Work around gtk_im_context_filter_keypress() issue with super key

* src/pgtkterm.c (x_find_modifier_meanings): Convert virtual super
to non-virtual one.
(pgtk_gtk_to_emacs_modifiers): Use non-virtual one.
(pgtk_emacs_to_gtk_modifiers): Use non-virtual one.
(key_press_event): Don't call pgtk_im_context_filter_keypress while
super is pressed.
* src/pgtkterm.h (struct pgtk_display_info): New member.

2 files changed, 32 insertions, 5 deletions

diff --git a/src/pgtkterm.c b/src/pgtkterm.c
index d7bbfe15117..ab61283e062 100644
--- a/src/pgtkterm.c
+++ b/src/pgtkterm.c
@@ -5424,6 +5424,25 @@ x_find_modifier_meanings (struct pgtk_display_info *dpyinfo)
       dpyinfo->meta_mod_mask = GDK_MOD1_MASK;
       dpyinfo->alt_mod_mask = 0;
     }
+
+  state = GDK_SUPER_MASK;
+  r = gdk_keymap_map_virtual_modifiers (keymap, &state);
+  if (r)
+    {
+      /* Super key exists. */
+      if (state == GDK_SUPER_MASK)
+        {
+          dpyinfo->super_mod_mask = GDK_MOD4_MASK;      /* maybe this is super. */
+        }
+      else
+        {
+          dpyinfo->super_mod_mask = state & ~GDK_SUPER_MASK;
+        }
+    }
+  else
+    {
+      dpyinfo->super_mod_mask = GDK_MOD4_MASK;
+    }
 }
 
 static void
@@ -5478,7 +5497,7 @@ pgtk_gtk_to_emacs_modifiers (struct pgtk_display_info *dpyinfo, int state)
     mod |= mod_meta;
   if (state & dpyinfo->alt_mod_mask)
     mod |= mod_alt;
-  if (state & GDK_SUPER_MASK)
+  if (state & dpyinfo->super_mod_mask)
     mod |= mod_super;
   if (state & GDK_HYPER_MASK)
     mod |= mod_hyper;
@@ -5502,7 +5521,7 @@ pgtk_emacs_to_gtk_modifiers (struct pgtk_display_info *dpyinfo, int state)
   if (state & mod_alt)
     mask |= dpyinfo->alt_mod_mask;
   if (state & mod_super)
-    mask |= GDK_SUPER_MASK;
+    mask |= dpyinfo->super_mod_mask;
   if (state & mod_hyper)
     mask |= GDK_HYPER_MASK;
   if (state & shift_modifier)
@@ -5594,8 +5613,16 @@ key_press_event (GtkWidget * widget, GdkEvent * event, gpointer * user_data)
 
   if (f != 0)
     {
-      if (pgtk_im_filter_keypress (f, &event->key))
-        return TRUE;
+      /* While super is pressed, gtk_im_context_filter_keypress() always process the
+       * key events ignoring super.
+       * As a work around, don't call it while super is pressed...
+       */
+      struct pgtk_display_info *dpyinfo = FRAME_DISPLAY_INFO (f);
+      if (!(event->key.state & dpyinfo->super_mod_mask))
+        {
+          if (pgtk_im_filter_keypress (f, &event->key))
+            return TRUE;
+        }
     }
 
   if (f != 0)
diff --git a/src/pgtkterm.h b/src/pgtkterm.h
index 641509bb4e6..a777885518e 100644
--- a/src/pgtkterm.h
+++ b/src/pgtkterm.h
@@ -235,7 +235,7 @@ struct pgtk_display_info
   struct frame *last_mouse_glyph_frame;
 
   /* Modifier masks in gdk */
-  int meta_mod_mask, alt_mod_mask;
+  int meta_mod_mask, alt_mod_mask, super_mod_mask;
 
   /* The last click event. */
   GdkEvent *last_click_event;