From 922a2975e82d308e70e5d894b061007899455a50 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Sun, 17 Apr 2016 13:54:26 +0700
Subject: [PATCH] use PacketNumber type in ACK frame parsing, fix linter
 warnings

---
 frames/ack_frame.go      | 9 ++++++---
 frames/ack_frame_test.go | 5 +++--
 session.go               | 2 +-
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/frames/ack_frame.go b/frames/ack_frame.go
index 6080ce40..e7e1295c 100644
--- a/frames/ack_frame.go
+++ b/frames/ack_frame.go
@@ -3,13 +3,14 @@ package frames
 import (
 	"bytes"
 
+	"github.com/lucas-clemente/quic-go/protocol"
 	"github.com/lucas-clemente/quic-go/utils"
 )
 
 // An AckFrame in QUIC
 type AckFrame struct {
 	Entropy         byte
-	LargestObserved uint64
+	LargestObserved protocol.PacketNumber
 	DelayTime       uint16 // Todo: properly interpret this value as described in the specification
 }
 
@@ -47,20 +48,22 @@ func ParseAckFrame(r *bytes.Reader) (*AckFrame, error) {
 		largestObservedLen = 1
 	}
 
-	var missingSequenceNumberDeltaLen uint8 = 2 * (typeByte & 0x03)
+	missingSequenceNumberDeltaLen := 2 * (typeByte & 0x03)
 	if missingSequenceNumberDeltaLen == 0 {
 		missingSequenceNumberDeltaLen = 1
 	}
+	_ = missingSequenceNumberDeltaLen
 
 	frame.Entropy, err = r.ReadByte()
 	if err != nil {
 		return nil, err
 	}
 
-	frame.LargestObserved, err = utils.ReadUintN(r, largestObservedLen)
+	largestObserved, err := utils.ReadUintN(r, largestObservedLen)
 	if err != nil {
 		return nil, err
 	}
+	frame.LargestObserved = protocol.PacketNumber(largestObserved)
 
 	frame.DelayTime, err = utils.ReadUint16(r)
 	if err != nil {
diff --git a/frames/ack_frame_test.go b/frames/ack_frame_test.go
index 1d9e822f..2f15f075 100644
--- a/frames/ack_frame_test.go
+++ b/frames/ack_frame_test.go
@@ -3,6 +3,7 @@ package frames
 import (
 	"bytes"
 
+	"github.com/lucas-clemente/quic-go/protocol"
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
 )
@@ -14,7 +15,7 @@ var _ = Describe("AckFrame", func() {
 			frame, err := ParseAckFrame(b)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(frame.Entropy).To(Equal(byte(0xA4)))
-			Expect(frame.LargestObserved).To(Equal(uint64(0x03)))
+			Expect(frame.LargestObserved).To(Equal(protocol.PacketNumber(0x03)))
 			Expect(frame.DelayTime).To(Equal(uint16(0x4523)))
 			Expect(b.Len()).To(Equal(0))
 		})
@@ -23,7 +24,7 @@ var _ = Describe("AckFrame", func() {
 			b := bytes.NewReader([]byte{0x4C, 0xA4, 0x37, 0x13, 0xAD, 0xFB, 0xCA, 0xDE, 0x23, 0x45, 0x01, 0x02, 0xFF, 0xEE, 0xDD, 0xCC})
 			frame, err := ParseAckFrame(b)
 			Expect(err).ToNot(HaveOccurred())
-			Expect(frame.LargestObserved).To(Equal(uint64(0xDECAFBAD1337)))
+			Expect(frame.LargestObserved).To(Equal(protocol.PacketNumber(0xDECAFBAD1337)))
 			Expect(b.Len()).To(Equal(0))
 		})
 
diff --git a/session.go b/session.go
index ed3513b6..e5774662 100644
--- a/session.go
+++ b/session.go
@@ -80,7 +80,7 @@ func (s *Session) HandlePacket(addr *net.UDPAddr, publicHeaderBinary []byte, pub
 	s.Entropy.Add(publicHeader.PacketNumber, privateFlag&0x01 > 0)
 
 	s.SendFrames([]frames.Frame{&frames.AckFrame{
-		LargestObserved: uint64(publicHeader.PacketNumber),
+		LargestObserved: publicHeader.PacketNumber,
 		Entropy:         s.Entropy.Get(),
 	}})