refactor: replace tokio oneshot channel with crossbeam channel

- remove tokio dependency

Author: robinohs

Cargo.lock

@@ -61,7 +61,6 @@ spin_sleep = "1.3.1"
 tempfile = "3.20.0"
 thiserror = "2.0.12"
 thread-priority = "1.2.0"
-tokio = { version = "1.45.1", features = ["sync"] }
 uom = { version = "0.37.0", features = ["si", "serde", "u64"] }
 
 [build-dependencies]

Cargo.toml

@@ -6,8 +6,8 @@ use std::{
     time::Duration,
 };
 
+use crossbeam::channel::unbounded;
 use log::warn;
-use tokio::sync::oneshot;
 
 use crate::{cli::opt::StartArgs, commands::utils, phork::namespace::NS_NAME_LINK, runtime::Runtime};
 
@@ -23,19 +23,16 @@ pub(crate) fn run(start_args: StartArgs) -> eyre::Result<()> {
     let reconfiguration_delay = Duration::from_micros(micros_reconfiguration_delay);
 
     // set up Ctrl-C handler for cleanup before exit
-    let (tx, rx) = oneshot::channel::<()>();
-    let mut tx = Option::Some(tx);
+    let (tx, rx) = unbounded::<()>();
     let exiting = Arc::new(AtomicBool::new(false));
     ctrlc::set_handler(move || {
         if exiting.load(Ordering::Relaxed) {
             warn!("Ctrl-C received twice, exiting ungracefully. This may leave the network environment in an inconsistent state.");
             std::process::exit(1);
         } else {
-            if let Some(tx) = tx.take() {
-                tx.send(()).unwrap_or_else(|_| {
-                    eprintln!("Failed to send shutdown signal.");
-                });
-            }
+            tx.send(()).unwrap_or_else(|_| {
+                eprintln!("Failed to send shutdown signal.");
+            });
             exiting.store(true, Ordering::Relaxed);
         }
     })

src/commands/start.rs

@@ -1,5 +1,6 @@
+use crossbeam::channel::Receiver;
 use eyre::{bail, OptionExt, Result};
-use log::{debug, info};
+use log::{debug, error, info};
 use pnet::datalink::{self, Channel, ChannelType, Config, NetworkInterface};
 use std::{
     collections::HashMap,
@@ -10,7 +11,6 @@ use std::{
     time::{Duration, Instant, SystemTime, UNIX_EPOCH},
 };
 use tempfile::NamedTempFile;
-use tokio::sync::oneshot::Receiver;
 use uom::si::information::byte;
 
 use crate::{
@@ -150,11 +150,11 @@ impl Runtime {
 
         // Handle shutdown signal
         // This thread will block until a shutdown signal is received.
-        thread::spawn(move || {
-            stop_rx.blocking_recv().unwrap_or_else(|_| {
-                eprintln!("Failed to receive shutdown signal.");
-            });
-            info!("Received shutdown signal, stopping phantomlink...");
+        thread::spawn(move || match stop_rx.recv() {
+            Ok(_) => info!("Received shutdown signal, stopping phantomlink..."),
+            Err(e) => {
+                error!("Error receiving shutdown signal: {}", e);
+            }
         })
         .join()
         .unwrap();