xref: /freebsd/lib/libc/resolv/herror.c (revision e4e9813eb92cd7c4d4b819a8fbed5cbd3d92f5d8)
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  * 	This product includes software developed by the University of
16  * 	California, Berkeley and its contributors.
17  * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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 /*
35  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
36  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
37  *
38  * Permission to use, copy, modify, and distribute this software for any
39  * purpose with or without fee is hereby granted, provided that the above
40  * copyright notice and this permission notice appear in all copies.
41  *
42  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
43  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
44  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
45  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
46  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
47  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
48  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
49  */
50 
51 #if defined(LIBC_SCCS) && !defined(lint)
52 static const char sccsid[] = "@(#)herror.c	8.1 (Berkeley) 6/4/93";
53 static const char rcsid[] = "$Id: herror.c,v 1.2.206.1 2004/03/09 08:33:54 marka Exp $";
54 #endif /* LIBC_SCCS and not lint */
55 #include <sys/cdefs.h>
56 __FBSDID("$FreeBSD$");
57 
58 #include "port_before.h"
59 
60 #include "namespace.h"
61 #include <sys/types.h>
62 #include <sys/param.h>
63 #include <sys/uio.h>
64 
65 #include <netinet/in.h>
66 #include <arpa/nameser.h>
67 
68 #include <netdb.h>
69 #include <resolv.h>
70 #include <string.h>
71 #include <unistd.h>
72 #include "un-namespace.h"
73 
74 #include "port_after.h"
75 
76 const char *h_errlist[] = {
77 	"Resolver Error 0 (no error)",
78 	"Unknown host",				/* 1 HOST_NOT_FOUND */
79 	"Host name lookup failure",		/* 2 TRY_AGAIN */
80 	"Unknown server error",			/* 3 NO_RECOVERY */
81 	"No address associated with name",	/* 4 NO_ADDRESS */
82 };
83 const int h_nerr = { sizeof h_errlist / sizeof h_errlist[0] };
84 
85 #undef	h_errno
86 int	h_errno;
87 
88 /*
89  * herror --
90  *	print the error indicated by the h_errno value.
91  */
92 void
93 herror(const char *s) {
94 	struct iovec iov[4], *v = iov;
95 	char *t;
96 
97 	if (s != NULL && *s != '\0') {
98 		DE_CONST(s, t);
99 		v->iov_base = t;
100 		v->iov_len = strlen(t);
101 		v++;
102 		DE_CONST(": ", t);
103 		v->iov_base = t;
104 		v->iov_len = 2;
105 		v++;
106 	}
107 	DE_CONST(hstrerror(*__h_errno()), t);
108 	v->iov_base = t;
109 	v->iov_len = strlen(v->iov_base);
110 	v++;
111 	DE_CONST("\n", t);
112 	v->iov_base = t;
113 	v->iov_len = 1;
114 	_writev(STDERR_FILENO, iov, (v - iov) + 1);
115 }
116 
117 /*
118  * hstrerror --
119  *	return the string associated with a given "host" errno value.
120  */
121 const char *
122 hstrerror(int err) {
123 	if (err < 0)
124 		return ("Resolver internal error");
125 	else if (err < h_nerr)
126 		return (h_errlist[err]);
127 	return ("Unknown resolver error");
128 }
129