nss/gethstbyad_r.c

   1 /* Copyright (C) 1996-2024 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 #include <netdb.h>
  19 #include <string.h>
  20 #include <resolv/res_hconf.h>
  21
  22 #define LOOKUP_TYPE     struct hostent
  23 #define FUNCTION_NAME   gethostbyaddr
  24 #define DATABASE_NAME   hosts
  25 #define ADD_PARAMS      const void *addr, socklen_t len, int type
  26 #define ADD_VARIABLES   addr, len, type
  27 #define NEED_H_ERRNO    1
  28 #define NEED__RES       1
  29 /* If the addr parameter is the IPv6 unspecified address no query must
  30    be performed.  */
  31 #define PREPROCESS \
  32   if (len == sizeof (struct in6_addr)                                         \
  33       && __builtin_expect (memcmp (&__in6addr_any, addr,                      \
  34                                    sizeof (struct in6_addr)), 1) == 0)        \
  35     {                                                                         \
  36       *h_errnop = HOST_NOT_FOUND;                                             \
  37       *result = NULL;                                                         \
  38       return ENOENT;                                                          \
  39     }
  40 #define POSTPROCESS \
  41   if (status == NSS_STATUS_SUCCESS)                                           \
  42     {                                                                         \
  43       _res_hconf_reorder_addrs (resbuf);                                      \
  44       _res_hconf_trim_domains (resbuf);                                       \
  45     }
  46
  47 /* Special name for the lookup function.  */
  48 #define DB_LOOKUP_FCT __nss_hosts_lookup2
  49
  50 #include "../nss/getXXbyYY_r.c"