From 7c2ab2aa6001f650bea4d83e9ae7b7d124b880fd Mon Sep 17 00:00:00 2001
From: Vantz Stockwell <vstockwell@predator-mini.local>
Date: Wed, 25 Mar 2026 12:16:50 -0400
Subject: [PATCH] =?UTF-8?q?fix:=20error=20watcher=20crash=20=E2=80=94=20to?=
 =?UTF-8?q?kio::spawn=20without=20runtime=20context?=
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Same root cause as the PTY crash (v1.2.6): tokio::spawn called from
Tauri setup hook without a tokio runtime guard. Switched error watcher
to std::thread::spawn. Also wrapped both error watcher and MCP server
spawn in individual catch_unwind blocks so neither can crash the app.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 src-tauri/src/lib.rs               | 21 ++++++++++++++-------
 src-tauri/src/mcp/error_watcher.rs |  4 ++--
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index 2f2835f..5116e80 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -153,17 +153,24 @@ pub fn run() {
                     let (ssh, rdp, sftp, scrollback, watcher) = state;
                     let _ = write_log(&log_file, "Setup: cloned services OK");
 
+                    // Error watcher — std::thread, no tokio needed
                     let app_handle = app.handle().clone();
-                    mcp::error_watcher::start_error_watcher(watcher, scrollback.clone(), app_handle);
+                    let _ = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
+                        mcp::error_watcher::start_error_watcher(watcher, scrollback.clone(), app_handle);
+                    }));
                     let _ = write_log(&log_file, "Setup: error watcher started");
 
+                    // MCP HTTP server — needs async runtime
                     let log_file2 = log_file.clone();
-                    tauri::async_runtime::spawn(async move {
-                        match mcp::server::start_mcp_server(ssh, rdp, sftp, scrollback).await {
-                            Ok(port) => { let _ = write_log(&log_file2, &format!("MCP server started on localhost:{}", port)); }
-                            Err(e) => { let _ = write_log(&log_file2, &format!("MCP server FAILED: {}", e)); }
-                        }
-                    });
+                    let _ = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
+                        tauri::async_runtime::spawn(async move {
+                            match mcp::server::start_mcp_server(ssh, rdp, sftp, scrollback).await {
+                                Ok(port) => { let _ = write_log(&log_file2, &format!("MCP server started on localhost:{}", port)); }
+                                Err(e) => { let _ = write_log(&log_file2, &format!("MCP server FAILED: {}", e)); }
+                            }
+                        });
+                    }));
+                    let _ = write_log(&log_file, "Setup: MCP spawn dispatched");
                 }
                 Err(panic) => {
                     let msg = if let Some(s) = panic.downcast_ref::<String>() {
diff --git a/src-tauri/src/mcp/error_watcher.rs b/src-tauri/src/mcp/error_watcher.rs
index e574c05..e5bc6a7 100644
--- a/src-tauri/src/mcp/error_watcher.rs
+++ b/src-tauri/src/mcp/error_watcher.rs
@@ -99,9 +99,9 @@ pub fn start_error_watcher(
     scrollback: ScrollbackRegistry,
     app_handle: AppHandle,
 ) {
-    tokio::spawn(async move {
+    std::thread::spawn(move || {
         loop {
-            tokio::time::sleep(std::time::Duration::from_secs(2)).await;
+            std::thread::sleep(std::time::Duration::from_secs(2));
 
             let alerts = watcher.scan(&scrollback);
             for (session_id, line) in alerts {