[evolution-data-server] ECalBackend: Add a "shutdown" signal.

[Matthew Barnes <mbarnes src gnome org>]

commit 2bf185b72c4e4252ea566e0bd9eaa851e6e13531
Author: Matthew Barnes <mbarnes redhat com>
Date:   Thu Aug 15 17:03:36 2013 -0400

    ECalBackend: Add a "shutdown" signal.
    
    The "shutdown" signal is emitted when the last client app destroys its
    EClient proxy object for a backend.  This signals the backend to begin
    final cleanup tasks such as synchronizing data to permanent storage.
    
    This increases the size of ECalBackendClass, and therefore requires a
    libedata-cal soname bump.

 calendar/libedata-cal/e-cal-backend.c      |   33 ++++++++++++++++++++++++++++
 calendar/libedata-cal/e-cal-backend.h      |    1 +
 calendar/libedata-cal/e-data-cal-factory.c |   27 ++++++++++++++++++++++
 configure.ac                               |    2 +-
 4 files changed, 62 insertions(+), 1 deletions(-)
---
diff --git a/calendar/libedata-cal/e-cal-backend.c b/calendar/libedata-cal/e-cal-backend.c
index 0446087..47a38ce 100644
--- a/calendar/libedata-cal/e-cal-backend.c
+++ b/calendar/libedata-cal/e-cal-backend.c
@@ -106,6 +106,7 @@ enum {
 
 enum {
        CLOSED,
+       SHUTDOWN,
        LAST_SIGNAL
 };
 
@@ -592,6 +593,19 @@ cal_backend_authenticate_sync (EBackend *backend,
 }
 
 static void
+cal_backend_shutdown (ECalBackend *backend)
+{
+       ESource *source;
+
+       source = e_backend_get_source (E_BACKEND (backend));
+
+       g_print (
+               "The %s instance for \"%s\" is shutting down.\n",
+               G_OBJECT_TYPE_NAME (backend),
+               e_source_get_display_name (source));
+}
+
+static void
 cal_backend_add_cached_timezone (ETimezoneCache *cache,
                                  icaltimezone *zone)
 {
@@ -767,6 +781,7 @@ e_cal_backend_class_init (ECalBackendClass *class)
        backend_class->authenticate_sync = cal_backend_authenticate_sync;
 
        class->get_backend_property = cal_backend_get_backend_property;
+       class->shutdown = cal_backend_shutdown;
 
        g_object_class_install_property (
                object_class,
@@ -834,6 +849,24 @@ e_cal_backend_class_init (ECalBackendClass *class)
                NULL, NULL, NULL,
                G_TYPE_NONE, 1,
                G_TYPE_STRING);
+
+       /**
+        * ECalBackend::shutdown:
+        * @backend: the #ECalBackend which emitted the signal
+        *
+        * Emitted when the last client destroys its #ECalClient for
+        * @backend.  This signals the @backend to begin final cleanup
+        * tasks such as synchronizing data to permanent storage.
+        *
+        * Since: 3.10
+        **/
+       signals[SHUTDOWN] = g_signal_new (
+               "shutdown",
+               G_OBJECT_CLASS_TYPE (object_class),
+               G_SIGNAL_RUN_LAST,
+               G_STRUCT_OFFSET (ECalBackendClass, shutdown),
+               NULL, NULL, NULL,
+               G_TYPE_NONE, 0);
 }
 
 static void
diff --git a/calendar/libedata-cal/e-cal-backend.h b/calendar/libedata-cal/e-cal-backend.h
index eb9754f..0eb5d3d 100644
--- a/calendar/libedata-cal/e-cal-backend.h
+++ b/calendar/libedata-cal/e-cal-backend.h
@@ -208,6 +208,7 @@ struct _ECalBackendClass {
        /* Signals */
        void            (*closed)               (ECalBackend *backend,
                                                 const gchar *sender);
+       void            (*shutdown)             (ECalBackend *backend);
 };
 
 GType          e_cal_backend_get_type          (void) G_GNUC_CONST;
diff --git a/calendar/libedata-cal/e-data-cal-factory.c b/calendar/libedata-cal/e-data-cal-factory.c
index 61e7514..87cdc70 100644
--- a/calendar/libedata-cal/e-data-cal-factory.c
+++ b/calendar/libedata-cal/e-data-cal-factory.c
@@ -85,6 +85,25 @@ watched_names_value_free (gpointer value)
 }
 
 static void
+data_cal_factory_toggle_notify_cb (gpointer data,
+                                   GObject *backend,
+                                   gboolean is_last_ref)
+{
+       if (is_last_ref) {
+               /* Take a strong reference before removing the
+                * toggle reference, to keep the backend alive. */
+               g_object_ref (backend);
+
+               g_object_remove_toggle_ref (
+                       backend, data_cal_factory_toggle_notify_cb, data);
+
+               g_signal_emit_by_name (backend, "shutdown");
+
+               g_object_unref (backend);
+       }
+}
+
+static void
 data_cal_factory_connections_add (EDataCalFactory *factory,
                                   const gchar *name,
                                   ECalBackend *backend)
@@ -349,6 +368,14 @@ data_cal_factory_open (EDataCalFactory *factory,
                        connection, object_path, error);
 
                if (data_cal != NULL) {
+                       /* Install a toggle reference on the backend
+                        * so we can signal it to shut down once all
+                        * client connections are closed. */
+                       g_object_add_toggle_ref (
+                               G_OBJECT (backend),
+                               data_cal_factory_toggle_notify_cb,
+                               NULL);
+
                        g_signal_connect_object (
                                backend, "closed",
                                G_CALLBACK (data_cal_factory_closed_cb),
diff --git a/configure.ac b/configure.ac
index cbf3441..4bae0c9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -114,7 +114,7 @@ LIBECAL_CURRENT=16
 LIBECAL_REVISION=0
 LIBECAL_AGE=0
 
-LIBEDATACAL_CURRENT=22
+LIBEDATACAL_CURRENT=23
 LIBEDATACAL_REVISION=0
 LIBEDATACAL_AGE=0