xref: /freebsd/lib/libc/resolv/herror.c (revision 287472b39c7985d968be84ea145c3e75a3e6b875)
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 1.3.18.1 2005/04/27 05:01:09 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/types.h>
58 #include <sys/param.h>
59 #include <sys/uio.h>
60 
61 #include <netinet/in.h>
62 #include <arpa/nameser.h>
63 
64 #include <netdb.h>
65 #include <resolv.h>
66 #include <string.h>
67 #include <unistd.h>
68 #include "un-namespace.h"
69 
70 #include "port_after.h"
71 
72 const char *h_errlist[] = {
73 	"Resolver Error 0 (no error)",
74 	"Unknown host",				/*%< 1 HOST_NOT_FOUND */
75 	"Host name lookup failure",		/*%< 2 TRY_AGAIN */
76 	"Unknown server error",			/*%< 3 NO_RECOVERY */
77 	"No address associated with name",	/*%< 4 NO_ADDRESS */
78 };
79 const int h_nerr = { sizeof h_errlist / sizeof h_errlist[0] };
80 
81 #undef	h_errno
82 int	h_errno;
83 
84 /*%
85  * herror --
86  *	print the error indicated by the h_errno value.
87  */
88 void
89 herror(const char *s) {
90 	struct iovec iov[4], *v = iov;
91 	char *t;
92 
93 	if (s != NULL && *s != '\0') {
94 		DE_CONST(s, t);
95 		v->iov_base = t;
96 		v->iov_len = strlen(t);
97 		v++;
98 		DE_CONST(": ", t);
99 		v->iov_base = t;
100 		v->iov_len = 2;
101 		v++;
102 	}
103 	DE_CONST(hstrerror(*__h_errno()), t);
104 	v->iov_base = t;
105 	v->iov_len = strlen(v->iov_base);
106 	v++;
107 	DE_CONST("\n", t);
108 	v->iov_base = t;
109 	v->iov_len = 1;
110 	_writev(STDERR_FILENO, iov, (v - iov) + 1);
111 }
112 
113 /*%
114  * hstrerror --
115  *	return the string associated with a given "host" errno value.
116  */
117 const char *
118 hstrerror(int err) {
119 	if (err < 0)
120 		return ("Resolver internal error");
121 	else if (err < h_nerr)
122 		return (h_errlist[err]);
123 	return ("Unknown resolver error");
124 }
125 
126 /*! \file */
127