lib: Replace done channel with contexts in and add names to util services (#6166)

lib/beacon/beacon.go

@@ -7,6 +7,7 @@
 package beacon
 
 import (
+	"context"
 	"fmt"
 	"net"
 	"time"
@@ -63,23 +64,23 @@ func newCast(name string) *cast {
 	}
 }
 
-func (c *cast) addReader(svc func(chan struct{}) error) {
+func (c *cast) addReader(svc func(context.Context) error) {
 	c.reader = c.createService(svc, "reader")
 	c.Add(c.reader)
 }
 
-func (c *cast) addWriter(svc func(stop chan struct{}) error) {
+func (c *cast) addWriter(svc func(ctx context.Context) error) {
 	c.writer = c.createService(svc, "writer")
 	c.Add(c.writer)
 }
 
-func (c *cast) createService(svc func(chan struct{}) error, suffix string) util.ServiceWithError {
-	return util.AsServiceWithError(func(stop chan struct{}) error {
+func (c *cast) createService(svc func(context.Context) error, suffix string) util.ServiceWithError {
+	return util.AsServiceWithError(func(ctx context.Context) error {
 		l.Debugln("Starting", c.name, suffix)
-		err := svc(stop)
+		err := svc(ctx)
 		l.Debugf("Stopped %v %v: %v", c.name, suffix, err)
 		return err
-	})
+	}, fmt.Sprintf("%s/%s", c, suffix))
 }
 
 func (c *cast) Stop() {

lib/beacon/broadcast.go

@@ -7,34 +7,32 @@
 package beacon
 
 import (
+	"context"
 	"net"
 	"time"
 )
 
 func NewBroadcast(port int) Interface {
 	c := newCast("broadcastBeacon")
-	c.addReader(func(stop chan struct{}) error {
-		return readBroadcasts(c.outbox, port, stop)
+	c.addReader(func(ctx context.Context) error {
+		return readBroadcasts(ctx, c.outbox, port)
 	})
-	c.addWriter(func(stop chan struct{}) error {
-		return writeBroadcasts(c.inbox, port, stop)
+	c.addWriter(func(ctx context.Context) error {
+		return writeBroadcasts(ctx, c.inbox, port)
 	})
 	return c
 }
 
-func writeBroadcasts(inbox <-chan []byte, port int, stop chan struct{}) error {
+func writeBroadcasts(ctx context.Context, inbox <-chan []byte, port int) error {
 	conn, err := net.ListenUDP("udp4", nil)
 	if err != nil {
 		l.Debugln(err)
 		return err
 	}
-	done := make(chan struct{})
-	defer close(done)
+	doneCtx, cancel := context.WithCancel(ctx)
+	defer cancel()
 	go func() {
-		select {
-		case <-stop:
-		case <-done:
-		}
+		<-doneCtx.Done()
 		conn.Close()
 	}()
 
@@ -42,7 +40,7 @@ func writeBroadcasts(inbox <-chan []byte, port int, stop chan struct{}) error {
 		var bs []byte
 		select {
 		case bs = <-inbox:
-		case <-stop:
+		case <-doneCtx.Done():
 			return nil
 		}
 
@@ -99,19 +97,17 @@ func writeBroadcasts(inbox <-chan []byte, port int, stop chan struct{}) error {
 	}
 }
 
-func readBroadcasts(outbox chan<- recv, port int, stop chan struct{}) error {
+func readBroadcasts(ctx context.Context, outbox chan<- recv, port int) error {
 	conn, err := net.ListenUDP("udp4", &net.UDPAddr{Port: port})
 	if err != nil {
 		l.Debugln(err)
 		return err
 	}
-	done := make(chan struct{})
-	defer close(done)
+
+	doneCtx, cancel := context.WithCancel(ctx)
+	defer cancel()
 	go func() {
-		select {
-		case <-stop:
-		case <-done:
-		}
+		<-doneCtx.Done()
 		conn.Close()
 	}()
 
@@ -129,7 +125,7 @@ func readBroadcasts(outbox chan<- recv, port int, stop chan struct{}) error {
 		copy(c, bs)
 		select {
 		case outbox <- recv{c, addr}:
-		case <-stop:
+		case <-doneCtx.Done():
 			return nil
 		default:
 			l.Debugln("dropping message")

lib/beacon/multicast.go

@@ -7,6 +7,7 @@
 package beacon
 
 import (
+	"context"
 	"errors"
 	"net"
 	"time"
@@ -16,16 +17,16 @@ import (
 
 func NewMulticast(addr string) Interface {
 	c := newCast("multicastBeacon")
-	c.addReader(func(stop chan struct{}) error {
-		return readMulticasts(c.outbox, addr, stop)
+	c.addReader(func(ctx context.Context) error {
+		return readMulticasts(ctx, c.outbox, addr)
 	})
-	c.addWriter(func(stop chan struct{}) error {
-		return writeMulticasts(c.inbox, addr, stop)
+	c.addWriter(func(ctx context.Context) error {
+		return writeMulticasts(ctx, c.inbox, addr)
 	})
 	return c
 }
 
-func writeMulticasts(inbox <-chan []byte, addr string, stop chan struct{}) error {
+func writeMulticasts(ctx context.Context, inbox <-chan []byte, addr string) error {
 	gaddr, err := net.ResolveUDPAddr("udp6", addr)
 	if err != nil {
 		l.Debugln(err)
@@ -37,13 +38,10 @@ func writeMulticasts(inbox <-chan []byte, addr string, stop chan struct{}) error
 		l.Debugln(err)
 		return err
 	}
-	done := make(chan struct{})
-	defer close(done)
+	doneCtx, cancel := context.WithCancel(ctx)
+	defer cancel()
 	go func() {
-		select {
-		case <-stop:
-		case <-done:
-		}
+		<-doneCtx.Done()
 		conn.Close()
 	}()
 
@@ -57,7 +55,7 @@ func writeMulticasts(inbox <-chan []byte, addr string, stop chan struct{}) error
 		var bs []byte
 		select {
 		case bs = <-inbox:
-		case <-stop:
+		case <-doneCtx.Done():
 			return nil
 		}
 
@@ -84,7 +82,7 @@ func writeMulticasts(inbox <-chan []byte, addr string, stop chan struct{}) error
 			success++
 
 			select {
-			case <-stop:
+			case <-doneCtx.Done():
 				return nil
 			default:
 			}
@@ -96,7 +94,7 @@ func writeMulticasts(inbox <-chan []byte, addr string, stop chan struct{}) error
 	}
 }
 
-func readMulticasts(outbox chan<- recv, addr string, stop chan struct{}) error {
+func readMulticasts(ctx context.Context, outbox chan<- recv, addr string) error {
 	gaddr, err := net.ResolveUDPAddr("udp6", addr)
 	if err != nil {
 		l.Debugln(err)
@@ -108,13 +106,10 @@ func readMulticasts(outbox chan<- recv, addr string, stop chan struct{}) error {
 		l.Debugln(err)
 		return err
 	}
-	done := make(chan struct{})
-	defer close(done)
+	doneCtx, cancel := context.WithCancel(ctx)
+	defer cancel()
 	go func() {
-		select {
-		case <-stop:
-		case <-done:
-		}
+		<-doneCtx.Done()
 		conn.Close()
 	}()
 
@@ -144,7 +139,7 @@ func readMulticasts(outbox chan<- recv, addr string, stop chan struct{}) error {
 	bs := make([]byte, 65536)
 	for {
 		select {
-		case <-stop:
+		case <-doneCtx.Done():
 			return nil
 		default:
 		}