* Streaming: Atomics for close/reset send/receive

so we only do things once. (Ticket #1041)

apps/streaming/java/src/net/i2p/client/streaming/Connection.java

@@ -6,6 +6,7 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 
@@ -32,9 +33,8 @@ class Connection {
     private long _receiveStreamId;
     private volatile long _lastSendTime;
     private final AtomicLong _lastSendId;
-    private boolean _resetReceived;
-    private boolean _resetSent;
-    private long _resetSentOn;
+    private final AtomicBoolean _resetReceived = new AtomicBoolean();
+    private final AtomicLong _resetSentOn = new AtomicLong();
     private volatile boolean _connected;
     private boolean _hardDisconnected;
     private final MessageInputStream _inputStream;
@@ -43,8 +43,8 @@ class Connection {
     private volatile long _nextSendTime;
     private long _ackedPackets;
     private final long _createdOn;
-    private long _closeSentOn;
-    private long _closeReceivedOn;
+    private final AtomicLong _closeSentOn = new AtomicLong();
+    private final AtomicLong _closeReceivedOn = new AtomicLong();
     private int _unackedPacketsReceived;
     private long _congestionWindowEnd;
     private volatile long _highestAckedThrough;
@@ -130,8 +130,6 @@ class Connection {
         _lastSendId = new AtomicLong(-1);
         _nextSendTime = -1;
         _createdOn = _context.clock().now();
-        _closeSentOn = -1;
-        _closeReceivedOn = -1;
         _congestionWindowEnd = _options.getWindowSize()-1;
         _highestAckedThrough = -1;
         _lastCongestionSeenAt = MAX_WINDOW_SIZE*2; // lets allow it to grow
@@ -142,7 +140,6 @@ class Connection {
         _activityTimer = new ActivityTimer();
         _ackSinceCongestion = true;
         _connectLock = new Object();
-        _resetSentOn = -1;
         _connectionEvent = new ConEvent();
         _randomWait = _context.random().nextInt(10*1000); // just do this once to reduce usage
         // all createRateStats in ConnectionManager
@@ -155,9 +152,10 @@ class Connection {
     }
     
     void closeReceived() {
-        setCloseReceivedOn(_context.clock().now());
-        _inputStream.closeReceived();
-        synchronized (_connectLock) { _connectLock.notifyAll(); }
+        if (setCloseReceivedOn(_context.clock().now())) {
+            _inputStream.closeReceived();
+            synchronized (_connectLock) { _connectLock.notifyAll(); }
+        }
     }
     
     /**
@@ -284,11 +282,9 @@ class Connection {
     void sendReset() {
         scheduleDisconnectEvent();
         long now = _context.clock().now();
-        if (_resetSentOn + 10*1000 > now) return; // don't send resets too fast
-        if (_resetReceived) return;
-        _resetSent = true;
-        if (_resetSentOn <= 0)
-            _resetSentOn = now;
+        if (_resetSentOn.get() + 10*1000 > now) return; // don't send resets too fast
+        if (_resetReceived.get()) return;
+        _resetSentOn.compareAndSet(0, now);
         if ( (_remotePeer == null) || (_sendStreamId <= 0) ) return;
         PacketLocal reply = new PacketLocal(_context, _remotePeer);
         reply.setFlag(Packet.FLAG_RESET);
@@ -534,15 +530,17 @@ class Connection {
     }
     
     void resetReceived() {
+        if (!_resetReceived.compareAndSet(false, true))
+            return;
         scheduleDisconnectEvent();
-        _resetReceived = true;
         IOException ioe = new IOException("Reset received");
         _outputStream.streamErrorOccurred(ioe);
         _inputStream.streamErrorOccurred(ioe);
         _connectionError = "Connection reset";
         synchronized (_connectLock) { _connectLock.notifyAll(); }
     }
-    public boolean getResetReceived() { return _resetReceived; }
+
+    public boolean getResetReceived() { return _resetReceived.get(); }
     
     public void setInbound() { _isInbound = true; }
     public boolean isInbound() { return _isInbound; }
@@ -556,8 +554,10 @@ class Connection {
     public boolean getIsConnected() { return _connected; }
 
     public boolean getHardDisconnected() { return _hardDisconnected; }
-    public boolean getResetSent() { return _resetSent; }
-    public long getResetSentOn() { return _resetSentOn; }
+    public boolean getResetSent() { return _resetSentOn.get() > 0; }
+
+    /** @return 0 if not sent */
+    public long getResetSentOn() { return _resetSentOn.get(); }
 
     /** @return 0 if not scheduled */
     public long getDisconnectScheduledOn() { return _disconnectScheduledOn.get(); }
@@ -750,10 +750,11 @@ class Connection {
     public void setConnectionError(String err) { _connectionError = err; }
     
     public long getLifetime() { 
-        if (_closeSentOn <= 0)
+        long cso = _closeSentOn.get();
+        if (cso <= 0)
             return _context.clock().now() - _createdOn; 
         else
-            return _closeSentOn - _createdOn;
+            return cso - _createdOn;
     }
     
     public ConnectionPacketHandler getPacketHandler() { return _handler; }
@@ -809,16 +810,27 @@ class Connection {
      */
     public long getAckedPackets() { return _ackedPackets; }
     public long getCreatedOn() { return _createdOn; }
-    public long getCloseSentOn() { return _closeSentOn; }
+
+    /** @return 0 if not sent */
+    public long getCloseSentOn() { return _closeSentOn.get(); }
+
     public void setCloseSentOn(long when) { 
-        _closeSentOn = when;
-        scheduleDisconnectEvent();
+        if (_closeSentOn.compareAndSet(0, when))
+            scheduleDisconnectEvent();
+    }
+
+    /** @return 0 if not received */
+    public long getCloseReceivedOn() { return _closeReceivedOn.get(); }
+
+    /**
+     *  @return true if the first close received, false otherwise
+     */
+    public boolean setCloseReceivedOn(long when) {
+        return _closeReceivedOn.compareAndSet(0, when);
     }
-    public long getCloseReceivedOn() { return _closeReceivedOn; }
-    public void setCloseReceivedOn(long when) { _closeReceivedOn = when; }
 
     public void updateShareOpts() {
-        if (_closeSentOn > 0 && !_updatedShareOpts) {
+        if (_closeSentOn.get() > 0 && !_updatedShareOpts) {
             _connectionManager.updateShareOpts(this);
             _updatedShareOpts = true;
         }
@@ -981,7 +993,7 @@ class Connection {
                         _log.warn("Inactivity timer expired, not doing anything");
                     break;
                 case ConnectionOptions.INACTIVITY_ACTION_SEND:
-                    if (_closeSentOn <= 0 && _closeReceivedOn <= 0) {
+                    if (_closeSentOn.get() <= 0 && _closeReceivedOn.get() <= 0) {
                         if (_log.shouldLog(Log.WARN))
                             _log.warn("Sending some data due to inactivity");
                         _receiver.send(null, 0, 0, true);
@@ -1156,8 +1168,8 @@ class Connection {
             if (_packet.getAckTime() > 0) 
                 return false;
             
-            if (_resetSent || _resetReceived || !_connected) {
-                if(_log.shouldLog(Log.WARN) && (!_resetSent) && (!_resetReceived))
+            if (_resetSentOn.get() > 0 || _resetReceived.get() || !_connected) {
+                if(_log.shouldLog(Log.WARN) && (_resetSentOn.get() <= 0) && (!_resetReceived.get()))
                      _log.warn("??? no resets but not connected: " + _packet); // don't think this is possible
                 _packet.cancelled();
                 return false;

apps/streaming/java/src/net/i2p/client/streaming/ConnectionDataReceiver.java

@@ -69,7 +69,7 @@ class ConnectionDataReceiver implements MessageOutputStream.DataReceiver {
         boolean doSend = true;
         if ( (size <= 0) && (con.getLastSendId() >= 0) ) {
             if (con.getOutputStream().getClosed()) {
-                if (con.getCloseSentOn() < 0) {
+                if (con.getCloseSentOn() <= 0) {
                     doSend = true;
                 } else {
                     // closed, no new data, and we've already sent a close packet