getipnodebyname.c revision 55682 
1/*
2 * Copyright (c) 1999 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: getipnodebyname.c,v 1.3 1999/12/02 16:58:46 joda Exp $");
37#endif
38
39#include "roken.h"
40
41#ifndef HAVE_H_ERRNO
42static int h_errno = NO_RECOVERY;
43#endif
44
45/*
46 * lookup `name' (address family `af') in DNS and return a pointer
47 * to a malloced struct hostent or NULL.
48 */
49
50struct hostent *
51getipnodebyname (const char *name, int af, int flags, int *error_num)
52{
53    struct hostent *tmp;
54
55#ifdef HAVE_GETHOSTBYNAME2
56    tmp = gethostbyname2 (name, af);
57#else
58    if (af != AF_INET) {
59	*error_num = NO_ADDRESS;
60	return NULL;
61    }
62    tmp = gethostbyname (name);
63#endif
64    if (tmp == NULL) {
65	switch (h_errno) {
66	case HOST_NOT_FOUND :
67	case TRY_AGAIN :
68	case NO_RECOVERY :
69	    *error_num = h_errno;
70	    break;
71	case NO_DATA :
72	    *error_num = NO_ADDRESS;
73	    break;
74	default :
75	    *error_num = NO_RECOVERY;
76	    break;
77	}
78	return NULL;
79    }
80    tmp = copyhostent (tmp);
81    if (tmp == NULL) {
82	*error_num = TRY_AGAIN;
83	return NULL;
84    }
85    return tmp;
86}
87