gdk: Add GdkSeat

https://bugzilla.gnome.org/show_bug.cgi?id=759309

6 files changed, 574 insertions, 0 deletions

diff --git a/gdk/Makefile.am b/gdk/Makefile.am
index dea10d15c0..f3ce6b9441 100644
--- a/gdk/Makefile.am
+++ b/gdk/Makefile.am
@@ -85,6 +85,7 @@ gdk_public_h_sources = 				\
 	gdkrectangle.h				\
 	gdkrgba.h				\
 	gdkscreen.h				\
+	gdkseat.h				\
 	gdkselection.h				\
 	gdktestutils.h				\
 	gdkthreads.h				\
@@ -112,6 +113,7 @@ gdk_private_headers = 				\
 	gdkframeclockprivate.h			\
 	gdkglcontextprivate.h			\
 	gdkscreenprivate.h			\
+	gdkseatprivate.h			\
 	gdkinternals.h				\
 	gdkintl.h				\
 	gdkkeysprivate.h			\
@@ -150,6 +152,7 @@ gdk_c_sources = 				\
 	gdkrectangle.c				\
 	gdkrgba.c				\
 	gdkscreen.c				\
+	gdkseat.c				\
 	gdkselection.c				\
 	gdkvisual.c				\
 	gdkwindow.c				\
diff --git a/gdk/gdk.h b/gdk/gdk.h
index 65246d7788..81ba7658af 100644
--- a/gdk/gdk.h
+++ b/gdk/gdk.h
@@ -51,6 +51,7 @@
 #include <gdk/gdkrectangle.h>
 #include <gdk/gdkrgba.h>
 #include <gdk/gdkscreen.h>
+#include <gdk/gdkseat.h>
 #include <gdk/gdkselection.h>
 #include <gdk/gdktestutils.h>
 #include <gdk/gdkthreads.h>
diff --git a/gdk/gdkseat.c b/gdk/gdkseat.c
new file mode 100644
index 0000000000..14cb99cf14
--- /dev/null
+++ b/gdk/gdkseat.c
@@ -0,0 +1,391 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2015 Red Hat
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Carlos Garnacho <carlosg@gnome.org>
+ */
+
+#include "config.h"
+
+#include <glib-object.h>
+#include "gdkdisplay.h"
+#include "gdkdevice.h"
+#include "gdkseatprivate.h"
+#include "gdkdeviceprivate.h"
+#include "gdkintl.h"
+
+/**
+ * SECTION:gdkseat
+ * @Short_description: Object representing an user seat
+ * @Title: GdkSeat
+ * @See_also: #GdkDisplay, #GdkDevice
+ *
+ * The #GdkSeat object represents a collection of input devices
+ * that belong to an user.
+ */
+
+typedef struct _GdkSeatPrivate GdkSeatPrivate;
+
+struct _GdkSeatPrivate
+{
+  GdkDisplay *display;
+};
+
+enum {
+  DEVICE_ADDED,
+  DEVICE_REMOVED,
+  N_SIGNALS
+};
+
+enum {
+  PROP_0,
+  PROP_DISPLAY,
+  N_PROPS
+};
+
+static guint signals[N_SIGNALS] = { 0 };
+static GParamSpec *props[N_PROPS] = { NULL };
+
+G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GdkSeat, gdk_seat, G_TYPE_OBJECT)
+
+static void
+gdk_seat_set_property (GObject      *object,
+                       guint         prop_id,
+                       const GValue *value,
+                       GParamSpec   *pspec)
+{
+  GdkSeatPrivate *priv = gdk_seat_get_instance_private (GDK_SEAT (object));
+
+  switch (prop_id)
+    {
+    case PROP_DISPLAY:
+      priv->display = g_value_get_object (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+gdk_seat_get_property (GObject    *object,
+                       guint       prop_id,
+                       GValue     *value,
+                       GParamSpec *pspec)
+{
+  GdkSeatPrivate *priv = gdk_seat_get_instance_private (GDK_SEAT (object));
+
+  switch (prop_id)
+    {
+    case PROP_DISPLAY:
+      g_value_set_object (value, priv->display);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+gdk_seat_class_init (GdkSeatClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->set_property = gdk_seat_set_property;
+  object_class->get_property = gdk_seat_get_property;
+
+  /**
+   * GdkSeat::device-added:
+   * @seat: the object on which the signal is emitted
+   * @device: the newly added #GdkDevice.
+   *
+   * The ::device-added signal is emitted either when a new input
+   * device is related to this seat.
+   *
+   * Since: 3.20
+   */
+  signals [DEVICE_ADDED] =
+    g_signal_new (P_("device-added"),
+                  G_TYPE_FROM_CLASS (klass),
+                  G_SIGNAL_RUN_LAST,
+                  G_STRUCT_OFFSET (GdkSeatClass, device_added),
+                  NULL, NULL,
+                  g_cclosure_marshal_VOID__OBJECT,
+                  G_TYPE_NONE, 1,
+                  GDK_TYPE_DEVICE);
+
+  /**
+   * GdkSeat::device-removed:
+   * @seat: the object on which the signal is emitted
+   * @device: the just removed #GdkDevice.
+   *
+   * The ::device-removed signal is emitted either when an
+   * input device is removed (e.g. unplugged).
+   *
+   * Since: 3.20
+   */
+  signals [DEVICE_REMOVED] =
+    g_signal_new (P_("device-removed"),
+                  G_TYPE_FROM_CLASS (klass),
+                  G_SIGNAL_RUN_LAST,
+                  G_STRUCT_OFFSET (GdkSeatClass, device_removed),
+                  NULL, NULL,
+                  g_cclosure_marshal_VOID__OBJECT,
+                  G_TYPE_NONE, 1,
+                  GDK_TYPE_DEVICE);
+
+  /**
+   * GdkSeat:display:
+   *
+   * #GdkDisplay of this seat.
+   *
+   * Since: 3.20
+   */
+  props[PROP_DISPLAY] =
+    g_param_spec_object ("display",
+                         P_("Display"),
+                         P_("Display"),
+                         GDK_TYPE_DISPLAY,
+                         G_PARAM_READWRITE |
+                         G_PARAM_CONSTRUCT_ONLY |
+                         G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_properties (object_class, N_PROPS, props);
+}
+
+static void
+gdk_seat_init (GdkSeat *seat)
+{
+}
+
+/**
+ * gdk_seat_get_capabilities:
+ * @seat: a #GdkSeat
+ *
+ * Returns the capabilities this #GdkSeat currently has.
+ *
+ * Returns: the seat capabilities
+ *
+ * Since: 3.20
+ **/
+GdkSeatCapabilities
+gdk_seat_get_capabilities (GdkSeat *seat)
+{
+  GdkSeatClass *seat_class;
+
+  g_return_val_if_fail (GDK_IS_SEAT (seat), GDK_SEAT_CAPABILITY_NONE);
+
+  seat_class = GDK_SEAT_GET_CLASS (seat);
+  return seat_class->get_capabilities (seat);
+}
+
+/**
+ * gdk_seat_grab:
+ * @seat: a #GdkSeat
+ * @window: the #GdkWindow which will own the grab
+ * @capabilities: capabilities that will be grabbed
+ * @owner_events: if %FALSE then all device events are reported with respect to
+ *                @window and are only reported if selected by @event_mask. If
+ *                %TRUE then pointer events for this application are reported
+ *                as normal, but pointer events outside this application are
+ *                reported with respect to @window and only if selected by
+ *                @event_mask. In either mode, unreported events are discarded.
+ * @cursor: (nullable): the cursor to display while the grab is active. If
+ *          this is %NULL then the normal cursors are used for
+ *          @window and its descendants, and the cursor for @window is used
+ *          elsewhere.
+ * @event: (nullable): the event that is triggering the grab, or %NULL if none
+ *         is available.
+ * @prepare_func: (nullable) (scope call): function to prepare the window to be
+ *                grabbed, it can be %NULL if @window is visible before this call.
+ * @prepare_func_data: (closure prepare_func): user data to pass to @prepare_func
+ *
+ * Grabs the seat so that all events corresponding to the given @capabilities
+ * are passed to this application until the seat is ungrabbed with gdk_seat_ungrab(),
+ * or the window becomes hidden. This overrides any previous grab on the
+ * seat by this client.
+ *
+ * As a rule of thumb, if a grab is desired over %GDK_SEAT_CAPABILITY_POINTER,
+ * all other "pointing" capabilities (eg. %GDK_SEAT_CAPABILITY_TOUCH) should
+ * be grabbed too, so the user is able to interact with all of those while
+ * the grab holds, you should thus use %GDK_SEAT_CAPABILITY_ALL_POINTING most
+ * commonly.
+ *
+ * Grabs are used for operations which need complete control over the
+ * events corresponding to the given capabilities. For example in GTK+ this
+ * is used for Drag and Drop operations, popup menus and such.
+ *
+ * Note that if the event mask of a #GdkWindow has selected both button press
+ * and button release events, or touch begin and touch end, then a press event
+ * will cause an automatic grab until the button is released, equivalent to a
+ * grab on the window with @owner_events set to %TRUE. This performed as most
+ * applications expect to receive presses and releases in pairs.
+ *
+ * If you set up anything at the time you take the grab that needs to be
+ * cleaned up when the grab ends, you should handle the #GdkEventGrabBroken
+ * events that are emitted when the grab ends unvoluntarily.
+ *
+ * Returns: %GDK_GRAB_SUCCESS if the grab was successful.
+ *
+ * Since: 3.20
+ **/
+GdkGrabStatus
+gdk_seat_grab (GdkSeat                *seat,
+               GdkWindow              *window,
+               GdkSeatCapabilities     capabilities,
+               gboolean                owner_events,
+               GdkCursor              *cursor,
+               const GdkEvent         *event,
+               GdkSeatGrabPrepareFunc  prepare_func,
+               gpointer                prepare_func_data)
+{
+  GdkSeatClass *seat_class;
+
+  g_return_val_if_fail (GDK_IS_SEAT (seat), GDK_GRAB_FAILED);
+  g_return_val_if_fail (GDK_IS_WINDOW (window), GDK_GRAB_FAILED);
+
+  capabilities &= GDK_SEAT_CAPABILITY_ALL;
+  g_return_val_if_fail (capabilities != GDK_SEAT_CAPABILITY_NONE, GDK_GRAB_FAILED);
+
+  seat_class = GDK_SEAT_GET_CLASS (seat);
+
+  return seat_class->grab (seat, window, capabilities, owner_events, cursor,
+                           event, prepare_func, prepare_func_data);
+}
+
+/**
+ * gdk_seat_ungrab:
+ * @seat: a #GdkSeat
+ *
+ * Releases a grab added through gdk_seat_grab().
+ *
+ * Since: 3.20
+ **/
+void
+gdk_seat_ungrab (GdkSeat *seat)
+{
+  GdkSeatClass *seat_class;
+
+  g_return_if_fail (GDK_IS_SEAT (seat));
+
+  seat_class = GDK_SEAT_GET_CLASS (seat);
+  return seat_class->ungrab (seat);
+}
+
+/**
+ * gdk_seat_get_slaves:
+ * @seat: a #GdkSeat
+ * @capabilities: capabilities to get devices for
+ *
+ * Returns the slave devices that match the given capabilities.
+ *
+ * Returns: (transfer container) (element-type GdkSeat): A list of #GdkDevices. The list
+ *          must be freed with g_list_free(), the elements are owned
+ *          by GDK and must not be freed.
+ *
+ * Since: 3.20
+ **/
+GList *
+gdk_seat_get_slaves (GdkSeat             *seat,
+                     GdkSeatCapabilities  capabilities)
+{
+  GdkSeatClass *seat_class;
+
+  g_return_val_if_fail (GDK_IS_SEAT (seat), NULL);
+
+  seat_class = GDK_SEAT_GET_CLASS (seat);
+  return seat_class->get_slaves (seat, capabilities);
+}
+
+/**
+ * gdk_seat_get_pointer:
+ * @seat: a #GdkSeat
+ *
+ * Returns the master device that routes pointer events.
+ *
+ * Returns: (transfer none) (nullable): a master #GdkDevice with pointer
+ *          capabilities. This object is owned by GTK+ and must not be
+ *          freed.
+ *
+ * Since: 3.20
+ **/
+GdkDevice *
+gdk_seat_get_pointer (GdkSeat *seat)
+{
+  GdkSeatClass *seat_class;
+
+  g_return_val_if_fail (GDK_IS_SEAT (seat), NULL);
+
+  seat_class = GDK_SEAT_GET_CLASS (seat);
+  return seat_class->get_master (seat, GDK_SEAT_CAPABILITY_POINTER);
+}
+
+/**
+ * gdk_seat_get_keyboard:
+ * @seat: a #GdkSeat
+ *
+ * Returns the master device that routes keyboard events.
+ *
+ * Returns: (transfer none) (nullable): a master #GdkDevice with keyboard
+ *          capabilities. This object is owned by GTK+ and must not be
+ *          freed.
+ *
+ * Since: 3.20
+ **/
+GdkDevice *
+gdk_seat_get_keyboard (GdkSeat *seat)
+{
+  GdkSeatClass *seat_class;
+
+  g_return_val_if_fail (GDK_IS_SEAT (seat), NULL);
+
+  seat_class = GDK_SEAT_GET_CLASS (seat);
+  return seat_class->get_master (seat, GDK_SEAT_CAPABILITY_KEYBOARD);
+}
+
+void
+gdk_seat_device_added (GdkSeat   *seat,
+                       GdkDevice *device)
+{
+  gdk_device_set_seat (device, seat);
+  g_signal_emit (seat, signals[DEVICE_ADDED], 0, device);
+}
+
+void
+gdk_seat_device_removed (GdkSeat   *seat,
+                         GdkDevice *device)
+{
+  gdk_device_set_seat (device, NULL);
+  g_signal_emit (seat, signals[DEVICE_REMOVED], 0, device);
+}
+
+/**
+ * gdk_seat_get_display:
+ * @seat: a #GdkSeat
+ *
+ * Returns the #GdkDisplay this seat belongs to.
+ *
+ * Returns: (transfer none): a #GdkDisplay. This memory is owned by GTK+ and
+ *          must not be freed.
+ **/
+GdkDisplay *
+gdk_seat_get_display (GdkSeat *seat)
+{
+  GdkSeatPrivate *priv = gdk_seat_get_instance_private (seat);
+
+  g_return_val_if_fail (GDK_IS_SEAT (seat), NULL);
+
+  return priv->display;
+}
diff --git a/gdk/gdkseat.h b/gdk/gdkseat.h
new file mode 100644
index 0000000000..e91e620d54
--- /dev/null
+++ b/gdk/gdkseat.h
@@ -0,0 +1,113 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2015 Red Hat
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Carlos Garnacho <carlosg@gnome.org>
+ */
+
+#ifndef __GDK_SEAT_H__
+#define __GDK_SEAT_H__
+
+#if !defined (__GDK_H_INSIDE__) && !defined (GDK_COMPILATION)
+#error "Only <gdk/gdk.h> can be included directly."
+#endif
+
+#include <glib-object.h>
+#include <gdk/gdkwindow.h>
+#include <gdk/gdkevents.h>
+#include <gdk/gdktypes.h>
+
+#define GDK_TYPE_SEAT  (gdk_seat_get_type ())
+#define GDK_SEAT(o)    (G_TYPE_CHECK_INSTANCE_CAST ((o), GDK_TYPE_SEAT, GdkSeat))
+#define GDK_IS_SEAT(o) (G_TYPE_CHECK_INSTANCE_TYPE ((o), GDK_TYPE_SEAT))
+
+/**
+ * GdkSeatCapabilities:
+ * @GDK_SEAT_CAPABILITY_NONE: No input capabilities
+ * @GDK_SEAT_CAPABILITY_POINTER: The seat has a pointer (e.g. mouse)
+ * @GDK_SEAT_CAPABILITY_TOUCH: The seat has touchscreen(s) attached
+ * @GDK_SEAT_CAPABILITY_TABLET_STYLUS: The seat has drawing tablet(s) attached
+ * @GDK_SEAT_CAPABILITY_KEYBOARD: The seat has keyboard(s) attached
+ * @GDK_SEAT_CAPABILITY_ALL_POINTING: The union of all pointing capabilities
+ * @GDK_SEAT_CAPABILITY_ALL: The union of all capabilities
+ *
+ * Flags describing the seat capabilities.
+ *
+ * Since: 3.20
+ */
+typedef enum {
+  GDK_SEAT_CAPABILITY_NONE          = 0,
+  GDK_SEAT_CAPABILITY_POINTER       = 1 << 0,
+  GDK_SEAT_CAPABILITY_TOUCH         = 1 << 1,
+  GDK_SEAT_CAPABILITY_TABLET_STYLUS = 1 << 2,
+  GDK_SEAT_CAPABILITY_KEYBOARD      = 1 << 3,
+  GDK_SEAT_CAPABILITY_ALL_POINTING  = (GDK_SEAT_CAPABILITY_POINTER | GDK_SEAT_CAPABILITY_TOUCH | GDK_SEAT_CAPABILITY_TABLET_STYLUS),
+  GDK_SEAT_CAPABILITY_ALL           = (GDK_SEAT_CAPABILITY_ALL_POINTING | GDK_SEAT_CAPABILITY_KEYBOARD)
+} GdkSeatCapabilities;
+
+/**
+ * GdkSeatGrabPrepareFunc:
+ * @seat: the #GdkSeat being grabbed
+ * @window: the #GdkWindow being grabbed
+ * @user_data: user data passed in gdk_seat_grab()
+ *
+ * Type of the callback used to set up @window so it can be
+ * grabbed. A typical action would be ensuring the window is
+ * visible, although there's room for other initialization
+ * actions.
+ *
+ * Since: 3.20
+ */
+typedef void (* GdkSeatGrabPrepareFunc) (GdkSeat   *seat,
+                                         GdkWindow *window,
+                                         gpointer   user_data);
+
+struct _GdkSeat
+{
+  GObject parent_instance;
+};
+
+GDK_AVAILABLE_IN_3_20
+GType          gdk_seat_get_type         (void) G_GNUC_CONST;
+
+GDK_AVAILABLE_IN_3_20
+GdkGrabStatus  gdk_seat_grab             (GdkSeat                *seat,
+                                          GdkWindow              *window,
+                                          GdkSeatCapabilities     capabilities,
+                                          gboolean                owner_events,
+                                          GdkCursor              *cursor,
+                                          const GdkEvent         *event,
+                                          GdkSeatGrabPrepareFunc  prepare_func,
+                                          gpointer                prepare_func_data);
+GDK_AVAILABLE_IN_3_20
+void           gdk_seat_ungrab           (GdkSeat                *seat);
+
+GDK_AVAILABLE_IN_3_20
+GdkDisplay *   gdk_seat_get_display      (GdkSeat             *seat);
+
+GDK_AVAILABLE_IN_3_20
+GdkSeatCapabilities
+               gdk_seat_get_capabilities (GdkSeat             *seat);
+
+GDK_AVAILABLE_IN_3_20
+GList *        gdk_seat_get_slaves       (GdkSeat             *seat,
+                                          GdkSeatCapabilities  capabilities);
+
+GDK_AVAILABLE_IN_3_20
+GdkDevice *    gdk_seat_get_pointer      (GdkSeat             *seat);
+GDK_AVAILABLE_IN_3_20
+GdkDevice *    gdk_seat_get_keyboard     (GdkSeat             *seat);
+
+#endif /* __GDK_SEAT_H__ */
diff --git a/gdk/gdkseatprivate.h b/gdk/gdkseatprivate.h
new file mode 100644
index 0000000000..f8d84c8c2d
--- /dev/null
+++ b/gdk/gdkseatprivate.h
@@ -0,0 +1,65 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 2015 Red Hat
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Carlos Garnacho <carlosg@gnome.org>
+ */
+
+#ifndef __GDK_SEAT_PRIVATE_H__
+#define __GDK_SEAT_PRIVATE_H__
+
+typedef struct _GdkSeatClass GdkSeatClass;
+
+#include "gdkseat.h"
+
+#define GDK_SEAT_CLASS(c)     (G_TYPE_CHECK_CLASS_CAST ((c), GDK_TYPE_SEAT, GdkSeatClass))
+#define GDK_IS_SEAT_CLASS(c)  (G_TYPE_CHECK_CLASS_TYPE ((c), GDK_TYPE_SEAT))
+#define GDK_SEAT_GET_CLASS(o) (G_TYPE_INSTANCE_GET_CLASS ((o), GDK_TYPE_SEAT, GdkSeatClass))
+
+struct _GdkSeatClass
+{
+  GObjectClass parent_class;
+
+  void (* device_added)   (GdkSeat   *seat,
+                           GdkDevice *device);
+  void (* device_removed) (GdkSeat   *seat,
+                           GdkDevice *device);
+  void (* device_changed) (GdkSeat   *seat,
+                           GdkDevice *device);
+
+  GdkSeatCapabilities (*get_capabilities) (GdkSeat *seat);
+
+  GdkGrabStatus (* grab)   (GdkSeat                *seat,
+                            GdkWindow              *window,
+                            GdkSeatCapabilities     capabilities,
+                            gboolean                owner_events,
+                            GdkCursor              *cursor,
+                            const GdkEvent         *event,
+                            GdkSeatGrabPrepareFunc  prepare_func,
+                            gpointer                prepare_func_data);
+  void          (* ungrab) (GdkSeat                *seat);
+
+  GdkDevice * (* get_master) (GdkSeat             *seat,
+                              GdkSeatCapabilities  capability);
+  GList *     (* get_slaves) (GdkSeat             *seat,
+                              GdkSeatCapabilities  capabilities);
+};
+
+void gdk_seat_device_added   (GdkSeat   *seat,
+                              GdkDevice *device);
+void gdk_seat_device_removed (GdkSeat   *seat,
+                              GdkDevice *device);
+
+#endif /* __GDK_SEAT_PRIVATE_H__ */
diff --git a/gdk/gdktypes.h b/gdk/gdktypes.h
index bcd499dddb..cee717ee6b 100644
--- a/gdk/gdktypes.h
+++ b/gdk/gdktypes.h
@@ -143,6 +143,7 @@ typedef struct _GdkScreen             GdkScreen;
 typedef struct _GdkWindow             GdkWindow;
 typedef struct _GdkKeymap             GdkKeymap;
 typedef struct _GdkAppLaunchContext   GdkAppLaunchContext;
+typedef struct _GdkSeat               GdkSeat;
 
 typedef struct _GdkGLContext          GdkGLContext;