fix: handle RPC server panic if port is in use (#418)

bootnode/bootnode.go

@@ -70,6 +70,9 @@ func RunBootnode(ctx context.Context, cfg *Config) error {
 		},
 		IsBootnodeOnly: true,
 	})
+	if err != nil {
+		return err
+	}
 
 	log.Infof("starting bootnode with data-dir %s", cfg.DataDir)
 	err = rpcServer.Start()

daemon/swap_daemon.go

@@ -157,6 +157,9 @@ func RunSwapDaemon(ctx context.Context, conf *SwapdConfig) (err error) {
 		RecoveryDB:      sdb.RecoveryDB(),
 		Namespaces:      rpc.AllNamespaces(),
 	})
+	if err != nil {
+		return err
+	}
 
 	log.Infof("starting swapd with data-dir %s", conf.EnvConf.DataDir)
 	err = rpcServer.Start()