From cdf605b2cd7ccbe40b42810f8aaacb90535496db Mon Sep 17 00:00:00 2001
From: Kelven Yang <kelveny@gmail.com>
Date: Tue, 25 Feb 2014 11:47:51 -0800
Subject: [PATCH] NDC.pop() can return empty string, this causes a loop
 spinning in CallContext.UnregisterAll().

---
 api/src/org/apache/cloudstack/context/CallContext.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/api/src/org/apache/cloudstack/context/CallContext.java b/api/src/org/apache/cloudstack/context/CallContext.java
index f80b921d9c7..22ea55fd869 100644
--- a/api/src/org/apache/cloudstack/context/CallContext.java
+++ b/api/src/org/apache/cloudstack/context/CallContext.java
@@ -239,7 +239,7 @@ public class CallContext {
         String sessionIdOnStack = null;
         String sessionIdPushedToNDC = "ctx-" + UuidUtils.first(contextId);
         while ((sessionIdOnStack = NDC.pop()) != null) {
-            if (sessionIdPushedToNDC.equals(sessionIdOnStack)) {
+            if (sessionIdOnStack.isEmpty() || sessionIdPushedToNDC.equals(sessionIdOnStack)) {
                 break;
             }
             if (s_logger.isTraceEnabled()) {