xref: /illumos-gate/usr/src/lib/libresolv2/common/inet/inet_makeaddr.c (revision 2ca5b6595b95478e6568b0e77c6c83c8a870867a)
1  /*
2   * Copyright (c) 1997-2001 by Sun Microsystems, Inc.
3   * All rights reserved.
4   */
5  
6  /*
7   * Copyright (c) 1983, 1993
8   *	The Regents of the University of California.  All rights reserved.
9   *
10   * Redistribution and use in source and binary forms, with or without
11   * modification, are permitted provided that the following conditions
12   * are met:
13   * 1. Redistributions of source code must retain the above copyright
14   *    notice, this list of conditions and the following disclaimer.
15   * 2. Redistributions in binary form must reproduce the above copyright
16   *    notice, this list of conditions and the following disclaimer in the
17   *    documentation and/or other materials provided with the distribution.
18   * 3. All advertising materials mentioning features or use of this software
19   *    must display the following acknowledgement:
20   *	This product includes software developed by the University of
21   *	California, Berkeley and its contributors.
22   * 4. Neither the name of the University nor the names of its contributors
23   *    may be used to endorse or promote products derived from this software
24   *    without specific prior written permission.
25   *
26   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36   * SUCH DAMAGE.
37   */
38  
39  #pragma ident	"%Z%%M%	%I%	%E% SMI"
40  
41  #if defined(LIBC_SCCS) && !defined(lint)
42  static const char sccsid[] = "@(#)inet_makeaddr.c	8.1 (Berkeley) 6/4/93";
43  #endif /* LIBC_SCCS and not lint */
44  
45  #include "port_before.h"
46  
47  #include <sys/param.h>
48  #include <netinet/in.h>
49  #include <arpa/inet.h>
50  
51  #include "port_after.h"
52  
53  /*
54   * Formulate an Internet address from network + host.  Used in
55   * building addresses stored in the ifnet structure.
56   */
57  struct in_addr
58  inet_makeaddr(net, host)
59  #ifdef	ORIGINAL_ISC_CODE
60  	u_long net, host;
61  #else
62  	in_addr_t net, host;
63  #endif
64  {
65  #ifdef	ORIGINAL_ISC_CODE
66  	u_long addr;
67  #else
68  	in_addr_t addr;
69  	struct in_addr inaddr;
70  #endif
71  
72  	if (net < 128)
73  		addr = (net << IN_CLASSA_NSHIFT) | (host & IN_CLASSA_HOST);
74  	else if (net < 65536)
75  		addr = (net << IN_CLASSB_NSHIFT) | (host & IN_CLASSB_HOST);
76  	else if (net < 16777216L)
77  		addr = (net << IN_CLASSC_NSHIFT) | (host & IN_CLASSC_HOST);
78  	else
79  		addr = net | host;
80  #ifdef	ORIGINAL_ISC_CODE
81  	addr = htonl(addr);
82  	return (*(struct in_addr *)&addr);
83  #else
84  	inaddr.s_addr = htonl(addr);
85  	return (inaddr);
86  #endif
87  }
88