glibc/rt/bits/mqueue2.h

/* Checking macros for mq functions.
   Copyright (C) 2007-2020 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#ifndef	_FCNTL_H
# error "Never include <bits/mqueue2.h> directly; use <mqueue.h> instead."
#endif

/* Check that calls to mq_open with O_CREAT set have an appropriate third and fourth
   parameter.  */
extern mqd_t mq_open (const char *__name, int __oflag, ...)
     __THROW __nonnull ((1));
extern mqd_t __mq_open_2 (const char *__name, int __oflag)
     __THROW __nonnull ((1));
extern mqd_t __REDIRECT_NTH (__mq_open_alias, (const char *__name,
					       int __oflag, ...), mq_open)
     __nonnull ((1));
__errordecl (__mq_open_wrong_number_of_args,
	     "mq_open can be called either with 2 or 4 arguments");
__errordecl (__mq_open_missing_mode_and_attr,
	     "mq_open with O_CREAT in second argument needs 4 arguments");

__fortify_function mqd_t
__NTH (mq_open (const char *__name, int __oflag, ...))
{
  if (__va_arg_pack_len () != 0 && __va_arg_pack_len () != 2)
    __mq_open_wrong_number_of_args ();

  if (__builtin_constant_p (__oflag))
    {
      if ((__oflag & O_CREAT) != 0 && __va_arg_pack_len () == 0)
	{
	  __mq_open_missing_mode_and_attr ();
	  return __mq_open_2 (__name, __oflag);
	}
      return __mq_open_alias (__name, __oflag, __va_arg_pack ());
    }

  if (__va_arg_pack_len () == 0)
    return __mq_open_2 (__name, __oflag);

  return __mq_open_alias (__name, __oflag, __va_arg_pack ());
}