refactor: move tcp connection in main to new function and use by Controller

src/lib.rs

 pub mod openflow;
 
 pub mod etherparser;
+
+mod tcp_listener;
\ No newline at end of file

src/main.rs

-use std::io::Read;
-use std::net::TcpListener;
-use tenjin::openflow::events::packet_in::PacketInEvent;
-use tenjin::openflow::messages::{OfpMsg, Openflow10};
-use tenjin::openflow::traiter::OfpMsgEvent;
-use tenjin::openflow::{Controller, OfpHeader};
+use tenjin::openflow::messages::Openflow10;
+use tenjin::openflow::Controller;
 
 extern crate byteorder;
 
 fn main() -> Result<(), std::io::Error> {
     let mut controller = Controller::new(Openflow10::new());
-
-    let listener = TcpListener::bind(("127.0.0.1", 6633)).unwrap();
-    let mut buf = vec![0u8; 8];
-    for stream in listener.incoming() {
-        println!("{:?}", stream);
-        match stream {
-            Ok(mut stream) => {
-                // std::thread::spawn(move || {
-                println!("=================== connection =======================");
-
-                // after tcp is connected, it will send hello message
-                controller.hello(&mut stream);
-
-                // loop for receive data
-                loop {
-                    // first receive with Openflow header 64 bit to buf
-                    match stream.read(&mut buf) {
-                        Ok(v) if v > 0 => {
-                            let packet = OfpHeader::parse(&buf);
-                            // length_payload is var to receive payload if the packet has
-                            // and assign size by length
-                            let length_payload = packet.size();
-                            let mut payload = vec![0u8; length_payload];
-                            stream.read(&mut payload)?;
-                            let message = controller.ofp.msg_parse(packet.message as u16);
-
-                            match message {
-                                // 0 is Hello message
-                                OfpMsg::Hello => {
-                                    // after get Hello, send fetureReq
-                                    controller.fetures_req(packet.xid, &mut stream);
-                                    println!("Hello event");
-                                }
-                                OfpMsg::PacketIn => {
-                                    controller.packet_in(
-                                        packet.xid,
-                                        PacketInEvent::parse(&payload),
-                                        &mut stream,
-                                    );
-                                    println!("PacketIn event");
-                                }
-                                _ => {
-                                    println!("others message");
-                                }
-                            }
-                        }
-                        Ok(_) | Err(_) => break,
-                    }
-                }
-                println!("======================================================");
-
-                // });
-            }
-            Err(_) => {
-                // connection failed
-                panic!("Connection failed")
-            }
-        }
-    }
+    controller.listener("127.0.0.1:6633");
     Ok(())
 }

src/openflow/controller.rs

-use std::{collections::HashMap, io::Write, net::TcpStream};
+use std::{
+    collections::HashMap,
+    io::{Read, Write},
+    net::TcpStream,
+};
+
+use crate::tcp_listener::tcp_listener_handler;
 
 use super::{
     events::PacketInEvent,
-    messages::traiter::{MessageMarshal, OfpMsgEvent},
+    messages::{
+        traiter::{MessageMarshal, OfpMsgEvent},
+        OfpMsg,
+    },
+    OfpHeader,
 };
 
 pub struct Controller<OME: OfpMsgEvent> {
@@ -23,6 +33,26 @@ impl<OME: OfpMsgEvent> Controller<OME> {
         }
     }
 
+    pub fn listener(&mut self, address: &str) {
+        tcp_listener_handler(self, address);
+    }
+
+    pub fn request_handler(&mut self, buf: &mut Vec<u8>, stream: &mut TcpStream) {
+        let ofp_header = OfpHeader::parse(&buf);
+        let mut payload = vec![0u8; ofp_header.pkt_size()];
+        let _ = stream.read(&mut payload);
+        let message = self.ofp.msg_parse(ofp_header.message as u16);
+        match message {
+            OfpMsg::Hello => self.send_msg(self.ofp.fetures_req(), ofp_header.xid, stream),
+            OfpMsg::FeaturesReq => todo!(),
+            OfpMsg::PacketIn => {
+                self.packet_in_handler(ofp_header.xid, PacketInEvent::parse(&payload), stream);
+            }
+            OfpMsg::FlowMod => todo!(),
+            OfpMsg::NotFound => todo!(),
+        }
+    }
+
     pub fn send_msg<T: MessageMarshal>(&self, msg: T, xid: u32, stream: &mut TcpStream) {
         let mut header_bytes: Vec<u8> = Vec::new();
         let mut body_bytes: Vec<u8> = Vec::new();
@@ -49,7 +79,7 @@ impl<OME: OfpMsgEvent> Controller<OME> {
         self.send_msg(fetreq_msg, xid, stream);
     }
 
-    pub fn packet_in(&mut self, xid: u32, packetin: PacketInEvent, stream: &mut TcpStream) {
+    pub fn packet_in_handler(&mut self, xid: u32, packetin: PacketInEvent, stream: &mut TcpStream) {
         let ether = packetin.payload;
         self.mac_to_port.insert(ether.mac_src, packetin.port);
     }

src/openflow/header.rs

@@ -10,7 +10,10 @@ pub struct OfpHeader {
 }
 
 impl OfpHeader {
-    pub fn size(&self) -> usize {
+    pub fn header_size(&self) -> usize {
+        size_of::<OfpHeader>()
+    }
+    pub fn pkt_size(&self) -> usize {
         return self.length as usize - size_of::<OfpHeader>();
     }
     pub fn new(version: u8, message: u8, length: u16, xid: u32) -> Self {

src/tcp_listener.rs

+use std::{io::Read, net::TcpListener};
+
+use crate::openflow::{traiter::OfpMsgEvent, Controller};
+
+pub fn tcp_listener_handler<OME: OfpMsgEvent>(controller: &mut Controller<OME>, address: &str) {
+    let listener = TcpListener::bind(address).unwrap();
+    /*
+     * buffer with 8 length that only support openflow 1.0
+     * I will make it support others version soon.
+     */
+    let mut buffer = vec![0u8; 8];
+    for stream in listener.incoming() {
+        match stream {
+            Ok(mut stream) => {
+                controller.hello(&mut stream);
+                loop {
+                    match stream.read(&mut buffer) {
+                        Ok(v) if v > 0 => {
+                            controller.request_handler(&mut buffer, &mut stream);
+                        }
+                        Ok(_) | Err(_) => panic!("Connection failed!"),
+                    }
+                }
+            }
+            Err(_) => todo!(),
+        }
+    }
+}