[gnome-boxes] Allow Machine::connect_display to report errors

[Christophe Fergeau <teuf src gnome org>]

commit 8745a86a7f3724bcce797647ddfb31d20f3ad4b4
Author: Christophe Fergeau <cfergeau redhat com>
Date:   Mon Sep 17 13:51:48 2012 +0200

    Allow Machine::connect_display to report errors
    
    If an error occurs while we connect to a remote display, we
    currently have no way of reporting this to the user. When
    this happens, Boxes is stuck on showing a zoomed in box snapshot
    in the middle of the screen, and nothing else happens.
    This commit allows Machine::connect_display to throw exceptions, and
    catches them to report errors. However, this is just preparatory work
    as the various Machine::connect_display needs to be modified to actually
    report the errors they encounter.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=684224

 src/app.vala             |    9 ++++++++-
 src/libvirt-machine.vala |    2 +-
 src/machine.vala         |    2 +-
 src/remote-machine.vala  |    2 +-
 4 files changed, 11 insertions(+), 4 deletions(-)
---
diff --git a/src/app.vala b/src/app.vala
index 946ee37..776af62 100644
--- a/src/app.vala
+++ b/src/app.vala
@@ -686,7 +686,14 @@ private class Boxes.App: Boxes.UI {
                 status_id = machine.notify["status"].connect ( () => {
                     topbar.set_status (machine.status);
                 });
-                machine.connect_display.begin ();
+                machine.connect_display.begin ( (obj, res) => {
+                    try {
+                        machine.connect_display.end (res);
+                    } catch (GLib.Error e) {
+                        ui_state = UIState.COLLECTION;
+                        warning ("connect display failed: %s", e.message);
+                    }
+                });
                 ui_state = UIState.CREDS;
             } else
                 warning ("unknown item, fix your code");
diff --git a/src/libvirt-machine.vala b/src/libvirt-machine.vala
index f91f2e8..20cbb0a 100644
--- a/src/libvirt-machine.vala
+++ b/src/libvirt-machine.vala
@@ -25,7 +25,7 @@ private class Boxes.LibvirtMachine: Boxes.Machine {
         _reconnect_display = true;
     }
 
-    public override async void connect_display () {
+    public override async void connect_display () throws GLib.Error {
         if (_connect_display)
             return;
 
diff --git a/src/machine.vala b/src/machine.vala
index ebc5739..4a7723b 100644
--- a/src/machine.vala
+++ b/src/machine.vala
@@ -212,7 +212,7 @@ private abstract class Boxes.Machine: Boxes.CollectionItem, Boxes.IPropertiesPro
 
     public abstract List<Boxes.Property> get_properties (Boxes.PropertiesPage page);
 
-    public abstract async void connect_display ();
+    public abstract async void connect_display () throws GLib.Error;
 
     public virtual void disconnect_display () {
         if (display == null)
diff --git a/src/remote-machine.vala b/src/remote-machine.vala
index 6369a20..333c83f 100644
--- a/src/remote-machine.vala
+++ b/src/remote-machine.vala
@@ -15,7 +15,7 @@ private class Boxes.RemoteMachine: Boxes.Machine, Boxes.IPropertiesProvider {
         load_screenshot ();
     }
 
-    public override async void connect_display () {
+    public override async void connect_display () throws GLib.Error {
         if (display != null)
             return;