From: Alexandre Montplaisir <alexmonthy@efficios.com>
Date: Thu, 2 Jun 2016 09:22:13 +0000 (-0400)
Subject: Fix: Null-check return value of log4j.Category.getAllAppenders()
X-Git-Url: http://git.efficios.com/?p=deliverable%2Flttng-ust.git;a=commitdiff_plain;h=a548b3c1a329855ad7b2be6937a5a378419fb1b3

Fix: Null-check return value of log4j.Category.getAllAppenders()

Coverity points out this can be null, null-check it to be safe.

If it in indeed null, we must still continue on to verify the
parent loggers.

Signed-off-by: Alexandre Montplaisir <alexmonthy@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/liblttng-ust-java-agent/java/lttng-ust-agent-log4j/org/lttng/ust/agent/log4j/LttngLog4jAgent.java b/liblttng-ust-java-agent/java/lttng-ust-agent-log4j/org/lttng/ust/agent/log4j/LttngLog4jAgent.java
index 7677e68e..157ff3fe 100644
--- a/liblttng-ust-java-agent/java/lttng-ust-agent-log4j/org/lttng/ust/agent/log4j/LttngLog4jAgent.java
+++ b/liblttng-ust-java-agent/java/lttng-ust-agent-log4j/org/lttng/ust/agent/log4j/LttngLog4jAgent.java
@@ -19,6 +19,7 @@ package org.lttng.ust.agent.log4j;
 
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Enumeration;
 import java.util.List;
 import java.util.Set;
 import java.util.TreeSet;
@@ -75,10 +76,12 @@ class LttngLog4jAgent extends AbstractLttngAgent<LttngLogAppender> {
 
 	private static boolean hasLttngAppenderAttached(Category logger) {
 		@SuppressWarnings("unchecked")
-		List<Appender> appenders = Collections.list(logger.getAllAppenders());
-		for (Appender appender : appenders) {
-			if (appender instanceof LttngLogAppender) {
-				return true;
+		Enumeration<Appender> appenders = logger.getAllAppenders();
+		if (appenders != null) {
+			for (Appender appender : Collections.list(appenders)) {
+				if (appender instanceof LttngLogAppender) {
+					return true;
+				}
 			}
 		}