xref: /freebsd/lib/libc/resolv/herror.c (revision 3fc36ee018bb836bd1796067cf4ef8683f166ebc)
1 /*
2  * Copyright (c) 1987, 1993
3  *    The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /*
31  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
32  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
33  *
34  * Permission to use, copy, modify, and distribute this software for any
35  * purpose with or without fee is hereby granted, provided that the above
36  * copyright notice and this permission notice appear in all copies.
37  *
38  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
39  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
40  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
41  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
42  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
43  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
44  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
45  */
46 
47 #if defined(LIBC_SCCS) && !defined(lint)
48 static const char sccsid[] = "@(#)herror.c	8.1 (Berkeley) 6/4/93";
49 static const char rcsid[] = "$Id: herror.c,v 1.4 2005/04/27 04:56:41 sra Exp $";
50 #endif /* LIBC_SCCS and not lint */
51 #include <sys/cdefs.h>
52 __FBSDID("$FreeBSD$");
53 
54 #include "port_before.h"
55 
56 #include "namespace.h"
57 #include <sys/param.h>
58 #include <sys/uio.h>
59 
60 #include <netinet/in.h>
61 #include <arpa/nameser.h>
62 
63 #include <netdb.h>
64 #include <resolv.h>
65 #include <string.h>
66 #include <unistd.h>
67 #include "un-namespace.h"
68 
69 #include "port_after.h"
70 
71 const char *h_errlist[] = {
72 	"Resolver Error 0 (no error)",
73 	"Unknown host",				/*%< 1 HOST_NOT_FOUND */
74 	"Host name lookup failure",		/*%< 2 TRY_AGAIN */
75 	"Unknown server error",			/*%< 3 NO_RECOVERY */
76 	"No address associated with name",	/*%< 4 NO_ADDRESS */
77 };
78 const int h_nerr = { nitems(h_errlist) };
79 
80 #undef	h_errno
81 int	h_errno;
82 
83 /*%
84  * herror --
85  *	print the error indicated by the h_errno value.
86  */
87 void
88 herror(const char *s) {
89 	struct iovec iov[4], *v = iov;
90 	char *t;
91 
92 	if (s != NULL && *s != '\0') {
93 		DE_CONST(s, t);
94 		v->iov_base = t;
95 		v->iov_len = strlen(t);
96 		v++;
97 		DE_CONST(": ", t);
98 		v->iov_base = t;
99 		v->iov_len = 2;
100 		v++;
101 	}
102 	DE_CONST(hstrerror(*__h_errno()), t);
103 	v->iov_base = t;
104 	v->iov_len = strlen(v->iov_base);
105 	v++;
106 	DE_CONST("\n", t);
107 	v->iov_base = t;
108 	v->iov_len = 1;
109 	_writev(STDERR_FILENO, iov, (v - iov) + 1);
110 }
111 
112 /*%
113  * hstrerror --
114  *	return the string associated with a given "host" errno value.
115  */
116 const char *
117 hstrerror(int err) {
118 	if (err < 0)
119 		return ("Resolver internal error");
120 	else if (err < h_nerr)
121 		return (h_errlist[err]);
122 	return ("Unknown resolver error");
123 }
124 
125 /*! \file */
126