make putting back packet buffers a member function of packetBuffer

buffer_pool.go

@@ -22,6 +22,23 @@ func (b *packetBuffer) Split() {
 	b.refCount++
 }
 
+// Release decreases the refCount.
+// It should be called when processing the packet is finished.
+// When the refCount reaches 0, the packet buffer is put back into the pool.
+func (b *packetBuffer) Release() {
+	if cap(b.Slice) != int(protocol.MaxReceivePacketSize) {
+		panic("putPacketBuffer called with packet of wrong size!")
+	}
+	b.refCount--
+	if b.refCount < 0 {
+		panic("negative packetBuffer refCount")
+	}
+	// only put the packetBuffer back if it's not used any more
+	if b.refCount == 0 {
+		bufferPool.Put(b)
+	}
+}
+
 var bufferPool sync.Pool
 
 func getPacketBuffer() *packetBuffer {
@@ -31,20 +48,6 @@ func getPacketBuffer() *packetBuffer {
 	return buf
 }
 
-func putPacketBuffer(buf *packetBuffer) {
-	if cap(buf.Slice) != int(protocol.MaxReceivePacketSize) {
-		panic("putPacketBuffer called with packet of wrong size!")
-	}
-	buf.refCount--
-	if buf.refCount < 0 {
-		panic("negative packetBuffer refCount")
-	}
-	// only put the packetBuffer back if it's not used any more
-	if buf.refCount == 0 {
-		bufferPool.Put(buf)
-	}
-}
-
 func init() {
 	bufferPool.New = func() interface{} {
 		return &packetBuffer{

buffer_pool_test.go

@@ -13,31 +13,31 @@ var _ = Describe("Buffer Pool", func() {
 		Expect(buf.Slice).To(HaveCap(int(protocol.MaxReceivePacketSize)))
 	})
 
-	It("puts buffers back", func() {
+	It("releases buffers", func() {
 		buf := getPacketBuffer()
-		putPacketBuffer(buf)
+		buf.Release()
 	})
 
 	It("panics if wrong-sized buffers are passed", func() {
 		buf := getPacketBuffer()
 		buf.Slice = make([]byte, 10)
-		Expect(func() { putPacketBuffer(buf) }).To(Panic())
+		Expect(func() { buf.Release() }).To(Panic())
 	})
 
-	It("panics if it is put pack twice", func() {
+	It("panics if it is released twice", func() {
 		buf := getPacketBuffer()
-		putPacketBuffer(buf)
+		buf.Release()
-		Expect(func() { putPacketBuffer(buf) }).To(Panic())
+		Expect(func() { buf.Release() }).To(Panic())
 	})
 
-	It("waits until all parts have been put back", func() {
+	It("waits until all parts have been released", func() {
 		buf := getPacketBuffer()
 		buf.Split()
 		buf.Split()
 		// now we have 3 parts
-		putPacketBuffer(buf)
+		buf.Release()
-		putPacketBuffer(buf)
+		buf.Release()
-		putPacketBuffer(buf)
+		buf.Release()
-		Expect(func() { putPacketBuffer(buf) }).To(Panic())
+		Expect(func() { buf.Release() }).To(Panic())
 	})
 })

packet_handler_map.go

@@ -169,7 +169,7 @@ func (h *packetHandlerMap) handlePacket(
 		// We still need to process the packets that were successfully parsed before.
 	}
 	if len(packets) == 0 {
-		putPacketBuffer(buffer)
+		buffer.Release()
 		return
 	}
 	h.handleParsedPackets(packets)

server.go

@@ -321,20 +321,20 @@ func (s *server) handlePacket(p *receivedPacket) {
 		return
 	}
 
-	putPacketBuffer(p.buffer)
 	// TODO(#943): send Stateless Reset
+	p.buffer.Release()
 }
 
 func (s *server) handleInitial(p *receivedPacket) {
 	s.logger.Debugf("<- Received Initial packet.")
 	sess, connID, err := s.handleInitialImpl(p)
 	if err != nil {
-		putPacketBuffer(p.buffer)
+		p.buffer.Release()
 		s.logger.Errorf("Error occurred handling initial packet: %s", err)
 		return
 	}
 	if sess == nil { // a retry was done
-		putPacketBuffer(p.buffer)
+		p.buffer.Release()
 		return
 	}
 	// Don't put the packet buffer back if a new session was created.
@@ -461,7 +461,7 @@ func (s *server) sendRetry(remoteAddr net.Addr, hdr *wire.Header) error {
 }
 
 func (s *server) sendVersionNegotiationPacket(p *receivedPacket) {
-	defer putPacketBuffer(p.buffer)
+	defer p.buffer.Release()
 	hdr := p.hdr
 	s.logger.Debugf("Client offered version %s, sending Version Negotiation", hdr.Version)
 	data, err := wire.ComposeVersionNegotiation(hdr.SrcConnectionID, hdr.DestConnectionID, s.config.Versions)

session.go

@@ -479,7 +479,7 @@ func (s *session) handlePacketImpl(p *receivedPacket) bool /* was the packet suc
 	defer func() {
 		// Put back the packet buffer if the packet wasn't queued for later decryption.
 		if !wasQueued {
-			putPacketBuffer(p.buffer)
+			p.buffer.Release()
 		}
 	}()
 
@@ -962,7 +962,7 @@ func (s *session) sendPacket() (bool, error) {
 }
 
 func (s *session) sendPackedPacket(packet *packedPacket) error {
-	defer putPacketBuffer(packet.buffer)
+	defer packet.buffer.Release()
 	s.logPacket(packet)
 	return s.conn.Write(packet.raw)
 }