From b0944662fa35045918d6803cbe51ec5316871847 Mon Sep 17 00:00:00 2001
From: LGUG2Z <LGUG2Z@fastmail.com>
Date: Sun, 13 Oct 2024 14:41:46 -0700
Subject: [PATCH] fix(wm): add cmd thread lock acquisition timeouts

After some investigation by @alex-ds13 on Discord it looks like there
are times where attempting to gain a lock on the WindowManager inside of
read_commands_uds results in the thread becoming blocked when it's not
possible to obtain the lock.

Instead of waiting indefinitely for a lock, this change ensures that we
will wait for at most 1 second before discarding the message so that the
command listener loop can continue.

Warning logs have been added to inform when a message has been dropped
as a result of lock acquisition failure.
---
 komorebi/src/process_command.rs | 35 ++++++++++++++++++++-------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/komorebi/src/process_command.rs b/komorebi/src/process_command.rs
index 0cfa013e..50593c66 100644
--- a/komorebi/src/process_command.rs
+++ b/komorebi/src/process_command.rs
@@ -1619,22 +1619,29 @@ pub fn read_commands_uds(wm: &Arc<Mutex<WindowManager>>, mut stream: UnixStream)
     for line in reader.lines() {
         let message = SocketMessage::from_str(&line?)?;
 
-        let mut wm = wm.lock();
-
-        if wm.is_paused {
-            return match message {
-                SocketMessage::TogglePause
-                | SocketMessage::State
-                | SocketMessage::GlobalState
-                | SocketMessage::Stop => Ok(wm.process_command(message, &mut stream)?),
-                _ => {
-                    tracing::trace!("ignoring while paused");
-                    Ok(())
+        match wm.try_lock_for(Duration::from_secs(1)) {
+            None => {
+                tracing::warn!(
+                    "could not acquire window manager lock, not processing message: {message}"
+                );
+            }
+            Some(mut wm) => {
+                if wm.is_paused {
+                    return match message {
+                        SocketMessage::TogglePause
+                        | SocketMessage::State
+                        | SocketMessage::GlobalState
+                        | SocketMessage::Stop => Ok(wm.process_command(message, &mut stream)?),
+                        _ => {
+                            tracing::trace!("ignoring while paused");
+                            Ok(())
+                        }
+                    };
                 }
-            };
-        }
 
-        wm.process_command(message.clone(), &mut stream)?;
+                wm.process_command(message.clone(), &mut stream)?;
+            }
+        }
     }
 
     Ok(())