configure.in

	ac_cv_func_res_query=$ac_cv_func___res_query
fi

if test $ac_cv_func_res_query = no ; then 
	AC_CHECK_LIB(bind, res_query)
	ac_cv_func_res_query=$ac_cv_lib_bind_res_query
fi

if test $ac_cv_func_res_query = no ; then 
	AC_CHECK_LIB(bind, __res_query)
	ac_cv_func_res_query=$ac_cv_lib_bind___res_query
fi

if test $ac_cv_func_res_query = no ; then 
	AC_CHECK_LIB(resolv, res_query)
	ac_cv_func_res_query=$ac_cv_lib_resolv_res_query
fi

if test $ac_cv_func_res_query = no ; then 
	AC_CHECK_LIB(resolv, __res_query)
	ac_cv_func_res_query=$ac_cv_lib_resolv___res_query
fi

if test "$ac_cv_func_res_query" = yes ; then
	AC_DEFINE(HAVE_RES_QUERY,1,
		[define if you have res_query()])

	if test $ol_enable_dnssrv != no ; then
		ol_link_dnssrv=yes
	fi
fi

if test "$ol_enable_dnssrv" = yes -a "$ol_link_dnssrv" = no ; then
	AC_MSG_ERROR([DNSSRV requires res_query()])
fi

dnl ----------------------------------------------------------------
dnl PF_INET6 support requires getaddrinfo and INET6_ADDRSTRLEN
dnl PF_LOCAL may use getaddrinfo in available
AC_CHECK_FUNCS( getaddrinfo getnameinfo gai_strerror inet_ntop )

ol_link_ipv6=no
if test $ac_cv_func_getaddrinfo = no -o $ac_cv_func_inet_ntop = no ; then
	if test $ol_enable_ipv6 = yes ; then
		AC_MSG_ERROR([IPv6 support requires getaddrinfo() and inet_ntop()])
	fi
elif test $ol_enable_ipv6 != no ; then
	AC_CACHE_CHECK([INET6_ADDRSTRLEN],[ol_cv_inet6_addrstrlen],[
		AC_EGREP_CPP(__has_inet6_addrstrlen__,[
#			include <netinet/in.h>
#			ifdef INET6_ADDRSTRLEN
				__has_inet6_addrstrlen__;
#			endif
		], [ol_cv_inet6_addrstrlen=yes], [ol_cv_inet6_addrstrlen=no])])


	AC_CACHE_CHECK([struct sockaddr_storage],ol_cv_struct_sockaddr_storage,[
		AC_TRY_COMPILE([
#include <sys/types.h>
#include <sys/socket.h>
],[
			struct sockaddr_storage ss;
],			[ol_cv_struct_sockaddr_storage=yes],
			[ol_cv_struct_sockaddr_storage=no])])

	if test $ol_cv_inet6_addrstrlen = yes \
		-a $ol_cv_struct_sockaddr_storage = yes ; then
		ol_link_ipv6=yes
	elif test $ol_enable_ipv6 = yes \
			-a $ol_cv_inet6_addrstrlen = no ; then
		AC_MSG_ERROR([IPv6 support requires INET6_ADDRSTRLEN])
	elif test $ol_enable_ipv6 = yes \
			-a $ol_cv_struct_sockaddr_storage = no ; then
		AC_MSG_ERROR([IPv6 support requires struct sockaddr_storage])
	fi
fi

if test $ol_enable_local != no ; then
	AC_CHECK_HEADERS( sys/un.h )

	if test $ol_enable_local = auto ; then
		ol_enable_local=$ac_cv_header_sys_un_h
	elif test $ac_cv_header_sys_un_h = no ; then
		AC_MSG_ERROR([AF_LOCAL domain support requires sys/un.h])
	fi
fi

dnl ----------------------------------------------------------------
dnl Kerberos
ol_link_kbind=no
ol_link_kpasswd=no
ol_link_krb5=no
ol_link_krb4=no

if test $ol_with_kerberos = yes -o $ol_with_kerberos = auto \
	-o $ol_with_kerberos = k5 -o $ol_with_kerberos = k5only \
	-o $ol_with_kerberos = k425 ; then

	AC_CHECK_HEADERS(krb5.h)

	if test $ac_cv_header_krb5_h = yes ; then
		dnl lazy check for Heimdal Kerberos
		AC_CHECK_HEADERS(heim_err.h)
		if test $ac_cv_header_heim_err_h = yes ; then
			krb5_impl=heimdal
		else
			krb5_impl=mit
		fi

		if test $krb5_impl = mit; then
			AC_CHECK_LIB(k5crypto, main,
				[krb5crypto=k5crypto],
				[krb5crypto=crypto])

			AC_CHECK_LIB(krb5, main,
				[have_krb5=yes
				KRB5_LIBS="-lkrb5 -l$krb5crypto -lcom_err"],
				[have_krb5=no],
				[-l$krb5crypto -lcom_err])

		elif test $krb5_impl = heimdal; then
			AC_CHECK_LIB(des, main,
				[krb5crypto=des],
				[krb5crypto=crypto])

			AC_CHECK_LIB(krb5, main,
				[have_krb5=yes
				KRB5_LIBS="-lkrb5 -l$krb5crypto -lasn1 -lroken -lcom_err"],
				[have_krb5=no],
				[-l$krb5crypto -lasn1 -lroken -lcom_err])

			AC_DEFINE(HAVE_HEIMDAL_KERBEROS, 1,
				[define if you have HEIMDAL Kerberos])

		else
			have_krb5=no
			AC_MSG_WARN([Unrecognized Kerberos5 Implementation])
		fi

		if test $have_krb5 = yes ; then
			ol_link_krb5=yes

			AC_DEFINE(HAVE_KRB5, 1,
				[define if you have Kerberos V])

			if test $ol_enable_kpasswd != no ; then
				ol_link_kpasswd=yes;
			fi

			if test $ol_with_kerberos = k5only ; then
				ol_with_kerberos=found
			fi

		elif test $ol_with_kerberos != auto ; then
			AC_MSG_ERROR([Required Kerberos 5 support not available])
		fi

	fi
fi

if test $ol_link_krb5 = yes -a \( $ol_with_kerberos = yes -o \
	$ol_with_kerberos = auto -o $ol_with_kerberos = k425 \) ; then

	AC_CHECK_HEADERS(kerberosIV/krb.h kerberosIV/des.h)

	if test $ac_cv_header_kerberosIV_krb_h = yes ; then
		if test $krb5_impl = mit; then
			AC_CHECK_LIB(krb4, main, [have_k425=yes
				KRB4_LIBS="-lkrb4 -ldes425"], [have_k425=no],
				[-ldes425 -lkrb5 -l$krb5crypto -lcom_err])

		elif test $krb5_impl = heimdal; then
			AC_CHECK_LIB(krb4, main, [have_k425=yes
				KRB4_LIBS="-lkrb4"], [have_k425=no],
				[-lkrb5 -l$krb5crypto -lasn1 -lroken -lcom_err])

		else
			have_425=no
			AC_MSG_WARN([Unrecongized Kerberos V Implementation])
		fi

		if test $have_k425 = yes ; then
			ol_with_kerberos=found
			ol_link_krb4=yes

			AC_DEFINE(HAVE_KRB425, 1,
				[define if you have Kerberos V with IV support])
			AC_DEFINE(HAVE_KRB4, 1,
				[define if you have Kerberos IV])

			AC_CACHE_CHECK([for des_debug in Kerberos libraries],
				[ol_cv_var_des_debug], [
				dnl save the flags
				save_LIBS="$LIBS"
				LIBS="$KRB4_LIBS $KRB5_LIBS $LIBS"
				AC_TRY_LINK([
#include <kerberosIV/krb.h>
#include <kerberosIV/des.h>
extern int des_debug;
],[
des_debug = 1;
],				ol_cv_var_des_debug=yes, ol_cv_var_des_debug=no)
				dnl restore the LIBS
				LIBS="$save_LIBS"
			])

			if test $ol_cv_var_des_debug = yes ; then
				AC_DEFINE(HAVE_DES_DEBUG,1,
					[define if you have Kerberos des_debug])
			fi

			LIBS="$save_LIBS"
		fi
	fi
fi

if test $ol_link_krb5 = yes ; then
	ol_with_kerberos=found
fi

if test $ol_with_kerberos = yes -o $ol_with_kerberos = auto \
	-o $ol_with_kerberos = k4 -o $ol_with_kerberos = kth ; then

	AC_CHECK_HEADERS(krb.h des.h krb-archaeology.h )

	if test $ac_cv_header_krb_h = yes ; then
		AC_CHECK_LIB(krb, main, [have_k4=yes], [have_k4=no], [-ldes])

		if test $have_k4 = yes ; then
			ol_with_kerberos=found
			ol_link_krb4=yes

			AC_DEFINE(HAVE_KRB4, 1,
				[define if you have Kerberos IV])

			KRB4_LIBS="-lkrb -ldes"

			if test $ac_cv_header_krb_archaeology_h = yes ; then
				AC_DEFINE(HAVE_KTH_KERBEROS, 1,
					[define if you have Kth Kerberos])
			fi
		fi
	fi
fi

if test $ol_link_krb4 = yes -a $ol_enable_kpasswd != no ; then
	ol_link_kpasswd=yes
fi

if test $ol_link_krb4 = yes -a $ol_enable_kbind != no ; then
	ol_link_kbind=yes

elif test $ol_enable_kbind = yes ; then
	AC_MSG_ERROR([Kerberos IV detection failed])
fi

if test $ol_link_krb4 = yes -o $ol_link_krb5 = yes ; then
	AC_DEFINE(HAVE_KERBEROS, 1, [define if you have Kerberos])

elif test $ol_with_kerberos != auto -a $ol_with_kerberos != no ; then
	AC_MSG_ERROR([Kerberos detection failed])
fi

dnl ----------------------------------------------------------------
dnl TLS/SSL
ol_link_tls=no
if test $ol_with_tls != no ; then
	AC_CHECK_HEADERS(openssl/ssl.h ssl.h)
	
	if test $ac_cv_header_openssl_ssl_h = yes \
		-o $ac_cv_header_ssl_h = yes ; then
		AC_CHECK_LIB(ssl, SSLeay_add_ssl_algorithms, 
			[have_ssleay=yes
			need_rsaref=no],
			[have_ssleay=no],
			[-lcrypto])
			
		if test $have_ssleay = no ; then
			AC_CHECK_LIB(ssl, SSL_library_init,
				[have_ssleay=yes
				need_rsaref=no], [have_ssleay=no],
				[-lcrypto])
		fi

		if test $have_ssleay = no ; then
			AC_CHECK_LIB(ssl, ssl3_accept, 
				[have_ssleay=yes
				need_rsaref=yes], [have_ssleay=no],
				[-lcrypto -lRSAglue -lrsaref])
		fi

		if test $have_ssleay = yes ; then
			ol_with_tls=found
			ol_link_tls=yes

			AC_DEFINE(HAVE_SSLEAY, 1, 
				[define if you have SSLeay or OpenSSL])

			if test $need_rsaref = yes; then
				AC_DEFINE(HAVE_RSAREF, 1, 
					[define if you have RSAref])

				TLS_LIBS="-lssl -lcrypto -lRSAglue -lrsaref"
			else
				TLS_LIBS="-lssl -lcrypto"
			fi
		fi
	fi

else
	AC_WARN([TLS data protection not supported!])
fi

if test $ol_link_tls = yes ; then
	AC_DEFINE(HAVE_TLS, 1, [define if you have TLS])

elif test $ol_with_tls = auto ; then
	AC_WARN([Could not locate TLS/SSL package])
	AC_WARN([TLS data protection not supported!])

elif test $ol_with_tls != no ; then
	AC_ERROR([Could not locate TLS/SSL package])
fi

dnl ----------------------------------------------------------------
dnl LAN Manger password checking requires DES from OpenSSL
if test $ol_enable_lmpasswd != no; then
	if test $ol_link_tls != yes ; then
		AC_ERROR([LAN Manager passwords require OpenSSL])
	fi

	AC_DEFINE(SLAPD_LMHASH, 1, [define to support LAN Manager passwords])
fi

dnl ----------------------------------------------------------------
dnl Threads?
ol_link_threads=no

if test $ol_with_threads = auto -o $ol_with_threads = yes \
	-o $ol_with_threads = nt ; then

	OL_NT_THREADS

	if test "$ol_cv_nt_threads" = yes ; then
		ol_link_threads=nt
		ol_with_threads=found
		ol_with_yielding_select=yes

		AC_DEFINE(HAVE_NT_SERVICE_MANAGER,1,[if you have NT Service Manager])
		AC_DEFINE(HAVE_NT_EVENT_LOG,1,[if you have NT Event Log])
	fi

	if test $ol_with_threads = nt ; then
		AC_MSG_ERROR([could not locate NT Threads])
	fi
fi

if test $ol_with_threads = auto -o $ol_with_threads = yes \
	-o $ol_with_threads = posix ; then

	AC_CHECK_HEADERS(pthread.h)

	if test $ac_cv_header_pthread_h = yes ; then
		OL_POSIX_THREAD_VERSION

		if test $ol_cv_pthread_version != 0 ; then
			AC_DEFINE_UNQUOTED(HAVE_PTHREADS,$ol_cv_pthread_version,
				[define to pthreads API spec revision])
		else
			AC_MSG_ERROR([unknown pthread version])
		fi

		# consider threads found
		ol_with_threads=found

		OL_HEADER_LINUX_THREADS
		OL_HEADER_GNU_PTH_PTHREAD_H

		if test $ol_cv_header_gnu_pth_pthread_h = no ; then
			AC_CHECK_HEADERS(sched.h)
		fi

		dnl Now the hard part, how to link?
		dnl
		dnl currently supported checks:
		dnl
		dnl Check for no flags 
		dnl 	pthread_create() in $LIBS
		dnl
		dnl Check special pthread (final) flags
		dnl 	[skipped] pthread_create() with -mt (Solaris) [disabled]
		dnl 	pthread_create() with -kthread (FreeBSD)
		dnl 	pthread_create() with -pthread (FreeBSD/Digital Unix)
		dnl 	pthread_create() with -pthreads (?)
		dnl 	pthread_create() with -mthreads (AIX)
		dnl 	pthread_create() with -thread (?)
		dnl
		dnl Check pthread (final) libraries
		dnl 	pthread_mutex_unlock() in -lpthread -lmach -lexc -lc_r (OSF/1)
		dnl 	pthread_mutex_lock() in -lpthread -lmach -lexc (OSF/1)
		dnl 	[skipped] pthread_mutex_trylock() in -lpthread -lexc (OSF/1)
		dnl 	pthread_join() -Wl,-woff,85 -lpthread (IRIX)
		dnl 	pthread_create() in -lpthread (many)
		dnl 	pthread_create() in -lc_r (FreeBSD)
		dnl
		dnl Check pthread (draft4) flags (depreciated)
		dnl 	pthread_create() with -threads (OSF/1)
		dnl
		dnl Check pthread (draft4) libraries (depreciated)
		dnl 	pthread_mutex_unlock() in -lpthreads -lmach -lexc -lc_r (OSF/1)
		dnl 	pthread_mutex_lock() in -lpthreads -lmach -lexc (OSF/1)
		dnl 	pthread_mutex_trylock() in -lpthreads -lexc (OSF/1)
		dnl 	pthread_create() in -lpthreads (many)
		dnl

		dnl pthread_create in $LIBS
		AC_CACHE_CHECK([for pthread_create in default libraries],
			ol_cv_pthread_create,[
		AC_TRY_RUN(OL_PTHREAD_TEST_PROGRAM,
			[ol_cv_pthread_create=yes],
			[ol_cv_pthread_create=no],
			[AC_TRY_LINK(OL_PTHREAD_TEST_INCLUDES,OL_PTHREAD_TEST_FUNCTION,
				[ol_cv_pthread_create=yes],
				[ol_cv_pthread_create=no])])])

		if test $ol_cv_pthread_create != no ; then
			ol_link_threads=posix
			ol_link_pthreads=""
		fi
		
dnl		OL_PTHREAD_TRY([-mt],		[ol_cv_pthread_mt])
		OL_PTHREAD_TRY([-kthread],	[ol_cv_pthread_kthread])
		OL_PTHREAD_TRY([-pthread],	[ol_cv_pthread_pthread])
		OL_PTHREAD_TRY([-pthreads],	[ol_cv_pthread_pthreads])
		OL_PTHREAD_TRY([-mthreads],	[ol_cv_pthread_mthreads])
		OL_PTHREAD_TRY([-thread],	[ol_cv_pthread_thread])

		OL_PTHREAD_TRY([-lpthread -lmach -lexc -lc_r],
			[ol_cv_pthread_lpthread_lmach_lexc_lc_r])
		OL_PTHREAD_TRY([-lpthread -lmach -lexc],
			[ol_cv_pthread_lpthread_lmach_lexc])
dnl		OL_PTHREAD_TRY([-lpthread -lexc],
dnl			[ol_cv_pthread_lpthread_lexc])

		OL_PTHREAD_TRY([-lpthread -Wl,-woff,85],
			[ol_cv_pthread_lib_lpthread_woff])

		OL_PTHREAD_TRY([-lpthread],	[ol_cv_pthread_lpthread])
		OL_PTHREAD_TRY([-lc_r],		[ol_cv_pthread_lc_r])

		OL_PTHREAD_TRY([-threads],	[ol_cv_pthread_threads])

		OL_PTHREAD_TRY([-lpthreads -lmach -lexc -lc_r],
			[ol_cv_pthread_lpthreads_lmach_lexc_lc_r])
		OL_PTHREAD_TRY([-lpthreads -lmach -lexc],
			[ol_cv_pthread_lpthreads_lmach_lexc])
		OL_PTHREAD_TRY([-lpthreads -lexc],
			[ol_cv_pthread_lpthreads_lexc])

		OL_PTHREAD_TRY([-lpthreads],[ol_cv_pthread_lib_lpthreads])

		if test $ol_link_threads != no ; then
			LTHREAD_LIBS="$LTHREAD_LIBS $ol_link_pthreads"

			dnl save flags
			save_CPPFLAGS="$CPPFLAGS"
			save_LIBS="$LIBS"
			LIBS="$LTHREAD_LIBS $LIBS"

			dnl All POSIX Thread (final) implementations should have
			dnl sched_yield instead of pthread yield.
			dnl check for both, and thr_yield for Solaris
			AC_CHECK_FUNCS(sched_yield pthread_yield thr_yield)

			if test $ac_cv_func_sched_yield = no -a \
				$ac_cv_func_pthread_yield = no -a \
				$ac_cv_func_thr_yield = no ; then
				dnl Digital UNIX has sched_yield() in -lrt
				AC_CHECK_LIB(rt, sched_yield,
					[LTHREAD_LIBS="$LTHREAD_LIBS -lrt"
					AC_DEFINE(HAVE_SCHED_YIELD,1,
						[Define if you have the sched_yield function.])
					ac_cv_func_sched_yield=yes],
					[ac_cv_func_sched_yield=no])
			fi
			if test $ac_cv_func_sched_yield = no -a \
				$ac_cv_func_pthread_yield = no -a \
				"$ac_cv_func_thr_yield" = no ; then
				AC_MSG_WARN([could not locate sched_yield() or pthread_yield()])
			fi

			dnl Check functions for compatibility
			AC_CHECK_FUNCS(pthread_kill pthread_rwlock_destroy)

			dnl Check for pthread_detach with <pthread.h> inclusion
			dnl as it's symbol may have been mangled.
			AC_CACHE_CHECK([for pthread_detach with <pthread.h>],
				[ol_cv_func_pthread_detach], [
				dnl save the flags
				AC_TRY_LINK([
#include <pthread.h>
#ifndef NULL
#define NULL (void*)0
#endif
],
					[pthread_detach(NULL);],
					[ol_cv_func_pthread_detach=yes],
					[ol_cv_func_pthread_detach=no])
			])

			if test $ol_cv_func_pthread_detach = no ; then
				AC_MSG_ERROR([could not locate pthread_detach()])
			fi

			AC_DEFINE(HAVE_PTHREAD_DETACH,1,
				[define if you have pthread_detach function])

			dnl Check for setconcurreny functions
			AC_CHECK_FUNCS(	\
				pthread_setconcurrency \
				pthread_getconcurrency \
				thr_setconcurrency \
				thr_getconcurrency \
			)

			OL_SYS_LINUX_THREADS
			OL_LINUX_THREADS

			if test $ol_cv_linux_threads = error; then
				AC_MSG_ERROR([LinuxThreads header/library mismatch]);
			fi

			AC_CACHE_CHECK([if pthread_create() works],
				ol_cv_pthread_create_works,[
			AC_TRY_RUN(OL_PTHREAD_TEST_PROGRAM,
				[ol_cv_pthread_create_works=yes],
				[ol_cv_pthread_create_works=no],
				[dnl assume yes
				ol_cv_pthread_create_works=yes])])

			if test $ol_cv_pthread_create_works = no ; then
				AC_MSG_ERROR([pthread_create is not usable, check environment settings])
			fi

			dnl Check if select causes an yield
			if test $ol_with_yielding_select = auto ; then
				AC_CACHE_CHECK([if select yields when using pthreads],
					ol_cv_pthread_select_yields,[
				AC_TRY_RUN([
#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>
#include <pthread.h>
#ifndef NULL
#define NULL (void*) 0
#endif

static int fildes[2];

static void *task(p)
	void *p;
{
	int i;
	struct timeval tv;

	fd_set rfds;

	tv.tv_sec=10;
	tv.tv_usec=0;

	FD_ZERO(&rfds);
	FD_SET(fildes[0], &rfds);

	/* we're not interested in any fds */
	i = select(FD_SETSIZE, &rfds, NULL, NULL, &tv);

	if(i < 0) {
		perror("select");
		exit(10);
	}

	exit(0); /* if we exit here, the select blocked the whole process */
}

int main(argc, argv)
	int argc;
	char **argv;
{
	pthread_t t;

	/* create a pipe to select */
	if(pipe(&fildes[0])) {
		perror("select");
		exit(1);
	}

#ifdef HAVE_PTHREAD_SETCONCURRENCY
	(void) pthread_setconcurrency(2);
#else
#ifdef HAVE_THR_SETCONCURRENCY
	/* Set Solaris LWP concurrency to 2 */
	thr_setconcurrency(2);
#endif
#endif

#if HAVE_PTHREADS < 6
	pthread_create(&t, pthread_attr_default, task, NULL);
#else
	pthread_create(&t, NULL, task, NULL);
#endif

	/* make sure task runs first */
#if HAVE_THR_YIELD
	thr_yield();
#elif defined( HAVE_SCHED_YIELD )
	sched_yield();
#elif defined( HAVE_PTHREAD_YIELD )
	pthread_yield();
#endif

	exit(2);
}],
				[ol_cv_pthread_select_yields=no],
				[ol_cv_pthread_select_yields=yes],
				[ol_cv_pthread_select_yields=cross])])

				if test $ol_cv_pthread_select_yields = cross ; then
					AC_MSG_ERROR([crossing compiling: use --with-yielding_select=yes|no|manual])
				fi

				if test $ol_cv_pthread_select_yields = yes ; then
					ol_with_yielding_select=yes
				fi
			fi

			dnl restore flags
			CPPFLAGS="$save_CPPFLAGS"
			LIBS="$save_LIBS"
		else
			AC_MSG_ERROR([could not locate usable POSIX Threads])
		fi
	fi

	if test $ol_with_threads = posix ; then
		AC_MSG_ERROR([could not locate POSIX Threads])
	fi
fi

if test $ol_with_threads = auto -o $ol_with_threads = yes \
	-o $ol_with_threads = mach ; then

	dnl check for Mach CThreads
	AC_CHECK_HEADERS(mach/cthreads.h cthreads.h)
	if test $ac_cv_header_mach_cthreads_h = yes ; then
		ol_with_threads=found

		dnl check for cthreads support in current $LIBS
		AC_CHECK_FUNC(cthread_fork,[ol_link_threads=yes])

		if test $ol_link_threads = no ; then
			dnl try -all_load
			dnl this test needs work
			AC_CACHE_CHECK([for cthread_fork with -all_load],
				[ol_cv_cthread_all_load], [
				dnl save the flags
				save_LIBS="$LIBS"
				LIBS="-all_load $LIBS"
				AC_TRY_LINK([#include <mach/cthreads.h>],[
					cthread_fork((void *)0, (void *)0);
					], ol_cv_cthread_all_load=yes, ol_cv_cthread_all_load=no)
				dnl restore the LIBS
				LIBS="$save_LIBS"
			])

			if test $ol_cv_cthread_all_load = yes ; then
				LTHREAD_LIBS="$LTHREAD_LIBS -all_load"
				ol_link_threads=mach
				ol_with_threads=found
			fi
		fi

	elif test $ac_cv_header_cthreads_h = yes ; then
		dnl Hurd variant of Mach Cthreads
		dnl uses <cthreads.h> and -lthreads

		ol_with_threads=found
 
		dnl save the flags
		save_LIBS="$LIBS"
		LIBS="$LIBS -lthreads"
		AC_CHECK_FUNC(cthread_fork,[ol_link_threads=yes])
		LIBS="$save_LIBS"

		if test $ol_link_threads = yes ; then
			LTHREAD_LIBS="-lthreads"
			ol_link_threads=mach
			ol_with_threads=found
		else
			AC_MSG_ERROR([could not link with Mach CThreads])
		fi

	elif test $ol_with_threads = mach ; then
		AC_MSG_ERROR([could not locate Mach CThreads])
	fi

	if test $ol_link_threads = mach ; then
		AC_DEFINE(HAVE_MACH_CTHREADS,1,
			[define if you have Mach Cthreads])
	elif test $ol_with_threads = found ; then
		AC_MSG_ERROR([could not link with Mach CThreads])
	fi
fi

if test $ol_with_threads = auto -o $ol_with_threads = yes \
	-o $ol_with_threads = pth ; then

	AC_CHECK_HEADERS(pth.h)

	if test $ac_cv_header_pth_h = yes ; then
		AC_CHECK_LIB(pth, pth_version, [have_pth=yes], [have_pth=no])

		if test $have_pth = yes ; then
			AC_DEFINE(HAVE_GNU_PTH,1,[if you have GNU Pth])
			LTHREAD_LIBS="$LTHREAD_LIBS -lpth"
			ol_link_threads=pth
			ol_with_threads=found

			if test $ol_with_yielding_select = auto ; then
				ol_with_yielding_select=yes
			fi
		fi
	fi
fi

if test $ol_with_threads = auto -o $ol_with_threads = yes \
	-o $ol_with_threads = lwp ; then

	dnl check for SunOS5 LWP
	AC_CHECK_HEADERS(thread.h synch.h)
	if test $ac_cv_header_thread_h = yes -a $ac_cv_header_synch_h = yes ; then
		AC_CHECK_LIB(thread, thr_create, [have_thr=yes], [have_thr=no])

		if test $have_thr = yes ; then
			AC_DEFINE(HAVE_THR,1,
				[if you have Solaris LWP (thr) package])
			LTHREAD_LIBS="$LTHREAD_LIBS -lthread"
			ol_link_threads=thr

			if test $ol_with_yielding_select = auto ; then
				ol_with_yielding_select=yes
			fi

			dnl Check for setconcurreny functions
			AC_CHECK_FUNCS(	\
				thr_setconcurrency \
				thr_getconcurrency \
			)
		fi
	fi

	dnl check for SunOS4 LWP
	AC_CHECK_HEADERS(lwp/lwp.h)
	if test $ac_cv_header_lwp_lwp_h = yes ; then
		AC_CHECK_LIB(lwp, lwp_create, [have_lwp=yes], [have_lwp=no])

		if test $have_lwp = yes ; then
			AC_DEFINE(HAVE_LWP,1,
				[if you have SunOS LWP package])
			LTHREAD_LIBS="$LTHREAD_LIBS -llwp"
			ol_link_threads=lwp

			if test $ol_with_yielding_select = auto ; then
				ol_with_yielding_select=no
			fi
		fi
	fi
fi

if test $ol_with_yielding_select = yes ; then
	AC_DEFINE(HAVE_YIELDING_SELECT,1,
		[define if select implicitly yields])
fi

if test $ol_with_threads = manual ; then
	dnl User thinks he can manually configure threads.
	ol_link_threads=yes

	AC_MSG_WARN([thread defines and link options must be set manually])

	AC_CHECK_HEADERS(pthread.h sched.h)
	AC_CHECK_FUNCS(sched_yield pthread_yield)
	OL_HEADER_LINUX_THREADS

	AC_CHECK_HEADERS(mach/cthreads.h)
	AC_CHECK_HEADERS(lwp/lwp.h)
	AC_CHECK_HEADERS(thread.h synch.h)
fi

if test $ol_link_threads != no -a $ol_link_threads != nt ; then  
	dnl needed to get reentrant/threadsafe versions
	dnl
	AC_DEFINE(REENTRANT,1)
	AC_DEFINE(_REENTRANT,1)
	AC_DEFINE(THREAD_SAFE,1)
	AC_DEFINE(_THREAD_SAFE,1)
	AC_DEFINE(THREADSAFE,1)
	AC_DEFINE(_THREADSAFE,1)
	AC_DEFINE(_SGI_MP_SOURCE,1)

	dnl The errno declaration may dependent upon _REENTRANT.
	dnl If it does, we must link with thread support.
	AC_CACHE_CHECK([for thread specific errno],
		[ol_cv_errno_thread_specific], [
		AC_TRY_LINK([#include <errno.h>], [errno = 0;],
			[ol_cv_errno_thread_specific=yes],
			[ol_cv_errno_thread_specific=no])
	])

	dnl The h_errno declaration may dependent upon _REENTRANT.
	dnl If it does, we must link with thread support.
	AC_CACHE_CHECK([for thread specific h_errno],
		[ol_cv_h_errno_thread_specific], [
		AC_TRY_LINK([#include <netdb.h>], [h_errno = 0;],
			[ol_cv_h_errno_thread_specific=yes],
			[ol_cv_h_errno_thread_specific=no])
	])

	if test $ol_cv_errno_thread_specific != yes \
		-o $ol_cv_h_errno_thread_specific != yes ; then
		LIBS="$LTHREAD_LIBS $LIBS"
		LTHREAD_LIBS=""
	fi

dnl When in thread environment, use 
dnl		#if defined( HAVE_REENTRANT_FUNCTIONS ) || defined( HAVE_FUNC_R )
dnl			func_r(...);
dnl		#else
dnl		#	if defined( HAVE_THREADS ) 
dnl				/* lock */
dnl		#	endif
dnl				func(...);
dnl		#	if defined( HAVE_THREADS ) 
dnl				/* unlock */
dnl		#	endif
dnl		#endif
dnl
dnl HAVE_REENTRANT_FUNCTIONS is derived from:
dnl		_POSIX_REENTRANT_FUNCTIONS
dnl		_POSIX_THREAD_SAFE_FUNCTIONS
dnl		_POSIX_THREADSAFE_FUNCTIONS
dnl
dnl		and is currently defined in <ldap_pvt_thread.h>
dnl
dnl HAVE_THREADS is defined by <ldap_pvt_thread.h> iff -UNO_THREADS
dnl 
dnl libldap/*.c should only include <ldap_pvt_thread.h> iff
dnl LDAP_R_COMPILE is defined.  ie:
dnl		#ifdef LDAP_R_COMPILE
dnl		#	include <ldap_pvt_thread.h>
dnl		#endif
dnl
dnl LDAP_R_COMPILE is defined by libldap_r/Makefile.in
dnl specifically for compiling the threadsafe version of
dnl	the ldap library (-lldap_r).
dnl		
dnl	dnl check for reentrant/threadsafe functions
dnl	dnl
dnl	dnl note: these should only be used when linking
dnl	dnl		with $LTHREAD_LIBS
dnl	dnl
dnl	save_CPPFLAGS="$CPPFLAGS"
dnl	save_LIBS="$LIBS"
dnl	LIBS="$LTHREAD_LIBS $LIBS"
dnl	AC_CHECK_FUNCS(	\
dnl		gmtime_r \
dnl		gethostbyaddr_r gethostbyname_r \
dnl		feof_unlocked unlocked_feof \
dnl		putc_unlocked unlocked_putc \
dnl		flockfile ftrylockfile \
dnl	)
dnl	CPPFLAGS="$save_CPPFLAGS"
dnl	LIBS="$save_LIBS"
fi  

if test $ol_link_threads = no ; then
	if test $ol_with_threads = yes ; then
		AC_MSG_ERROR([no suitable thread support])
	fi

	if test $ol_with_threads = auto ; then
		AC_MSG_WARN([no suitable thread support, disabling threads])
		ol_with_threads=no
	fi

	AC_DEFINE(NO_THREADS,1,
		[define if you have (or want) no threads])
	LTHREAD_LIBS=""
fi

if test $ol_link_threads != no ; then
	AC_DEFINE(LDAP_API_FEATURE_X_OPENLDAP_THREAD_SAFE,1)
fi

dnl ----------------------------------------------------------------
dnl Tests for reentrant functions necessary to build -lldap_r
AC_CHECK_FUNCS(		\
	ctime_r			\
	gethostbyname_r	gethostbyaddr_r \
)

if test "$ac_cv_func_ctime_r" = no ; then
	ol_cv_func_ctime_r_nargs=0
else
	OL_FUNC_CTIME_R_NARGS
dnl	OL_FUNC_CTIME_R_TYPE
fi

if test "$ac_cv_func_gethostbyname_r" = yes ; then
 	OL_FUNC_GETHOSTBYNAME_R_NARGS
else
 	ol_cv_func_gethostbyname_r_nargs=0
fi
 
if test "$ac_cv_func_gethostbyaddr_r" = yes ; then
 	OL_FUNC_GETHOSTBYADDR_R_NARGS
else
 	ol_cv_func_gethostbyaddr_r_nargs=0
fi

dnl ----------------------------------------------------------------
ol_link_ldbm=no 

if test $ol_with_ldbm_api = auto \
	-o $ol_with_ldbm_api = berkeley \
	-o $ol_with_ldbm_api = bcompat ; then

	if test $ol_with_ldbm_api = bcompat; then \
		OL_BERKELEY_COMPAT_DB
	else
		OL_BERKELEY_DB
	fi

	if test $ol_cv_berkeley_db != no ; then
		AC_DEFINE(HAVE_BERKELEY_DB,1,
			[define this if Berkeley DB is available])

		ol_link_ldbm=berkeley
		ol_with_ldbm_api=berkeley

		if test $ol_with_ldbm_type = hash ; then
			AC_DEFINE(LDBM_USE_DBHASH,1,
				[define this to use DBHASH w/ LDBM backend])
		else
			AC_DEFINE(LDBM_USE_DBBTREE,1,
				[define this to use DBBTREE w/ LDBM backend])
		fi

		dnl $ol_cv_lib_db should be yes or -ldb
		dnl (it could be no, but that would be an error
		if test $ol_cv_lib_db != yes ; then
			LDBM_LIBS="$LDBM_LIBS $ol_cv_lib_db"
		fi
	fi
fi

if test $ol_enable_bdb = yes -a $ol_link_ldbm != berkeley ; then
	AC_MSG_ERROR(BDB: BerkeleyDB not available)
elif test $ol_enable_bdb != no -a $ol_link_ldbm = berkeley ; then
	OL_BDB_COMPAT

	if test $ol_cv_bdb_compat = yes ; then
		ol_enable_bdb=yes
	elif test $ol_enable_bdb = yes ; then
		AC_MSG_ERROR(BDB: BerkeleyDB version incompatible)
	else
		ol_enable_bdb=no
	fi
fi
if test $ol_enable_hdb = yes -a $ol_link_ldbm != berkeley ; then
	AC_MSG_ERROR(HDB: BerkeleyDB not available)
fi

if test $ol_link_ldbm = no -a $ol_with_ldbm_type = btree ; then
	AC_MSG_WARN(Could not find LDBM with BTREE support)
	ol_with_ldbm_api=none
fi

if test $ol_with_ldbm_api = auto -o $ol_with_ldbm_api = mdbm ; then
	OL_MDBM

	if test $ol_cv_mdbm = yes ; then
		ol_link_ldbm=mdbm
		ol_with_ldbm_api=mdbm
		if test $ol_cv_lib_mdbm != yes ; then
			LDBM_LIBS="$LDBM_LIBS $ol_cv_lib_mdbm"
		fi
	fi
fi

if test $ol_with_ldbm_api = auto -o $ol_with_ldbm_api = gdbm ; then