Raise an exception if we cannot find a matching principal.

git-svn-id: https://svn.calendarserver.org/repository/calendarserver/PyKerberos/trunk@1541 e27351fd-9f3e-4f54-a53b-843176b1656c

src/kerberosgss.c

@@ -90,6 +90,12 @@ char* server_principal_details(const char* service, const char* hostname)
       krb5_free_keytab_entry_contents(kcontext, &entry);
     }
 
+    if (result == NULL)
+    {
+		PyErr_SetObject(KrbException_class, Py_BuildValue("((s:i))",
+				"Principal not found in keytab", -1));
+    }
+
 end:
 	if (cursor)
 		krb5_kt_end_seq_get(kcontext, kt, &cursor);