xref: /illumos-gate/usr/src/lib/libresolv2/common/resolv/herror.c (revision b1e2e3fb17324e9ddf43db264a0c64da7756d9e6)
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 #include "port_before.h"
52 
53 #include <sys/types.h>
54 #include <sys/param.h>
55 #include <sys/uio.h>
56 
57 #include <netinet/in.h>
58 #include <arpa/nameser.h>
59 
60 #include <netdb.h>
61 #include <resolv.h>
62 #include <string.h>
63 #include <unistd.h>
64 #include <irs.h>
65 
66 #include "port_after.h"
67 
68 const char *h_errlist[] = {
69 	"Resolver Error 0 (no error)",
70 	"Unknown host",				/*%< 1 HOST_NOT_FOUND */
71 	"Host name lookup failure",		/*%< 2 TRY_AGAIN */
72 	"Unknown server error",			/*%< 3 NO_RECOVERY */
73 	"No address associated with name",	/*%< 4 NO_ADDRESS */
74 };
75 int	h_nerr = { sizeof h_errlist / sizeof h_errlist[0] };
76 
77 #if !(__GLIBC__ > 2 || __GLIBC__ == 2 &&  __GLIBC_MINOR__ >= 3)
78 #undef	h_errno
79 int	h_errno;
80 #endif
81 
82 /*%
83  * herror --
84  *	print the error indicated by the h_errno value.
85  */
86 void
87 herror(const char *s) {
88 	struct iovec iov[4], *v = iov;
89 	char *t;
90 
91 	if (s != NULL && *s != '\0') {
92 		DE_CONST(s, t);
93 		v->iov_base = t;
94 		v->iov_len = strlen(t);
95 		v++;
96 		DE_CONST(": ", t);
97 		v->iov_base = t;
98 		v->iov_len = 2;
99 		v++;
100 	}
101 	DE_CONST(hstrerror(*__h_errno()), t);
102 	v->iov_base = t;
103 	v->iov_len = strlen(v->iov_base);
104 	v++;
105 	DE_CONST("\n", t);
106 	v->iov_base = t;
107 	v->iov_len = 1;
108 	writev(STDERR_FILENO, iov, (v - iov) + 1);
109 }
110 
111 /*%
112  * hstrerror --
113  *	return the string associated with a given "host" errno value.
114  */
115 const char *
116 hstrerror(int err) {
117 	if (err < 0)
118 		return ("Resolver internal error");
119 	else if (err < h_nerr)
120 		return (h_errlist[err]);
121 	return ("Unknown resolver error");
122 }
123 
124 /*! \file */
125