fix(web_ui): cap bind_with_retry at 12 attempts, then return AddrInUse

hive-ag3nt/src/web_ui/mod.rs

@@ -192,12 +192,16 @@ fn bind_unix(path: &Path) -> Result<tokio::net::UnixListener> {
     Ok(listener)
 }
 
-/// Bind a TCP listener with `SO_REUSEADDR` set, retrying on
+/// Maximum bind attempts before `bind_with_retry` gives up on `AddrInUse`.
-/// `AddrInUse` indefinitely with exponential backoff capped at 2s.
+const MAX_BIND_ATTEMPTS: u32 = 12;
-/// First 12 attempts log at WARN; subsequent attempts log at INFO so
+
-/// a long-held stale socket doesn't flood the journal.
+/// Bind a TCP listener with `SO_REUSEADDR` set, retrying on `AddrInUse` with
+/// exponential backoff capped at 2s, up to [`MAX_BIND_ATTEMPTS`] attempts. If
+/// the port is still held after the final attempt, returns the `AddrInUse`
+/// error rather than looping forever (a genuine collision needs the operator,
+/// not an unbounded wait).
 ///
-/// Uncapped retry + dashboard-banner-on-real-collision rationale:
+/// Retry rationale + dashboard-banner-on-real-collision:
 /// see [`docs/web-ui/shape.md::Listener bind`](../../../docs/web-ui/shape.md).
 async fn bind_with_retry(addr: SocketAddr, label: &str) -> Result<tokio::net::TcpListener> {
     let mut delay_ms = 250u64;
@@ -215,17 +219,15 @@ async fn bind_with_retry(addr: SocketAddr, label: &str) -> Result<tokio::net::Tc
             }
             Err(e) if e.kind() == std::io::ErrorKind::AddrInUse => {
                 let attempt = attempts + 1;
-                if attempt <= 12 {
+                if attempt >= MAX_BIND_ATTEMPTS {
-                    tracing::warn!(
+                    return Err(e).with_context(|| {
-                        %addr, attempt,
+                        format!("bind {label} on {addr}: still AddrInUse after {attempt} attempts")
-                        "{label}: AddrInUse, retrying in {delay_ms}ms"
+                    });
-                    );
-                } else {
-                    tracing::info!(
-                        %addr, attempt,
-                        "{label}: AddrInUse still holding, retrying in {delay_ms}ms"
-                    );
                 }
+                tracing::warn!(
+                    %addr, attempt,
+                    "{label}: AddrInUse, retrying in {delay_ms}ms"
+                );
                 tokio::time::sleep(std::time::Duration::from_millis(delay_ms)).await;
                 attempts += 1;
                 delay_ms = (delay_ms * 2).min(2000);