Do not reuse buffers as locks

xnio · Sep 11, 2014 · 2bdbbf2 · 2bdbbf2
1 parent 639d2bd
commit 2bdbbf2
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Showing 2 changed files with 18 additions and 12 deletions.
diff --git a/api/src/main/java/org/xnio/channels/FramedMessageChannel.java b/api/src/main/java/org/xnio/channels/FramedMessageChannel.java
@@ -46,6 +46,9 @@ public class FramedMessageChannel extends TranslatingSuspendableChannel<Connecte
     private final Pooled<ByteBuffer> receiveBuffer;
     private final Pooled<ByteBuffer> transmitBuffer;
 
+    private final Object readLock = new Object();
+    private final Object writeLock = new Object();
+
     /**
      * Construct a new instance.
      *
@@ -76,7 +79,7 @@ public FramedMessageChannel(final ConnectedStreamChannel channel, final Pooled<B
 
     /** {@inheritDoc} */
     public int receive(final ByteBuffer buffer) throws IOException {
-        synchronized (receiveBuffer) {
+        synchronized (readLock) {
             if (isReadShutDown()) {
                 return -1;
             }
@@ -142,7 +145,7 @@ public long receive(final ByteBuffer[] buffers) throws IOException {
 
     /** {@inheritDoc} */
     public long receive(final ByteBuffer[] buffers, final int offs, final int len) throws IOException {
-        synchronized (receiveBuffer) {
+        synchronized (readLock) {
             if (isReadShutDown()) {
                 return -1;
             }
@@ -201,7 +204,7 @@ public long receive(final ByteBuffer[] buffers, final int offs, final int len) t
     }
 
     protected void shutdownReadsAction(final boolean writeComplete) throws IOException {
-        synchronized (receiveBuffer) {
+        synchronized (readLock) {
             log.tracef("Shutting down reads on %s", this);
             try {
                 receiveBuffer.getResource().clear();
@@ -217,7 +220,7 @@ protected void shutdownReadsAction(final boolean writeComplete) throws IOExcepti
 
     /** {@inheritDoc} */
     public boolean send(final ByteBuffer buffer) throws IOException {
-        synchronized (transmitBuffer) {
+        synchronized (writeLock) {
             if (isWriteShutDown()) {
                 throw new EOFException("Writes have been shut down");
             }
@@ -249,7 +252,7 @@ public boolean send(final ByteBuffer[] buffers) throws IOException {
 
     /** {@inheritDoc} */
     public boolean send(final ByteBuffer[] buffers, final int offs, final int len) throws IOException {
-        synchronized (transmitBuffer) {
+        synchronized (writeLock) {
             if (isWriteShutDown()) {
                 throw new EOFException("Writes have been shut down");
             }
@@ -275,13 +278,13 @@ public boolean send(final ByteBuffer[] buffers, final int offs, final int len) t
     }
 
     protected boolean flushAction(final boolean shutDown) throws IOException {
-        synchronized (transmitBuffer) {
+        synchronized (writeLock) {
             return (doFlushBuffer()) && channel.flush();
         }
     }
 
     protected void shutdownWritesComplete(final boolean readShutDown) throws IOException {
-        synchronized (transmitBuffer) {
+        synchronized (writeLock) {
             log.tracef("Finished shutting down writes on %s", this);
             try {
                 transmitBuffer.free();
@@ -291,7 +294,7 @@ protected void shutdownWritesComplete(final boolean readShutDown) throws IOExcep
     }
 
     private boolean doFlushBuffer() throws IOException {
-        assert Thread.holdsLock(transmitBuffer);
+        assert Thread.holdsLock(writeLock);
         final ByteBuffer buffer = transmitBuffer.getResource();
         buffer.flip();
         try {
@@ -316,7 +319,7 @@ private boolean doFlush() throws IOException {
     protected void closeAction(final boolean readShutDown, final boolean writeShutDown) throws IOException {
         boolean error = false;
         if (! writeShutDown) {
-            synchronized (transmitBuffer) {
+            synchronized (writeLock) {
                 try {
                     if (! doFlush()) error = true;
                 } catch (Throwable t) {
@@ -329,7 +332,7 @@ protected void closeAction(final boolean readShutDown, final boolean writeShutDo
             }
         }
         if (! readShutDown) {
-            synchronized (receiveBuffer) {
+            synchronized (readLock) {
                 try {
                     receiveBuffer.free();
                 } catch (Throwable t) {

diff --git a/api/src/main/java/org/xnio/ssl/JsseConnectedSslStreamChannel.java b/api/src/main/java/org/xnio/ssl/JsseConnectedSslStreamChannel.java
@@ -72,6 +72,9 @@ final class JsseConnectedSslStreamChannel extends TranslatingSuspendableChannel<
     /** The buffer into which inbound clear data is written. */
     private final Pooled<ByteBuffer> readBuffer;
 
+    private final Object readLock = new Object();
+    private final Object writeLock = new Object();
+
     // state
 
     private volatile boolean tls;
@@ -560,11 +563,11 @@ public SSLSession getSslSession() {
     }
 
     protected Object getReadLock() {
-        return receiveBuffer;
+        return readLock;
     }
 
     protected Object getWriteLock() {
-        return sendBuffer;
+        return writeLock;
     }
 
     protected void shutdownReadsAction(final boolean writeComplete) throws IOException {