xref: /freebsd/lib/libc/inet/inet_neta.c (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
1 /*
2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (c) 1996,1999 by Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #if defined(LIBC_SCCS) && !defined(lint)
19 static const char rcsid[] = "$Id: inet_neta.c,v 1.3 2005/04/27 04:56:20 sra Exp $";
20 #endif
21 #include <sys/cdefs.h>
22 __FBSDID("$FreeBSD$");
23 
24 #include "port_before.h"
25 
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30 
31 #include <errno.h>
32 #include <stdio.h>
33 #include <string.h>
34 
35 #include "port_after.h"
36 
37 #ifdef SPRINTF_CHAR
38 # define SPRINTF(x) strlen(sprintf/**/x)
39 #else
40 # define SPRINTF(x) ((size_t)sprintf x)
41 #endif
42 
43 /*%
44  * char *
45  * inet_neta(src, dst, size)
46  *	format an in_addr_t network number into presentation format.
47  * return:
48  *	pointer to dst, or NULL if an error occurred (check errno).
49  * note:
50  *	format of ``src'' is as for inet_network().
51  * author:
52  *	Paul Vixie (ISC), July 1996
53  */
54 char *
55 inet_neta(src, dst, size)
56 	in_addr_t src;
57 	char *dst;
58 	size_t size;
59 {
60 	char *odst = dst;
61 	char *tp;
62 
63 	while (src & 0xffffffff) {
64 		u_char b = (src & 0xff000000) >> 24;
65 
66 		src <<= 8;
67 		if (b) {
68 			if (size < sizeof "255.")
69 				goto emsgsize;
70 			tp = dst;
71 			dst += SPRINTF((dst, "%u", b));
72 			if (src != 0L) {
73 				*dst++ = '.';
74 				*dst = '\0';
75 			}
76 			size -= (size_t)(dst - tp);
77 		}
78 	}
79 	if (dst == odst) {
80 		if (size < sizeof "0.0.0.0")
81 			goto emsgsize;
82 		strcpy(dst, "0.0.0.0");
83 	}
84 	return (odst);
85 
86  emsgsize:
87 	errno = EMSGSIZE;
88 	return (NULL);
89 }
90 
91 /*
92  * Weak aliases for applications that use certain private entry points,
93  * and fail to include <arpa/inet.h>.
94  */
95 #undef inet_neta
96 __weak_reference(__inet_neta, inet_neta);
97 
98 /*! \file */
99