Allow only one running instance of critical tasks

1 files changed, 17 insertions, 6 deletions

diff --git a/src/main/java/org/openslx/taskmanager/tasks/CompileIPxe.java b/src/main/java/org/openslx/taskmanager/tasks/CompileIPxe.java
index 70ae195..f3ebc82 100644
--- a/src/main/java/org/openslx/taskmanager/tasks/CompileIPxe.java
+++ b/src/main/java/org/openslx/taskmanager/tasks/CompileIPxe.java
@@ -4,6 +4,7 @@ import java.io.File;
 import java.io.IOException;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.commons.io.FileUtils;
 import org.apache.log4j.Logger;
@@ -29,6 +30,8 @@ public class CompileIPxe extends AbstractTask
 
 	private Output status = new Output();
 
+	private static AtomicBoolean isRunning = new AtomicBoolean();
+
 	@Override
 	protected boolean initTask()
 	{
@@ -49,12 +52,20 @@ public class CompileIPxe extends AbstractTask
 	@Override
 	protected boolean execute()
 	{
-		boolean ret = true;
-		if ( !updateMenu() )
-			ret = false;
-		if ( !updateIpxe() )
-			ret = false;
-		return ret;
+		if (!isRunning.compareAndSet( false, true )) {
+			status.error = "Another operation is already in progress.";
+			return false;
+		}
+		try {
+			boolean ret = true;
+			if ( !updateMenu() )
+				ret = false;
+			if ( !updateIpxe() )
+				ret = false;
+			return ret;
+		} finally {
+			isRunning.set( false );
+		}
 	}
 
 	private boolean updateMenu()