From b36ffe1c9d570051a79ddb025071a0806e933c7a Mon Sep 17 00:00:00 2001
From: David Wragg <david@wragg.org>
Date: Tue, 13 Oct 2015 15:20:42 +0100
Subject: [PATCH] Support peers that don't have short IDs

---
 router/connection.go | 19 +++++++++++++------
 router/peer.go       | 22 ++++++++++++----------
 router/peers.go      |  8 ++++++++
 3 files changed, 33 insertions(+), 16 deletions(-)

diff --git a/router/connection.go b/router/connection.go
index 926d1392..9f047159 100644
--- a/router/connection.go
+++ b/router/connection.go
@@ -277,7 +277,7 @@ func (features features) Get(key string) string {
 }
 
 func (conn *LocalConnection) parseFeatures(features features) (*Peer, error) {
-	if err := features.MustHave([]string{"PeerNameFlavour", "Name", "NickName", "ShortID", "UID", "ConnID"}); err != nil {
+	if err := features.MustHave([]string{"PeerNameFlavour", "Name", "NickName", "UID", "ConnID"}); err != nil {
 		return nil, err
 	}
 
@@ -293,10 +293,15 @@ func (conn *LocalConnection) parseFeatures(features features) (*Peer, error) {
 
 	nickName := features.Get("NickName")
 
-	shortID, err := strconv.ParseUint(features.Get("ShortID"), 10,
-		PeerShortIDBits)
-	if err != nil {
-		return nil, err
+	var shortID uint64
+	var hasShortID bool
+	if shortIDStr, present := features["ShortID"]; present {
+		hasShortID = true
+		shortID, err = strconv.ParseUint(shortIDStr, 10,
+			PeerShortIDBits)
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	uid, err := ParsePeerUID(features.Get("UID"))
@@ -310,7 +315,9 @@ func (conn *LocalConnection) parseFeatures(features features) (*Peer, error) {
 	}
 
 	conn.uid ^= remoteConnID
-	return NewPeer(name, nickName, uid, 0, PeerShortID(shortID)), nil
+	peer := NewPeer(name, nickName, uid, 0, PeerShortID(shortID))
+	peer.HasShortID = hasShortID
+	return peer, nil
 }
 
 func (conn *LocalConnection) registerRemote(remote *Peer, acceptNewPeer bool) error {
diff --git a/router/peer.go b/router/peer.go
index 82ae2201..e73d1592 100644
--- a/router/peer.go
+++ b/router/peer.go
@@ -30,11 +30,12 @@ func randomPeerShortID() PeerShortID {
 }
 
 type PeerSummary struct {
-	NameByte []byte
-	NickName string
-	UID      PeerUID
-	Version  uint64
-	ShortID  PeerShortID
+	NameByte   []byte
+	NickName   string
+	UID        PeerUID
+	Version    uint64
+	ShortID    PeerShortID
+	HasShortID bool
 }
 
 type Peer struct {
@@ -56,11 +57,12 @@ func NewPeerFromSummary(summary PeerSummary) *Peer {
 
 func NewPeer(name PeerName, nickName string, uid PeerUID, version uint64, shortID PeerShortID) *Peer {
 	return NewPeerFromSummary(PeerSummary{
-		NameByte: name.Bin(),
-		NickName: nickName,
-		UID:      uid,
-		Version:  version,
-		ShortID:  shortID,
+		NameByte:   name.Bin(),
+		NickName:   nickName,
+		UID:        uid,
+		Version:    version,
+		ShortID:    shortID,
+		HasShortID: true,
 	})
 }
 
diff --git a/router/peers.go b/router/peers.go
index 163f8c48..098a7825 100644
--- a/router/peers.go
+++ b/router/peers.go
@@ -114,6 +114,10 @@ func (peers *Peers) unlockAndNotify(pending *PeersPendingNotifications) {
 }
 
 func (peers *Peers) addByShortID(peer *Peer, pending *PeersPendingNotifications) {
+	if !peer.HasShortID {
+		return
+	}
+
 	entry, ok := peers.byShortID[peer.ShortID]
 	if !ok {
 		entry = ShortIDPeers{peer: peer}
@@ -146,6 +150,10 @@ func (peers *Peers) addByShortID(peer *Peer, pending *PeersPendingNotifications)
 }
 
 func (peers *Peers) deleteByShortID(peer *Peer, pending *PeersPendingNotifications) {
+	if !peer.HasShortID {
+		return
+	}
+
 	entry := peers.byShortID[peer.ShortID]
 	var otherIndex int