Remove locking in favour of a volatile state variable.

CraftBukkit-Patches/0026-Netty.patch

@@ -1,4 +1,4 @@
-From 840a6fa0c4febdcdb5b9e0a7af30a7d04d7e3172 Mon Sep 17 00:00:00 2001
+From d5543f1ee66f0f7e7ad7dad7220887d6014feb5f Mon Sep 17 00:00:00 2001
 From: md_5 <md_5@live.com.au>
 Date: Sun, 3 Feb 2013 10:24:33 +1100
 Subject: [PATCH] Netty
@@ -17,14 +17,14 @@ This commit is licensed under the Creative Commons Attribution-ShareAlike 3.0 Un
  .../net/minecraft/server/PendingConnection.java    |  15 +-
  .../net/minecraft/server/PlayerConnection.java     |   2 +-
  src/main/java/org/spigotmc/netty/CipherCodec.java  |  65 ++++++
- .../org/spigotmc/netty/NettyNetworkManager.java    | 221 ++++++++++++++++++
+ .../org/spigotmc/netty/NettyNetworkManager.java    | 206 +++++++++++++++++
  .../org/spigotmc/netty/NettyServerConnection.java  | 105 +++++++++
  .../org/spigotmc/netty/NettySocketAdaptor.java     | 248 +++++++++++++++++++++
  .../java/org/spigotmc/netty/PacketDecoder.java     |  63 ++++++
  .../java/org/spigotmc/netty/PacketEncoder.java     |  43 ++++
  .../java/org/spigotmc/netty/PacketListener.java    | 100 +++++++++
  src/main/java/org/spigotmc/netty/ReadState.java    |  16 ++
- 12 files changed, 883 insertions(+), 7 deletions(-)
+ 12 files changed, 868 insertions(+), 7 deletions(-)
  create mode 100644 src/main/java/org/spigotmc/netty/CipherCodec.java
  create mode 100644 src/main/java/org/spigotmc/netty/NettyNetworkManager.java
  create mode 100644 src/main/java/org/spigotmc/netty/NettyServerConnection.java
@@ -210,10 +210,10 @@ index 0000000..cfc0535
 +}
 diff --git a/src/main/java/org/spigotmc/netty/NettyNetworkManager.java b/src/main/java/org/spigotmc/netty/NettyNetworkManager.java
 new file mode 100644
-index 0000000..81164a4
+index 0000000..90c63e1
 --- /dev/null
 +++ b/src/main/java/org/spigotmc/netty/NettyNetworkManager.java
-@@ -0,0 +1,221 @@
+@@ -0,0 +1,206 @@
 +package org.spigotmc.netty;
 +
 +import io.netty.channel.Channel;
@@ -249,8 +249,8 @@ index 0000000..81164a4
 +    private static final PrivateKey key = server.F().getPrivate();
 +    private static final NettyServerConnection serverConnection = (NettyServerConnection) server.ae();
 +    /*========================================================================*/
-+    private final Object mutex = new Object();
 +    private final Queue<Packet> syncPackets = new ConcurrentLinkedQueue<Packet>();
++    private volatile boolean connected;
 +    private Channel channel;
 +    private SocketAddress address;
 +    private Connection handler;
@@ -261,7 +261,6 @@ index 0000000..81164a4
 +
 +    @Override
 +    public void channelActive(ChannelHandlerContext ctx) throws Exception {
-+        synchronized (mutex) {
 +        // Channel and address groundwork first
 +        channel = ctx.channel();
 +        address = channel.remoteAddress();
@@ -270,33 +269,24 @@ index 0000000..81164a4
 +        // Followed by their first handler
 +        handler = new PendingConnection(server, this);
 +        // Finally register the connection
++        connected = true;
 +        serverConnection.pendingConnections.add((PendingConnection) handler);
 +    }
-+    }
 +
 +    @Override
 +    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
-+        synchronized (mutex) {
-+            if (dcReason == null || dcArgs == null) {
 +        a("disconnect.endOfStream", new Object[0]);
 +    }
-+            // Remove channel reference to indicate we are done
-+            channel = null;
-+        }
-+    }
 +
 +    @Override
 +    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
-+        synchronized (mutex) {
 +        // TODO: Remove this once we are more stable
 +        // Bukkit.getServer().getLogger().severe("======================= Start Netty Debug Log =======================");
 +        // Bukkit.getServer().getLogger().log(Level.SEVERE, "Error caught whilst handling " + channel, cause);
 +        // Bukkit.getServer().getLogger().severe("======================= End Netty Debug Log =======================");
-+
 +        // Disconnect with generic reason + exception
 +        a("disconnect.genericReason", new Object[]{"Internal exception: " + cause});
 +    }
-+    }
 +
 +    @Override
 +    public void messageReceived(ChannelHandlerContext ctx, final Packet msg) throws Exception {
@@ -338,9 +328,8 @@ index 0000000..81164a4
 +     * @param packet the packet to queue
 +     */
 +    public void queue(Packet packet) {
-+        synchronized (mutex) {
 +        // Only send if channel is still connected
-+            if (channel != null) {
++        if (connected) {
 +            // Process packet via handler
 +            packet = PacketListener.callQueued(this, handler, packet);
 +            // If handler indicates packet send
@@ -357,7 +346,6 @@ index 0000000..81164a4
 +            }
 +        }
 +    }
-+    }
 +
 +    /**
 +     * wakeThreads. In Vanilla this method will interrupt the network read and
@@ -381,7 +369,7 @@ index 0000000..81164a4
 +        }
 +
 +        // Disconnect via the handler - this performs all plugin related cleanup + logging
-+        if ((dcReason != null || dcArgs != null) && syncPackets.isEmpty()) {
++        if (!connected) {
 +            handler.a(dcReason, dcArgs);
 +        }
 +    }
@@ -400,12 +388,11 @@ index 0000000..81164a4
 +     * close. Close and release all resources associated with this connection.
 +     */
 +    public void d() {
-+        synchronized (mutex) {
++        if (connected) {
-+            if (channel != null) {
++            connected = false;
 +            channel.close();
 +        }
 +    }
-+    }
 +
 +    /**
 +     * queueSize. Return the number of packets in the low priority queue. In a
@@ -426,12 +413,10 @@ index 0000000..81164a4
 +     * exception which triggered the disconnect.
 +     */
 +    public void a(String reason, Object... arguments) {
-+        synchronized (mutex) {
++        if (connected) {
-+            if (channel != null) {
 +            dcReason = reason;
 +            dcArgs = arguments;
-+                channel.close();
++            d();
-+            }
 +        }
 +    }
 +}