Remove questions from ipaserver.dsinstance

Let's assume that all ipaserver.dsinstance could be used
somewhere where asking questions on stdout/stdin is not
approriate and re-factor the code to be suitable in
those situations too.

i.e. make check_existing_installation() return a list of
server IDs and make check_ports() return an (unsecure,
secure) tuple indication which ports are in use.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>

diff -r 453884e0f13b ipa-server/ipa-install/ipa-server-install
--- a/ipa-server/ipa-install/ipa-server-install	Thu Jan 17 16:36:05 2008 -0500
+++ b/ipa-server/ipa-install/ipa-server-install	Sat Jan 19 17:50:04 2008 +0000
@@ -247,6 +247,33 @@ def read_admin_password():
     admin_password = read_password("IPA admin")
     return admin_password
 
+def check_dirsrv():
+    serverids = ipaserver.dsinstance.check_existing_installation()
+    if serverids:
+        print ""
+        print "An existing Directory Server has been detected."
+        yesno = raw_input("Do you wish to remove it and create a new one? [no]: ")
+        if not yesno or yesno.lower()[0] != "y":
+            sys.exit(1)
+
+        try:
+            service.stop("dirsrv")
+        except:
+            pass
+
+        for serverid in serverids:
+            ipaserver.dsinstance.erase_ds_instance_data(serverid)
+
+    (ds_unsecure, ds_secure) = ipaserver.dsinstance.check_ports()
+    if not ds_unsecure or not ds_secure:
+        print "IPA requires ports 389 and 636 for the Directory Server."
+        print "These are currently in use:"
+        if not ds_unsecure:
+            print "\t389"
+        if not ds_secure:
+            print "\t636"
+        sys.exit(1)
+
 def uninstall():
     ipaserver.ntpinstance.NTPInstance().uninstall()
     ipaserver.bindinstance.BindInstance().uninstall()
@@ -282,9 +309,7 @@ def main():
     print "To accept the default shown in brackets, press the Enter key."
     print ""
 
-    ipaserver.dsinstance.check_existing_installation()
-    ipaserver.dsinstance.check_ports()
-
+    check_dirsrv()
 
     ds_user = ""
     realm_name = ""
diff -r 453884e0f13b ipa-server/ipaserver/dsinstance.py
--- a/ipa-server/ipaserver/dsinstance.py	Thu Jan 17 16:36:05 2008 -0500
+++ b/ipa-server/ipaserver/dsinstance.py	Sat Jan 19 17:50:04 2008 +0000
@@ -72,34 +72,18 @@ def check_existing_installation():
 def check_existing_installation():
     dirs = glob.glob("/etc/dirsrv/slapd-*")
     if not dirs:
-        return
-    print ""
-    print "An existing Directory Server has been detected."
-    yesno = raw_input("Do you wish to remove it and create a new one? [no]: ")
-    if not yesno or yesno.lower()[0] != "y":
-        sys.exit(1)
-
-    try:
-        service.stop("dirsrv")
-    except:
-        pass
+        return []
+
+    serverids = []
     for d in dirs:
-        serverid = os.path.basename(d).split("slapd-", 1)[1]
-        if serverid:
-            erase_ds_instance_data(serverid)
+        serverids.append(os.path.basename(d).split("slapd-", 1)[1])
+
+    return serverids
 
 def check_ports():
     ds_unsecure = installutils.port_available(389)
     ds_secure = installutils.port_available(636)
-    if not ds_unsecure or not ds_secure:
-        print "IPA requires ports 389 and 636 for the Directory Server."
-        print "These are currently in use:"
-        if not ds_unsecure:
-            print "\t389"
-        if not ds_secure:
-            print "\t636"
-        sys.exit(1)
-
+    return (ds_unsecure, ds_secure)
 
 INF_TEMPLATE = """
 [General]