xref: /illumos-gate/usr/src/lib/libresolv2/common/resolv/herror.c (revision 4da99751f967c5f8f04e17d8881a68c2940f3b06)
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