From db765e5dd43ac1d159a2ab342856a5dd71eab15b Mon Sep 17 00:00:00 2001
From: Norman Maurer <nmaurer@redhat.com>
Date: Wed, 23 Oct 2013 11:10:12 +0200
Subject: [PATCH] [#1812] Allow for inline for most common cases when use
 NioByteUnsafe.read()

---
 .../channel/nio/AbstractNioByteChannel.java   | 112 ++++++++----------
 1 file changed, 52 insertions(+), 60 deletions(-)

diff --git a/transport/src/main/java/io/netty/channel/nio/AbstractNioByteChannel.java b/transport/src/main/java/io/netty/channel/nio/AbstractNioByteChannel.java
index 712ad2ba26..a9577d82bf 100644
--- a/transport/src/main/java/io/netty/channel/nio/AbstractNioByteChannel.java
+++ b/transport/src/main/java/io/netty/channel/nio/AbstractNioByteChannel.java
@@ -56,88 +56,80 @@ public abstract class AbstractNioByteChannel extends AbstractNioChannel {
     private final class NioByteUnsafe extends AbstractNioUnsafe {
         private RecvByteBufAllocator.Handle allocHandle;
 
-        @Override
-        public void read() {
-            assert eventLoop().inEventLoop();
-            final SelectionKey key = selectionKey();
-            final ChannelConfig config = config();
-            if (!config.isAutoRead()) {
-                int interestOps = key.interestOps();
-                if ((interestOps & readInterestOp) != 0) {
-                    // only remove readInterestOp if needed
-                    key.interestOps(interestOps & ~readInterestOp);
+        private void removeReadOp() {
+            SelectionKey key = selectionKey();
+            int interestOps = key.interestOps();
+            if ((interestOps & readInterestOp) != 0) {
+                // only remove readInterestOp if needed
+                key.interestOps(interestOps & ~readInterestOp);
+            }
+        }
+
+        private void closeOnRead(ChannelPipeline pipeline) {
+            SelectionKey key = selectionKey();
+            setInputShutdown();
+            if (isOpen()) {
+                if (Boolean.TRUE.equals(config().getOption(ChannelOption.ALLOW_HALF_CLOSURE))) {
+                    key.interestOps(key.interestOps() & ~readInterestOp);
+                    pipeline.fireUserEventTriggered(ChannelInputShutdownEvent.INSTANCE);
+                } else {
+                    close(voidPromise());
                 }
             }
+        }
 
+        private void handleReadException(ChannelPipeline pipeline, ByteBuf byteBuf, Throwable cause, boolean close) {
+            if (byteBuf != null) {
+                if (byteBuf.isReadable()) {
+                    pipeline.fireChannelRead(byteBuf);
+                } else {
+                    byteBuf.release();
+                }
+            }
+            pipeline.fireChannelReadComplete();
+            if (close || cause instanceof IOException) {
+                closeOnRead(pipeline);
+            }
+        }
+
+        @Override
+        public void read() {
+            final ChannelConfig config = config();
             final ChannelPipeline pipeline = pipeline();
-
+            final ByteBufAllocator allocator = config.getAllocator();
+            final int maxMessagesPerRead = config.getMaxMessagesPerRead();
             RecvByteBufAllocator.Handle allocHandle = this.allocHandle;
             if (allocHandle == null) {
                 this.allocHandle = allocHandle = config.getRecvByteBufAllocator().newHandle();
             }
+            if (!config.isAutoRead()) {
+                removeReadOp();
+            }
 
-            final ByteBufAllocator allocator = config.getAllocator();
-            final int maxMessagesPerRead = config.getMaxMessagesPerRead();
-
-            boolean closed = false;
-            Throwable exception = null;
             ByteBuf byteBuf = null;
             int messages = 0;
+            boolean close = false;
             try {
-                for (;;) {
+                do {
                     byteBuf = allocHandle.allocate(allocator);
                     int localReadAmount = doReadBytes(byteBuf);
-                    if (localReadAmount == 0) {
-                        byteBuf.release();
-                        byteBuf = null;
+                    if (localReadAmount <= 0) {
+                        close = localReadAmount < 0;
                         break;
                     }
-                    if (localReadAmount < 0) {
-                        closed = true;
-                        byteBuf.release();
-                        byteBuf = null;
-                        break;
-                    }
-
                     pipeline.fireChannelRead(byteBuf);
-                    allocHandle.record(localReadAmount);
                     byteBuf = null;
-                    if (++ messages == maxMessagesPerRead) {
-                        break;
-                    }
-                }
-            } catch (Throwable t) {
-                exception = t;
-            } finally {
-                if (byteBuf != null) {
-                    if (byteBuf.isReadable()) {
-                        pipeline.fireChannelRead(byteBuf);
-                    } else {
-                        byteBuf.release();
-                    }
-                }
+                    allocHandle.record(localReadAmount);
+                } while (++ messages < maxMessagesPerRead);
 
                 pipeline.fireChannelReadComplete();
 
-                if (exception != null) {
-                    if (exception instanceof IOException) {
-                        closed = true;
-                    }
-
-                    pipeline().fireExceptionCaught(exception);
-                }
-
-                if (closed) {
-                    setInputShutdown();
-                    if (isOpen()) {
-                        if (Boolean.TRUE.equals(config().getOption(ChannelOption.ALLOW_HALF_CLOSURE))) {
-                            key.interestOps(key.interestOps() & ~readInterestOp);
-                            pipeline.fireUserEventTriggered(ChannelInputShutdownEvent.INSTANCE);
-                        } else {
-                            close(voidPromise());
-                        }
-                    }
+                if (close) {
+                    closeOnRead(pipeline);
+                    close = false;
                 }
+            } catch (Throwable t) {
+                handleReadException(pipeline, byteBuf, t, close);
             }
         }
     }