Fix broadcast collection: UDP reader blocks until deadline, 500ms timeout everywhere

lib/client/udp.go

@@ -118,17 +118,20 @@ func (t *udpTransport) SetReadTimeout(timeout time.Duration) {
 }
 
 func (t *udpTransport) Reader() io.Reader {
-	for {
+	return t
+}
+
+func (t *udpTransport) Read(p []byte) (int, error) {
 	if t.buf.Len() > 0 {
-			return &t.buf
+		return t.buf.Read(p)
 	}
 	pkt := make([]byte, 1500)
 	n, err := t.conn.Read(pkt)
 	if err != nil {
-			return &t.buf
+		return 0, err
 	}
 	t.buf.Write(pkt[:n])
-	}
+	return t.buf.Read(p)
 }
 
 func (t *udpTransport) Broadcast() bool { return t.broadcast }