glx: Increment dpy->request before issuing an error that had no request

This ensures the sequence number is unique and recent enough for callers
of `glXQueryDrawable` using `XNextRequest` to selectively trap errors.
The same approach is already used in `glXCreateContextAttribsARB`.

Suggested-by: Sebastian Keller <skeller@gnome.org>
Related-to: https://gitlab.gnome.org/GNOME/mutter/-/issues/3007
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25173>

diff --git a/src/glx/glx_pbuffer.c b/src/glx/glx_pbuffer.c
index 0b3cdfa..d95a3e9 100644 (file)
--- a/src/glx/glx_pbuffer.c
+++ b/src/glx/glx_pbuffer.c
@@ -239,6 +239,7 @@ __glXGetDrawableAttribute(Display * dpy, GLXDrawable drawable,
     *     generated."
     */
    if (drawable == 0) {
+      XNoOp(dpy);
       __glXSendError(dpy, GLXBadDrawable, 0, X_GLXGetDrawableAttributes, false);
       return 0;
    }
@@ -269,6 +270,7 @@ __glXGetDrawableAttribute(Display * dpy, GLXDrawable drawable,
       if (pdraw == NULL || gc == &dummyContext || gc->currentDpy != dpy ||
          (gc->currentDrawable != drawable &&
          gc->currentReadable != drawable)) {
+         XNoOp(dpy);
          __glXSendError(dpy, GLXBadDrawable, drawable,
                         X_GLXGetDrawableAttributes, false);
          return 0;