# ===========================================================================

#     https://www.gnu.org/software/autoconf-archive/ax_check_define.html

# ===========================================================================

#

# SYNOPSIS

#

#   AC_CHECK_DEFINE([symbol], [ACTION-IF-FOUND], [ACTION-IF-NOT])

#   AX_CHECK_DEFINE([includes],[symbol], [ACTION-IF-FOUND], [ACTION-IF-NOT])

#

# DESCRIPTION

#

#   Complements AC_CHECK_FUNC but it does not check for a function but for a

#   define to exist. Consider a usage like:

#

#    AC_CHECK_DEFINE(__STRICT_ANSI__, CFLAGS="$CFLAGS -D_XOPEN_SOURCE=500")

#

# LICENSE

#

#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>

#

#   This program is free software; you can redistribute it and/or modify it

#   under the terms of the GNU General Public License as published by the

#   Free Software Foundation; either version 3 of the License, or (at your

#   option) any later version.

#

#   This program 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 General

#   Public License for more details.

#

#   You should have received a copy of the GNU General Public License along

#   with this program. If not, see <https://www.gnu.org/licenses/>.

#

#   As a special exception, the respective Autoconf Macro's copyright owner

#   gives unlimited permission to copy, distribute and modify the configure

#   scripts that are the output of Autoconf when processing the Macro. You

#   need not follow the terms of the GNU General Public License when using

#   or distributing such scripts, even though portions of the text of the

#   Macro appear in them. The GNU General Public License (GPL) does govern

#   all other use of the material that constitutes the Autoconf Macro.

#

#   This special exception to the GPL applies to versions of the Autoconf

#   Macro released by the Autoconf Archive. When you make and distribute a

#   modified version of the Autoconf Macro, you may extend this special

#   exception to the GPL to apply to your modified version as well.

#serial 9

AU_ALIAS([AC_CHECK_DEFINED], [AC_CHECK_DEFINE])

AC_DEFUN([AC_CHECK_DEFINE],[

AS_VAR_PUSHDEF([ac_var],[ac_cv_defined_$1])dnl

AC_CACHE_CHECK([for $1 defined], ac_var,

AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[

  #ifdef $1

  int ok;

  #else

  choke me

  #endif

]])],[AS_VAR_SET(ac_var, yes)],[AS_VAR_SET(ac_var, no)]))

AS_IF([test AS_VAR_GET(ac_var) != "no"], [$2], [$3])dnl

AS_VAR_POPDEF([ac_var])dnl

])

AU_ALIAS([AX_CHECK_DEFINED], [AX_CHECK_DEFINE])

AC_DEFUN([AX_CHECK_DEFINE],[

AS_VAR_PUSHDEF([ac_var],[ac_cv_defined_$2_$1])dnl

AC_CACHE_CHECK([for $2 defined in $1], ac_var,

AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <$1>]], [[

  #ifdef $2

  int ok;

  #else

  choke me

  #endif

]])],[AS_VAR_SET(ac_var, yes)],[AS_VAR_SET(ac_var, no)]))

AS_IF([test AS_VAR_GET(ac_var) != "no"], [$3], [$4])dnl

AS_VAR_POPDEF([ac_var])dnl

])

AC_DEFUN([AX_CHECK_FUNC],

[AS_VAR_PUSHDEF([ac_var], [ac_cv_func_$2])dnl

AC_CACHE_CHECK([for $2], ac_var,

dnl AC_LANG_FUNC_LINK_TRY

[AC_LINK_IFELSE([AC_LANG_PROGRAM([$1

                #undef $2

                char $2 ();],[

                char (*f) () = $2;

                return f != $2; ])],

                [AS_VAR_SET(ac_var, yes)],

                [AS_VAR_SET(ac_var, no)])])

AS_IF([test AS_VAR_GET(ac_var) = yes], [$3], [$4])dnl

AS_VAR_POPDEF([ac_var])dnl

])# AC_CHECK_FUNC