1  /* Copyright (C) 1993-2023 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  
      25  struct 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  };
      46  extern struct hconf _res_hconf;
      47  
      48  extern void _res_hconf_init (void) attribute_hidden;
      49  extern void _res_hconf_trim_domain (char *domain);
      50  extern void _res_hconf_trim_domains (struct hostent *hp);
      51  extern void _res_hconf_reorder_addrs (struct hostent *hp);
      52  
      53  #endif /* _RES_HCONF_H_ */