From ed7613e1830a69da5370916dc8e9086b3cc231e4 Mon Sep 17 00:00:00 2001
From: John Fallows <john.fallows@kaazing.com>
Date: Sun, 5 Aug 2012 15:11:12 -0700
Subject: [PATCH] Resolve issue #489 with an atomic readInProgress guard to
 prevent ReadPendingException.

---
 .../io/netty/channel/socket/aio/AioSocketChannel.java    | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/transport/src/main/java/io/netty/channel/socket/aio/AioSocketChannel.java b/transport/src/main/java/io/netty/channel/socket/aio/AioSocketChannel.java
index 817cbc0af7..16a44c6c77 100755
--- a/transport/src/main/java/io/netty/channel/socket/aio/AioSocketChannel.java
+++ b/transport/src/main/java/io/netty/channel/socket/aio/AioSocketChannel.java
@@ -54,6 +54,7 @@ public class AioSocketChannel extends AbstractAioChannel implements SocketChanne
     private boolean flushing;
 
     private final AtomicBoolean readSuspended = new AtomicBoolean();
+    private final AtomicBoolean readInProgress = new AtomicBoolean();
 
     private final Runnable readTask = new Runnable() {
         @Override
@@ -191,6 +192,11 @@ public class AioSocketChannel extends AbstractAioChannel implements SocketChanne
             return;
         }
 
+        // prevent ReadPendingException
+        if (!readInProgress.compareAndSet(false, true)) {
+            return;
+        }
+
         ByteBuf byteBuf = pipeline().inboundByteBuffer();
         if (!byteBuf.readable()) {
             byteBuf.discardReadBytes();
@@ -297,6 +303,9 @@ public class AioSocketChannel extends AbstractAioChannel implements SocketChanne
                     }
                 }
             } finally {
+                // see beginRead
+                channel.readInProgress.set(false);
+
                 if (read) {
                     if (!channel.readSuspended.get()) {
                         pipeline.fireInboundBufferUpdated();