[gcr] ui: prompt-dialog: rewrite keyboard grabbing to work with Gdk >= 3.20

[Daiki Ueno <dueno src gnome org>]

commit 879b2734a9af3d8658b7b760c609daaf5b5d4fec
Author: Dmitry Eremin-Solenikov <dbaryshkov gmail com>
Date:   Sun Jan 12 23:53:21 2020 +0300

    ui: prompt-dialog: rewrite keyboard grabbing to work with Gdk >= 3.20
    
    Gdk 3.20 has deprecated several functions related to GdkDevice,
    replacing them with GdkSeat. Upgrade grabbing code correspondingly.
    
    Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov gmail com>

 ui/gcr-prompt-dialog.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)
---
diff --git a/ui/gcr-prompt-dialog.c b/ui/gcr-prompt-dialog.c
index 246ccd4..1b6de93 100644
--- a/ui/gcr-prompt-dialog.c
+++ b/ui/gcr-prompt-dialog.c
@@ -107,7 +107,11 @@ struct _GcrPromptDialogPrivate {
        GtkEntryBuffer *password_buffer;
        GtkEntryBuffer *confirm_buffer;
        PromptMode mode;
+#if GTK_CHECK_VERSION (3,20,0)
+       GdkSeat *grabbed_seat;
+#else
        GdkDevice *grabbed_device;
+#endif
        gulong grab_broken_id;
        gboolean grab_disabled;
        gboolean was_closed;
@@ -394,6 +398,57 @@ on_grab_broken (GtkWidget *widget,
        return TRUE;
 }
 
+#if GTK_CHECK_VERSION (3,20,0)
+static gboolean
+grab_keyboard (GtkWidget *widget,
+               GdkEvent *event,
+               gpointer user_data)
+{
+       GcrPromptDialog *self = GCR_PROMPT_DIALOG (user_data);
+       GdkGrabStatus status;
+       GdkSeat *seat;
+       GdkDisplay *display;
+
+       if (self->pv->grabbed_seat || !GRAB_KEYBOARD)
+               return FALSE;
+
+       display = gtk_widget_get_display (widget);
+       seat = gdk_display_get_default_seat (display);
+       status = gdk_seat_grab (seat, gtk_widget_get_window (widget),
+                               GDK_SEAT_CAPABILITY_ALL,
+                               TRUE, NULL, event, NULL, NULL);
+       if (status == GDK_GRAB_SUCCESS) {
+               self->pv->grab_broken_id = g_signal_connect (widget, "grab-broken-event",
+                                                            G_CALLBACK (on_grab_broken), self);
+               gtk_grab_add (widget);
+               self->pv->grabbed_seat = seat;
+       } else {
+               g_message ("could not grab keyboard: %s", grab_status_message (status));
+       }
+
+       /* Always return false, so event is handled elsewhere */
+       return FALSE;
+}
+
+static gboolean
+ungrab_keyboard (GtkWidget *widget,
+                 GdkEvent *event,
+                 gpointer user_data)
+{
+       GcrPromptDialog *self = GCR_PROMPT_DIALOG (user_data);
+
+       if (self->pv->grabbed_seat) {
+               g_signal_handler_disconnect (widget, self->pv->grab_broken_id);
+               gdk_seat_ungrab (self->pv->grabbed_seat);
+               gtk_grab_remove (widget);
+               self->pv->grabbed_seat = NULL;
+               self->pv->grab_broken_id = 0;
+       }
+
+       /* Always return false, so event is handled elsewhere */
+       return FALSE;
+}
+#else
 static gboolean
 grab_keyboard (GtkWidget *widget,
                GdkEvent *event,
@@ -461,6 +516,7 @@ ungrab_keyboard (GtkWidget *widget,
        /* Always return false, so event is handled elsewhere */
        return FALSE;
 }
+#endif
 
 static gboolean
 window_state_changed (GtkWidget *win, GdkEventWindowState *event, gpointer data)
@@ -725,7 +781,11 @@ gcr_prompt_dialog_dispose (GObject *obj)
        gcr_prompt_close (GCR_PROMPT (self));
 
        ungrab_keyboard (GTK_WIDGET (self), NULL, self);
+#if GTK_CHECK_VERSION (3,20,0)
+       g_assert (self->pv->grabbed_seat == NULL);
+#else
        g_assert (self->pv->grabbed_device == NULL);
+#endif
 
        G_OBJECT_CLASS (gcr_prompt_dialog_parent_class)->dispose (obj);
 }