add infra code

infra/enginewhy-lb.rs

@@ -0,0 +1,68 @@
+use rperf3::{Server, Config};
+use std::net::{TcpListener, TcpStream};
+use std::thread;
+use std::io::{Read, Write};
+use std::env;
+use tokio::task;
+
+async fn start_iperf_server() -> Result<(), Box<dyn std::error::Error>> {
+    let config = Config::server(5001);
+    let server = Server::new(config);
+    server.run().await?;
+    Ok(())
+}
+
+fn handle_connection(mut stream: TcpStream) -> std::io::Result<()> {
+    loop {
+        let mut buffer = [0u8; 512];
+        let bytes_read = stream.read(&mut buffer)?; 
+        let received = String::from_utf8_lossy(&buffer[..bytes_read]);
+        println!("Received: {}", received);
+    }
+    Ok(())
+}
+
+fn start_tcp_server(addr: &str) -> std::io::Result<()> {
+    let listener = TcpListener::bind(addr)?;
+    println!("TCP server listening on {}", addr);
+    let mut handles = Vec::new();
+    for stream in listener.incoming() {
+        match stream {
+            Ok(stream) => {
+                let handle = thread::spawn(move || {
+                    if let Err(e) = handle_connection(stream) {
+                        eprintln!("connection handler error: {}", e);
+                    }
+                });
+                handles.push(handle);
+            }
+            Err(e) => eprintln!("incoming connection failed: {}", e),
+        }
+    }
+
+    // When the incoming stream iterator ends (listener closed), join all handlers.
+    for h in handles {
+        let _ = h.join();
+    }
+    Ok(())
+}
+
+#[tokio::main]
+async fn main() {
+    // Choose IP based on `--localhost` flag for debugging
+    let use_localhost = env::args().any(|a| a == "--localhost");
+    let ip = if use_localhost { "127.0.0.1" } else { "192.67.67.67" };
+    let tcp_addr = format!("{}:8080", ip);
+
+    let iperf_server = task::spawn(async {
+        start_iperf_server().await;
+    });
+
+    let tcp_ip = tcp_addr.clone();
+    let tcp_server = thread::spawn(move || {
+        start_tcp_server(&tcp_ip).unwrap();
+    });
+
+    iperf_server.await.unwrap();
+    tcp_server.join().unwrap();
+}