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

[Matthew Barnes <mbarnes src gnome org>]

commit e4d5ad0ca046ab0b4541f762535b333e7d846234
Author: Matthew Barnes <mbarnes redhat com>
Date:   Thu Aug 15 17:00:56 2013 -0400

    EBookBackend: 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 EBookBackendClass, and therefore requires a
    libedata-book soname bump.

 addressbook/libedata-book/e-book-backend.c      |   33 +++++++++++++++++++++++
 addressbook/libedata-book/e-book-backend.h      |    1 +
 addressbook/libedata-book/e-data-book-factory.c |   27 ++++++++++++++++++
 configure.ac                                    |    2 +-
 4 files changed, 62 insertions(+), 1 deletions(-)
---
diff --git a/addressbook/libedata-book/e-book-backend.c b/addressbook/libedata-book/e-book-backend.c
index fe03891..1344423 100644
--- a/addressbook/libedata-book/e-book-backend.c
+++ b/addressbook/libedata-book/e-book-backend.c
@@ -91,6 +91,7 @@ enum {
 
 enum {
        CLOSED,
+       SHUTDOWN,
        LAST_SIGNAL
 };
 
@@ -536,6 +537,19 @@ book_backend_notify_update (EBookBackend *backend,
 }
 
 static void
+book_backend_shutdown (EBookBackend *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
 e_book_backend_class_init (EBookBackendClass *class)
 {
        GObjectClass *object_class;
@@ -556,6 +570,7 @@ e_book_backend_class_init (EBookBackendClass *class)
        class->get_backend_property = book_backend_get_backend_property;
        class->get_contact_list_uids_sync = book_backend_get_contact_list_uids_sync;
        class->notify_update = book_backend_notify_update;
+       class->shutdown = book_backend_shutdown;
 
        g_object_class_install_property (
                object_class,
@@ -608,6 +623,24 @@ e_book_backend_class_init (EBookBackendClass *class)
                NULL, NULL, NULL,
                G_TYPE_NONE, 1,
                G_TYPE_STRING);
+
+       /**
+        * EBookBackend::shutdown:
+        * @backend: the #EBookBackend which emitted the signal
+        *
+        * Emitted when the last client destroys its #EBookClient 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 (EBookBackendClass, shutdown),
+               NULL, NULL, NULL,
+               G_TYPE_NONE, 0);
 }
 
 static void
diff --git a/addressbook/libedata-book/e-book-backend.h b/addressbook/libedata-book/e-book-backend.h
index a4668d1..75761e8 100644
--- a/addressbook/libedata-book/e-book-backend.h
+++ b/addressbook/libedata-book/e-book-backend.h
@@ -214,6 +214,7 @@ struct _EBookBackendClass {
        /* Signals */
        void            (*closed)               (EBookBackend *backend,
                                                 const gchar *sender);
+       void            (*shutdown)             (EBookBackend *backend);
 };
 
 GType          e_book_backend_get_type         (void) G_GNUC_CONST;
diff --git a/addressbook/libedata-book/e-data-book-factory.c b/addressbook/libedata-book/e-data-book-factory.c
index 19a32d5..7017aa1 100644
--- a/addressbook/libedata-book/e-data-book-factory.c
+++ b/addressbook/libedata-book/e-data-book-factory.c
@@ -79,6 +79,25 @@ watched_names_value_free (gpointer value)
 }
 
 static void
+data_book_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_book_factory_toggle_notify_cb, data);
+
+               g_signal_emit_by_name (backend, "shutdown");
+
+               g_object_unref (backend);
+       }
+}
+
+static void
 data_book_factory_connections_add (EDataBookFactory *factory,
                                    const gchar *name,
                                    EBookBackend *backend)
@@ -343,6 +362,14 @@ data_book_factory_open (EDataBookFactory *factory,
                        connection, object_path, error);
 
                if (data_book != 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_book_factory_toggle_notify_cb,
+                               NULL);
+
                        g_signal_connect_object (
                                backend, "closed",
                                G_CALLBACK (data_book_factory_closed_cb),
diff --git a/configure.ac b/configure.ac
index 872c7b4..cbf3441 100644
--- a/configure.ac
+++ b/configure.ac
@@ -118,7 +118,7 @@ LIBEDATACAL_CURRENT=22
 LIBEDATACAL_REVISION=0
 LIBEDATACAL_AGE=0
 
-LIBEDATABOOK_CURRENT=19
+LIBEDATABOOK_CURRENT=20
 LIBEDATABOOK_REVISION=0
 LIBEDATABOOK_AGE=0