fix(Windows): Handle thread WM_QUIT and fix message dispatch

src/tray_windows.c

@@ -256,14 +256,26 @@ int tray_init(struct tray *tray) {
 
 int tray_loop(int blocking) {
   MSG msg;
+  int has_message = 0;
+
+  // Use the thread queue and only dispatch when a message was actually retrieved.
+  // This ensures WM_QUIT is observed and avoids dispatching an uninitialized MSG.
   if (blocking) {
-    GetMessage(&msg, hwnd, 0, 0);
+    has_message = GetMessage(&msg, NULL, 0, 0);
+    if (has_message <= 0) {
+      return -1;
+    }
   } else {
-    PeekMessage(&msg, hwnd, 0, 0, PM_REMOVE);
+    has_message = PeekMessage(&msg, NULL, 0, 0, PM_REMOVE);
+    if (has_message == 0) {
+      return 0;
+    }
   }
+
   if (msg.message == WM_QUIT) {
     return -1;
   }
+
   TranslateMessage(&msg);
   DispatchMessage(&msg);
   return 0;

tests/unit/test_tray.cpp

@@ -235,6 +235,28 @@ TEST_F(TrayTest, TestTrayLoop) {
   EXPECT_EQ(result, 0);
 }
 
+#if defined(TRAY_WINAPI)
+TEST_F(TrayTest, TestTrayLoopHandlesThreadQuitMessage) {
+  int initResult = tray_init(&testTray);
+  trayRunning = (initResult == 0);
+  ASSERT_EQ(initResult, 0);
+
+  // WM_QUIT is posted to the thread queue, not to a specific window.
+  PostQuitMessage(0);
+
+  bool sawQuit = false;
+  for (int i = 0; i < 200; ++i) {
+    if (tray_loop(0) == -1) {
+      sawQuit = true;
+      break;
+    }
+    std::this_thread::sleep_for(std::chrono::milliseconds(1));
+  }
+
+  EXPECT_TRUE(sawQuit);
+}
+#endif
+
 TEST_F(TrayTest, TestTrayUpdate) {
   int initResult = tray_init(&testTray);
   trayRunning = (initResult == 0);