+ uint32_t fbconfigID = 0;
+ uint32_t visualID = 0;
+ uint32_t screen = 0;
+ Bool got_screen = False;
+
+ /* The GLX_EXT_import_context spec says:
+ *
+ * "If <contextID> does not refer to a valid context, then a BadContext
+ * error is generated; if <contextID> refers to direct rendering
+ * context then no error is generated but glXImportContextEXT returns
+ * NULL."
+ *
+ * If contextID is None, generate BadContext on the client-side. Other
+ * sorts of invalid contexts will be detected by the server in the
+ * __glXIsDirect call.
+ */
+ if (contextID == None) {
+ __glXSendError(dpy, GLXBadContext, contextID, X_GLXIsDirect, false);
+ return NULL;
+ }