From e6ffa95fb425cc53a8347271e7ef72f0edeef057 Mon Sep 17 00:00:00 2001
From: Matt Joiner <anacrolix@gmail.com>
Date: Mon, 1 Dec 2014 03:27:52 -0600
Subject: [PATCH] When metainfo isn't complete, treat peers that don't support
 ut_metadata as useless

---
 worst_conns.go | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/worst_conns.go b/worst_conns.go
index 3b26c18f..3176ba2a 100644
--- a/worst_conns.go
+++ b/worst_conns.go
@@ -26,21 +26,32 @@ func (me *worstConns) Push(x interface{}) {
 }
 
 type worstConnsSortKey struct {
-	level int
-	age   time.Duration
+	// Peer has something we want.
+	useless bool
+	// A fabricated duration since peer was last helpful.
+	age time.Duration
 }
 
 func (me worstConnsSortKey) Less(other worstConnsSortKey) bool {
-	if me.level != other.level {
-		return me.level > other.level
+	if me.useless != other.useless {
+		return me.useless
 	}
 	return me.age > other.age
 }
 
 func (me worstConns) key(i int) (key worstConnsSortKey) {
 	c := me.c[i]
-	if time.Now().Sub(c.completedHandshake) >= 30*time.Second && !me.t.connHasWantedPieces(c) {
-		key.level = 1
+	// Peer has had time to declare what they have.
+	if time.Now().Sub(c.completedHandshake) >= 30*time.Second {
+		if !me.t.haveInfo() {
+			if _, ok := c.PeerExtensionIDs["ut_metadata"]; !ok {
+				key.useless = true
+			}
+		} else {
+			if !me.t.connHasWantedPieces(c) {
+				key.useless = true
+			}
+		}
 	}
 	key.age = time.Duration(1+3*c.UnwantedChunksReceived) * time.Now().Sub(func() time.Time {
 		if !c.lastUsefulChunkReceived.IsZero() {