  54         else if (IN_CLASSB(i))
  55                 return ((i)&IN_CLASSB_HOST);
  56         else
  57                 return ((i)&IN_CLASSC_HOST);
  58 }
  59
  60 #ifdef _LIBC
  61 /*
  62  * Weak aliases for applications that use certain private entry points,
  63  * and fail to include <arpa/inet.h>.
  64  */
  65 #undef inet_lnaof
  66 __weak_reference(__inet_lnaof, inet_lnaof);
  67 #endif
  68 /*! \file */