dnsx/transport: on stopAll, stop & clear all transports

Author: ignoramous

intra/dnsx/transport.go

@@ -212,9 +212,9 @@ func NewResolver(pctx context.Context, fakeaddrs string, dtr x.DNSTransport, l x
 	} else {
 		ctr := NewCachingTransport(tr, ttl10m)
 		r.Lock()
-		r.transports[tr.ID().V()] = tr // regular
+		r.transports[idstr(tr)] = tr // regular
 		if ctr != nil {
-			r.transports[ctr.ID().V()] = ctr // cached
+			r.transports[idstr(ctr)] = ctr // cached
 		} else {
 			log.W("dns: no caching transport for %s", tr.ID())
 		}
@@ -918,7 +918,7 @@ func (r *resolver) accept(c io.ReadWriteCloser, uid string) {
 // StopAll stops all transports and closes the resolver.
 func (r *resolver) StopAll() {
 	r.once.Do(func() {
-		core.Go("r.onStop", func() { r.listener.OnDNSStopped() })
+		defer core.Go("r.onStop", func() { r.listener.OnDNSStopped() })
 		r.done()
 
 		if dc, err := r.dcProxy(); err == nil {
@@ -929,17 +929,29 @@ func (r *resolver) StopAll() {
 			_ = p.Stop()
 		}
 
+		// Stop all transports in a separate goroutine to avoid blocking
+		core.Go("r.stopAllTransports", func() {
+			r.Lock()
+			for _, tr := range r.transports {
+				_ = tr.Stop()
+				// r.gateway.onStopped(id) is not required
+				// as the entire setup is closed and going away
+			}
+			clear(r.transports)
+			r.Unlock()
+		})
+
 		close(r.smms) // close listener chan
 	})
 }
 
 func (r *resolver) all() []Transport {
 	r.RLock()
+	defer r.RUnlock()
 	out := make([]Transport, 0, len(r.transports))
 	for _, t := range r.transports {
 		out = append(out, t)
 	}
-	r.RUnlock()
 	return out
 }