From db9b9435cddb1201bc57c65f44f90208e7047582 Mon Sep 17 00:00:00 2001
From: Po Lu <luangruo@yahoo.com>
Date: Tue, 1 Mar 2022 14:44:02 +0800
Subject: [PATCH] Fix old X menu on builds with XI2

* oldXMenu/Activate.c (XMenuActivateSetTranslateFunction): New
function.
(XMenuActivate): Handle generic events.
* oldXMenu/XMenu.h: New prototypes.
(Translate_func): New type.
* src/xmenu.c (x_menu_wait_translate_generic_event): New
function.
(x_menu_show): Set translate function.
---
 oldXMenu/Activate.c | 13 ++++++++++
 oldXMenu/XMenu.h    |  6 +++++
 src/xmenu.c         | 61 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 80 insertions(+)

diff --git a/oldXMenu/Activate.c b/oldXMenu/Activate.c
index 646631df84b..447b7398ca2 100644
--- a/oldXMenu/Activate.c
+++ b/oldXMenu/Activate.c
@@ -121,6 +121,7 @@ int x_menu_grab_keyboard = 1;
 
 static Wait_func wait_func;
 static void* wait_data;
+static Translate_func translate_func = NULL;
 
 void
 XMenuActivateSetWaitFunction (Wait_func func, void *data)
@@ -129,6 +130,12 @@ XMenuActivateSetWaitFunction (Wait_func func, void *data)
   wait_data = data;
 }
 
+void
+XMenuActivateSetTranslateFunction (Translate_func func)
+{
+  translate_func = func;
+}
+
 int
 XMenuActivate(
     register Display *display,		/* Display to put menu on. */
@@ -515,6 +522,12 @@ XMenuActivate(
 		    feq = feq_tmp;
 		}
 		else if (_XMEventHandler) (*_XMEventHandler)(&event);
+		break;
+#ifdef HAVE_XINPUT2
+        case GenericEvent:
+	    if (translate_func)
+	      translate_func (&event);
+#endif
 	}
 	/*
 	 * If a selection has been made, break out of the event loop.
diff --git a/oldXMenu/XMenu.h b/oldXMenu/XMenu.h
index 50ea6834090..2eee18a3844 100644
--- a/oldXMenu/XMenu.h
+++ b/oldXMenu/XMenu.h
@@ -255,6 +255,11 @@ typedef struct _xmenu {
 
 typedef void (*Wait_func)(void*);
 
+/* Function for translating GenericEvents.  It is should call
+   XPutBackEvent on an equivalent artificial core event on any
+   function it wants to translate.  */
+typedef void (*Translate_func)(XEvent *);
+
 /*
  * XMenu library routine declarations.
  */
@@ -274,6 +279,7 @@ void XMenuEventHandler(int (*handler) (XEvent *));
 int XMenuLocate(Display *display, XMenu *menu, int p_num, int s_num, int x_pos, int y_pos, int *ul_x, int *ul_y, int *width, int *height);
 void XMenuSetFreeze(XMenu *menu, int freeze);
 void XMenuActivateSetWaitFunction(Wait_func func, void *data);
+void XMenuActivateSetTranslateFunction(Translate_func func);
 int XMenuActivate(Display *display, XMenu *menu, int *p_num, int *s_num, int x_pos, int y_pos, unsigned int event_mask, char **data, void (*help_callback) (char const *, int, int));
 char *XMenuPost(Display *display, XMenu *menu, int *p_num, int *s_num, int x_pos, int y_pos, int event_mask);
 int XMenuDeletePane(Display *display, XMenu *menu, int p_num);
diff --git a/src/xmenu.c b/src/xmenu.c
index e483c8f73b0..fb80221e15b 100644
--- a/src/xmenu.c
+++ b/src/xmenu.c
@@ -222,6 +222,64 @@ x_menu_wait_for_event (void *data)
 #endif
     }
 }
+
+#if !defined USE_GTK && !defined USE_X_TOOLKIT && defined HAVE_XINPUT2
+static void
+x_menu_translate_generic_event (XEvent *event)
+{
+  struct x_display_info *dpyinfo;
+  XEvent copy;
+  XIDeviceEvent *xev;
+
+  dpyinfo = x_display_info_for_display (event->xgeneric.display);
+
+  if (event->xgeneric.extension == dpyinfo->xi2_opcode)
+    {
+      eassert (!event->xcookie.data);
+
+      if (XGetEventData (dpyinfo->display, &event->xcookie))
+	{
+	  switch (event->xcookie.evtype)
+	    {
+	    case XI_ButtonPress:
+	    case XI_ButtonRelease:
+	      xev = (XIDeviceEvent *) event->xcookie.data;
+	      copy.xbutton.type = (event->xcookie.evtype == XI_ButtonPress
+				   ? ButtonPress : ButtonRelease);
+	      copy.xbutton.serial = xev->serial;
+	      copy.xbutton.send_event = xev->send_event;
+	      copy.xbutton.display = dpyinfo->display;
+	      copy.xbutton.window = xev->event;
+	      copy.xbutton.root = xev->root;
+	      copy.xbutton.subwindow = xev->child;
+	      copy.xbutton.time = xev->time;
+	      copy.xbutton.x = lrint (xev->event_x);
+	      copy.xbutton.y = lrint (xev->event_y);
+	      copy.xbutton.x_root = lrint (xev->root_x);
+	      copy.xbutton.y_root = lrint (xev->root_y);
+	      copy.xbutton.state = xev->mods.effective;
+	      copy.xbutton.button = xev->detail;
+	      copy.xbutton.same_screen = True;
+
+	      if (xev->buttons.mask_len)
+		{
+		  if (XIMaskIsSet (xev->buttons.mask, 1))
+		    copy.xbutton.state |= Button1Mask;
+		  if (XIMaskIsSet (xev->buttons.mask, 2))
+		    copy.xbutton.state |= Button2Mask;
+		  if (XIMaskIsSet (xev->buttons.mask, 3))
+		    copy.xbutton.state |= Button3Mask;
+		}
+
+	      XPutBackEvent (dpyinfo->display, &copy);
+
+	      break;
+	    }
+	  XFreeEventData (dpyinfo->display, &event->xcookie);
+	}
+    }
+}
+#endif
 #endif /* ! MSDOS */
 
 
@@ -2568,6 +2626,9 @@ x_menu_show (struct frame *f, int x, int y, int menuflags,
 
 #ifndef MSDOS
   XMenuActivateSetWaitFunction (x_menu_wait_for_event, FRAME_X_DISPLAY (f));
+#ifdef HAVE_XINPUT2
+  XMenuActivateSetTranslateFunction (x_menu_translate_generic_event);
+#endif
 #endif
 
   record_unwind_protect_ptr (pop_down_menu,
-- 
2.39.5