Merge pull request #223 from guusdk/OF-883

OF-883: Prevent sending data to known disconnected peers.

src/java/org/jivesoftware/openfire/Connection.java

@@ -144,9 +144,29 @@ public interface Connection {
      *      <li>Call notifyEvent all listeners that the channel is shutting down.
      *      <li>Close the socket.
      * </ul>
+     *
+     * An invocation of this method is equal to invoking {@link #close(boolean)} with a parameter
+     * that is false.
      */
     public void close();
 
+    /**
+     * Close this session including associated socket connection. The order of
+     * events for closing the session is:
+     * <ul>
+     *      <li>Set closing flag to prevent redundant shutdowns.
+     *      <li>Call notifyEvent all listeners that the channel is shutting down.
+     *      <li>Close the socket.
+     * </ul>
+     *
+     * This method takes into account the connection state of the peer. Specifically,
+     * when the peer is known to be in a disconnected state, no data will be sent
+     * (otherwise, this method can trigger the delivery of an end-of-stream signal).
+     *
+     * @param peerIsKnownToBeDisconnected should be set to true when the peer is known to no longer be available.
+     */
+    public void close( boolean peerIsKnownToBeDisconnected );
+
     /**
      * Notification message indicating that the server is being shutdown. Implementors
      * should send a stream error whose condition is system-shutdown before closing

src/java/org/jivesoftware/openfire/net/SocketConnection.java

@@ -442,6 +442,10 @@ public class SocketConnection implements Connection {
     }
 
     public void close() {
+        close( false );
+    }
+
+    public void close( boolean peerIsKnownToBeDisconnected ) {
         boolean wasClosed = false;
         synchronized (this) {
             if (!isClosed()) {
@@ -449,6 +453,8 @@ public class SocketConnection implements Connection {
                     if (session != null) {
                         session.setStatus(Session.STATUS_CLOSED);
                     }
+
+                    if ( !peerIsKnownToBeDisconnected ) {
                         boolean allowedToWrite = false;
                         try {
                             requestWriting();
@@ -472,6 +478,7 @@ public class SocketConnection implements Connection {
                             }
                         }
                     }
+                }
                 catch (Exception e) {
                     Log.error(LocaleUtils.getLocalizedString("admin.error.close")
                             + "\n" + this.toString(), e);

src/java/org/jivesoftware/openfire/net/VirtualConnection.java

@@ -169,6 +169,10 @@ public abstract class VirtualConnection implements Connection {
      * has been closed.
      */
     public void close() {
+        close( false );
+    }
+
+    public void close(boolean peerIsKnownToBeDisconnected) {
         boolean wasClosed = false;
         synchronized (this) {
             if (!isClosed()) {

src/java/org/jivesoftware/openfire/nio/ConnectionHandler.java

@@ -111,7 +111,7 @@ public abstract class ConnectionHandler extends IoHandlerAdapter {
     public void inputClosed( IoSession session ) throws Exception {
         final Connection connection = (Connection) session.getAttribute(CONNECTION);
         if ( connection != null ) {
-            connection.close();
+            connection.close( true );
         }
     }
 

src/java/org/jivesoftware/openfire/nio/NIOConnection.java

@@ -219,7 +219,11 @@ public class NIOConnection implements Connection {
         return backupDeliverer;
     }
 
-    public void close()
+    public void close() {
+        close( false );
+    }
+
+    public void close( boolean peerIsKnownToBeDisconnected )
     {
         boolean notifyClose = false;
         synchronized ( this ) {
@@ -234,6 +238,8 @@ public class NIOConnection implements Connection {
                 if ( state != State.CLOSING )
                 {
                     state = State.CLOSING;
+                    if ( !peerIsKnownToBeDisconnected )
+                    {
                         try
                         {
                             deliverRawText( flashClient ? "</flash:stream>" : "</stream:stream>" );
@@ -243,6 +249,7 @@ public class NIOConnection implements Connection {
                             // Ignore
                         }
                     }
+                }
 
                 // deliverRawText might already have forced the state from Closing to Closed. In that case, there's no need
                 // to invoke the CloseListeners again.