#                                               -*- Autoconf -*-
# Process this file with autoconf to produce a configure script.
AC_PREREQ(2.56)
sinclude(acx_nlnetlabs.m4)
sinclude(ax_pthread.m4)
sinclude(acx_python.m4)
sinclude(ac_pkg_swig.m4)
sinclude(dnstap/dnstap.m4)
sinclude(dnscrypt/dnscrypt.m4)

# must be numbers. ac_defun because of later processing
m4_define([VERSION_MAJOR],[1])
m4_define([VERSION_MINOR],[9])
m4_define([VERSION_MICRO],[4])
AC_INIT(unbound, m4_defn([VERSION_MAJOR]).m4_defn([VERSION_MINOR]).m4_defn([VERSION_MICRO]), unbound-bugs@nlnetlabs.nl or https://github.com/NLnetLabs/unbound/issues, unbound)
AC_SUBST(UNBOUND_VERSION_MAJOR, [VERSION_MAJOR])
AC_SUBST(UNBOUND_VERSION_MINOR, [VERSION_MINOR])
AC_SUBST(UNBOUND_VERSION_MICRO, [VERSION_MICRO])

LIBUNBOUND_CURRENT=9
LIBUNBOUND_REVISION=4
LIBUNBOUND_AGE=1
# 1.0.0 had 0:12:0
# 1.0.1 had 0:13:0
# 1.0.2 had 0:14:0
# 1.1.0 had 0:15:0
# 1.1.1 had 0:16:0
# 1.2.0 had 0:17:0
# 1.2.1 had 0:18:0
# 1.3.0 had 1:0:0   # ub_cancel and -export-symbols.
# 1.3.1 had 1:1:0
# 1.3.2 had 1:2:0
# 1.3.3 had 1:3:0
# 1.3.4 had 1:4:0
# 1.4.0-snapshots had 1:5:0
# 1.4.0 had 1:5:0 (not 2:0:0)   # ub_result.why_bogus
# 1.4.1 had 2:1:0
# 1.4.2 had 2:2:0
# 1.4.3 had 2:3:0
# 1.4.4 had 2:4:0
# 1.4.5 had 2:5:0
# 1.4.6 had 2:6:0
# 1.4.7 had 2:7:0
# 1.4.8 had 2:8:0
# 1.4.9 had 2:9:0
# 1.4.10 had 2:10:0
# 1.4.11 had 2:11:0
# 1.4.12 had 2:12:0
# 1.4.13 had 2:13:0
# and 1.4.13p1 and 1.4.13.p2
# 1.4.14 had 2:14:0
# 1.4.15 had 3:0:1 # adds ub_version()
# 1.4.16 had 3:1:1
# 1.4.17 had 3:2:1
# 1.4.18 had 3:3:1
# 1.4.19 had 3:4:1
# 1.4.20 had 4:0:2 # adds libunbound.ttl # but shipped 3:5:1
# 1.4.21 had 4:1:2
# 1.4.22 had 4:1:2
# 1.5.0 had 5:3:3 # adds ub_ctx_add_ta_autr
# 1.5.1 had 5:3:3
# 1.5.2 had 5:5:3
# 1.5.3 had 5:6:3
# 1.5.4 had 5:7:3
# 1.5.5 had 5:8:3
# 1.5.6 had 5:9:3
# 1.5.7 had 5:10:3
# 1.5.8 had 6:0:4 # adds ub_ctx_set_stub
# 1.5.9 had 6:1:4
# 1.5.10 had 6:2:4
# 1.6.0 had 6:3:4
# 1.6.1 had 7:0:5 # ub_callback_t typedef renamed to ub_callback_type
# 1.6.2 had 7:1:5
# 1.6.3 had 7:2:5
# 1.6.4 had 7:3:5
# 1.6.5 had 7:4:5
# 1.6.6 had 7:5:5
# 1.6.7 had 7:6:5
# 1.6.8 had 7:7:5
# 1.7.0 had 7:8:5
# 1.7.1 had 7:9:5
# 1.7.2 had 7:10:5
# 1.7.3 had 7:11:5
# 1.8.0 had 8:0:0 # changes the event callback function signature
# 1.8.1 had 8:1:0
# 1.8.2 had 8:2:0
# 1.8.3 had 8:3:0
# 1.9.0 had 9:0:1 # add ub_ctx_set_tls
# 1.9.1 had 9:1:1
# 1.9.2 had 9:2:1
# 1.9.3 had 9:3:1
# 1.9.4 had 9:4:1

#   Current  -- the number of the binary API that we're implementing
#   Revision -- which iteration of the implementation of the binary
#               API are we supplying?
#   Age      -- How many previous binary API versions do we also
#               support?
#
# If we release a new version that does not change the binary API,
# increment Revision.
#
# If we release a new version that changes the binary API, but does
# not break programs compiled against the old binary API, increment
# Current and Age.  Set Revision to 0, since this is the first
# implementation of the new API.
#
# Otherwise, we're changing the binary API and breaking backward
# compatibility with old binaries.  Increment Current.  Set Age to 0,
# since we're backward compatible with no previous APIs.  Set Revision
# to 0 too.
AC_SUBST(LIBUNBOUND_CURRENT)
AC_SUBST(LIBUNBOUND_REVISION)
AC_SUBST(LIBUNBOUND_AGE)


cmdln="`echo $@ | sed -e 's/\\\\/\\\\\\\\/g' | sed -e 's/"/\\\\"/'g`"
AC_DEFINE_UNQUOTED(CONFCMDLINE, ["$cmdln"], [Command line arguments used with configure])

CFLAGS="$CFLAGS"
AC_AIX
if test "$ac_cv_header_minix_config_h" = "yes"; then
	AC_DEFINE(_NETBSD_SOURCE,1, [Enable for compile on Minix])
fi

dnl
dnl By default set prefix to /usr/local
dnl
case "$prefix" in
        NONE)
		prefix="/usr/local"
        ;;
esac
case "$exec_prefix" in
        NONE)
		exec_prefix="$prefix"
        ;;
esac

# are we on MinGW?
if uname -s 2>&1 | grep MINGW32 >/dev/null; then on_mingw="yes"
else 
	if echo $host $target | grep mingw32 >/dev/null; then on_mingw="yes"
	else on_mingw="no"; fi
fi

#
# Determine configuration file
# the eval is to evaluate shell expansion twice
UNBOUND_SBIN_DIR=`eval echo "${sbindir}"`
AC_SUBST(UNBOUND_SBIN_DIR)
UNBOUND_SYSCONF_DIR=`eval echo "${sysconfdir}"`
AC_SUBST(UNBOUND_SYSCONF_DIR)
UNBOUND_LOCALSTATE_DIR=`eval echo "${localstatedir}"`
AC_SUBST(UNBOUND_LOCALSTATE_DIR)
if test $on_mingw = "no"; then
  ub_conf_file=`eval echo "${sysconfdir}/unbound/unbound.conf"`
else
  ub_conf_file="C:\\Program Files\\Unbound\\service.conf"
fi
AC_ARG_WITH([conf_file],
        AC_HELP_STRING([--with-conf-file=path], 
	[Pathname to the Unbound configuration file]),
	[ub_conf_file="$withval"])
AC_SUBST(ub_conf_file)
ACX_ESCAPE_BACKSLASH($ub_conf_file, hdr_config)
AC_DEFINE_UNQUOTED(CONFIGFILE, ["$hdr_config"], [Pathname to the Unbound configuration file])
ub_conf_dir=`AS_DIRNAME(["$ub_conf_file"])`
AC_SUBST(ub_conf_dir)

# Determine run, chroot directory and pidfile locations
AC_ARG_WITH(run-dir, 
    AC_HELP_STRING([--with-run-dir=path], 
    [set default directory to chdir to (by default dir part of cfg file)]), 
    UNBOUND_RUN_DIR="$withval", 
if test $on_mingw = no; then
    UNBOUND_RUN_DIR=`dirname "$ub_conf_file"`
else
    UNBOUND_RUN_DIR=""
fi
)
AC_SUBST(UNBOUND_RUN_DIR)
ACX_ESCAPE_BACKSLASH($UNBOUND_RUN_DIR, hdr_run)
AC_DEFINE_UNQUOTED(RUN_DIR, ["$hdr_run"], [Directory to chdir to])

AC_ARG_WITH(chroot-dir, 
    AC_HELP_STRING([--with-chroot-dir=path], 
    [set default directory to chroot to (by default same as run-dir)]), 
    UNBOUND_CHROOT_DIR="$withval", 
if test $on_mingw = no; then
    UNBOUND_CHROOT_DIR="$UNBOUND_RUN_DIR"
else
    UNBOUND_CHROOT_DIR=""
fi
)
AC_SUBST(UNBOUND_CHROOT_DIR)
ACX_ESCAPE_BACKSLASH($UNBOUND_CHROOT_DIR, hdr_chroot)
AC_DEFINE_UNQUOTED(CHROOT_DIR, ["$hdr_chroot"], [Directory to chroot to])

AC_ARG_WITH(share-dir,
    AC_HELP_STRING([--with-share-dir=path],
    [set default directory with shared data (by default same as share/unbound)]),
    UNBOUND_SHARE_DIR="$withval",
    UNBOUND_SHARE_DIR="$UNBOUND_RUN_DIR")
AC_SUBST(UNBOUND_SHARE_DIR)
AC_DEFINE_UNQUOTED(SHARE_DIR, ["$UNBOUND_SHARE_DIR"], [Shared data])

AC_ARG_WITH(pidfile, 
    AC_HELP_STRING([--with-pidfile=filename], 
    [set default pathname to unbound pidfile (default run-dir/unbound.pid)]), 
    UNBOUND_PIDFILE="$withval", 
if test $on_mingw = no; then
    UNBOUND_PIDFILE="$UNBOUND_RUN_DIR/unbound.pid"
else
    UNBOUND_PIDFILE=""
fi
)
AC_SUBST(UNBOUND_PIDFILE)
ACX_ESCAPE_BACKSLASH($UNBOUND_PIDFILE, hdr_pid)
AC_DEFINE_UNQUOTED(PIDFILE, ["$hdr_pid"], [default pidfile location])

AC_ARG_WITH(rootkey-file, 
    AC_HELP_STRING([--with-rootkey-file=filename], 
    [set default pathname to root key file (default run-dir/root.key). This file is read and written.]), 
    UNBOUND_ROOTKEY_FILE="$withval", 
if test $on_mingw = no; then
    UNBOUND_ROOTKEY_FILE="$UNBOUND_RUN_DIR/root.key"
else
    UNBOUND_ROOTKEY_FILE="C:\\Program Files\\Unbound\\root.key"
fi
)
AC_SUBST(UNBOUND_ROOTKEY_FILE)
ACX_ESCAPE_BACKSLASH($UNBOUND_ROOTKEY_FILE, hdr_rkey)
AC_DEFINE_UNQUOTED(ROOT_ANCHOR_FILE, ["$hdr_rkey"], [default rootkey location])

AC_ARG_WITH(rootcert-file, 
    AC_HELP_STRING([--with-rootcert-file=filename], 
    [set default pathname to root update certificate file (default run-dir/icannbundle.pem).  This file need not exist if you are content with the builtin.]), 
    UNBOUND_ROOTCERT_FILE="$withval", 
if test $on_mingw = no; then
    UNBOUND_ROOTCERT_FILE="$UNBOUND_RUN_DIR/icannbundle.pem"
else
    UNBOUND_ROOTCERT_FILE="C:\\Program Files\\Unbound\\icannbundle.pem"
fi
)
AC_SUBST(UNBOUND_ROOTCERT_FILE)
ACX_ESCAPE_BACKSLASH($UNBOUND_ROOTCERT_FILE, hdr_rpem)
AC_DEFINE_UNQUOTED(ROOT_CERT_FILE, ["$hdr_rpem"], [default rootcert location])

AC_ARG_WITH(username, 
    AC_HELP_STRING([--with-username=user], 
    [set default user that unbound changes to (default user is unbound)]), 
    UNBOUND_USERNAME="$withval", 
    UNBOUND_USERNAME="unbound")
AC_SUBST(UNBOUND_USERNAME)
AC_DEFINE_UNQUOTED(UB_USERNAME, ["$UNBOUND_USERNAME"], [default username])

AC_DEFINE(WINVER, 0x0502, [the version of the windows API enabled])
ACX_RSRC_VERSION(wnvs)
AC_DEFINE_UNQUOTED(RSRC_PACKAGE_VERSION, [$wnvs], [version number for resource files])

# Checks for typedefs, structures, and compiler characteristics.
AC_C_CONST
AC_LANG_C
# allow user to override the -g -O2 flags.
default_cflags=no
if test "x$CFLAGS" = "x" ; then
ACX_CHECK_COMPILER_FLAG(g, [CFLAGS="$CFLAGS -g"])
ACX_CHECK_COMPILER_FLAG(O2, [CFLAGS="$CFLAGS -O2"])
default_cflags=yes
fi
AC_PROG_CC
ACX_DEPFLAG
ACX_DETERMINE_EXT_FLAGS_UNBOUND

# debug mode flags warnings
AC_ARG_ENABLE(checking, AC_HELP_STRING([--enable-checking], [Enable warnings, asserts, makefile-dependencies]))
AC_ARG_ENABLE(debug, AC_HELP_STRING([--enable-debug], [same as enable-checking]))
if test "$enable_debug" = "yes"; then debug_enabled="$enable_debug"; 
else debug_enabled="$enable_checking"; fi
AC_SUBST(debug_enabled)
case "$debug_enabled" in
        yes)
		ACX_CHECK_COMPILER_FLAG(W, [CFLAGS="$CFLAGS -W"])
		ACX_CHECK_COMPILER_FLAG(Wall, [CFLAGS="$CFLAGS -Wall"])
		ACX_CHECK_COMPILER_FLAG(Wextra, [CFLAGS="$CFLAGS -Wextra"])
		ACX_CHECK_COMPILER_FLAG(Wdeclaration-after-statement, [CFLAGS="$CFLAGS -Wdeclaration-after-statement"])
		AC_DEFINE([UNBOUND_DEBUG], [], [define this to enable debug checks.])
		;;
	no|*)
		# nothing to do.
		;;
esac
if test "$default_cflags" = "yes"; then
	# only when CFLAGS was "" at the start, if the users wants to
	# override we shouldn't add default cflags, because they wouldn't
	# be able to turn off these options and set the CFLAGS wanted.
	ACX_CHECK_FLTO
	ACX_CHECK_PIE
	ACX_CHECK_RELRO_NOW
fi

AC_C_INLINE
ACX_CHECK_FORMAT_ATTRIBUTE
ACX_CHECK_UNUSED_ATTRIBUTE

AC_DEFUN([CHECK_WEAK_ATTRIBUTE],
[AC_REQUIRE([AC_PROG_CC])
AC_MSG_CHECKING(whether the C compiler (${CC-cc}) accepts the "weak" attribute)
AC_CACHE_VAL(ac_cv_c_weak_attribute,
[ac_cv_c_weak_attribute=no
AC_TRY_COMPILE(
[ #include <stdio.h>
__attribute__((weak)) void f(int x) { printf("%d", x); }
], [
   f(1);
],
[ac_cv_c_weak_attribute="yes"],
[ac_cv_c_weak_attribute="no"])
])

AC_MSG_RESULT($ac_cv_c_weak_attribute)
if test $ac_cv_c_weak_attribute = yes; then
  AC_DEFINE(HAVE_ATTR_WEAK, 1, [Whether the C compiler accepts the "weak" attribute])
  AC_DEFINE(ATTR_WEAK, [__attribute__((weak))], [apply the weak attribute to a symbol])
fi
])dnl End of CHECK_WEAK_ATTRIBUTE

CHECK_WEAK_ATTRIBUTE

AC_DEFUN([CHECK_NORETURN_ATTRIBUTE],
[AC_REQUIRE([AC_PROG_CC])
AC_MSG_CHECKING(whether the C compiler (${CC-cc}) accepts the "noreturn" attribute)
AC_CACHE_VAL(ac_cv_c_noreturn_attribute,
[ac_cv_c_noreturn_attribute=no
AC_TRY_COMPILE(
[ #include <stdio.h>
__attribute__((noreturn)) void f(int x) { printf("%d", x); }
], [
   f(1);
],
[ac_cv_c_noreturn_attribute="yes"],
[ac_cv_c_noreturn_attribute="no"])
])

AC_MSG_RESULT($ac_cv_c_noreturn_attribute)
if test $ac_cv_c_noreturn_attribute = yes; then
  AC_DEFINE(HAVE_ATTR_NORETURN, 1, [Whether the C compiler accepts the "noreturn" attribute])
  AC_DEFINE(ATTR_NORETURN, [__attribute__((__noreturn__))], [apply the noreturn attribute to a function that exits the program])
fi
])dnl End of CHECK_NORETURN_ATTRIBUTE

CHECK_NORETURN_ATTRIBUTE

if test "$srcdir" != "."; then
	CPPFLAGS="$CPPFLAGS -I$srcdir"
fi

AC_DEFUN([ACX_YYLEX_DESTROY], [
	AC_MSG_CHECKING([for yylex_destroy])
	if echo %% | $LEX -t 2>&1 | grep yylex_destroy >/dev/null 2>&1; then
		AC_DEFINE(LEX_HAS_YYLEX_DESTROY, 1, [if lex has yylex_destroy])
		AC_MSG_RESULT(yes)
	else AC_MSG_RESULT(no);
		LEX=":"
	fi
])

AC_DEFUN([ACX_YYLEX_OPTION], [
	AC_MSG_CHECKING([for lex %option])
	if cat <<EOF | $LEX -t 2>&1 | grep yy_delete_buffer >/dev/null 2>&1; then
%option nounput
%%
EOF
		AC_MSG_RESULT(yes)
	else AC_MSG_RESULT(no);
		LEX=":"
	fi
])

AC_PROG_LEX
if test "$LEX" != "" -a "$LEX" != ":"; then
ACX_YYLEX_DESTROY
fi
if test "$LEX" != "" -a "$LEX" != ":"; then
ACX_YYLEX_OPTION
fi
AC_PROG_YACC
AC_CHECK_PROG(doxygen, doxygen, doxygen)
AC_CHECK_TOOL(STRIP, strip)
ACX_LIBTOOL_C_ONLY

PKG_PROG_PKG_CONFIG

# Checks for header files.
AC_CHECK_HEADERS([stdarg.h stdbool.h netinet/in.h netinet/tcp.h sys/param.h sys/socket.h sys/un.h sys/uio.h sys/resource.h arpa/inet.h syslog.h netdb.h sys/wait.h pwd.h glob.h grp.h login_cap.h winsock2.h ws2tcpip.h endian.h sys/endian.h libkern/OSByteOrder.h sys/ipc.h sys/shm.h],,, [AC_INCLUDES_DEFAULT])

# check for types.  
# Using own tests for int64* because autoconf builtin only give 32bit.
AC_CHECK_TYPE(int8_t, signed char)
AC_CHECK_TYPE(int16_t, short)
AC_CHECK_TYPE(int32_t, int)
AC_CHECK_TYPE(int64_t, long long)
AC_CHECK_TYPE(uint8_t, unsigned char)
AC_CHECK_TYPE(uint16_t, unsigned short)
AC_CHECK_TYPE(uint32_t, unsigned int)
AC_CHECK_TYPE(uint64_t, unsigned long long)
AC_TYPE_SIZE_T
AC_CHECK_TYPE(ssize_t, int)
AC_TYPE_UID_T
AC_TYPE_PID_T
AC_TYPE_OFF_T
ACX_TYPE_U_CHAR
ACX_TYPE_RLIM_T
ACX_TYPE_SOCKLEN_T
ACX_TYPE_IN_ADDR_T
ACX_TYPE_IN_PORT_T
ACX_CHECK_MEMCMP_SIGNED

AC_CHECK_SIZEOF(time_t,,[
AC_INCLUDES_DEFAULT
#ifdef TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# ifdef HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif
])

# add option to disable the evil rpath
ACX_ARG_RPATH
AC_SUBST(RUNTIME_PATH)

# check to see if libraries are needed for these functions.
AC_SEARCH_LIBS([inet_pton], [nsl])
AC_SEARCH_LIBS([socket], [socket])

# check wether strptime also works
AC_DEFUN([AC_CHECK_STRPTIME_WORKS],
[AC_REQUIRE([AC_PROG_CC])
AC_MSG_CHECKING(whether strptime works)
if test c${cross_compiling} = cno; then
AC_RUN_IFELSE([AC_LANG_SOURCE([[
#define _XOPEN_SOURCE 600
#include <time.h>
int main(void) { struct tm tm; char *res;
res = strptime("2010-07-15T00:00:00+00:00", "%t%Y%t-%t%m%t-%t%d%tT%t%H%t:%t%M%t:%t%S%t", &tm);
if (!res) return 2;
res = strptime("20070207111842", "%Y%m%d%H%M%S", &tm);
if (!res) return 1; return 0; }
]])] , [eval "ac_cv_c_strptime_works=yes"], [eval "ac_cv_c_strptime_works=no"])
else
eval "ac_cv_c_strptime_works=maybe"
fi
AC_MSG_RESULT($ac_cv_c_strptime_works)
if test $ac_cv_c_strptime_works = no; then
AC_LIBOBJ(strptime)
else
AC_DEFINE_UNQUOTED([STRPTIME_WORKS], 1, [use default strptime.])
fi
])dnl

# check some functions of the OS before linking libs (while still runnable).
AC_FUNC_CHOWN
AC_FUNC_FORK
AC_TYPE_SIGNAL
AC_FUNC_FSEEKO
ACX_SYS_LARGEFILE
ACX_CHECK_NONBLOCKING_BROKEN
ACX_MKDIR_ONE_ARG
AC_CHECK_FUNCS([strptime],[AC_CHECK_STRPTIME_WORKS],[AC_LIBOBJ([strptime])])

# check if we can use SO_REUSEPORT
if echo "$host" | grep -i -e linux -e dragonfly >/dev/null; then
	AC_DEFINE(REUSEPORT_DEFAULT, 1, [if REUSEPORT is enabled by default])
else
	AC_DEFINE(REUSEPORT_DEFAULT, 0, [if REUSEPORT is enabled by default])
fi

# Include systemd.m4 - begin
sinclude(systemd.m4)
# Include systemd.m4 - end

# set memory allocation checking if requested
AC_ARG_ENABLE(alloc-checks, AC_HELP_STRING([--enable-alloc-checks],
	[ enable to memory allocation statistics, for debug purposes ]), 
	, )
AC_ARG_ENABLE(alloc-lite, AC_HELP_STRING([--enable-alloc-lite],
	[ enable for lightweight alloc assertions, for debug purposes ]), 
	, )
AC_ARG_ENABLE(alloc-nonregional, AC_HELP_STRING([--enable-alloc-nonregional],
	[ enable nonregional allocs, slow but exposes regional allocations to other memory purifiers, for debug purposes ]), 
	, )
if test x_$enable_alloc_nonregional = x_yes; then
	AC_DEFINE(UNBOUND_ALLOC_NONREGIONAL, 1, [use malloc not regions, for debug use])
fi
if test x_$enable_alloc_checks = x_yes; then
	AC_DEFINE(UNBOUND_ALLOC_STATS, 1, [use statistics for allocs and frees, for debug use])
else
	if test x_$enable_alloc_lite = x_yes; then
		AC_DEFINE(UNBOUND_ALLOC_LITE, 1, [use to enable lightweight alloc assertions, for debug use])
	else
		ACX_FUNC_MALLOC([unbound])
	fi
fi

# check windows threads (we use them, not pthreads, on windows).
if test "$on_mingw" = "yes"; then
# check windows threads
	AC_CHECK_HEADERS([windows.h],,, [AC_INCLUDES_DEFAULT])
	AC_MSG_CHECKING([for CreateThread])
	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
#ifdef HAVE_WINDOWS_H
#include <windows.h>
#endif
], [
	HANDLE t = CreateThread(NULL, 0, NULL, NULL, 0, NULL);
])],
	AC_MSG_RESULT(yes)
	AC_DEFINE(HAVE_WINDOWS_THREADS, 1, [Using Windows threads])
,	
	AC_MSG_RESULT(no)
)

else
# not on mingw, check thread libraries.

# check for thread library.
# check this first, so that the pthread lib does not get linked in via
# libssl or libpython, and thus distorts the tests, and we end up using
# the non-threadsafe C libraries.
AC_ARG_WITH(pthreads, AC_HELP_STRING([--with-pthreads], 
 [use pthreads library, or --without-pthreads to disable threading support.]), 
 [ ],[ withval="yes" ])
ub_have_pthreads=no
if test x_$withval != x_no; then
	AX_PTHREAD([
		AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.])
		if test -n "$PTHREAD_LIBS"; then
		  LIBS="$PTHREAD_LIBS $LIBS"
		fi
		CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
		CC="$PTHREAD_CC"
		ub_have_pthreads=yes
		AC_CHECK_TYPES([pthread_spinlock_t, pthread_rwlock_t],,,[#include <pthread.h>])

		if echo "$CFLAGS" | $GREP -e "-pthread" >/dev/null; then
		AC_MSG_CHECKING([if -pthread unused during linking])
		# catch clang warning 'argument unused during compilation'
		AC_LANG_CONFTEST([AC_LANG_SOURCE(AC_INCLUDES_DEFAULT
[[
int main(void) {return 0;}
]])])
		pthread_unused="yes"
		# first compile
		echo "$CC $CFLAGS -c conftest.c -o conftest.o" >&AS_MESSAGE_LOG_FD
		$CC $CFLAGS -c conftest.c -o conftest.o 2>&AS_MESSAGE_LOG_FD >&AS_MESSAGE_LOG_FD
		if test $? = 0; then 
			# then link
			echo "$CC $CFLAGS -Werror $LDFLAGS $LIBS -o conftest contest.o" >&AS_MESSAGE_LOG_FD
			$CC $CFLAGS -Werror $LDFLAGS $LIBS -o conftest conftest.o 2>&AS_MESSAGE_LOG_FD >&AS_MESSAGE_LOG_FD
			if test $? -ne 0; then
				AC_MSG_RESULT(yes)
				CFLAGS=`echo "$CFLAGS" | sed -e 's/-pthread//'`
				PTHREAD_CFLAGS_ONLY="-pthread"
				AC_SUBST(PTHREAD_CFLAGS_ONLY)
			else
				AC_MSG_RESULT(no)
			fi
		else
			AC_MSG_RESULT(no)
		fi # endif cc successful
		rm -f conftest conftest.c conftest.o
		fi # endif -pthread in CFLAGS

		])
fi

# check solaris thread library 
AC_ARG_WITH(solaris-threads, AC_HELP_STRING([--with-solaris-threads], 
	[use solaris native thread library.]), [ ],[ withval="no" ])
ub_have_sol_threads=no
if test x_$withval != x_no; then
	if test x_$ub_have_pthreads != x_no; then
	    AC_WARN([Have pthreads already, ignoring --with-solaris-threads])
	else
	AC_SEARCH_LIBS(thr_create, [thread],
	[
    		AC_DEFINE(HAVE_SOLARIS_THREADS, 1, [Using Solaris threads])

		ACX_CHECK_COMPILER_FLAG(mt, [CFLAGS="$CFLAGS -mt"],
			[CFLAGS="$CFLAGS -D_REENTRANT"])
		ub_have_sol_threads=yes
	] , [ 
		AC_ERROR([no solaris threads found.]) 
	])
	fi
fi

fi # end of non-mingw check of thread libraries

# Check for PyUnbound
AC_ARG_WITH(pyunbound,
   AC_HELP_STRING([--with-pyunbound],
   [build PyUnbound, or --without-pyunbound to skip it. (default=no)]),
   [], [ withval="no" ])

ub_test_python=no
ub_with_pyunbound=no
if test x_$withval != x_no; then
   ub_with_pyunbound=yes
   ub_test_python=yes
fi

# Check for Python module
AC_ARG_WITH(pythonmodule,
   AC_HELP_STRING([--with-pythonmodule],
   [build Python module, or --without-pythonmodule to disable script engine. (default=no)]),
   [], [ withval="no" ])

ub_with_pythonmod=no
if test x_$withval != x_no; then
   ub_with_pythonmod=yes
   ub_test_python=yes
fi

# Check for Python & SWIG only on PyUnbound or PyModule
if test x_$ub_test_python != x_no; then

   # Check for Python
   ub_have_python=no
   ac_save_LIBS="$LIBS" dnl otherwise AC_PYTHON_DEVEL thrashes $LIBS
   AC_PYTHON_DEVEL
   if test ! -z "$PYTHON_VERSION"; then
	if test `$PYTHON -c "print('$PYTHON_VERSION' >= '2.4.0')"` = "False"; then
		AC_ERROR([Python version >= 2.4.0 is required])
	fi

      [PY_MAJOR_VERSION="`$PYTHON -c \"import sys; print(sys.version_info[0])\"`"]
      AC_SUBST(PY_MAJOR_VERSION)
      # Have Python
      AC_DEFINE(HAVE_PYTHON,1,[Define if you have Python libraries and header files.])
      if test -n "$LIBS"; then
        LIBS="$PYTHON_LDFLAGS $LIBS"
      else
        LIBS="$PYTHON_LDFLAGS"
      fi
      if test -n "$CPPFLAGS"; then
        CPPFLAGS="$CPPFLAGS $PYTHON_CPPFLAGS"
      else
        CPPFLAGS="$PYTHON_CPPFLAGS"
      fi
      ub_have_python=yes
      PKG_CHECK_EXISTS(["python${PY_MAJOR_VERSION}"],
                       [PC_PY_DEPENDENCY="python${PY_MAJOR_VERSION}"],
                       [PC_PY_DEPENDENCY="python"])
      AC_SUBST(PC_PY_DEPENDENCY)

      # Check for SWIG
      ub_have_swig=no
      AC_ARG_ENABLE(swig-version-check, AC_HELP_STRING([--disable-swig-version-check], [Disable swig version check to build python modules with older swig even though that is unreliable]))
      if test "$enable_swig_version_check" = "yes"; then
      	AC_PROG_SWIG(2.0.1)
      else
      	AC_PROG_SWIG
      fi
      AC_MSG_CHECKING(SWIG)
      if test ! -x "$SWIG"; then
         AC_ERROR([failed to find swig tool, install it, or do not build Python module and PyUnbound])
      else
         AC_DEFINE(HAVE_SWIG, 1, [Define if you have Swig libraries and header files.])
         AC_SUBST(swig, "$SWIG")
         AC_MSG_RESULT(present)

         # If have Python & SWIG
         # Declare PythonMod
         if test x_$ub_with_pythonmod != x_no; then
            AC_DEFINE(WITH_PYTHONMODULE, 1, [Define if you want Python module.])
            WITH_PYTHONMODULE=yes
            AC_SUBST(WITH_PYTHONMODULE)
	    PYTHONMOD_OBJ="pythonmod.lo pythonmod_utils.lo"
	    AC_SUBST(PYTHONMOD_OBJ)
	    PYTHONMOD_HEADER='$(srcdir)/pythonmod/pythonmod.h'
	    AC_SUBST(PYTHONMOD_HEADER)
	    PYTHONMOD_INSTALL=pythonmod-install
	    AC_SUBST(PYTHONMOD_INSTALL)
	    PYTHONMOD_UNINSTALL=pythonmod-uninstall
	    AC_SUBST(PYTHONMOD_UNINSTALL)
         fi

         # Declare PyUnbound
         if test x_$ub_with_pyunbound != x_no; then
            AC_DEFINE(WITH_PYUNBOUND, 1, [Define if you want PyUnbound.])
            WITH_PYUNBOUND=yes
            AC_SUBST(WITH_PYUNBOUND)
	    PYUNBOUND_OBJ="libunbound_wrap.lo"
	    AC_SUBST(PYUNBOUND_OBJ)
	    PYUNBOUND_TARGET="_unbound.la"
	    AC_SUBST(PYUNBOUND_TARGET)
	    PYUNBOUND_INSTALL=pyunbound-install
	    AC_SUBST(PYUNBOUND_INSTALL)
	    PYUNBOUND_UNINSTALL=pyunbound-uninstall
	    AC_SUBST(PYUNBOUND_UNINSTALL)
         fi
      fi
   else
      AC_MSG_RESULT([*** Python libraries not found, won't build PythonMod or PyUnbound ***])
      ub_with_pyunbound=no
      ub_with_pythonmod=no
   fi
fi

if test "`uname`" = "NetBSD"; then
	NETBSD_LINTFLAGS='"-D__RENAME(x)=" -D_NETINET_IN_H_'
	AC_SUBST(NETBSD_LINTFLAGS)
fi
CONFIG_DATE=`date +%Y%m%d`
AC_SUBST(CONFIG_DATE)

# Checks for libraries.

# libnss
USE_NSS="no"
AC_ARG_WITH([nss], AC_HELP_STRING([--with-nss=path],
	[use libnss instead of openssl, installed at path.]),
	[
	USE_NSS="yes"
	AC_DEFINE(HAVE_NSS, 1, [Use libnss for crypto])
	if test "$withval" != "" -a "$withval" != "yes"; then
		CPPFLAGS="$CPPFLAGS -I$withval/include/nss3"
		LDFLAGS="$LDFLAGS -L$withval/lib"
		ACX_RUNTIME_PATH_ADD([$withval/lib])
		CPPFLAGS="-I$withval/include/nspr4 $CPPFLAGS"
	else
		CPPFLAGS="$CPPFLAGS -I/usr/include/nss3"
		CPPFLAGS="-I/usr/include/nspr4 $CPPFLAGS"
	fi
        LIBS="$LIBS -lnss3 -lnspr4"
	SSLLIB=""
	]
)

# libnettle
USE_NETTLE="no"
AC_ARG_WITH([nettle], AC_HELP_STRING([--with-nettle=path],
	[use libnettle as crypto library, installed at path.]),
	[
	USE_NETTLE="yes"
	AC_DEFINE(HAVE_NETTLE, 1, [Use libnettle for crypto])
	AC_CHECK_HEADERS([nettle/dsa-compat.h],,, [AC_INCLUDES_DEFAULT])
	if test "$withval" != "" -a "$withval" != "yes"; then
		CPPFLAGS="$CPPFLAGS -I$withval/include/nettle"
		LDFLAGS="$LDFLAGS -L$withval/lib"
		ACX_RUNTIME_PATH_ADD([$withval/lib])
	else
		CPPFLAGS="$CPPFLAGS -I/usr/include/nettle"
	fi
        LIBS="$LIBS -lhogweed -lnettle -lgmp"
	SSLLIB=""
	]
)

# openssl
if test $USE_NSS = "no" -a $USE_NETTLE = "no"; then
ACX_WITH_SSL
ACX_LIB_SSL
SSLLIB="-lssl"

# check if -lcrypt32 is needed because CAPIENG needs that. (on windows)
BAKLIBS="$LIBS"
LIBS="-lssl $LIBS"
AC_MSG_CHECKING([if libssl needs -lcrypt32])
AC_TRY_LINK_FUNC([HMAC_Update], [
	AC_MSG_RESULT([no])
	LIBS="$BAKLIBS"
], [
	AC_MSG_RESULT([yes])
	LIBS="$BAKLIBS"
	LIBS="$LIBS -lcrypt32"
])

AC_MSG_CHECKING([for LibreSSL])
if grep VERSION_TEXT $ssldir/include/openssl/opensslv.h | grep "LibreSSL" >/dev/null; then
	AC_MSG_RESULT([yes])
	AC_DEFINE([HAVE_LIBRESSL], [1], [Define if we have LibreSSL])
	# libressl provides these compat functions, but they may also be
	# declared by the OS in libc.  See if they have been declared.
	AC_CHECK_DECLS([strlcpy,strlcat,arc4random,arc4random_uniform,reallocarray])
else
	AC_MSG_RESULT([no])
fi
AC_CHECK_HEADERS([openssl/conf.h openssl/engine.h openssl/bn.h openssl/dh.h openssl/dsa.h openssl/rsa.h],,, [AC_INCLUDES_DEFAULT])
AC_CHECK_FUNCS([OPENSSL_config EVP_sha1 EVP_sha256 EVP_sha512 FIPS_mode EVP_MD_CTX_new OpenSSL_add_all_digests OPENSSL_init_crypto EVP_cleanup ERR_load_crypto_strings CRYPTO_cleanup_all_ex_data ERR_free_strings RAND_cleanup DSA_SIG_set0 EVP_dss1 EVP_DigestVerify SSL_CTX_set_tlsext_ticket_key_cb EVP_aes_256_cbc EVP_EncryptInit_ex HMAC_Init_ex CRYPTO_THREADID_set_callback])

# these check_funcs need -lssl
BAKLIBS="$LIBS"
LIBS="-lssl $LIBS"
AC_CHECK_FUNCS([OPENSSL_init_ssl SSL_CTX_set_security_level SSL_set1_host SSL_get0_peername X509_VERIFY_PARAM_set1_host SSL_CTX_set_ciphersuites])
LIBS="$BAKLIBS"

AC_CHECK_DECLS([SSL_COMP_get_compression_methods,sk_SSL_COMP_pop_free,SSL_CTX_set_ecdh_auto], [], [], [
AC_INCLUDES_DEFAULT
#ifdef HAVE_OPENSSL_ERR_H
#include <openssl/err.h>
#endif

#ifdef HAVE_OPENSSL_RAND_H
#include <openssl/rand.h>
#endif

#ifdef HAVE_OPENSSL_CONF_H
#include <openssl/conf.h>
#endif

#ifdef HAVE_OPENSSL_ENGINE_H
#include <openssl/engine.h>
#endif
#include <openssl/ssl.h>
#include <openssl/evp.h>
])
fi
AC_SUBST(SSLLIB)


AC_ARG_ENABLE(sha1, AC_HELP_STRING([--disable-sha1], [Disable SHA1 RRSIG support, does not disable nsec3 support]))
case "$enable_sha1" in
	no)
	;;
	yes|*)
	AC_DEFINE([USE_SHA1], [1], [Define this to enable SHA1 support.])
	;;
esac


AC_ARG_ENABLE(sha2, AC_HELP_STRING([--disable-sha2], [Disable SHA256 and SHA512 RRSIG support]))
case "$enable_sha2" in
	no)
	;;
	yes|*)
	AC_DEFINE([USE_SHA2], [1], [Define this to enable SHA256 and SHA512 support.])
	;;
esac

AC_ARG_ENABLE(subnet, AC_HELP_STRING([--enable-subnet], [Enable client subnet]))
case "$enable_subnet" in
	yes)
	AC_DEFINE([CLIENT_SUBNET], [1], [Define this to enable client subnet option.])
	SUBNET_OBJ="edns-subnet.lo subnetmod.lo addrtree.lo subnet-whitelist.lo"
	AC_SUBST(SUBNET_OBJ)
	SUBNET_HEADER='$(srcdir)/edns-subnet/subnetmod.h $(srcdir)/edns-subnet/edns-subnet.h $(srcdir)/edns-subnet/subnet-whitelist.h $(srcdir)/edns-subnet/addrtree.h'
	AC_SUBST(SUBNET_HEADER)
	;;
	no|*)
	;;
esac

# check wether gost also works
AC_DEFUN([AC_CHECK_GOST_WORKS],
[AC_REQUIRE([AC_PROG_CC])
AC_MSG_CHECKING([if GOST works])
if test c${cross_compiling} = cno; then
BAKCFLAGS="$CFLAGS"
if test -n "$ssldir"; then
	CFLAGS="$CFLAGS -Wl,-rpath,$ssldir/lib"
fi
AC_RUN_IFELSE([AC_LANG_SOURCE([[
#include <string.h>
#include <openssl/ssl.h>
#include <openssl/evp.h>
#include <openssl/engine.h>
#include <openssl/conf.h>
/* routine to load gost (from sldns) */
int load_gost_id(void)
{
	static int gost_id = 0;
	const EVP_PKEY_ASN1_METHOD* meth;
	ENGINE* e;

	if(gost_id) return gost_id;

	/* see if configuration loaded gost implementation from other engine*/
	meth = EVP_PKEY_asn1_find_str(NULL, "gost2001", -1);
	if(meth) {
		EVP_PKEY_asn1_get0_info(&gost_id, NULL, NULL, NULL, NULL, meth);
		return gost_id;
	}

	/* see if engine can be loaded already */
	e = ENGINE_by_id("gost");
	if(!e) {
		/* load it ourself, in case statically linked */
		ENGINE_load_builtin_engines();
		ENGINE_load_dynamic();
		e = ENGINE_by_id("gost");
	}
	if(!e) {
		/* no gost engine in openssl */
		return 0;
	}
	if(!ENGINE_set_default(e, ENGINE_METHOD_ALL)) {
		ENGINE_finish(e);
		ENGINE_free(e);
		return 0;
	}

	meth = EVP_PKEY_asn1_find_str(&e, "gost2001", -1);
	if(!meth) {
		/* algo not found */
		ENGINE_finish(e);
		ENGINE_free(e);
		return 0;
	}
	EVP_PKEY_asn1_get0_info(&gost_id, NULL, NULL, NULL, NULL, meth);
	return gost_id;
}
int main(void) { 
	EVP_MD_CTX* ctx;
	const EVP_MD* md;
	unsigned char digest[64]; /* its a 256-bit digest, so uses 32 bytes */
	const char* str = "Hello world";
	const unsigned char check[] = {
		0x40 , 0xed , 0xf8 , 0x56 , 0x5a , 0xc5 , 0x36 , 0xe1 ,
		0x33 , 0x7c , 0x7e , 0x87 , 0x62 , 0x1c , 0x42 , 0xe0 ,
		0x17 , 0x1b , 0x5e , 0xce , 0xa8 , 0x46 , 0x65 , 0x4d ,
		0x8d , 0x3e , 0x22 , 0x9b , 0xe1 , 0x30 , 0x19 , 0x9d
	};
	OPENSSL_config(NULL);
	(void)load_gost_id();
	md = EVP_get_digestbyname("md_gost94");
	if(!md) return 1;
	memset(digest, 0, sizeof(digest));
	ctx = EVP_MD_CTX_create();
	if(!ctx) return 2;
	if(!EVP_DigestInit_ex(ctx, md, NULL)) return 3;
	if(!EVP_DigestUpdate(ctx, str, 10)) return 4;
	if(!EVP_DigestFinal_ex(ctx, digest, NULL)) return 5;
	/* uncomment to see the hash calculated.
		{int i;
		for(i=0; i<32; i++)
			printf(" %2.2x", (int)digest[i]);
		printf("\n");}
	*/
	if(memcmp(digest, check, sizeof(check)) != 0)
		return 6;
	return 0;
}
]])] , [eval "ac_cv_c_gost_works=yes"], [eval "ac_cv_c_gost_works=no"])
CFLAGS="$BAKCFLAGS"
else
eval "ac_cv_c_gost_works=maybe"
fi
AC_MSG_RESULT($ac_cv_c_gost_works)
])dnl

AC_ARG_ENABLE(gost, AC_HELP_STRING([--disable-gost], [Disable GOST support]))
use_gost="no"
if test $USE_NSS = "no" -a $USE_NETTLE = "no"; then
case "$enable_gost" in
	no)
	;;
	*)
	AC_CHECK_FUNC(EVP_PKEY_set_type_str, [:],[AC_MSG_ERROR([OpenSSL 1.0.0 is needed for GOST support])])
	AC_CHECK_FUNC(EC_KEY_new, [], [AC_MSG_ERROR([OpenSSL does not support ECC, needed for GOST support])])
	AC_CHECK_GOST_WORKS
	if test "$ac_cv_c_gost_works" != no; then
		use_gost="yes"
		AC_DEFINE([USE_GOST], [1], [Define this to enable GOST support.])
	fi
	;;
esac
fi dnl !USE_NSS && !USE_NETTLE

AC_ARG_ENABLE(ecdsa, AC_HELP_STRING([--disable-ecdsa], [Disable ECDSA support]))
use_ecdsa="no"
case "$enable_ecdsa" in
    no)
      ;;
    *)
      if test $USE_NSS = "no" -a $USE_NETTLE = "no"; then
	      AC_CHECK_FUNC(ECDSA_sign, [], [AC_MSG_ERROR([OpenSSL does not support ECDSA: please upgrade or rerun with --disable-ecdsa])])
	      AC_CHECK_FUNC(SHA384_Init, [], [AC_MSG_ERROR([OpenSSL does not support SHA384: please upgrade or rerun with --disable-ecdsa])])
	      AC_CHECK_DECLS([NID_X9_62_prime256v1, NID_secp384r1], [], [AC_MSG_ERROR([OpenSSL does not support the ECDSA curves: please upgrade or rerun with --disable-ecdsa])], [AC_INCLUDES_DEFAULT
#include <openssl/evp.h>
	      ])
	      # see if OPENSSL 1.0.0 or later (has EVP MD and Verify independency)
	      AC_MSG_CHECKING([if openssl supports SHA2 and ECDSA with EVP])
	      if grep OPENSSL_VERSION_TEXT $ssldir/include/openssl/opensslv.h | grep "OpenSSL" >/dev/null; then
		if grep OPENSSL_VERSION_NUMBER $ssldir/include/openssl/opensslv.h | grep 0x0 >/dev/null; then
		  AC_MSG_RESULT([no])
		  AC_DEFINE_UNQUOTED([USE_ECDSA_EVP_WORKAROUND], [1], [Define this to enable an EVP workaround for older openssl])
		else
		  AC_MSG_RESULT([yes])
		fi
	      else
		# not OpenSSL, thus likely LibreSSL, which supports it
		AC_MSG_RESULT([yes])
	      fi
      fi
      # we now know we have ECDSA and the required curves.
      AC_DEFINE_UNQUOTED([USE_ECDSA], [1], [Define this to enable ECDSA support.])
      use_ecdsa="yes"
      ;;
esac

AC_ARG_ENABLE(dsa, AC_HELP_STRING([--disable-dsa], [Disable DSA support]))
use_dsa="no"
case "$enable_dsa" in
    no)
      ;;
    *)
      # detect if DSA is supported, and turn it off if not.
      if test $USE_NSS = "no" -a $USE_NETTLE = "no"; then
      AC_CHECK_FUNC(DSA_SIG_new, [
      AC_CHECK_TYPE(DSA_SIG*, [
      AC_DEFINE_UNQUOTED([USE_DSA], [1], [Define this to enable DSA support.])
      ], [if test "x$enable_dsa" = "xyes"; then AC_MSG_ERROR([OpenSSL does not support DSA and you used --enable-dsa.])
               fi ], [
AC_INCLUDES_DEFAULT
#ifdef HAVE_OPENSSL_ERR_H
#include <openssl/err.h>
#endif

#ifdef HAVE_OPENSSL_RAND_H
#include <openssl/rand.h>
#endif

#ifdef HAVE_OPENSSL_CONF_H
#include <openssl/conf.h>
#endif

#ifdef HAVE_OPENSSL_ENGINE_H
#include <openssl/engine.h>
#endif
      ])
      ], [if test "x$enable_dsa" = "xyes"; then AC_MSG_ERROR([OpenSSL does not support DSA and you used --enable-dsa.])
               fi ])
      else
      AC_DEFINE_UNQUOTED([USE_DSA], [1], [Define this to enable DSA support.])
      fi
      ;;
esac

AC_ARG_ENABLE(ed25519, AC_HELP_STRING([--disable-ed25519], [Disable ED25519 support]))
use_ed25519="no"
case "$enable_ed25519" in
    no)
      ;;
    *)
      if test $USE_NSS = "no" -a $USE_NETTLE = "no"; then
	      AC_CHECK_DECLS([NID_ED25519], [
      		use_ed25519="yes"
	      ], [ if test "x$enable_ed25519" = "xyes"; then AC_MSG_ERROR([OpenSSL does not support ED25519 and you used --enable-ed25519.])
	      	fi ], [AC_INCLUDES_DEFAULT
#include <openssl/evp.h>
	      ])
      fi
      if test $USE_NETTLE = "yes"; then
		AC_CHECK_HEADERS([nettle/eddsa.h], use_ed25519="yes",, [AC_INCLUDES_DEFAULT])
      fi
      if test $use_ed25519 = "yes"; then
      		AC_DEFINE_UNQUOTED([USE_ED25519], [1], [Define this to enable ED25519 support.])
      fi
      ;;
esac

AC_ARG_ENABLE(ed448, AC_HELP_STRING([--disable-ed448], [Disable ED448 support]))
use_ed448="no"
case "$enable_ed448" in
    no)
      ;;
    *)
      if test $USE_NSS = "no" -a $USE_NETTLE = "no"; then
	      AC_CHECK_DECLS([NID_ED448], [
      		use_ed448="yes"
	      ], [ if test "x$enable_ed448" = "xyes"; then AC_MSG_ERROR([OpenSSL does not support ED448 and you used --enable-ed448.])
	      	fi ], [AC_INCLUDES_DEFAULT
#include <openssl/evp.h>
	      ])
      fi
      if test $use_ed448 = "yes"; then
      		AC_DEFINE_UNQUOTED([USE_ED448], [1], [Define this to enable ED448 support.])
      fi
      ;;
esac

AC_ARG_ENABLE(event-api, AC_HELP_STRING([--enable-event-api], [Enable (experimental) pluggable event base libunbound API installed to unbound-event.h]))
case "$enable_event_api" in
    yes)
      AC_SUBST(UNBOUND_EVENT_INSTALL, [unbound-event-install])
      AC_SUBST(UNBOUND_EVENT_UNINSTALL, [unbound-event-uninstall])
      ;;
    *)
      ;;
esac

AC_ARG_ENABLE(tfo-client, AC_HELP_STRING([--enable-tfo-client], [Enable TCP Fast Open for client mode]))
case "$enable_tfo_client" in
	yes)
		case `uname` in
			Linux) AC_CHECK_DECL([MSG_FASTOPEN], [AC_MSG_WARN([Check the platform specific TFO kernel parameters are correctly configured to support client mode TFO])],
			                     [AC_MSG_ERROR([TCP Fast Open is not available for client mode: please rerun without --enable-tfo-client])], 
			                     [AC_INCLUDES_DEFAULT 
#include <netinet/tcp.h>
])
					AC_DEFINE_UNQUOTED([USE_MSG_FASTOPEN], [1], [Define this to enable client TCP Fast Open.])
			  ;;
			Darwin) AC_CHECK_DECL([CONNECT_RESUME_ON_READ_WRITE], [AC_MSG_WARN([Check the platform specific TFO kernel parameters are correctly configured to support client mode TFO])], 
			                      [AC_MSG_ERROR([TCP Fast Open is not available for client mode: please rerun without --enable-tfo-client])], 
			                      [AC_INCLUDES_DEFAULT
#include <sys/socket.h>
])
					AC_DEFINE_UNQUOTED([USE_OSX_MSG_FASTOPEN], [1], [Define this to enable client TCP Fast Open.])
			  ;;
		esac
	;;
	no|*)
		;;
esac

AC_ARG_ENABLE(tfo-server, AC_HELP_STRING([--enable-tfo-server], [Enable TCP Fast Open for server mode]))
case "$enable_tfo_server" in
	yes)
	      AC_CHECK_DECL([TCP_FASTOPEN], [AC_MSG_WARN([Check the platform specific TFO kernel parameters are correctly configured to support server mode TFO])], [AC_MSG_ERROR([TCP Fast Open is not available for server mode: please rerun without --enable-tfo-server])], [AC_INCLUDES_DEFAULT
#include <netinet/tcp.h>
	      ])
		AC_DEFINE_UNQUOTED([USE_TCP_FASTOPEN], [1], [Define this to enable server TCP Fast Open.])
		;;
	no|*)
		;;
esac

# check for libevent
AC_ARG_WITH(libevent, AC_HELP_STRING([--with-libevent=pathname],
    [use libevent (will check /usr/local /opt/local /usr/lib /usr/pkg /usr/sfw /usr  or you can specify an explicit path). Slower, but allows use of large outgoing port ranges.]),
    [ ],[ withval="no" ])
if test x_$withval = x_yes -o x_$withval != x_no; then
        AC_MSG_CHECKING(for libevent)
        if test x_$withval = x_ -o x_$withval = x_yes; then
            withval="/usr/local /opt/local /usr/lib /usr/pkg /usr/sfw /usr"
        fi
        for dir in $withval; do
            thedir="$dir"
            if test -f "$dir/include/event.h" -o -f "$dir/include/event2/event.h"; then
                found_libevent="yes"
		dnl assume /usr is in default path.
		if test "$thedir" != "/usr"; then
                    CPPFLAGS="$CPPFLAGS -I$thedir/include"
		fi
                break;
            fi
        done
        if test x_$found_libevent != x_yes; then
		if test -f "$dir/event.h" -a \( -f "$dir/libevent.la" -o -f "$dir/libev.la" \) ; then
			# libevent source directory
            		AC_MSG_RESULT(found in $thedir)
                	CPPFLAGS="$CPPFLAGS -I$thedir -I$thedir/include"
			BAK_LDFLAGS_SET="1"
			BAK_LDFLAGS="$LDFLAGS"
			# remove evdns from linking
			mkdir build >/dev/null 2>&1
			mkdir build/libevent >/dev/null 2>&1
			mkdir build/libevent/.libs >/dev/null 2>&1
			ev_files_o=`ls $thedir/*.o | grep -v evdns\.o | grep -v bufferevent_openssl\.o`
			ev_files_lo=`ls $thedir/*.lo | grep -v evdns\.lo | grep -v bufferevent_openssl\.lo`
			ev_files_libso=`ls $thedir/.libs/*.o | grep -v evdns\.o | grep -v bufferevent_openssl\.o`
			cp $ev_files_o build/libevent
			cp $ev_files_lo build/libevent
			cp $ev_files_libso build/libevent/.libs
            		LATE_LDFLAGS="build/libevent/*.lo -lm"
			LDFLAGS="build/libevent/*.o $LDFLAGS -lm"
		else
            		AC_MSG_ERROR([Cannot find the libevent library in $withval
You can restart ./configure --with-libevent=no to use a builtin alternative.
Please note that this alternative is not as capable as libevent when using
large outgoing port ranges.  ])
		fi
        else
            AC_MSG_RESULT(found in $thedir)
	    dnl if event2 exists and no event lib in dir itself, use subdir
	    if test ! -f $thedir/lib/libevent.a -a ! -f $thedir/lib/libevent.so -a -d "$thedir/lib/event2"; then
		    LDFLAGS="$LDFLAGS -L$thedir/lib/event2"
		    ACX_RUNTIME_PATH_ADD([$thedir/lib/event2])
	    else
		    dnl assume /usr is in default path, do not add "".
		    if test "$thedir" != "/usr" -a "$thedir" != ""; then
			LDFLAGS="$LDFLAGS -L$thedir/lib"
			ACX_RUNTIME_PATH_ADD([$thedir/lib])
		    fi
	    fi
        fi
	# check for library used by libevent after 1.3c
	AC_SEARCH_LIBS([clock_gettime], [rt])

	# is the event.h header libev or libevent?
	AC_CHECK_HEADERS([event.h],,, [AC_INCLUDES_DEFAULT])
	AC_CHECK_DECL(EV_VERSION_MAJOR, [
		AC_SEARCH_LIBS(event_set, [ev])
	],[
		AC_SEARCH_LIBS(event_set, [event])
	],[AC_INCLUDES_DEFAULT
#include <event.h>
	])
	AC_CHECK_FUNCS([event_base_free]) # only in libevent 1.2 and later
	AC_CHECK_FUNCS([event_base_once]) # only in libevent 1.4.1 and later
	AC_CHECK_FUNCS([event_base_new]) # only in libevent 1.4.1 and later
	AC_CHECK_FUNCS([event_base_get_method]) # only in libevent 1.4.3 and later
	AC_CHECK_FUNCS([ev_loop]) # only in libev. (tested on 3.51)
	AC_CHECK_FUNCS([ev_default_loop]) # only in libev. (tested on 4.00)
	AC_CHECK_FUNCS([event_assign]) # in libevent, for thread-safety
	AC_CHECK_DECLS([evsignal_assign], [], [], [AC_INCLUDES_DEFAULT
#ifdef HAVE_EVENT_H
#  include <event.h>
#else
#  include "event2/event.h"
#endif
	])
        PC_LIBEVENT_DEPENDENCY="libevent"
        AC_SUBST(PC_LIBEVENT_DEPENDENCY)
	if test -n "$BAK_LDFLAGS_SET"; then
		LDFLAGS="$BAK_LDFLAGS"
	fi
else
	AC_DEFINE(USE_MINI_EVENT, 1, [Define if you want to use internal select based events])
fi

# check for libexpat
AC_ARG_WITH(libexpat, AC_HELP_STRING([--with-libexpat=path],
    [specify explicit path for libexpat.]),
    [ ],[ withval="/usr/local /opt/local /usr/lib /usr/pkg /usr/sfw /usr" ])
AC_MSG_CHECKING(for libexpat)
found_libexpat="no"
for dir in $withval ; do
            if test -f "$dir/include/expat.h"; then
		found_libexpat="yes"
		dnl assume /usr is in default path.
		if test "$dir" != "/usr"; then
                    CPPFLAGS="$CPPFLAGS -I$dir/include"
		    LDFLAGS="$LDFLAGS -L$dir/lib"
		fi
            	AC_MSG_RESULT(found in $dir)
                break;
            fi
done
if test x_$found_libexpat != x_yes; then
	AC_ERROR([Could not find libexpat, expat.h])
fi
AC_CHECK_HEADERS([expat.h],,, [AC_INCLUDES_DEFAULT])
AC_CHECK_DECLS([XML_StopParser], [], [], [AC_INCLUDES_DEFAULT
#include <expat.h>
])

# hiredis (redis C client for cachedb)
AC_ARG_WITH(libhiredis, AC_HELP_STRING([--with-libhiredis=path],
    [specify explicit path for libhiredis.]),
    [ ],[ withval="no" ])
found_libhiredis="no"
if test x_$withval = x_yes -o x_$withval != x_no; then
   AC_MSG_CHECKING(for libhiredis)
   if test x_$withval = x_ -o x_$withval = x_yes; then
            withval="/usr/local /opt/local /usr/lib /usr/pkg /usr/sfw /usr"
   fi
   for dir in $withval ; do
            if test -f "$dir/include/hiredis/hiredis.h"; then
		found_libhiredis="yes"
		dnl assume /usr is in default path.
		if test "$dir" != "/usr"; then
                    CPPFLAGS="$CPPFLAGS -I$dir/include"
		    LDFLAGS="$LDFLAGS -L$dir/lib"
		fi
		AC_MSG_RESULT(found in $dir)
		AC_DEFINE([USE_REDIS], [1], [Define this to use hiredis client.])
		LIBS="$LIBS -lhiredis"
                break;
            fi
    done
    if test x_$found_libhiredis != x_yes; then
	AC_ERROR([Could not find libhiredis, hiredis.h])
    fi
    AC_CHECK_HEADERS([hiredis/hiredis.h],,, [AC_INCLUDES_DEFAULT])
    AC_CHECK_DECLS([redisConnect], [], [], [AC_INCLUDES_DEFAULT
    #include <hiredis/hiredis.h>
    ])
fi

# set static linking if requested
AC_SUBST(staticexe)
staticexe=""
AC_ARG_ENABLE(static-exe, AC_HELP_STRING([--enable-static-exe],
	[ enable to compile executables statically against (event) libs, for debug purposes ]), 
	, )
if test x_$enable_static_exe = x_yes; then
	staticexe="-static"
	if test "$on_mingw" = yes; then
		staticexe="-all-static"
		# for static compile, include gdi32 and zlib here.
		if echo $LIBS | grep 'lgdi32' >/dev/null; then
			:
		else
			LIBS="$LIBS -lgdi32"
		fi
		LIBS="$LIBS -lz"
	fi
fi

# set lock checking if requested
AC_ARG_ENABLE(lock_checks, AC_HELP_STRING([--enable-lock-checks],
	[ enable to check lock and unlock calls, for debug purposes ]), 
	, )
if test x_$enable_lock_checks = x_yes; then
	AC_DEFINE(ENABLE_LOCK_CHECKS, 1, [Define if you want to use debug lock checking (slow).])
	CHECKLOCK_OBJ="checklocks.lo"
	AC_SUBST(CHECKLOCK_OBJ)
fi

ACX_CHECK_GETADDRINFO_WITH_INCLUDES
if test "$USE_WINSOCK" = 1; then
	AC_DEFINE(UB_ON_WINDOWS, 1, [Use win32 resources and API])
	AC_CHECK_HEADERS([iphlpapi.h],,, [AC_INCLUDES_DEFAULT
#include <windows.h>
	])
	AC_CHECK_TOOL(WINDRES, windres)
	LIBS="$LIBS -liphlpapi -lcrypt32"
	WINAPPS="unbound-service-install.exe unbound-service-remove.exe anchor-update.exe"
	AC_SUBST(WINAPPS)
	WIN_DAEMON_SRC="winrc/win_svc.c winrc/w_inst.c"
	AC_SUBST(WIN_DAEMON_SRC)
	WIN_DAEMON_OBJ="win_svc.lo w_inst.lo"
	AC_SUBST(WIN_DAEMON_OBJ)
	WIN_DAEMON_OBJ_LINK="rsrc_unbound.o"
	AC_SUBST(WIN_DAEMON_OBJ_LINK)
	WIN_HOST_OBJ_LINK="rsrc_unbound_host.o"
	AC_SUBST(WIN_HOST_OBJ_LINK)
	WIN_UBANCHOR_OBJ_LINK="rsrc_unbound_anchor.o log.lo locks.lo"
	AC_SUBST(WIN_UBANCHOR_OBJ_LINK)
	WIN_CONTROL_OBJ_LINK="rsrc_unbound_control.o"
	AC_SUBST(WIN_CONTROL_OBJ_LINK)
	WIN_CHECKCONF_OBJ_LINK="rsrc_unbound_checkconf.o"
	AC_SUBST(WIN_CHECKCONF_OBJ_LINK)
fi
if test $ac_cv_func_getaddrinfo = no; then
	AC_LIBOBJ([fake-rfc2553])
fi
# check after getaddrinfo for its libraries
ACX_FUNC_IOCTLSOCKET

# see if daemon(3) exists, and if it is deprecated.
AC_CHECK_FUNCS([daemon])
if test $ac_cv_func_daemon = yes; then
	ACX_FUNC_DEPRECATED([daemon], [(void)daemon(0, 0);], [
#include <stdlib.h>
])
fi

AC_CHECK_MEMBERS([struct sockaddr_un.sun_len],,,[
AC_INCLUDES_DEFAULT
#ifdef HAVE_SYS_UN_H
#include <sys/un.h>
#endif
])
AC_CHECK_MEMBERS([struct in_pktinfo.ipi_spec_dst],,,[
AC_INCLUDES_DEFAULT
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif

#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif

#ifdef HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#ifdef HAVE_NETINET_TCP_H
#include <netinet/tcp.h>
#endif

#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif

#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#endif

#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
])
AC_SEARCH_LIBS([setusercontext], [util])
AC_CHECK_FUNCS([tzset sigprocmask fcntl getpwnam endpwent getrlimit setrlimit setsid chroot kill chown sleep usleep random srandom recvmsg sendmsg writev socketpair glob initgroups strftime localtime_r setusercontext _beginthreadex endservent endprotoent fsync shmget accept4])
AC_CHECK_FUNCS([setresuid],,[AC_CHECK_FUNCS([setreuid])])
AC_CHECK_FUNCS([setresgid],,[AC_CHECK_FUNCS([setregid])])

# check if setreuid en setregid fail, on MacOSX10.4(darwin8).
if echo $target_os | grep darwin8 > /dev/null; then
	AC_DEFINE(DARWIN_BROKEN_SETREUID, 1, [Define this if on macOSX10.4-darwin8 and setreuid and setregid do not work])
fi
AC_CHECK_DECLS([inet_pton,inet_ntop], [], [], [
AC_INCLUDES_DEFAULT
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#ifdef HAVE_NETINET_TCP_H
#include <netinet/tcp.h>
#endif

#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif

#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#endif

#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
])
AC_REPLACE_FUNCS(inet_aton)
AC_REPLACE_FUNCS(inet_pton)
AC_REPLACE_FUNCS(inet_ntop)
AC_REPLACE_FUNCS(snprintf)
# test if snprintf return the proper length
if test "x$ac_cv_func_snprintf" = xyes; then
    if test c${cross_compiling} = cno; then
	AC_MSG_CHECKING([for correct snprintf return value])
	AC_RUN_IFELSE([AC_LANG_SOURCE(AC_INCLUDES_DEFAULT
[[
int main(void) { return !(snprintf(NULL, 0, "test") == 4); }
]])], [AC_MSG_RESULT(yes)], [
		AC_MSG_RESULT(no)
		AC_DEFINE([SNPRINTF_RET_BROKEN], [], [define if (v)snprintf does not return length needed, (but length used)])
		AC_LIBOBJ(snprintf)
	  ])
    fi
fi
AC_REPLACE_FUNCS(strlcat)
AC_REPLACE_FUNCS(strlcpy)
AC_REPLACE_FUNCS(memmove)
AC_REPLACE_FUNCS(gmtime_r)
AC_REPLACE_FUNCS(isblank)
AC_REPLACE_FUNCS(explicit_bzero)
dnl without CTIME, ARC4-functions and without reallocarray.
LIBOBJ_WITHOUT_CTIMEARC4="$LIBOBJS"
AC_SUBST(LIBOBJ_WITHOUT_CTIMEARC4)
AC_MSG_CHECKING([for reallocarray])
AC_LINK_IFELSE([AC_LANG_SOURCE(AC_INCLUDES_DEFAULT
[[
#ifndef _OPENBSD_SOURCE
#define _OPENBSD_SOURCE 1
#endif
#include <stdlib.h>
int main(void) {
	void* p = reallocarray(NULL, 10, 100);
	free(p);
	return 0;
}
]])], [AC_MSG_RESULT(yes)
	AC_DEFINE(HAVE_REALLOCARRAY, 1, [If we have reallocarray(3)])
], [
	AC_MSG_RESULT(no)
	AC_LIBOBJ(reallocarray)
])
if test "$USE_NSS" = "no"; then
	AC_REPLACE_FUNCS(arc4random)
	AC_REPLACE_FUNCS(arc4random_uniform)
	if test "$ac_cv_func_arc4random" = "no"; then
		AC_LIBOBJ(arc4_lock)
		AC_CHECK_FUNCS([getentropy],,[
		    if test "$USE_WINSOCK" = 1; then
			AC_LIBOBJ(getentropy_win)
		    else
			case "$host" in
			Darwin|*darwin*)
				AC_LIBOBJ(getentropy_osx)
			;;
			*solaris*|*sunos*|SunOS)
				AC_LIBOBJ(getentropy_solaris)
				AC_CHECK_HEADERS([sys/sha2.h],, [
					AC_CHECK_FUNCS([SHA512_Update],,[
						AC_LIBOBJ(sha512)
					])
				], [AC_INCLUDES_DEFAULT])
				if test "$ac_cv_header_sys_sha2_h" = "yes"; then
					# this lib needed for sha2 on solaris
					LIBS="$LIBS -lmd"
				fi
				AC_SEARCH_LIBS([clock_gettime], [rt])
			;;
			*linux*|Linux|*)
				AC_LIBOBJ(getentropy_linux)
				AC_CHECK_FUNCS([SHA512_Update],,[
					AC_DEFINE([COMPAT_SHA512], [1], [Do sha512 definitions in config.h])
					AC_LIBOBJ(sha512)
				])
				AC_CHECK_HEADERS([sys/sysctl.h],,, [AC_INCLUDES_DEFAULT])
				AC_CHECK_FUNCS([getauxval])
				AC_SEARCH_LIBS([clock_gettime], [rt])
			;;
			esac
		    fi
		])
	fi
fi
LIBOBJ_WITHOUT_CTIME="$LIBOBJS"
AC_SUBST(LIBOBJ_WITHOUT_CTIME)
AC_REPLACE_FUNCS(ctime_r)
AC_REPLACE_FUNCS(strsep)

AC_ARG_ENABLE(allsymbols, AC_HELP_STRING([--enable-allsymbols], [export all symbols from libunbound and link binaries to it, smaller install size but libunbound export table is polluted by internal symbols]))
case "$enable_allsymbols" in
	yes)
	COMMON_OBJ_ALL_SYMBOLS=""
	UBSYMS=""
	EXTRALINK="-L. -L.libs -lunbound"
	AC_DEFINE(EXPORT_ALL_SYMBOLS, 1, [Define this if you enabled-allsymbols from libunbound to link binaries to it for smaller install size, but the libunbound export table is polluted by internal symbols])
	;;
	no|*)
	COMMON_OBJ_ALL_SYMBOLS='$(COMMON_OBJ)'
	UBSYMS='-export-symbols $(srcdir)/libunbound/ubsyms.def'
	EXTRALINK=""
	;;
esac
AC_SUBST(COMMON_OBJ_ALL_SYMBOLS)
AC_SUBST(EXTRALINK)
AC_SUBST(UBSYMS)
if test x_$enable_lock_checks = x_yes; then
	UBSYMS="-export-symbols clubsyms.def"
	cp ${srcdir}/libunbound/ubsyms.def clubsyms.def
	echo lock_protect >> clubsyms.def
	echo lock_unprotect >> clubsyms.def
	echo lock_get_mem >> clubsyms.def
	echo checklock_start >> clubsyms.def
	echo checklock_stop >> clubsyms.def
	echo checklock_lock >> clubsyms.def
	echo checklock_unlock >> clubsyms.def
	echo checklock_init >> clubsyms.def
	echo checklock_thrcreate >> clubsyms.def
	echo checklock_thrjoin >> clubsyms.def
fi

# check for dnstap if requested
dt_DNSTAP([$UNBOUND_RUN_DIR/dnstap.sock],
    [
        AC_DEFINE([USE_DNSTAP], [1], [Define to 1 to enable dnstap support])
        AC_SUBST([ENABLE_DNSTAP], [1])

        AC_SUBST([opt_dnstap_socket_path])
        ACX_ESCAPE_BACKSLASH($opt_dnstap_socket_path, hdr_dnstap_socket_path)
        AC_DEFINE_UNQUOTED(DNSTAP_SOCKET_PATH,
            ["$hdr_dnstap_socket_path"], [default dnstap socket path])

        AC_SUBST([DNSTAP_SRC], ["dnstap/dnstap.c dnstap/dnstap.pb-c.c"])
        AC_SUBST([DNSTAP_OBJ], ["dnstap.lo dnstap.pb-c.lo"])
    ],
    [
        AC_SUBST([ENABLE_DNSTAP], [0])
    ]
)

# check for dnscrypt if requested
dnsc_DNSCRYPT([
        AC_DEFINE([USE_DNSCRYPT], [1], [Define to 1 to enable dnscrypt support])
        AC_SUBST([ENABLE_DNSCRYPT], [1])

        AC_SUBST([DNSCRYPT_SRC], ["dnscrypt/dnscrypt.c"])
        AC_SUBST([DNSCRYPT_OBJ], ["dnscrypt.lo"])
    ],
    [
        AC_SUBST([ENABLE_DNSCRYPT], [0])
    ]
)

# check for cachedb if requested
AC_ARG_ENABLE(cachedb, AC_HELP_STRING([--enable-cachedb], [enable cachedb module that can use external cache storage]))
# turn on cachedb when hiredis support is enabled.
if test "$found_libhiredis" = "yes"; then enable_cachedb="yes"; fi
case "$enable_cachedb" in
    yes)
    	AC_DEFINE([USE_CACHEDB], [1], [Define to 1 to use cachedb support])
    	;;
    no|*)
    	# nothing
    	;;
esac

# check for ipsecmod if requested
AC_ARG_ENABLE(ipsecmod, AC_HELP_STRING([--enable-ipsecmod], [Enable ipsecmod module that facilitates opportunistic IPsec]))
case "$enable_ipsecmod" in
	yes)
		AC_DEFINE([USE_IPSECMOD], [1], [Define to 1 to use ipsecmod support.])
		IPSECMOD_OBJ="ipsecmod.lo ipsecmod-whitelist.lo"
		AC_SUBST(IPSECMOD_OBJ)
		IPSECMOD_HEADER='$(srcdir)/ipsecmod/ipsecmod.h $(srcdir)/ipsecmod/ipsecmod-whitelist.h'
		AC_SUBST(IPSECMOD_HEADER)
		;;
	no|*)
		# nothing
		;;
esac

# check for ipset if requested
AC_ARG_ENABLE(ipset, AC_HELP_STRING([--enable-ipset], [enable ipset module]))
case "$enable_ipset" in
    yes)
		AC_DEFINE([USE_IPSET], [1], [Define to 1 to use ipset support])
		IPSET_SRC="ipset/ipset.c"
		AC_SUBST(IPSET_SRC)
		IPSET_OBJ="ipset.lo"
		AC_SUBST(IPSET_OBJ)

		# mnl
		AC_ARG_WITH(libmnl, AC_HELP_STRING([--with-libmnl=path],
			[specify explicit path for libmnl.]),
			[ ],[ withval="yes" ])
		found_libmnl="no"
		AC_MSG_CHECKING(for libmnl)
		if test x_$withval = x_ -o x_$withval = x_yes; then
			withval="/usr/local /opt/local /usr/lib /usr/pkg /usr/sfw /usr"
		fi
		for dir in $withval ; do
			if test -f "$dir/include/libmnl/libmnl.h"; then
				found_libmnl="yes"
				dnl assume /usr is in default path.
				if test "$dir" != "/usr"; then
					CPPFLAGS="$CPPFLAGS -I$dir/include"
					LDFLAGS="$LDFLAGS -L$dir/lib"
				fi
				AC_MSG_RESULT(found in $dir)
				LIBS="$LIBS -lmnl"
				break;
			fi
		done
		if test x_$found_libmnl != x_yes; then
			AC_ERROR([Could not find libmnl, libmnl.h])
		fi
		;;
    no|*)
    	# nothing
		;;
esac

AC_MSG_CHECKING([if ${MAKE:-make} supports $< with implicit rule in scope])
# on openBSD, the implicit rule make $< work.
# on Solaris, it does not work ($? is changed sources, $^ lists dependencies).
# gmake works.
cat >conftest.make <<EOF
all:	conftest.lo

conftest.lo foo.lo bla.lo:
	if test -f "\$<"; then touch \$@; fi

.SUFFIXES: .lo
.c.lo:
	if test -f "\$<"; then touch \$@; fi

conftest.lo:        conftest.dir/conftest.c
EOF
mkdir conftest.dir
touch conftest.dir/conftest.c
rm -f conftest.lo conftest.c
${MAKE:-make} -f conftest.make >/dev/null
rm -f conftest.make conftest.c conftest.dir/conftest.c
rm -rf conftest.dir
if test ! -f conftest.lo; then
	AC_MSG_RESULT(no)
	SOURCEDETERMINE='echo "$^" | awk "-F " "{print \$$1;}" > .source'
	SOURCEFILE='`cat .source`'
else
	AC_MSG_RESULT(yes)
	SOURCEDETERMINE=':'
	SOURCEFILE='$<'
fi
rm -f conftest.lo
AC_SUBST(SOURCEDETERMINE)
AC_SUBST(SOURCEFILE)

# see if we want to build the library or everything
ALLTARGET="alltargets"
INSTALLTARGET="install-all"
AC_ARG_WITH(libunbound-only, AC_HELP_STRING([--with-libunbound-only],
	[do not build daemon and tool programs]),
	[
	if test "$withval" = "yes"; then
		ALLTARGET="lib"
		INSTALLTARGET="install-lib"
	fi
])
if test $ALLTARGET = "alltargets"; then
	if test $USE_NSS = "yes"; then 
		AC_ERROR([--with-nss can only be used in combination with --with-libunbound-only.])	
	fi
	if test $USE_NETTLE = "yes"; then
		AC_ERROR([--with-nettle can only be used in combination with --with-libunbound-only.])	
	fi
fi

AC_SUBST(ALLTARGET)
AC_SUBST(INSTALLTARGET)

ACX_STRIP_EXT_FLAGS
if test -n "$LATE_LDFLAGS"; then
  LDFLAGS="$LATE_LDFLAGS $LDFLAGS"
fi
# remove start spaces 
LDFLAGS=`echo "$LDFLAGS"|sed -e 's/^ *//'`
LIBS=`echo "$LIBS"|sed -e 's/^ *//'`

AC_DEFINE_UNQUOTED([MAXSYSLOGMSGLEN], [10240], [Define to the maximum message length to pass to syslog.])

AH_BOTTOM(
dnl this must be first AH_CONFIG, to define the flags before any includes.
AHX_CONFIG_EXT_FLAGS

dnl includes
[
#ifndef _OPENBSD_SOURCE
#define _OPENBSD_SOURCE 1
#endif

#ifndef UNBOUND_DEBUG
# ifndef NDEBUG
#  define NDEBUG
# endif
#endif

/** Use small-ldns codebase */
#define USE_SLDNS 1
#ifdef HAVE_SSL
#  define LDNS_BUILD_CONFIG_HAVE_SSL 1
#endif

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>

#if STDC_HEADERS
#include <stdlib.h>
#include <stddef.h>
#endif

#ifdef HAVE_STDARG_H
#include <stdarg.h>
#endif

#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

#include <errno.h>

#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif

#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif

#ifdef HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#ifdef HAVE_NETINET_TCP_H
#include <netinet/tcp.h>
#endif

#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif

#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#endif

#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif

#ifndef USE_WINSOCK
#define ARG_LL "%ll"
#else
#define ARG_LL "%I64"
#endif

#ifndef AF_LOCAL
#define AF_LOCAL AF_UNIX
#endif
]

AHX_CONFIG_FORMAT_ATTRIBUTE
AHX_CONFIG_UNUSED_ATTRIBUTE
AHX_CONFIG_FSEEKO
AHX_CONFIG_MAXHOSTNAMELEN
#if !defined(HAVE_SNPRINTF) || defined(SNPRINTF_RET_BROKEN)
#define snprintf snprintf_unbound
#define vsnprintf vsnprintf_unbound
#include <stdarg.h>
int snprintf (char *str, size_t count, const char *fmt, ...);
int vsnprintf (char *str, size_t count, const char *fmt, va_list arg);
#endif /* HAVE_SNPRINTF or SNPRINTF_RET_BROKEN */
AHX_CONFIG_INET_PTON(unbound)
AHX_CONFIG_INET_NTOP(unbound)
AHX_CONFIG_INET_ATON(unbound)
AHX_CONFIG_MEMMOVE(unbound)
AHX_CONFIG_STRLCAT(unbound)
AHX_CONFIG_STRLCPY(unbound)
AHX_CONFIG_GMTIME_R(unbound)
AHX_CONFIG_REALLOCARRAY(unbound)
AHX_CONFIG_W32_SLEEP
AHX_CONFIG_W32_USLEEP
AHX_CONFIG_W32_RANDOM
AHX_CONFIG_W32_SRANDOM
AHX_CONFIG_W32_FD_SET_T
AHX_CONFIG_IPV6_MIN_MTU
AHX_MEMCMP_BROKEN(unbound)

[
#ifndef HAVE_CTIME_R
#define ctime_r unbound_ctime_r
char *ctime_r(const time_t *timep, char *buf);
#endif

#ifndef HAVE_STRSEP
#define strsep unbound_strsep
char *strsep(char **stringp, const char *delim);
#endif

#ifndef HAVE_ISBLANK
#define isblank unbound_isblank
int isblank(int c);
#endif

#ifndef HAVE_EXPLICIT_BZERO
#define explicit_bzero unbound_explicit_bzero
void explicit_bzero(void* buf, size_t len);
#endif

#if defined(HAVE_INET_NTOP) && !HAVE_DECL_INET_NTOP
const char *inet_ntop(int af, const void *src, char *dst, size_t size);
#endif

#if defined(HAVE_INET_PTON) && !HAVE_DECL_INET_PTON
int inet_pton(int af, const char* src, void* dst);
#endif

#if !defined(HAVE_STRPTIME) || !defined(STRPTIME_WORKS)
#define strptime unbound_strptime
struct tm;
char *strptime(const char *s, const char *format, struct tm *tm);
#endif

#ifdef HAVE_LIBRESSL
#  if !HAVE_DECL_STRLCPY
size_t strlcpy(char *dst, const char *src, size_t siz);
#  endif
#  if !HAVE_DECL_STRLCAT
size_t strlcat(char *dst, const char *src, size_t siz);
#  endif
#  if !HAVE_DECL_ARC4RANDOM && defined(HAVE_ARC4RANDOM)
uint32_t arc4random(void);
#  endif
#  if !HAVE_DECL_ARC4RANDOM_UNIFORM && defined(HAVE_ARC4RANDOM_UNIFORM)
uint32_t arc4random_uniform(uint32_t upper_bound);
#  endif
#  if !HAVE_DECL_REALLOCARRAY
void *reallocarray(void *ptr, size_t nmemb, size_t size);
#  endif
#endif /* HAVE_LIBRESSL */
#ifndef HAVE_ARC4RANDOM
int getentropy(void* buf, size_t len);
uint32_t arc4random(void);
void arc4random_buf(void* buf, size_t n);
void _ARC4_LOCK(void);
void _ARC4_UNLOCK(void);
void _ARC4_LOCK_DESTROY(void);
#endif
#ifndef HAVE_ARC4RANDOM_UNIFORM
uint32_t arc4random_uniform(uint32_t upper_bound);
#endif
#ifdef COMPAT_SHA512
#ifndef SHA512_DIGEST_LENGTH
#define SHA512_BLOCK_LENGTH		128
#define SHA512_DIGEST_LENGTH		64
#define SHA512_DIGEST_STRING_LENGTH	(SHA512_DIGEST_LENGTH * 2 + 1)
typedef struct _SHA512_CTX {
	uint64_t	state[8];
	uint64_t	bitcount[2];
	uint8_t	buffer[SHA512_BLOCK_LENGTH];
} SHA512_CTX;
#endif /* SHA512_DIGEST_LENGTH */
void SHA512_Init(SHA512_CTX*);
void SHA512_Update(SHA512_CTX*, void*, size_t);
void SHA512_Final(uint8_t[SHA512_DIGEST_LENGTH], SHA512_CTX*);
unsigned char *SHA512(void* data, unsigned int data_len, unsigned char *digest);
#endif /* COMPAT_SHA512 */



#if defined(HAVE_EVENT_H) && !defined(HAVE_EVENT_BASE_ONCE) && !(defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)) && (defined(HAVE_PTHREAD) || defined(HAVE_SOLARIS_THREADS))
   /* using version of libevent that is not threadsafe. */
#  define LIBEVENT_SIGNAL_PROBLEM 1
#endif

#ifndef CHECKED_INET6
#  define CHECKED_INET6
#  ifdef AF_INET6
#    define INET6
#  else
#    define AF_INET6        28
#  endif
#endif /* CHECKED_INET6 */

#ifndef HAVE_GETADDRINFO
struct sockaddr_storage;
#include "compat/fake-rfc2553.h"
#endif

#ifdef UNBOUND_ALLOC_STATS
#  define malloc(s) unbound_stat_malloc_log(s, __FILE__, __LINE__, __func__)
#  define calloc(n,s) unbound_stat_calloc_log(n, s, __FILE__, __LINE__, __func__)
#  define free(p) unbound_stat_free_log(p, __FILE__, __LINE__, __func__)
#  define realloc(p,s) unbound_stat_realloc_log(p, s, __FILE__, __LINE__, __func__)
void *unbound_stat_malloc(size_t size);
void *unbound_stat_calloc(size_t nmemb, size_t size);
void unbound_stat_free(void *ptr);
void *unbound_stat_realloc(void *ptr, size_t size);
void *unbound_stat_malloc_log(size_t size, const char* file, int line,
	const char* func);
void *unbound_stat_calloc_log(size_t nmemb, size_t size, const char* file,
	int line, const char* func);
void unbound_stat_free_log(void *ptr, const char* file, int line,
	const char* func);
void *unbound_stat_realloc_log(void *ptr, size_t size, const char* file,
	int line, const char* func);
#elif defined(UNBOUND_ALLOC_LITE)
#  include "util/alloc.h"
#endif /* UNBOUND_ALLOC_LITE and UNBOUND_ALLOC_STATS */

/** default port for DNS traffic. */
#define UNBOUND_DNS_PORT 53
/** default port for DNS over TLS traffic. */
#define UNBOUND_DNS_OVER_TLS_PORT 853
/** default port for unbound control traffic, registered port with IANA,
    ub-dns-control  8953/tcp    unbound dns nameserver control */
#define UNBOUND_CONTROL_PORT 8953
/** the version of unbound-control that this software implements */
#define UNBOUND_CONTROL_VERSION 1

])

dnl if we build from source tree, the man pages need @date@ and @version@
dnl if this is a distro tarball, that was already done by makedist.sh
AC_SUBST(version, [VERSION_MAJOR.VERSION_MINOR.VERSION_MICRO])
AC_SUBST(date, [`date +'%b %e, %Y'`])

AC_CONFIG_FILES([Makefile doc/example.conf doc/libunbound.3 doc/unbound.8 doc/unbound-anchor.8 doc/unbound-checkconf.8 doc/unbound.conf.5 doc/unbound-control.8 doc/unbound-host.1 smallapp/unbound-control-setup.sh dnstap/dnstap_config.h dnscrypt/dnscrypt_config.h])
AC_CONFIG_HEADER([config.h])
AC_OUTPUT