From 034fece33f4fbabbf2bdf8c4fb643b91791438a7 Mon Sep 17 00:00:00 2001
From: Arceliar <Arceliar@users.noreply.github.com>
Date: Sat, 24 Aug 2019 13:15:29 -0500
Subject: [PATCH] more peer migration

---
 src/yggdrasil/peer.go   | 50 ++++++++++++++++-------------------------
 src/yggdrasil/switch.go |  4 ++--
 2 files changed, 21 insertions(+), 33 deletions(-)

diff --git a/src/yggdrasil/peer.go b/src/yggdrasil/peer.go
index 8c38c06..c94cf26 100644
--- a/src/yggdrasil/peer.go
+++ b/src/yggdrasil/peer.go
@@ -110,9 +110,9 @@ type peer struct {
 	endpoint   string
 	firstSeen  time.Time       // To track uptime for getPeers
 	linkOut    (chan []byte)   // used for protocol traffic (to bypass queues)
-	doSend     (chan struct{}) // tell the linkLoop to send a switchMsg
-	dinfo      (chan *dhtInfo) // used to keep the DHT working
+	dinfo      *dhtInfo        // used to keep the DHT working
 	out        func([][]byte)  // Set up by whatever created the peers struct, used to send packets to other nodes
+	done       (chan struct{}) // closed to exit the linkLoop
 	close      func()          // Called when a peer is removed, to close the underlying connection, or via admin api
 }
 
@@ -124,8 +124,7 @@ func (ps *peers) newPeer(box *crypto.BoxPubKey, sig *crypto.SigPubKey, linkShare
 		shared:     *crypto.GetSharedKey(&ps.core.boxPriv, box),
 		linkShared: *linkShared,
 		firstSeen:  now,
-		doSend:     make(chan struct{}, 1),
-		dinfo:      make(chan *dhtInfo, 1),
+		done:       make(chan struct{}),
 		close:      closer,
 		core:       ps.core,
 		intf:       intf,
@@ -170,29 +169,19 @@ func (ps *peers) removePeer(port switchPort) {
 		if p.close != nil {
 			p.close()
 		}
-		close(p.doSend)
+		close(p.done)
 	}
 }
 
 // If called, sends a notification to each peer that they should send a new switch message.
 // Mainly called by the switch after an update.
-func (ps *peers) sendSwitchMsgs() {
+func (ps *peers) sendSwitchMsgs(from phony.IActor) {
 	ports := ps.getPorts()
 	for _, p := range ports {
 		if p.port == 0 {
 			continue
 		}
-		p.doSendSwitchMsgs()
-	}
-}
-
-// If called, sends a notification to the peer's linkLoop to trigger a switchMsg send.
-// Mainly called by sendSwitchMsgs or during linkLoop startup.
-func (p *peer) doSendSwitchMsgs() {
-	defer func() { recover() }() // In case there's a race with close(p.doSend)
-	select {
-	case p.doSend <- struct{}{}:
-	default:
+		p.EnqueueFrom(from, p._sendSwitchMsg)
 	}
 }
 
@@ -201,24 +190,23 @@ func (p *peer) doSendSwitchMsgs() {
 func (p *peer) linkLoop() {
 	tick := time.NewTicker(time.Second)
 	defer tick.Stop()
-	p.doSendSwitchMsgs()
-	var dinfo *dhtInfo
+	<-p.SyncExec(p._sendSwitchMsg) // Startup message
 	for {
 		select {
-		case _, ok := <-p.doSend:
-			if !ok {
-				return
-			}
-			<-p.SyncExec(p._sendSwitchMsg)
-		case dinfo = <-p.dinfo:
+		case <-p.done:
+			return
 		case _ = <-tick.C:
-			if dinfo != nil {
-				<-p.SyncExec(func() { p.core.router.insertPeer(p, dinfo) })
-			}
+			<-p.SyncExec(p._updateDHT)
 		}
 	}
 }
 
+func (p *peer) _updateDHT() {
+	if p.dinfo != nil {
+		p.core.router.insertPeer(p, p.dinfo)
+	}
+}
+
 func (p *peer) handlePacketFrom(from phony.IActor, packet []byte) {
 	p.EnqueueFrom(from, func() {
 		p._handlePacket(packet)
@@ -366,16 +354,16 @@ func (p *peer) _handleSwitchMsg(packet []byte) {
 	p.core.switchTable.handleMsg(&msg, p.port)
 	if !p.core.switchTable.checkRoot(&msg) {
 		// Bad switch message
-		p.dinfo <- nil
+		p.dinfo = nil
 		return
 	}
 	// Pass a mesage to the dht informing it that this peer (still) exists
 	loc.coords = loc.coords[:len(loc.coords)-1]
-	dinfo := dhtInfo{
+	p.dinfo = &dhtInfo{
 		key:    p.box,
 		coords: loc.getCoords(),
 	}
-	p.dinfo <- &dinfo
+	p._updateDHT()
 }
 
 // This generates the bytes that we sign or check the signature of for a switchMsg.
diff --git a/src/yggdrasil/switch.go b/src/yggdrasil/switch.go
index d87b788..0be0124 100644
--- a/src/yggdrasil/switch.go
+++ b/src/yggdrasil/switch.go
@@ -248,7 +248,7 @@ func (t *switchTable) cleanRoot() {
 			t.core.router.reset(nil)
 		}
 		t.data.locator = switchLocator{root: t.key, tstamp: now.Unix()}
-		t.core.peers.sendSwitchMsgs()
+		t.core.peers.sendSwitchMsgs(nil) // TODO update if/when the switch becomes an actor
 	}
 }
 
@@ -515,7 +515,7 @@ func (t *switchTable) unlockedHandleMsg(msg *switchMsg, fromPort switchPort, rep
 		}
 		t.data.locator = sender.locator
 		t.parent = sender.port
-		t.core.peers.sendSwitchMsgs()
+		t.core.peers.sendSwitchMsgs(nil) // TODO update if/when the switch becomes an actor
 	}
 	if doUpdate {
 		t.updater.Store(&sync.Once{})