Try harder to handle accelerators involving virtual modifiers

This patch changes GDK to add all matching virtual modifiers in
the state field of the key event. The corresponding GTK+ change makes
use of a new GdkKeymap function to map virtual modifiers back to
real modifiers and detect conflicts while doing so.

This should fix bug 603190 and bug 427409.

3 files changed, 61 insertions, 3 deletions

diff --git a/gdk/gdk.symbols b/gdk/gdk.symbols
index c49568d907..12967c425f 100644
--- a/gdk/gdk.symbols
+++ b/gdk/gdk.symbols
@@ -852,6 +852,7 @@ gdk_keymap_have_bidi_layouts
 gdk_keymap_get_caps_lock_state
 gdk_keymap_lookup_key
 gdk_keymap_translate_keyboard_state
+gdk_keymap_map_virtual_modifiers
 gdk_keyval_convert_case
 gdk_keyval_from_name
 gdk_keyval_name G_GNUC_CONST
diff --git a/gdk/gdkkeys.h b/gdk/gdkkeys.h
index 63a226620b..6fe55f7bb2 100644
--- a/gdk/gdkkeys.h
+++ b/gdk/gdkkeys.h
@@ -108,6 +108,8 @@ gboolean       gdk_keymap_get_entries_for_keycode  (GdkKeymap           *keymap,
 PangoDirection gdk_keymap_get_direction            (GdkKeymap           *keymap);
 gboolean       gdk_keymap_have_bidi_layouts        (GdkKeymap           *keymap);
 gboolean       gdk_keymap_get_caps_lock_state      (GdkKeymap           *keymap);
+gboolean       gdk_keymap_map_virtual_modifiers    (GdkKeymap           *keymap,
+                                                    GdkModifierType     *state);
 
 /* Key values
  */
diff --git a/gdk/x11/gdkkeys-x11.c b/gdk/x11/gdkkeys-x11.c
index 8cb5b3bcf5..97727c644d 100644
--- a/gdk/x11/gdkkeys-x11.c
+++ b/gdk/x11/gdkkeys-x11.c
@@ -1672,11 +1672,11 @@ _gdk_keymap_add_virtual_modifiers (GdkKeymap       *keymap,
         {
 	  if (keymap_x11->modmap[i] & GDK_MOD1_MASK)
 	    *modifiers |= GDK_MOD1_MASK;
-	  else if (keymap_x11->modmap[i] & GDK_SUPER_MASK)
+	  if (keymap_x11->modmap[i] & GDK_SUPER_MASK)
 	    *modifiers |= GDK_SUPER_MASK;
-	  else if (keymap_x11->modmap[i] & GDK_HYPER_MASK)
+	  if (keymap_x11->modmap[i] & GDK_HYPER_MASK)
 	    *modifiers |= GDK_HYPER_MASK;
-	  else if (keymap_x11->modmap[i] & GDK_META_MASK)
+	  if (keymap_x11->modmap[i] & GDK_META_MASK)
 	    *modifiers |= GDK_META_MASK;
         }
     }
@@ -1717,6 +1717,61 @@ _gdk_keymap_key_is_modifier (GdkKeymap *keymap,
   return FALSE;
 }
 
+/*
+ * gdk_keymap_map_virtual_modifiers:
+ * @keymap: a #GdkKeymap
+ * @state: pointer to the modifier state to map
+ *
+ * Maps the virtual modifiers (i.e. Super, Hyper and Meta) which
+ * are set in @state to their non-virtual counterparts (i.e. Mod2,
+ * Mod3,...) and set the corresponding bits in @state.
+ *
+ * This function is useful when matching key events against
+ * accelerators.
+ *
+ * Returns: %TRUE if no virtual modifiers were mapped to the
+ *     same non-virtual modifier. Note that %FALSE is also returned
+ *     if a virtual modifier is mapped to a non-virtual modifier that
+ *     was already set in @state.
+ *
+ * Since: 2.20
+ */
+gboolean
+gdk_keymap_map_virtual_modifiers (GdkKeymap       *keymap,
+                                  GdkModifierType *state)
+{
+  GdkKeymapX11 *keymap_x11;
+  const guint vmods[] = {
+    GDK_SUPER_MASK, GDK_HYPER_MASK, GDK_META_MASK
+  };
+  int i, j;
+  gboolean retval;
+
+  keymap = GET_EFFECTIVE_KEYMAP (keymap);
+  keymap_x11 = GDK_KEYMAP_X11 (keymap);
+
+  retval = TRUE;
+
+  for (j = 0; j < 3; j++)
+    {
+      if (*state & vmods[j])
+        {
+          for (i = 3; i < 8; i++)
+            {
+              if (keymap_x11->modmap[i] & vmods[j])
+                {
+                  if (*state & (1 << i))
+                    retval = FALSE;
+                  else
+                    *state |= 1 << i;
+                }
+            }
+        }
+    }
+
+  return retval;
+}
+
 
 #define __GDK_KEYS_X11_C__
 #include "gdkaliasdef.c"