Finally made fetch happen

src/fetch_stage.rs

@@ -0,0 +1,31 @@
+//! The `fetch_stage` batches input from a UDP socket and sends it to a channel.
+
+use packet;
+use std::net::UdpSocket;
+use std::sync::Arc;
+use std::sync::atomic::AtomicBool;
+use std::sync::mpsc::channel;
+use std::thread::JoinHandle;
+use streamer;
+
+pub struct FetchStage {
+    pub packet_receiver: streamer::PacketReceiver,
+    pub thread_hdl: JoinHandle<()>,
+}
+
+impl FetchStage {
+    pub fn new(
+        socket: UdpSocket,
+        exit: Arc<AtomicBool>,
+        packet_recycler: packet::PacketRecycler,
+    ) -> Self {
+        let (packet_sender, packet_receiver) = channel();
+        let thread_hdl =
+            streamer::receiver(socket, exit.clone(), packet_recycler.clone(), packet_sender);
+
+        FetchStage {
+            packet_receiver,
+            thread_hdl,
+        }
+    }
+}