From be06b40ebdd6cfbd23558ce210a8a7ad2b4c7a40 Mon Sep 17 00:00:00 2001
From: Po Lu <luangruo@yahoo.com>
Date: Sat, 12 Feb 2022 20:25:00 +0800
Subject: [PATCH] Fix entry and exit events with XI2 grabs on X toolkit menus

* src/xmenu.c (popup_get_selection): Only claim cookie if new
event will be generated.
(create_and_show_popup_menu): Ungrab XI2 device, then
immediately set core grab on the frame's edit widget window.

* src/xterm.c (handle_one_xevent): Use x_any_window_to_frame to
find exit event frame if a popup menu is active.
---
 src/xmenu.c | 53 +++++++++++++++++++++++++++++++++++++++++++----------
 src/xterm.c | 11 +++++++++++
 2 files changed, 54 insertions(+), 10 deletions(-)

diff --git a/src/xmenu.c b/src/xmenu.c
index eaec6efc26c..28fafa108da 100644
--- a/src/xmenu.c
+++ b/src/xmenu.c
@@ -299,16 +299,16 @@ popup_get_selection (XEvent *initial_event, struct x_display_info *dpyinfo,
 	       && event.xgeneric.display == dpyinfo->display
 	       && event.xgeneric.extension == dpyinfo->xi2_opcode)
 	{
-	  if (!event.xcookie.data
-	      && XGetEventData (dpyinfo->display, &event.xcookie))
-	    cookie_claimed_p = true;
-
 	  if (event.xcookie.data)
 	    {
 	      switch (event.xgeneric.evtype)
 		{
 		case XI_ButtonRelease:
 		  {
+		    if (!event.xcookie.data
+			&& XGetEventData (dpyinfo->display, &event.xcookie))
+		      cookie_claimed_p = true;
+
 		    xev = (XIDeviceEvent *) event.xcookie.data;
 		    device = xi_device_from_id (dpyinfo, xev->deviceid);
 
@@ -358,6 +358,10 @@ popup_get_selection (XEvent *initial_event, struct x_display_info *dpyinfo,
 		  {
 		    KeySym keysym;
 
+		    if (!event.xcookie.data
+			&& XGetEventData (dpyinfo->display, &event.xcookie))
+		      cookie_claimed_p = true;
+
 		    xev = (XIDeviceEvent *) event.xcookie.data;
 
 		    copy.xkey.type = KeyPress;
@@ -1578,26 +1582,55 @@ create_and_show_popup_menu (struct frame *f, widget_value *first_wv,
   XtSetArg (av[ac], (char *) XtNgeometry, 0); ac++;
   XtSetValues (menu, av, ac);
 
-#if defined HAVE_XINPUT2 && defined USE_X_TOOLKIT
+#if defined HAVE_XINPUT2
   struct x_display_info *dpyinfo = FRAME_DISPLAY_INFO (f);
-  /* Clear the XI2 grab so lwlib can set a core grab.  */
+  bool any_xi_grab_p = false;
+
+  /* Clear the XI2 grab, and if any XI2 grab was set, place a core
+     grab on the frame's edit widget.  */
+
+  if (dpyinfo->supports_xi2)
+    XGrabServer (dpyinfo->display);
 
   if (dpyinfo->num_devices)
     {
       for (int i = 0; i < dpyinfo->num_devices; ++i)
 	{
-#ifndef USE_MOTIF
 	  if (dpyinfo->devices[i].grab)
-#endif
-	    XIUngrabDevice (dpyinfo->display, dpyinfo->devices[i].device_id,
-			    CurrentTime);
+	    {
+	      any_xi_grab_p = true;
+	      dpyinfo->devices[i].grab = 0;
+
+	      XIUngrabDevice (dpyinfo->display,
+			      dpyinfo->devices[i].device_id,
+			      CurrentTime);
+	    }
 	}
     }
+
+  if (any_xi_grab_p)
+    XGrabPointer (dpyinfo->display,
+		  FRAME_X_WINDOW (f),
+		  False, (PointerMotionMask
+			  | PointerMotionHintMask
+			  | ButtonReleaseMask
+			  | ButtonPressMask),
+		  GrabModeSync, GrabModeAsync,
+		  None, None, CurrentTime);
+
+  if (dpyinfo->supports_xi2)
+    XUngrabServer (dpyinfo->display);
 #endif
 
   /* Display the menu.  */
   lw_popup_menu (menu, &dummy);
   popup_activated_flag = 1;
+
+#ifdef HAVE_XINPUT2
+  if (any_xi_grab_p)
+    XAllowEvents (dpyinfo->display, AsyncPointer, CurrentTime);
+#endif
+
   x_activate_timeout_atimer ();
 
   {
diff --git a/src/xterm.c b/src/xterm.c
index 22c14380767..20ea7468202 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -10877,6 +10877,17 @@ handle_one_xevent (struct x_display_info *dpyinfo,
 	    ev.window = leave->event;
 	    any = x_top_window_to_frame (dpyinfo, leave->event);
 
+	    /* This allows us to catch LeaveNotify events generated by
+	       popup menu grabs.  FIXME: this is right when there is a
+	       focus menu, but implicit focus tracking can get screwed
+	       up if we get this and no XI_Enter event later.   */
+
+#ifdef USE_X_TOOLKIT
+	    if (popup_activated ()
+		&& leave->mode == XINotifyPassiveUngrab)
+	      any = x_any_window_to_frame (dpyinfo, leave->event);
+#endif
+
 	    /* One problem behind the design of XInput 2 scrolling is
 	       that valuators are not unique to each window, but only
 	       the window that has grabbed the valuator's device or
-- 
2.39.5