From 293a0e8e202a20891e8aa7ef4ca1a97d11fd2b4b Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Wed, 25 Mar 2020 10:53:08 +0100
Subject: [PATCH] Move upstreamConn.ring to network

This handles upstream disconnection and re-connection better.
---
 downstream.go | 23 +++++++++++++++--------
 upstream.go   |  4 +---
 user.go       |  2 ++
 3 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/downstream.go b/downstream.go
index 3bf3da6..cd2cb77 100644
--- a/downstream.go
+++ b/downstream.go
@@ -699,27 +699,34 @@ func (dc *downstreamConn) register() error {
 				forwardChannel(dc, ch)
 			}
 		}
+	})
 
+	dc.forEachNetwork(func(net *network) {
 		historyName := dc.rawUsername
 
 		// TODO: need to take dc.network into account here
 		var seqPtr *uint64
 		if firstDownstream {
-			uc.network.lock.Lock()
-			seq, ok := uc.network.history[historyName]
-			uc.network.lock.Unlock()
+			net.lock.Lock()
+			seq, ok := net.history[historyName]
+			net.lock.Unlock()
 			if ok {
 				seqPtr = &seq
 			}
 		}
 
 		// TODO: we need to create a consumer when adding networks on-the-fly
-		consumer, ch := uc.ring.NewConsumer(seqPtr)
+		consumer, ch := net.ring.NewConsumer(seqPtr)
 		go func() {
 			for {
 				var closed bool
 				select {
 				case <-ch:
+					uc := net.upstream()
+					if uc == nil {
+						dc.logger.Printf("ignoring messages for upstream %q: upstream is disconnected", net.Addr)
+						break
+					}
 					dc.ringMessages <- ringMessage{consumer, uc}
 				case <-dc.closed:
 					closed = true
@@ -737,9 +744,9 @@ func (dc *downstreamConn) register() error {
 			dc.user.lock.Unlock()
 
 			if lastDownstream {
-				uc.network.lock.Lock()
-				uc.network.history[historyName] = seq
-				uc.network.lock.Unlock()
+				net.lock.Lock()
+				net.history[historyName] = seq
+				net.lock.Unlock()
 			}
 		}()
 	})
@@ -1086,7 +1093,7 @@ func (dc *downstreamConn) handleMessageRegistered(msg *irc.Message) error {
 			dc.ourMessages[echoMsg] = struct{}{}
 			dc.lock.Unlock()
 
-			uc.ring.Produce(echoMsg)
+			uc.network.ring.Produce(echoMsg)
 		}
 	default:
 		dc.logger.Printf("unhandled message: %v", msg)
diff --git a/upstream.go b/upstream.go
index 7ef5f7e..0dff3c3 100644
--- a/upstream.go
+++ b/upstream.go
@@ -34,7 +34,6 @@ type upstreamConn struct {
 	srv      *Server
 	user     *user
 	outgoing chan<- *irc.Message
-	ring     *Ring
 
 	serverName            string
 	availableUserModes    string
@@ -80,7 +79,6 @@ func connectToUpstream(network *network) (*upstreamConn, error) {
 		srv:                   network.user.srv,
 		user:                  network.user,
 		outgoing:              outgoing,
-		ring:                  NewRing(network.user.srv.RingCap),
 		channels:              make(map[string]*upstreamChannel),
 		caps:                  make(map[string]string),
 		availableChannelTypes: stdChannelTypes,
@@ -874,7 +872,7 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 			break
 		}
 
-		uc.ring.Produce(msg)
+		uc.network.ring.Produce(msg)
 	case "INVITE":
 		var nick string
 		var channel string
diff --git a/user.go b/user.go
index 245664c..b4e4060 100644
--- a/user.go
+++ b/user.go
@@ -20,6 +20,7 @@ type downstreamIncomingMessage struct {
 type network struct {
 	Network
 	user *user
+	ring *Ring
 
 	lock    sync.Mutex
 	conn    *upstreamConn
@@ -30,6 +31,7 @@ func newNetwork(user *user, record *Network) *network {
 	return &network{
 		Network: *record,
 		user:    user,
+		ring:    NewRing(user.srv.RingCap),
 		history: make(map[string]uint64),
 	}
 }