inet/inet_mkadr.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  * 4. 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 #include <sys/param.h>
  31 #include <netinet/in.h>
  32 #include <arpa/inet.h>
  33
  34 /*
  35  * Formulate an Internet address from network + host.  Used in
  36  * building addresses stored in the ifnet structure.
  37  */
  38 struct in_addr
  39 __inet_makeaddr (in_addr_t net, in_addr_t host)
  40 {
  41         struct in_addr in;
  42
  43         if (net < 128)
  44                 in.s_addr = (net << IN_CLASSA_NSHIFT) | (host & IN_CLASSA_HOST);
  45         else if (net < 65536)
  46                 in.s_addr = (net << IN_CLASSB_NSHIFT) | (host & IN_CLASSB_HOST);
  47         else if (net < 16777216L)
  48                 in.s_addr = (net << IN_CLASSC_NSHIFT) | (host & IN_CLASSC_HOST);
  49         else
  50                 in.s_addr = net | host;
  51         in.s_addr = htonl(in.s_addr);
  52         return in;
  53 }
  54 libc_hidden_def (__inet_makeaddr)
  55 weak_alias (__inet_makeaddr, inet_makeaddr)