1 /* $OpenBSD: herror.c,v 1.10 2015/09/14 07:38:38 guenther Exp $ */
2
3 /*
4 * ++Copyright++ 1987, 1993
5 * -
6 * Copyright (c) 1987, 1993
7 * The Regents of the University of California. All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. 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 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
34 *
35 * Permission to use, copy, modify, and distribute this software for any
36 * purpose with or without fee is hereby granted, provided that the above
37 * copyright notice and this permission notice appear in all copies, and that
38 * the name of Digital Equipment Corporation not be used in advertising or
39 * publicity pertaining to distribution of the document or software without
40 * specific, written prior permission.
41 *
42 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
43 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
44 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
45 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
46 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
47 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
48 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
49 * SOFTWARE.
50 * -
51 * --Copyright--
52 */
53
54 #include <sys/types.h>
55 #include <sys/uio.h>
56 #include <netdb.h>
57 #include <unistd.h>
58 #include <string.h>
59
60 const char * const h_errlist[] = {
61 "Resolver Error 0 (no error)",
62 "Unknown host", /* 1 HOST_NOT_FOUND */
63 "Host name lookup failure", /* 2 TRY_AGAIN */
64 "Unknown server error", /* 3 NO_RECOVERY */
65 "No address associated with name", /* 4 NO_ADDRESS */
66 };
67 const int h_nerr = { sizeof h_errlist / sizeof h_errlist[0] };
68
69 extern int h_errno;
70
71 /*
72 * herror --
73 * print the error indicated by the h_errno value.
74 */
75 void
herror(const char * s)76 herror(const char *s)
77 {
78 struct iovec iov[4];
79 struct iovec *v = iov;
80
81 if (s && *s) {
82 v->iov_base = (char *)s;
83 v->iov_len = strlen(s);
84 v++;
85 v->iov_base = ": ";
86 v->iov_len = 2;
87 v++;
88 }
89 v->iov_base = (char *)hstrerror(h_errno);
90 v->iov_len = strlen(v->iov_base);
91 v++;
92 v->iov_base = "\n";
93 v->iov_len = 1;
94 writev(STDERR_FILENO, iov, (v - iov) + 1);
95 }
96
97 const char *
hstrerror(int err)98 hstrerror(int err)
99 {
100 if (err < 0)
101 return ("Resolver internal error");
102 else if (err < h_nerr)
103 return (h_errlist[err]);
104 return ("Unknown resolver error");
105 }
106 DEF_WEAK(hstrerror);
107