Original test failed under FreeBSD. Reworked LN_H detection

after LN_S test.  Moved to openldap.m4 and cached result.
Does not yet handle case where LN_H == 'cp' and LN_S == 'ln'.

build/openldap.m4

@@ -55,6 +55,32 @@ dnl AC_VERBOSE(OpenLDAP --with-$1 $ol_with_$1)
 ])dnl
 dnl
 dnl ====================================================================
+dnl
+dnl check if hard links are supported.
+dnl
+AC_DEFUN([OL_PROG_LN_H], [# test for ln hardlink support
+AC_MSG_CHECKING(whether ln works)
+AC_CACHE_VAL(ol_cv_prog_LN_H,
+[rm -f conftest.src conftest.dst
+echo "conftest" > conftest.src
+if ln conftest.src conftest.dst 2>/dev/null
+then
+  ol_cv_prog_LN_H="ln"
+else
+  ol_cv_prog_LN_H="cp"
+fi
+rm -f conftest.src conftest.dst
+])dnl
+LN_H="$ol_cv_prog_LN_H"
+if test "$ol_cv_prog_LN_H" = "ln"; then
+	AC_MSG_RESULT(yes)
+else
+	AC_MSG_RESULT(no)
+fi
+AC_SUBST(LN_H)dnl
+])dnl
+dnl
+dnl ====================================================================
 dnl Check if db.h is Berkeley DB2
 dnl
 dnl defines ol_cv_header_db2 to 'yes' or 'no'

configure.in

@@ -275,28 +275,15 @@ AC_PROG_INSTALL
 dnl The default compiler is cc (NOT gcc)
 CC=${CC-"cc"}
 dnl The default CFLAGS is empty NOT whatever AC_PROG_CC sets.
-CFLAGS=${CFLAGS-""}
+dnl CFLAGS=${CFLAGS-""}
 
 AM_PROG_LIBTOOL
 dnl AC_PROG_MAKE_SET
 
 AC_PROG_AWK
+OL_PROG_LN_H
 AC_PROG_LN_S
 
-dnl Let's test for a way to hardlink (cp or ln)
-AC_MSG_CHECKING(if ln supports hardlinks)
-touch link_test.hard
-if ln link_test.hard link_test.linked > /dev/null 2>&1 ; then
-	LN_H="ln"
-	AC_MSG_RESULT(yes)
-	rm -f link_test.linked
-else
-	LN_H="cp"
-	AC_MSG_RESULT(no...using cp)
-fi
-rm -f link_test.hard
-AC_SUBST(LN_H)
-
 AC_PATH_PROG(SENDMAIL, sendmail, /usr/lib/sendmail,
 	$PATH:/usr/libexec:/usr/lib:/usr/sbin:/usr/etc:/etc)
 AC_PATH_PROG(EDITOR, vi, /usr/ucb/vi, $PATH:/usr/ucb)