Thread: Adjust checks for whether current thread is the game thread

src/os/os2/os2.cpp

@@ -223,3 +223,4 @@ void PerThreadSetupInit() { }
 bool IsMainThread() { return false; }
 bool IsNonMainThread() { return false; }
 bool IsGameThread() { return false; }
+bool IsNonGameThread() { return false; }

src/os/unix/unix.cpp

@@ -380,6 +380,15 @@ bool IsGameThread()
 {
 #if !defined(NO_THREADS)
 	return game_thread == pthread_self();
+#else
+	return true;
+#endif
+}
+
+bool IsNonGameThread()
+{
+#if !defined(NO_THREADS)
+	return game_thread != pthread_self();
 #else
 	return false;
 #endif

src/os/windows/win32.cpp

@@ -757,6 +757,11 @@ bool IsGameThread()
 	return game_thread_id == GetCurrentThreadId();
 }
 
+bool IsNonGameThread()
+{
+	return game_thread_id != GetCurrentThreadId();
+}
+
 static std::map<DWORD, std::string> _thread_name_map;
 static std::mutex _thread_name_map_mutex;