From: Po Lu <luangruo@yahoo.com>
Date: Fri, 22 Apr 2022 11:43:42 +0000 (+0800)
Subject: Don't transfer window attributes trying to find the XM drag window
X-Git-Tag: emacs-29.0.90~1931^2~364
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=05705454d5c616cb54294ae3bbb2d40ab72fc8ed;p=emacs.git

Don't transfer window attributes trying to find the XM drag window

* src/xterm.c (xm_get_drag_window): Select for impossible event
mask instead of asking for the window attributes.
---

diff --git a/src/xterm.c b/src/xterm.c
index adfe3059d1d..7e8d226fb26 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -1385,7 +1385,6 @@ xm_get_drag_window (struct x_display_info *dpyinfo)
   unsigned char *tmp_data = NULL;
   Window drag_window;
   XSetWindowAttributes attrs;
-  XWindowAttributes wattrs;
   Display *temp_display;
   void *old_handler;
 
@@ -1403,8 +1402,10 @@ xm_get_drag_window (struct x_display_info *dpyinfo)
 	{
 	  drag_window = *(Window *) tmp_data;
 	  x_catch_errors (dpyinfo->display);
-	  XGetWindowAttributes (dpyinfo->display,
-				drag_window, &wattrs);
+	  /* We use ButtonPressMask since it's one of the events an
+	     input-only window can never get.  */
+	  XSelectInput (dpyinfo->display, drag_window,
+			ButtonPressMask);
 	  rc = !x_had_errors_p (dpyinfo->display);
 	  x_uncatch_errors_after_check ();
 
@@ -1474,8 +1475,10 @@ xm_get_drag_window (struct x_display_info *dpyinfo)
 	 current display, and the XOpenDisplay above didn't
 	 accidentally connect to some other display.  */
       x_catch_errors (dpyinfo->display);
-      XGetWindowAttributes (dpyinfo->display,
-			    drag_window, &wattrs);
+      /* We use ButtonPressMask since it's one of the events an
+	 input-only window can never get.  */
+      XSelectInput (dpyinfo->display, drag_window,
+		    ButtonPressMask);
       rc = !x_had_errors_p (dpyinfo->display);
       x_uncatch_errors_after_check ();
       unblock_input ();