From 968035e2c90be895cb7517677b056875060cc229 Mon Sep 17 00:00:00 2001
From: Martin Brodbeck <martin@brodbeck-online.de>
Date: Wed, 4 Oct 2023 10:12:38 +0200
Subject: [PATCH] now sending keepalive pakets

---
 src/main.rs | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 768bfc4..4a26834 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,9 +1,10 @@
 use chrono::{DateTime, Duration, Local};
-use std::{collections::HashMap, net::UdpSocket, thread};
 use log::debug;
+use std::{collections::HashMap, net::UdpSocket, thread};
 
-const MAX_CLIENTS: usize = 10;
 const CLIENT_TIMEOUT: u32 = 300;
+const KEEPALIVE: u64 = 10;
+const MAX_CLIENTS: usize = 10;
 const MY_SPEED: u8 = 30;
 
 fn strip_header(msg: &[u8]) -> Vec<u8> {
@@ -120,9 +121,7 @@ fn main() -> std::io::Result<()> {
     env_logger::init();
 
     let socket = UdpSocket::bind("0.0.0.0:7373")?;
-    socket
-        .set_read_timeout(None)
-        .expect("Could not set read timeout");
+    socket.set_read_timeout(Some(core::time::Duration::from_secs(KEEPALIVE))).expect("Could not set read timeout");
 
     debug!("Morserino chat server started.");
 
@@ -130,7 +129,21 @@ fn main() -> std::io::Result<()> {
 
     loop {
         let mut buf = [0; 64];
-        let (number_of_bytes, src_addr) = socket.recv_from(&mut buf).expect("Didn't receive data");
+
+        // Waiting for incoming pakets. Otherwise, after timeout, send keepalive paket
+        let result = socket.recv_from(&mut buf);
+        let (number_of_bytes, src_addr) = match result {
+            Ok((num, s)) => (num, s),
+            Err(_) => {
+                debug!("Sending keepalive pakets …");
+                for rec in &receivers2 {
+                    socket.send_to(b"", rec.0).unwrap();
+                }
+                continue;
+            },
+        };
+
+
         let client_addr = src_addr.to_string();
         let speed = buf[1] >> 2;
         let data = &buf[0..number_of_bytes];