m4/st_bpf.m4

#!/usr/bin/m4
#
# Copyright (c) 2015-2017 Dmitry V. Levin <ldv@altlinux.org>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. The name of the author may not be used to endorse or promote products
#    derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

AC_DEFUN([st_CHECK_UNION_BPF_ATTR],[

pushdef([ATTR_NAME], translit([$1], [a-z], [A-Z]))
pushdef([attr_text], [union bpf_attr.][$1])
pushdef([have_attr], [st_cv_member_union_bpf_attr_][$1])

AC_CACHE_CHECK([whether attr_text initialization works],
	       [have_attr],
	       [AC_COMPILE_IFELSE(
		[AC_LANG_PROGRAM([[#include <linux/bpf.h>]],
				 [union bpf_attr a = { .$1 = 0 };])],
		[have_attr=yes],
		[have_attr=no])])

if test $have_attr = yes; then
	AC_DEFINE([HAVE_UNION_BPF_ATTR_]ATTR_NAME, [1],
		  [Define to 1 if attr_text initialization works])
fi

popdef([have_attr])
popdef([attr_text])
popdef([ATTR_NAME])
])