rt/bits/mqueue2.h

   1 /* Checking macros for mq functions.
   2    Copyright (C) 2007 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _FCNTL_H
  21 # error "Never include <bits/mqueue2.h> directly; use <mqueue.h> instead."
  22 #endif
  23
  24 /* Check that calls to mq_open with O_CREAT set have an appropriate third and fourth
  25    parameter.  */
  26 extern mqd_t mq_open (__const char *__name, int __oflag, ...)
  27      __THROW __nonnull ((1));
  28 extern mqd_t __mq_open_2 (__const char *__name, int __oflag) __nonnull ((1));
  29 extern mqd_t __REDIRECT (__mq_open_alias, (__const char *__name, int __oflag, ...),
  30                          mq_open) __nonnull ((1));
  31 __errordecl (__mq_open_wrong_number_of_args,
  32              "mq_open can be called either with 2 or 4 arguments");
  33 __errordecl (__mq_open_missing_mode_and_attr,
  34              "mq_open with O_CREAT in second argument needs 4 arguments");
  35
  36 __extern_always_inline mqd_t
  37 mq_open (__const char *__name, int __oflag, ...)
  38 {
  39   if (__va_arg_pack_len () != 0 && __va_arg_pack_len () != 2)
  40     __mq_open_wrong_number_of_args ();
  41
  42   if (__builtin_constant_p (__oflag))
  43     {
  44       if ((__oflag & O_CREAT) != 0 && __va_arg_pack_len () == 0)
  45         {
  46           __mq_open_missing_mode_and_attr ();
  47           return __mq_open_2 (__name, __oflag);
  48         }
  49       return __mq_open_alias (__name, __oflag, __va_arg_pack ());
  50     }
  51
  52   if (__va_arg_pack_len () == 0)
  53     return __mq_open_2 (__name, __oflag);
  54
  55   return __mq_open_alias (__name, __oflag, __va_arg_pack ());
  56 }