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
60const 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};
67const int	h_nerr = { sizeof h_errlist / sizeof h_errlist[0] };
68
69extern int	h_errno;
70
71/*
72 * herror --
73 *	print the error indicated by the h_errno value.
74 */
75void
76herror(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
97const char *
98hstrerror(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}
106DEF_WEAK(hstrerror);
107