From e26bbfd4a714597cd09cdd75a0579c54b5f24798 Mon Sep 17 00:00:00 2001
From: Norman Maurer <nmaurer@redhat.com>
Date: Fri, 9 May 2014 08:31:07 +0200
Subject: [PATCH] Use ByteBuf.readSlice(...).retain() to minimize memory
 copies.

Motivation:
At the moment we call ByteBuf.readBytes(...) in these handlers but with optimizations done as part of 25e0d9d we can just use readSlice(...).retain() and eliminate the memory copy.

Modifications:
Replace ByteBuf.readBytes(...) usage with readSlice(...).retain().

Result:
Less memory copies.
---
 .../io/netty/handler/codec/DelimiterBasedFrameDecoder.java  | 6 +++---
 .../io/netty/handler/codec/FixedLengthFrameDecoder.java     | 2 +-
 .../java/io/netty/handler/codec/LineBasedFrameDecoder.java  | 6 +++---
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/codec/src/main/java/io/netty/handler/codec/DelimiterBasedFrameDecoder.java b/codec/src/main/java/io/netty/handler/codec/DelimiterBasedFrameDecoder.java
index e1cf93b45d..2dbd897ad6 100644
--- a/codec/src/main/java/io/netty/handler/codec/DelimiterBasedFrameDecoder.java
+++ b/codec/src/main/java/io/netty/handler/codec/DelimiterBasedFrameDecoder.java
@@ -268,13 +268,13 @@ public class DelimiterBasedFrameDecoder extends ByteToMessageDecoder {
             }
 
             if (stripDelimiter) {
-                frame = buffer.readBytes(minFrameLength);
+                frame = buffer.readSlice(minFrameLength);
                 buffer.skipBytes(minDelimLength);
             } else {
-                frame = buffer.readBytes(minFrameLength + minDelimLength);
+                frame = buffer.readSlice(minFrameLength + minDelimLength);
             }
 
-            return frame;
+            return frame.retain();
         } else {
             if (!discardingTooLongFrame) {
                 if (buffer.readableBytes() > maxFrameLength) {
diff --git a/codec/src/main/java/io/netty/handler/codec/FixedLengthFrameDecoder.java b/codec/src/main/java/io/netty/handler/codec/FixedLengthFrameDecoder.java
index b4435d97d8..bef42a6ab8 100644
--- a/codec/src/main/java/io/netty/handler/codec/FixedLengthFrameDecoder.java
+++ b/codec/src/main/java/io/netty/handler/codec/FixedLengthFrameDecoder.java
@@ -74,7 +74,7 @@ public class FixedLengthFrameDecoder extends ByteToMessageDecoder {
         if (in.readableBytes() < frameLength) {
             return null;
         } else {
-            return in.readBytes(frameLength);
+            return in.readSlice(frameLength).retain();
         }
     }
 }
diff --git a/codec/src/main/java/io/netty/handler/codec/LineBasedFrameDecoder.java b/codec/src/main/java/io/netty/handler/codec/LineBasedFrameDecoder.java
index f16646de02..ab49530de5 100644
--- a/codec/src/main/java/io/netty/handler/codec/LineBasedFrameDecoder.java
+++ b/codec/src/main/java/io/netty/handler/codec/LineBasedFrameDecoder.java
@@ -100,13 +100,13 @@ public class LineBasedFrameDecoder extends ByteToMessageDecoder {
                 }
 
                 if (stripDelimiter) {
-                    frame = buffer.readBytes(length);
+                    frame = buffer.readSlice(length);
                     buffer.skipBytes(delimLength);
                 } else {
-                    frame = buffer.readBytes(length + delimLength);
+                    frame = buffer.readSlice(length + delimLength);
                 }
 
-                return frame;
+                return frame.retain();
             } else {
                 final int length = buffer.readableBytes();
                 if (length > maxLength) {