refactor: cleanup

src-tauri/src/proxy_server.rs

@@ -16,7 +16,6 @@ use std::sync::atomic::{AtomicU64, Ordering};
 use std::sync::Arc;
 use std::task::{Context, Poll};
 use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt, ReadBuf};
-use tokio::net::TcpListener;
 use tokio::net::TcpStream;
 
 /// Combined read+write trait for tunnel target streams, allowing
@@ -1232,8 +1231,49 @@ pub async fn run_proxy_server(config: ProxyConfig) -> Result<(), Box<dyn std::er
 
   log::error!("Attempting to bind proxy server to {}", bind_addr);
 
-  // Bind to the port
-  let listener = TcpListener::bind(bind_addr).await?;
+  // Bind to the port. Use SO_REUSEADDR so that a freshly-restarted worker
+  // can bind a port that the previous worker left in TIME_WAIT, and retry
+  // briefly to absorb transient races with the OS releasing the socket.
+  let listener = {
+    let mut attempts: u32 = 0;
+    loop {
+      let socket = tokio::net::TcpSocket::new_v4()?;
+      let _ = socket.set_reuseaddr(true);
+      match socket.bind(bind_addr) {
+        Ok(()) => match socket.listen(1024) {
+          Ok(l) => break l,
+          Err(e) if attempts < 5 => {
+            attempts += 1;
+            let delay = std::time::Duration::from_millis(200 * u64::from(attempts));
+            log::warn!(
+              "listen() on {} failed (attempt {}/5): {}, retrying in {}ms",
+              bind_addr,
+              attempts,
+              e,
+              delay.as_millis()
+            );
+            tokio::time::sleep(delay).await;
+          }
+          Err(e) => {
+            return Err(format!("Failed to listen on {bind_addr} after 5 attempts: {e}").into())
+          }
+        },
+        Err(e) if attempts < 5 => {
+          attempts += 1;
+          let delay = std::time::Duration::from_millis(200 * u64::from(attempts));
+          log::warn!(
+            "bind() on {} failed (attempt {}/5): {}, retrying in {}ms",
+            bind_addr,
+            attempts,
+            e,
+            delay.as_millis()
+          );
+          tokio::time::sleep(delay).await;
+        }
+        Err(e) => return Err(format!("Failed to bind {bind_addr} after 5 attempts: {e}").into()),
+      }
+    }
+  };
   let actual_port = listener.local_addr()?.port();
 
   log::error!("Successfully bound to port {}", actual_port);
@@ -1295,52 +1335,54 @@ pub async fn run_proxy_server(config: ProxyConfig) -> Result<(), Box<dyn std::er
 
     loop {
       interval.tick().await;
-      if let Some(tracker) = get_traffic_tracker() {
-        let (sent, recv, requests) = tracker.get_snapshot();
-        let current_bytes = sent + recv;
-        let time_since_activity = last_activity_time.elapsed();
-        let time_since_flush = last_flush_time.elapsed();
-        let has_traffic = current_bytes > 0 || requests > 0;
+      // Catch panics so a poisoned lock or unexpected error inside
+      // flush_to_disk doesn't abort the flush task and leave stats
+      // unwritten for the lifetime of the worker. The captured state
+      // is all Copy or atomic-assignment, so AssertUnwindSafe is sound.
+      let result = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
+        if let Some(tracker) = get_traffic_tracker() {
+          let (sent, recv, requests) = tracker.get_snapshot();
+          let current_bytes = sent + recv;
+          let time_since_activity = last_activity_time.elapsed();
+          let time_since_flush = last_flush_time.elapsed();
+          let has_traffic = current_bytes > 0 || requests > 0;
 
-        // Determine flush frequency based on activity
-        // When active: flush every 5 seconds
-        // When idle: flush every 30 seconds
-        let desired_interval_secs =
-          if has_traffic || time_since_activity < std::time::Duration::from_secs(30) {
-            5u64
-          } else {
-            30u64
-          };
+          let desired_interval_secs =
+            if has_traffic || time_since_activity < std::time::Duration::from_secs(30) {
+              5u64
+            } else {
+              30u64
+            };
 
-        // Update interval if needed
-        if desired_interval_secs != current_interval_secs {
-          current_interval_secs = desired_interval_secs;
-          interval = tokio::time::interval(tokio::time::Duration::from_secs(desired_interval_secs));
-        }
+          if desired_interval_secs != current_interval_secs {
+            current_interval_secs = desired_interval_secs;
+            interval =
+              tokio::time::interval(tokio::time::Duration::from_secs(desired_interval_secs));
+          }
 
-        // Only flush if enough time has passed since last flush
-        let flush_interval = std::time::Duration::from_secs(desired_interval_secs);
-        let should_flush = time_since_flush >= flush_interval;
+          let flush_interval = std::time::Duration::from_secs(desired_interval_secs);
+          let should_flush = time_since_flush >= flush_interval;
 
-        if should_flush {
-          match tracker.flush_to_disk() {
-            Ok(Some((sent, recv))) => {
-              // Successful flush with data
-              last_flush_time = std::time::Instant::now();
-              if sent > 0 || recv > 0 {
-                last_activity_time = std::time::Instant::now();
+          if should_flush {
+            match tracker.flush_to_disk() {
+              Ok(Some((sent, recv))) => {
+                last_flush_time = std::time::Instant::now();
+                if sent > 0 || recv > 0 {
+                  last_activity_time = std::time::Instant::now();
+                }
+              }
+              Ok(None) => {
+                last_flush_time = std::time::Instant::now();
+              }
+              Err(e) => {
+                log::error!("Failed to flush traffic stats: {}", e);
               }
-            }
-            Ok(None) => {
-              // No data to flush - this is normal
-              last_flush_time = std::time::Instant::now();
-            }
-            Err(e) => {
-              log::error!("Failed to flush traffic stats: {}", e);
-              // Don't update flush time on error - retry sooner
             }
           }
         }
+      }));
+      if let Err(panic) = result {
+        log::error!("Panic caught in proxy traffic flush task; continuing: {panic:?}");
       }
     }
   });