From 9125a29e79fedd72b09306f90358426cd9afc915 Mon Sep 17 00:00:00 2001
From: 9seconds <nineseconds@yandex.ru>
Date: Mon, 23 Mar 2020 17:08:13 +0300
Subject: [PATCH] Add pools for packetack

---
 wrappers/packetack/client_abridged.go         |  4 +-
 .../packetack/client_intermediate_secure.go   |  7 ++--
 wrappers/packetack/pools.go                   | 37 +++++++++++++++++++
 wrappers/packetack/proxy.go                   |  3 +-
 4 files changed, 46 insertions(+), 5 deletions(-)
 create mode 100644 wrappers/packetack/pools.go

diff --git a/wrappers/packetack/client_abridged.go b/wrappers/packetack/client_abridged.go
index 1b8aa9a..556a4f2 100644
--- a/wrappers/packetack/client_abridged.go
+++ b/wrappers/packetack/client_abridged.go
@@ -88,7 +88,9 @@ func (w *wrapperClientAbridged) Write(packet conntypes.Packet, acks *conntypes.C
 		return nil
 	case packetLength < clientAbridgedLargePacketLength:
 		length24 := utils.ToUint24(uint32(packetLength))
-		buf := bytes.Buffer{}
+
+		buf := acquireClientBytesBuffer()
+		defer releaseClientBytesBuffer(buf)
 
 		buf.WriteByte(byte(clientAbridgedSmallPacketLength))
 		buf.Write(length24[:])
diff --git a/wrappers/packetack/client_intermediate_secure.go b/wrappers/packetack/client_intermediate_secure.go
index 153e779..9c3c448 100644
--- a/wrappers/packetack/client_intermediate_secure.go
+++ b/wrappers/packetack/client_intermediate_secure.go
@@ -1,7 +1,6 @@
 package packetack
 
 import (
-	"bytes"
 	"encoding/binary"
 	"fmt"
 	"math/rand"
@@ -35,11 +34,13 @@ func (w *wrapperClientIntermediateSecure) Write(packet conntypes.Packet, acks *c
 		return nil
 	}
 
-	buf := bytes.Buffer{}
+	buf := acquireClientBytesBuffer()
+	defer releaseClientBytesBuffer(buf)
+
 	paddingLength := rand.Intn(4)
 	buf.Grow(4 + len(packet) + paddingLength)
 
-	binary.Write(&buf, binary.LittleEndian, uint32(len(packet)+paddingLength)) // nolint: errcheck
+	binary.Write(buf, binary.LittleEndian, uint32(len(packet)+paddingLength)) // nolint: errcheck
 	buf.Write(packet)
 	buf.Write(make([]byte, paddingLength))
 
diff --git a/wrappers/packetack/pools.go b/wrappers/packetack/pools.go
new file mode 100644
index 0000000..7cd7fd5
--- /dev/null
+++ b/wrappers/packetack/pools.go
@@ -0,0 +1,37 @@
+package packetack
+
+import (
+	"bytes"
+	"sync"
+)
+
+var (
+	poolClientBytesBuffer = sync.Pool{
+		New: func() interface{} {
+			return &bytes.Buffer{}
+		},
+	}
+	poolProxyBytesBuffer = sync.Pool{
+		New: func() interface{} {
+			return &bytes.Buffer{}
+		},
+	}
+)
+
+func acquireClientBytesBuffer() *bytes.Buffer {
+	return poolClientBytesBuffer.Get().(*bytes.Buffer)
+}
+
+func acquireProxyBytesBuffer() *bytes.Buffer {
+	return poolProxyBytesBuffer.Get().(*bytes.Buffer)
+}
+
+func releaseClientBytesBuffer(buf *bytes.Buffer) {
+	buf.Reset()
+	poolClientBytesBuffer.Put(buf)
+}
+
+func releaseProxyBytesBuffer(buf *bytes.Buffer) {
+	buf.Reset()
+	poolProxyBytesBuffer.Put(buf)
+}
diff --git a/wrappers/packetack/proxy.go b/wrappers/packetack/proxy.go
index 62ac7d2..25ae6cb 100644
--- a/wrappers/packetack/proxy.go
+++ b/wrappers/packetack/proxy.go
@@ -22,7 +22,8 @@ type wrapperProxy struct {
 }
 
 func (w *wrapperProxy) Write(packet conntypes.Packet, acks *conntypes.ConnectionAcks) error {
-	buf := bytes.Buffer{}
+	buf := acquireProxyBytesBuffer()
+	defer releaseProxyBytesBuffer(buf)
 
 	flags := w.flags
 	if acks.Quick {