import unset CDPATH and improved res_search detection from devel

CHANGES

@@ -13,7 +13,9 @@ Changes included in OpenLDAP 1.2.11 Release Engineering
 	Raise MAXDBCACHE to 128 (ITS#512)
 	Fixed slapd client_addr crash (ITS#579)
 	Build Environment
+		Update res_search detection
 		Detect and use getpassphrase() and getpass()
+		Unset CDPATH
 		Change GNU Pth to enable soft syscalls
 		Changed RCPT cmds symbol to avoid link conflict (ITS#526)
 		Changed LDBM directory to $localstatedir/openldap-ldbm

configure.in

@@ -10,9 +10,18 @@ dnl
 dnl Disable config.cache!
 define([AC_CACHE_LOAD], )dnl
 define([AC_CACHE_SAVE], )dnl
-
 dnl Configure.in for OpenLDAP
 AC_INIT(include/ldap.h)dnl
+
+# set unset (borrowed from autoconf 2.14a)
+if (unset FOO) >/dev/null 2>&1; then
+  ol_unset=unset
+else
+  ol_unset=false
+fi
+# unset CDPATH
+$ol_unset CDPATH || test "${CDPATH+set}" != set || CDPATH=: && export CDPATH
+
 AC_CONFIG_AUX_DIR(build)dnl
 AM_INIT_AUTOMAKE(openldap,[1.2], [no ac_define])dnl
 
@@ -290,14 +299,18 @@ dnl Check for resolver routines
 AC_CHECK_FUNCS(res_search)
 if test $ac_cv_func_res_search = "no" ; then 
 	AC_CHECK_LIB(bind, res_search)
-	if test "$ac_cv_lib_bind_res_search" = "yes" ; then
-		AC_DEFINE(HAVE_RES_SEARCH,1)
-	else
-		AC_CHECK_LIB(resolv, res_search)
-		if test "$ac_cv_lib_resolv_res_search" = "yes" ; then
-			AC_DEFINE(HAVE_RES_SEARCH,1)
-		fi
-	fi
+	ac_cv_func_res_search=$ac_cv_lib_bind_res_search
+fi
+if test $ac_cv_func_res_search = "no" ; then 
+	AC_CHECK_LIB(bind, __res_search)
+	ac_cv_func_res_search=$ac_cv_lib_bind_res___search
+fi
+if test $ac_cv_func_res_search = "no" ; then 
+	AC_CHECK_LIB(resolv, res_search)
+	ac_cv_func_res_search=$ac_cv_lib_resolv_res_search
+fi
+if test "$ac_cv_func_res_search" = "yes" ; then
+	AC_DEFINE(HAVE_RES_SEARCH,1)
 fi
 
 dnl HP-UX requires -lV3