From 1db7437b80d228ea8e84504fe3d253d41c573124 Mon Sep 17 00:00:00 2001
From: Arceliar <Arceliar@users.noreply.github.com>
Date: Sat, 29 May 2021 21:37:13 -0500
Subject: [PATCH] more cleanup and fix a busyloop when the admin socket is shut
 down

---
 src/admin/admin.go    | 29 +++++++++++++++++++++++++----
 src/core/core.go      | 13 +++++++++----
 src/core/core_test.go |  2 +-
 src/core/tcp.go       |  1 -
 src/tuntap/icmpv6.go  |  6 +-----
 5 files changed, 36 insertions(+), 15 deletions(-)

diff --git a/src/admin/admin.go b/src/admin/admin.go
index d2e066a3..8322b06f 100644
--- a/src/admin/admin.go
+++ b/src/admin/admin.go
@@ -25,7 +25,7 @@ type AdminSocket struct {
 	listenaddr string
 	listener   net.Listener
 	handlers   map[string]handler
-	started    bool
+	done       chan struct{}
 }
 
 type AdminSocketResponse struct {
@@ -69,6 +69,8 @@ func (a *AdminSocket) Init(c *core.Core, state *config.NodeState, log *log.Logge
 	a.handlers = make(map[string]handler)
 	current := state.GetCurrent()
 	a.listenaddr = current.AdminListen
+	a.done = make(chan struct{})
+	close(a.done) // Start in a done / not-started state
 	_ = a.AddHandler("list", []string{}, func(_ json.RawMessage) (interface{}, error) {
 		res := &ListResponse{
 			List: map[string]ListEntry{},
@@ -144,21 +146,32 @@ func (a *AdminSocket) SetupAdminHandlers(na *AdminSocket) {
 // Start runs the admin API socket to listen for / respond to admin API calls.
 func (a *AdminSocket) Start() error {
 	if a.listenaddr != "none" && a.listenaddr != "" {
+		a.done = make(chan struct{})
 		go a.listen()
-		a.started = true
 	}
 	return nil
 }
 
 // IsStarted returns true if the module has been started.
 func (a *AdminSocket) IsStarted() bool {
-	return a.started
+	select {
+	case <-a.done:
+		// Not blocking, so we're not currently running
+		return false
+	default:
+		// Blocked, so we must have started
+		return true
+	}
 }
 
 // Stop will stop the admin API and close the socket.
 func (a *AdminSocket) Stop() error {
 	if a.listener != nil {
-		a.started = false
+		select {
+		case <-a.done:
+		default:
+			close(a.done)
+		}
 		return a.listener.Close()
 	}
 	return nil
@@ -215,6 +228,14 @@ func (a *AdminSocket) listen() {
 		conn, err := a.listener.Accept()
 		if err == nil {
 			go a.handleRequest(conn)
+		} else {
+			select {
+			case <-a.done:
+				// Not blocked, so we havent started or already stopped
+				return
+			default:
+				// Blocked, so we're supposed to keep running
+			}
 		}
 	}
 }
diff --git a/src/core/core.go b/src/core/core.go
index ba2b89b0..f3942cdb 100644
--- a/src/core/core.go
+++ b/src/core/core.go
@@ -95,9 +95,11 @@ func (c *Core) _addPeerLoop() {
 		}
 	}
 
-	c.addPeerTimer = time.AfterFunc(time.Minute, func() {
-		c.Act(nil, c._addPeerLoop)
-	})
+	if c.addPeerTimer != nil {
+		c.addPeerTimer = time.AfterFunc(time.Minute, func() {
+			c.Act(nil, c._addPeerLoop)
+		})
+	}
 }
 
 // Start starts up Yggdrasil using the provided config.NodeConfig, and outputs
@@ -149,7 +151,9 @@ func (c *Core) _start(nc *config.NodeConfig, log *log.Logger) (*config.NodeState
 	//	return nil, err
 	//}
 
-	c.Act(c, c._addPeerLoop)
+	c.addPeerTimer = time.AfterFunc(0, func() {
+		c.Act(nil, c._addPeerLoop)
+	})
 
 	c.log.Infoln("Startup complete")
 	return &c.config, nil
@@ -166,6 +170,7 @@ func (c *Core) _stop() {
 	c.log.Infoln("Stopping...")
 	if c.addPeerTimer != nil {
 		c.addPeerTimer.Stop()
+		c.addPeerTimer = nil
 	}
 	c.links.stop()
 	/* FIXME this deadlocks, need a waitgroup or something to coordinate shutdown
diff --git a/src/core/core_test.go b/src/core/core_test.go
index 224907b9..ce4a4156 100644
--- a/src/core/core_test.go
+++ b/src/core/core_test.go
@@ -142,7 +142,7 @@ func TestCore_Start_Transfer(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if bytes.Compare(msg, buf) != 0 {
+	if !bytes.Equal(msg, buf) {
 		t.Fatal("expected echo")
 	}
 	<-done
diff --git a/src/core/tcp.go b/src/core/tcp.go
index 48163e8c..eced7726 100644
--- a/src/core/tcp.go
+++ b/src/core/tcp.go
@@ -31,7 +31,6 @@ import (
 )
 
 const default_timeout = 6 * time.Second
-const tcp_ping_interval = (default_timeout * 2 / 3)
 
 // The TCP listener and information about active TCP connections, to avoid duplication.
 type tcp struct {
diff --git a/src/tuntap/icmpv6.go b/src/tuntap/icmpv6.go
index 59d07af3..b7461a2d 100644
--- a/src/tuntap/icmpv6.go
+++ b/src/tuntap/icmpv6.go
@@ -17,11 +17,7 @@ import (
 	"golang.org/x/net/ipv6"
 )
 
-const len_ETHER = 14
-
-type ICMPv6 struct {
-	tun *TunAdapter
-}
+type ICMPv6 struct{}
 
 // Marshal returns the binary encoding of h.
 func ipv6Header_Marshal(h *ipv6.Header) ([]byte, error) {