resolv/res_use_inet6.h

   1 /* Support functions for handling RES_USE_INET6 in getaddrinfo/nscd.
   2    Copyright (C) 2017-2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _RES_USE_INET6_H
  20 #define _RES_USE_INET6_H
  21
  22 #include <resolv/resolv_context.h>
  23 #include <resolv/resolv-internal.h>
  24
  25 /* Ensure that RES_USE_INET6 is disabled in *CTX.  Return true if
  26    __resolv_context_enable_inet6 below should enable RES_USE_INET6
  27    again.  */
  28 static inline bool
  29 __resolv_context_disable_inet6 (struct resolv_context *ctx)
  30 {
  31   if (ctx != NULL && ctx->resp->options & DEPRECATED_RES_USE_INET6)
  32     {
  33       ctx->resp->options &= ~DEPRECATED_RES_USE_INET6;
  34       return true;
  35     }
  36   else
  37     return false;
  38 }
  39
  40 /* If ENABLE, re-enable RES_USE_INET6 in *CTX.  To be paired with
  41    __resolv_context_disable_inet6.  */
  42 static inline void
  43 __resolv_context_enable_inet6 (struct resolv_context *ctx, bool enable)
  44 {
  45   if (ctx != NULL && enable)
  46     ctx->resp->options |= DEPRECATED_RES_USE_INET6;
  47 }
  48
  49 #endif