1/* Copyright (C) 1993-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#ifndef _RES_HCONF_H_
19#define _RES_HCONF_H_
20
21#include <netdb.h>
22
23#define TRIMDOMAINS_MAX 4
24
25struct hconf
26{
27 /* We keep the INITIALIZED member only for backwards compatibility. New
28 code should just call _res_hconf_init unconditionally. For this field
29 to be used safely, users must ensure that either (1) a call to
30 _res_hconf_init happens-before any load from INITIALIZED, or (2) an
31 assignment of zero to INITIALIZED happens-before any load from it, and
32 these loads use acquire MO if the intent is to skip calling
33 _res_hconf_init if the load returns a nonzero value. Such acquire MO
34 loads will then synchronize with the release MO store to INITIALIZED
35 in do_init in res_hconf.c; see pthread_once for more detail. */
36 int initialized;
37 int unused1;
38 int unused2[4];
39 int num_trimdomains;
40 const char *trimdomain[TRIMDOMAINS_MAX];
41 unsigned int flags;
42# define HCONF_FLAG_INITED (1 << 0) /* initialized? */
43# define HCONF_FLAG_REORDER (1 << 3) /* list best address first */
44# define HCONF_FLAG_MULTI (1 << 4) /* see comments for gethtbyname() */
45};
46extern struct hconf _res_hconf;
47
48extern void _res_hconf_init (void) attribute_hidden;
49extern void _res_hconf_trim_domain (char *domain);
50extern void _res_hconf_trim_domains (struct hostent *hp);
51extern void _res_hconf_reorder_addrs (struct hostent *hp);
52
53#endif /* _RES_HCONF_H_ */
54

source code of glibc/resolv/res_hconf.h