From f35047765f00de1d642d23bc0f980fa8eceacf3b Mon Sep 17 00:00:00 2001
From: Nikolay Fedorovskikh <fenik17@gmail.com>
Date: Wed, 28 Jun 2017 15:42:03 +0500
Subject: [PATCH] Avoid a double check ByteBuf#ensureWritable in ByteBufUtil

Motivation:

Methods `ByteBufUtil#writeUtf8` and `ByteBufUtil#writeAscii` contains a check `ByteBuf#ensureWritable` before the calling `ByteBuf#writeBytes`. But the `ByteBuf#writeBytes` also do a such check inside.

Modifications:

Make checks more targeted.

Result:

Less redundant method calls.
---
 buffer/src/main/java/io/netty/buffer/ByteBufUtil.java | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java b/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
index 5ad957108d..553ebc7b79 100644
--- a/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
+++ b/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
@@ -444,13 +444,11 @@ public final class ByteBufUtil {
      * This method returns the actual number of bytes written.
      */
     public static int writeUtf8(ByteBuf buf, CharSequence seq) {
-        final int len = seq.length();
-        buf.ensureWritable(utf8MaxBytes(seq));
-
         for (;;) {
             if (buf instanceof AbstractByteBuf) {
                 AbstractByteBuf byteBuf = (AbstractByteBuf) buf;
-                int written = writeUtf8(byteBuf, byteBuf.writerIndex, seq, len);
+                byteBuf.ensureWritable(utf8MaxBytes(seq));
+                int written = writeUtf8(byteBuf, byteBuf.writerIndex, seq, seq.length());
                 byteBuf.writerIndex += written;
                 return written;
             } else if (buf instanceof WrappedByteBuf) {
@@ -543,14 +541,14 @@ public final class ByteBufUtil {
     public static int writeAscii(ByteBuf buf, CharSequence seq) {
         // ASCII uses 1 byte per char
         final int len = seq.length();
-        buf.ensureWritable(len);
         if (seq instanceof AsciiString) {
             AsciiString asciiString = (AsciiString) seq;
-            buf.writeBytes(asciiString.array(), asciiString.arrayOffset(), asciiString.length());
+            buf.writeBytes(asciiString.array(), asciiString.arrayOffset(), len);
         } else {
             for (;;) {
                 if (buf instanceof AbstractByteBuf) {
                     AbstractByteBuf byteBuf = (AbstractByteBuf) buf;
+                    byteBuf.ensureWritable(len);
                     int written = writeAscii(byteBuf, byteBuf.writerIndex, seq, len);
                     byteBuf.writerIndex += written;
                     return written;