getnameinfo.c revision 178825 
1/*
2 * Copyright (c) 1999 - 2001 Kungliga Tekniska H�gskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifdef HAVE_CONFIG_H
35#include <config.h>
36RCSID("$Id: getnameinfo.c 15412 2005-06-16 16:53:09Z lha $");
37#endif
38
39#include "roken.h"
40
41static int
42doit (int af,
43      const void *addr,
44      size_t addrlen,
45      int port,
46      char *host, size_t hostlen,
47      char *serv, size_t servlen,
48      int flags)
49{
50    if (host != NULL) {
51	if (flags & NI_NUMERICHOST) {
52	    if (inet_ntop (af, addr, host, hostlen) == NULL)
53		return EAI_SYSTEM;
54	} else {
55	    struct hostent *he = gethostbyaddr (addr,
56						addrlen,
57						af);
58	    if (he != NULL) {
59		strlcpy (host, hostent_find_fqdn(he), hostlen);
60		if (flags & NI_NOFQDN) {
61		    char *dot = strchr (host, '.');
62		    if (dot != NULL)
63			*dot = '\0';
64		}
65	    } else if (flags & NI_NAMEREQD) {
66		return EAI_NONAME;
67	    } else if (inet_ntop (af, addr, host, hostlen) == NULL)
68		return EAI_SYSTEM;
69	}
70    }
71
72    if (serv != NULL) {
73	if (flags & NI_NUMERICSERV) {
74	    snprintf (serv, servlen, "%u", ntohs(port));
75	} else {
76	    const char *proto = "tcp";
77	    struct servent *se;
78
79	    if (flags & NI_DGRAM)
80		proto = "udp";
81
82	    se = getservbyport (port, proto);
83	    if (se == NULL) {
84		snprintf (serv, servlen, "%u", ntohs(port));
85	    } else {
86		strlcpy (serv, se->s_name, servlen);
87	    }
88	}
89    }
90    return 0;
91}
92
93/*
94 *
95 */
96
97int ROKEN_LIB_FUNCTION
98getnameinfo(const struct sockaddr *sa, socklen_t salen,
99	    char *host, size_t hostlen,
100	    char *serv, size_t servlen,
101	    int flags)
102{
103    switch (sa->sa_family) {
104#ifdef HAVE_IPV6
105    case AF_INET6 : {
106	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
107
108	return doit (AF_INET6, &sin6->sin6_addr, sizeof(sin6->sin6_addr),
109		     sin6->sin6_port,
110		     host, hostlen,
111		     serv, servlen,
112		     flags);
113    }
114#endif
115    case AF_INET : {
116	const struct sockaddr_in *sin4 = (const struct sockaddr_in *)sa;
117
118	return doit (AF_INET, &sin4->sin_addr, sizeof(sin4->sin_addr),
119		     sin4->sin_port,
120		     host, hostlen,
121		     serv, servlen,
122		     flags);
123    }
124    default :
125	return EAI_FAMILY;
126    }
127}
128