cmd: fix quit channel goroutine leak

cmd/devp2p/crawl.go

@@ -45,7 +45,7 @@ func newCrawler(input nodeSet, disc *discover.UDPv4, iters ...enode.Iterator) *c
 		iters:     iters,
 		inputIter: enode.IterNodes(input.nodes()),
 		ch:        make(chan *enode.Node),
-		closed:    make(chan struct{}),
+		closed:    make(chan struct{}, 1),
 	}
 	c.iters = append(c.iters, c.inputIter)
 	// Copy input to output initially. Any nodes that fail validation

cmd/utils/cmd.go

@@ -89,7 +89,7 @@ func ImportChain(chain *core.BlockChain, fn string) error {
 	// Watch for Ctrl-C while the import is running.
 	// If a signal is received, the import will stop at the next batch.
 	interrupt := make(chan os.Signal, 1)
-	stop := make(chan struct{})
+	stop := make(chan struct{}, 1)
 	signal.Notify(interrupt, syscall.SIGINT, syscall.SIGTERM)
 	defer signal.Stop(interrupt)
 	defer close(interrupt)

cmd/wnode/main.go

@@ -175,7 +175,7 @@ func echo() {
 func initialize() {
 	log.Root().SetHandler(log.LvlFilterHandler(log.Lvl(*argVerbosity), log.StreamHandler(os.Stderr, log.TerminalFormat(false))))
 
-	done = make(chan struct{})
+	done = make(chan struct{}, 1)
 	var peers []*enode.Node
 	var err error