[mutter] clutter/evdev: Implement ClutterVirtualInputDevice::notify_keyval

[Carlos Garnacho <carlosg src gnome org>]

commit b53b94e6f2400a705f057ba1132ab721658773ee
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Jul 20 18:03:44 2016 +0200

    clutter/evdev: Implement ClutterVirtualInputDevice::notify_keyval
    
    This is somewhat gross at the moment, because we're after all mimicking
    real keyboard events, we can only lookup keycodes that are available
    in the current map, and the control of levels is rather limited.
    
    Eventually, we want to implement the text_input protocol, handle these
    events separately to MetaWaylandKeyboard, so event->key.keyval is
    is guaranteed to be the final result. Until then, this is the farthest
    we can get.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=765009

 .../evdev/clutter-virtual-input-device-evdev.c     |  138 ++++++++++++++++++++
 1 files changed, 138 insertions(+), 0 deletions(-)
---
diff --git a/clutter/clutter/evdev/clutter-virtual-input-device-evdev.c 
b/clutter/clutter/evdev/clutter-virtual-input-device-evdev.c
index 5ce84d1..3d8c204 100644
--- a/clutter/clutter/evdev/clutter-virtual-input-device-evdev.c
+++ b/clutter/clutter/evdev/clutter-virtual-input-device-evdev.c
@@ -245,6 +245,143 @@ clutter_virtual_input_device_evdev_notify_key (ClutterVirtualInputDevice *virtua
                                  TRUE);
 }
 
+static gboolean
+pick_keycode_for_keyval_in_current_group (ClutterVirtualInputDevice *virtual_device,
+                                          guint                      keyval,
+                                          guint                     *keycode_out,
+                                          guint                     *level_out)
+{
+  ClutterVirtualInputDeviceEvdev *virtual_evdev =
+    CLUTTER_VIRTUAL_INPUT_DEVICE_EVDEV (virtual_device);
+  ClutterDeviceManager *manager;
+  struct xkb_keymap *xkb_keymap;
+  struct xkb_state  *state;
+  guint keycode, layout;
+  xkb_keycode_t min_keycode, max_keycode;
+
+  manager = clutter_virtual_input_device_get_manager (virtual_device);
+  xkb_keymap = _clutter_device_manager_evdev_get_keymap (CLUTTER_DEVICE_MANAGER_EVDEV (manager));
+  state = virtual_evdev->seat->xkb;
+
+  layout = xkb_state_serialize_layout (state, XKB_STATE_LAYOUT_EFFECTIVE);
+  min_keycode = xkb_keymap_min_keycode (xkb_keymap);
+  max_keycode = xkb_keymap_max_keycode (xkb_keymap);
+  for (keycode = min_keycode; keycode < max_keycode; keycode++)
+    {
+      gint num_levels, level;
+      num_levels = xkb_keymap_num_levels_for_key (xkb_keymap, keycode, layout);
+      for (level = 0; level < num_levels; level++)
+        {
+          const xkb_keysym_t *syms;
+          gint num_syms, sym;
+          num_syms = xkb_keymap_key_get_syms_by_level (xkb_keymap, keycode, layout, level, &syms);
+          for (sym = 0; sym < num_syms; sym++)
+            {
+              if (syms[sym] == keyval)
+                {
+                  *keycode_out = keycode;
+                  if (level_out)
+                    *level_out = level;
+                  return TRUE;
+                }
+            }
+        }
+    }
+
+  return FALSE;
+}
+
+static void
+apply_level_modifiers (ClutterVirtualInputDevice *virtual_device,
+                       uint64_t                   time_us,
+                       uint32_t                   level,
+                       uint32_t                   key_state)
+{
+  ClutterVirtualInputDeviceEvdev *virtual_evdev =
+    CLUTTER_VIRTUAL_INPUT_DEVICE_EVDEV (virtual_device);
+  guint keysym, keycode, evcode;
+
+  if (level == 0)
+    return;
+
+  if (level == 1)
+    {
+      keysym = XKB_KEY_Shift_L;
+    }
+  else if (level == 2)
+    {
+      keysym = XKB_KEY_ISO_Level3_Shift;
+    }
+  else
+    {
+      g_warning ("Unhandled level: %d\n", level);
+      return;
+    }
+
+  if (!pick_keycode_for_keyval_in_current_group (virtual_device, keysym,
+                                                 &keycode, NULL))
+    return;
+
+  clutter_input_device_keycode_to_evdev (virtual_evdev->device,
+                                         keycode, &evcode);
+  clutter_seat_evdev_notify_key (virtual_evdev->seat,
+                                 virtual_evdev->device,
+                                 time_us,
+                                 evcode,
+                                 key_state,
+                                 TRUE);
+}
+
+static void
+clutter_virtual_input_device_evdev_notify_keyval (ClutterVirtualInputDevice *virtual_device,
+                                                  uint64_t                   time_us,
+                                                  uint32_t                   keyval,
+                                                  ClutterKeyState            key_state)
+{
+  ClutterVirtualInputDeviceEvdev *virtual_evdev =
+    CLUTTER_VIRTUAL_INPUT_DEVICE_EVDEV (virtual_device);
+  int key_count;
+  guint keycode = 0, level = 0, evcode = 0;
+
+  if (!pick_keycode_for_keyval_in_current_group (virtual_device,
+                                                 keyval, &keycode, &level))
+    {
+      g_warning ("No keycode found for keyval %x in current group", keyval);
+      return;
+    }
+
+  clutter_input_device_keycode_to_evdev (virtual_evdev->device,
+                                         keycode, &evcode);
+
+  if (get_button_type (evcode) != EVDEV_BUTTON_TYPE_KEY)
+    {
+      g_warning ("Unknown/invalid virtual device key 0x%x pressed\n", evcode);
+      return;
+    }
+
+  key_count = update_button_count (virtual_evdev, evcode, key_state);
+  if (key_count < 0 || key_count > 1)
+    {
+      g_warning ("Received multiple virtual 0x%x key %s (ignoring)", keycode,
+                key_state == CLUTTER_KEY_STATE_PRESSED ? "presses" : "releases");
+      update_button_count (virtual_evdev, evcode, 1 - key_state);
+      return;
+    }
+
+  if (key_state)
+    apply_level_modifiers (virtual_device, time_us, level, key_state);
+
+  clutter_seat_evdev_notify_key (virtual_evdev->seat,
+                                 virtual_evdev->device,
+                                 time_us,
+                                 evcode,
+                                 key_state,
+                                 TRUE);
+
+  if (!key_state)
+    apply_level_modifiers (virtual_device, time_us, level, key_state);
+}
+
 static void
 clutter_virtual_input_device_evdev_get_property (GObject    *object,
                                                  guint       prop_id,
@@ -347,6 +484,7 @@ clutter_virtual_input_device_evdev_class_init (ClutterVirtualInputDeviceEvdevCla
   virtual_input_device_class->notify_absolute_motion = 
clutter_virtual_input_device_evdev_notify_absolute_motion;
   virtual_input_device_class->notify_button = clutter_virtual_input_device_evdev_notify_button;
   virtual_input_device_class->notify_key = clutter_virtual_input_device_evdev_notify_key;
+  virtual_input_device_class->notify_keyval = clutter_virtual_input_device_evdev_notify_keyval;
 
   obj_props[PROP_SEAT] = g_param_spec_pointer ("seat",
                                                P_("ClutterSeatEvdev"),