[mutter] backends: Pass seat ID to evdev ClutterDeviceManager

[Carlos Garnacho <carlosg src gnome org>]

commit 9c79a1631dccc70db529ef57e6a4fd97cf25b043
Author: Carlos Garnacho <carlosg gnome org>
Date:   Thu Feb 2 19:01:25 2017 +0100

    backends: Pass seat ID to evdev ClutterDeviceManager
    
    Clutter assumed seat0 which is most usually, but not always correct.
    Add an evdev-backend specific function to allow passing the seat
    that will be used for ClutterDeviceManager construction, which we
    already obtain in MetaLauncher.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=778092

 .../clutter/evdev/clutter-device-manager-evdev.c   |   19 ++++++++++++++++++-
 clutter/clutter/evdev/clutter-evdev.h              |    3 +++
 src/backends/native/meta-launcher.c                |    2 ++
 3 files changed, 23 insertions(+), 1 deletions(-)
---
diff --git a/clutter/clutter/evdev/clutter-device-manager-evdev.c 
b/clutter/clutter/evdev/clutter-device-manager-evdev.c
index ab1b21a..2a3c768 100644
--- a/clutter/clutter/evdev/clutter-device-manager-evdev.c
+++ b/clutter/clutter/evdev/clutter-device-manager-evdev.c
@@ -124,6 +124,7 @@ G_DEFINE_TYPE_WITH_CODE (ClutterDeviceManagerEvdev,
 static ClutterOpenDeviceCallback  device_open_callback;
 static ClutterCloseDeviceCallback device_close_callback;
 static gpointer                   device_callback_data;
+static gchar *                    evdev_seat_id;
 
 #ifdef CLUTTER_ENABLE_DEBUG
 static const char *device_type_str[] = {
@@ -2045,7 +2046,8 @@ clutter_device_manager_evdev_constructed (GObject *gobject)
       return;
     }
 
-  if (libinput_udev_assign_seat (priv->libinput, "seat0") == -1)
+  if (libinput_udev_assign_seat (priv->libinput,
+                                 evdev_seat_id ? evdev_seat_id : "seat0") == -1)
     {
       g_critical ("Failed to assign a seat to the libinput object.");
       libinput_unref (priv->libinput);
@@ -2794,3 +2796,18 @@ clutter_evdev_warp_pointer (ClutterInputDevice   *pointer_device,
 {
   notify_absolute_motion (pointer_device, ms2us(time_), x, y, NULL);
 }
+
+/**
+ * clutter_evdev_set_seat_id:
+ * @seat_id: The seat ID
+ *
+ * Sets the seat to assign to the libinput context.
+ *
+ * For reliable effects, this function must be called before clutter_init().
+ */
+void
+clutter_evdev_set_seat_id (const gchar *seat_id)
+{
+  g_free (evdev_seat_id);
+  evdev_seat_id = g_strdup (seat_id);
+}
diff --git a/clutter/clutter/evdev/clutter-evdev.h b/clutter/clutter/evdev/clutter-evdev.h
index 8e8f8d9..e17ec12 100644
--- a/clutter/clutter/evdev/clutter-evdev.h
+++ b/clutter/clutter/evdev/clutter-evdev.h
@@ -57,6 +57,9 @@ void  clutter_evdev_set_device_callbacks (ClutterOpenDeviceCallback  open_callba
                                           ClutterCloseDeviceCallback close_callback,
                                           gpointer                   user_data);
 
+CLUTTER_AVAILABLE_IN_ALL
+void  clutter_evdev_set_seat_id (const gchar *seat_id);
+
 CLUTTER_AVAILABLE_IN_1_10
 void  clutter_evdev_release_devices (void);
 CLUTTER_AVAILABLE_IN_1_10
diff --git a/src/backends/native/meta-launcher.c b/src/backends/native/meta-launcher.c
index abba17e..75d07ce 100644
--- a/src/backends/native/meta-launcher.c
+++ b/src/backends/native/meta-launcher.c
@@ -545,6 +545,8 @@ meta_launcher_new (GError **error)
   self->kms_fd = kms_fd;
   self->kms_file_path = kms_file_path;
 
+  clutter_evdev_set_seat_id (seat_id);
+
   clutter_evdev_set_device_callbacks (on_evdev_device_open,
                                       on_evdev_device_close,
                                       self);