fix(windows/lib.rs): use a single-threaded Tokio runtime to avoid new EnterGuard ordering issues

Author: Gioee

src/lib.rs

@@ -23,7 +23,11 @@ static GLOBAL_CLIENT: OnceLock<Mutex<Option<McpClient>>> = OnceLock::new();
 /// Get or create the global Tokio runtime
 fn get_runtime() -> &'static tokio::runtime::Runtime {
     GLOBAL_RUNTIME.get_or_init(|| {
-        tokio::runtime::Runtime::new().expect("Failed to create Tokio runtime")
+        // Create a simple single-threaded runtime to avoid Windows issues
+        tokio::runtime::Builder::new_current_thread()
+            .enable_all()
+            .build()
+            .expect("Failed to create Tokio runtime")
     })
 }
 
@@ -151,11 +155,10 @@ pub extern "C" fn mcp_connect(
     };
 
     let use_sse = legacy_sse != 0;
-    let runtime = get_runtime();
 
     let (result, maybe_service) = if use_sse {
         // Use SSE transport (legacy) with optional custom headers
-        runtime.block_on(async {
+        get_runtime().block_on(async {
             // Create HTTP client with optional custom headers
             let mut client_builder = reqwest::Client::builder();
             if let Some(ref headers_map) = headers_map {
@@ -241,7 +244,7 @@ pub extern "C" fn mcp_connect(
         })
     } else {
         // Use streamable HTTP transport (default) with optional custom headers
-        runtime.block_on(async {
+        get_runtime().block_on(async {
             // For Streamable HTTP, we need to extract the Authorization header specifically
             // since it has a dedicated field, and we'll use a custom HTTP client for other headers
             let auth_header_value = headers_map.as_ref().and_then(|m| m.get("Authorization")).map(|s| s.clone());
@@ -369,8 +372,7 @@ pub extern "C" fn mcp_list_tools(_client_ptr: *mut McpClient) -> *mut c_char {
         }
     };
 
-    let runtime = get_runtime();
-    let result = runtime.block_on(async {
+    let result = get_runtime().block_on(async {
         let service_guard = client.service.lock().unwrap();
         let service = match service_guard.as_ref() {
             Some(s) => s,
@@ -464,8 +466,7 @@ pub extern "C" fn mcp_call_tool(
         }
     };
 
-    let runtime = get_runtime();
-    let result = runtime.block_on(async {
+    let result = get_runtime().block_on(async {
         let service_guard = client.service.lock().unwrap();
         let service = match service_guard.as_ref() {
             Some(s) => s,