[folks] ofono: Throw a useful error if prepare() fails for a missing D-Bus service

[Philip Withnall <pwithnall src gnome org>]

commit 5248f654d5f74b1565f485769cfc5108f2cacaa9
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Mon Nov 4 13:42:41 2013 +0000

    ofono: Throw a useful error if prepare() fails for a missing D-Bus service
    
    Previously the error was completely unhelpful.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=711403

 backends/ofono/ofono-backend.vala |   26 ++++++++++++++++++--------
 po/POTFILES.in                    |    1 +
 po/POTFILES.skip                  |    1 +
 3 files changed, 20 insertions(+), 8 deletions(-)
---
diff --git a/backends/ofono/ofono-backend.vala b/backends/ofono/ofono-backend.vala
index bd62c5f..1394e21 100644
--- a/backends/ofono/ofono-backend.vala
+++ b/backends/ofono/ofono-backend.vala
@@ -162,7 +162,7 @@ public class Folks.Backends.Ofono.Backend : Folks.Backend
   /**
    * { inheritDoc}
    */
-  public override async void prepare () throws GLib.Error
+  public override async void prepare () throws DBusError
     {
       Internal.profiling_start ("preparing Ofono.Backend");
 
@@ -176,13 +176,23 @@ public class Folks.Backends.Ofono.Backend : Folks.Backend
           this._prepare_pending = true;
 
           /* New modem devices can be caught in notifications */
-          Manager manager = yield Bus.get_proxy (BusType.SYSTEM,
-                                                       "org.ofono",
-                                                       "/");
-          manager.ModemAdded.connect (this._modem_added);
-          manager.ModemRemoved.connect (this._modem_removed);
-          
-          this._modems = manager.GetModems ();
+          Manager manager;
+
+          try
+            {
+              manager = yield Bus.get_proxy (BusType.SYSTEM, "org.ofono", "/");
+              manager.ModemAdded.connect (this._modem_added);
+              manager.ModemRemoved.connect (this._modem_removed);
+
+              this._modems = manager.GetModems ();
+            }
+          catch (GLib.Error e1)
+            {
+              throw new DBusError.SERVICE_UNKNOWN (
+                  _("No oFono object manager running, so the oFono " +
+                    "backend will be inactive. Either oFono isn’t installed " +
+                    "or the service can’t be started."));
+            }
 
           foreach (ModemProperties modem in this._modems)
             {
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 2cec85a..8d8e71a 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -6,6 +6,7 @@ backends/key-file/kf-backend-factory.vala
 backends/key-file/kf-persona-store.vala
 backends/key-file/kf-persona.vala
 backends/libsocialweb/lib/swf-persona-store.vala
+backends/ofono/ofono-backend.vala
 backends/telepathy/lib/tp-lowlevel.c
 backends/telepathy/lib/tpf-persona-store.vala
 backends/telepathy/lib/tpf-persona.vala
diff --git a/po/POTFILES.skip b/po/POTFILES.skip
index 9a79619..d7a74b0 100644
--- a/po/POTFILES.skip
+++ b/po/POTFILES.skip
@@ -5,6 +5,7 @@ backends/key-file/kf-backend-factory.c
 backends/key-file/kf-persona-store.c
 backends/key-file/kf-persona.c
 backends/libsocialweb/lib/swf-persona-store.c
+backends/ofono/ofono-backend.c
 backends/telepathy/lib/tpf-persona-store.c
 backends/telepathy/lib/tpf-persona.c
 backends/tracker/lib/trf-persona-store.c