# Check if "struct ucred" is available.  If not, try harder with
# _GNU_SOURCE.
#
# Author: Max Kellermann <max@duempel.org>

AC_DEFUN([STRUCT_UCRED],[
	AC_MSG_CHECKING([for struct ucred])
	AC_CACHE_VAL(mpd_cv_have_struct_ucred, [
		AC_TRY_COMPILE([#include <sys/socket.h>],
			[struct ucred cred;],
			mpd_cv_have_struct_ucred=yes,
			mpd_cv_have_struct_ucred=no)
		if test x$mpd_cv_have_struct_ucred = xno; then
			# glibc 2.8 forces _GNU_SOURCE on us
			AC_TRY_COMPILE(
				[#define _GNU_SOURCE
				 #include <sys/socket.h>],
				[struct ucred cred;],
				mpd_cv_have_struct_ucred=yes,
				mpd_cv_have_struct_ucred=no)
			if test x$mpd_cv_have_struct_ucred = xyes; then
				# :(
				CFLAGS="$CFLAGS -D_GNU_SOURCE"
			fi
		fi
		])

	AC_MSG_RESULT($mpd_cv_have_struct_ucred)
	if test x$mpd_cv_have_struct_ucred = xyes; then
		AC_DEFINE(HAVE_STRUCT_UCRED, 1, [Define if struct ucred is present from sys/socket.h])
	fi
])