From ac5050f0f706b364c89b79975b2cbf309259f4fa Mon Sep 17 00:00:00 2001
From: Michael Jumper <mike.jumper@guac-dev.org>
Date: Wed, 14 Aug 2013 17:44:41 -0700
Subject: [PATCH] Prevent accidental addition of cycles.

---
 guacamole/src/main/webapp/scripts/admin-ui.js | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/guacamole/src/main/webapp/scripts/admin-ui.js b/guacamole/src/main/webapp/scripts/admin-ui.js
index 8c08bb18c..48a4ae90e 100644
--- a/guacamole/src/main/webapp/scripts/admin-ui.js
+++ b/guacamole/src/main/webapp/scripts/admin-ui.js
@@ -1022,9 +1022,22 @@ GuacAdmin.ConnectionGroupEditor = function(group, parameters) {
         document.body.appendChild(group_select.getElement());
 
         // Update location when chosen
-        group_select.onselect = function(group) {
-            location_value = group;
-            location.textContent = group.name;
+        group_select.onselect = function(selected_group) {
+
+            // Prevent selecting a situation that would produce a cycle
+            var current = selected_group;
+            while (current !== null) {
+                
+                if (current.id === group.id) {
+                    alert("Cannot move a group into a subgroup of itself.");
+                    return;
+                }
+                
+                current = current.parent;
+            }
+
+            location_value = selected_group;
+            location.textContent = selected_group.name;
         };
 
     };