getnameinfo.c revision 233294 
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#include <config.h>
35
36#include "roken.h"
37
38static int
39doit (int af,
40      const void *addr,
41      size_t addrlen,
42      int port,
43      char *host, size_t hostlen,
44      char *serv, size_t servlen,
45      int flags)
46{
47    if (host != NULL) {
48	if (flags & NI_NUMERICHOST) {
49	    if (inet_ntop (af, addr, host, hostlen) == NULL)
50		return EAI_SYSTEM;
51	} else {
52	    struct hostent *he = gethostbyaddr (addr,
53						addrlen,
54						af);
55	    if (he != NULL) {
56		strlcpy (host, hostent_find_fqdn(he), hostlen);
57		if (flags & NI_NOFQDN) {
58		    char *dot = strchr (host, '.');
59		    if (dot != NULL)
60			*dot = '\0';
61		}
62	    } else if (flags & NI_NAMEREQD) {
63		return EAI_NONAME;
64	    } else if (inet_ntop (af, addr, host, hostlen) == NULL)
65		return EAI_SYSTEM;
66	}
67    }
68
69    if (serv != NULL) {
70	if (flags & NI_NUMERICSERV) {
71	    snprintf (serv, servlen, "%u", ntohs(port));
72	} else {
73	    const char *proto = "tcp";
74	    struct servent *se;
75
76	    if (flags & NI_DGRAM)
77		proto = "udp";
78
79	    se = getservbyport (port, proto);
80	    if (se == NULL) {
81		snprintf (serv, servlen, "%u", ntohs(port));
82	    } else {
83		strlcpy (serv, se->s_name, servlen);
84	    }
85	}
86    }
87    return 0;
88}
89
90/*
91 *
92 */
93
94ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
95getnameinfo(const struct sockaddr *sa, socklen_t salen,
96	    char *host, size_t hostlen,
97	    char *serv, size_t servlen,
98	    int flags)
99{
100    switch (sa->sa_family) {
101#ifdef HAVE_IPV6
102    case AF_INET6 : {
103	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
104
105	return doit (AF_INET6, &sin6->sin6_addr, sizeof(sin6->sin6_addr),
106		     sin6->sin6_port,
107		     host, hostlen,
108		     serv, servlen,
109		     flags);
110    }
111#endif
112    case AF_INET : {
113	const struct sockaddr_in *sin4 = (const struct sockaddr_in *)sa;
114
115	return doit (AF_INET, &sin4->sin_addr, sizeof(sin4->sin_addr),
116		     sin4->sin_port,
117		     host, hostlen,
118		     serv, servlen,
119		     flags);
120    }
121    default :
122	return EAI_FAMILY;
123    }
124}
125