Commit 9c95c2491cafb85de6ce09c653a5754f0d4cb2f3
2021-11-08T20:01:56
x11: Use XCheckIfEvent() instead of XNextEvent() for thread-safety A racing reader could read from our fd between SDL_IOReady()/X11_Pending() and our call to XNextEvent() which will cause XNextEvent() to block for more data. Avoid this by using XCheckIfEvent() which will never block. This also fixes a bug where we could poll() for data, even when events were already read and pending in the queue. Unlike the Wayland implementation, this isn't totally thread-safe because nothing prevents a racing reader from reading events into the queue between our XCheckIfEvent() and SDL_IOReady() calls, but I think this is the best we can do with Xlib.