Renamed from backend_destroy_cb. Now we use it for the "last_client_gone"

2000-04-25  Federico Mena Quintero  <federico@helixcode.com>

	* pcs/cal-factory.c (backend_last_client_gone_cb): Renamed from
	backend_destroy_cb.  Now we use it for the "last_client_gone"
	signal from the backend.  Also, unref the backend to destroy it.
	(add_backend): Connect to the "last_client_gone" signal of the
	backend.
	(cal_factory_get_n_backends): New function to query the number of
	running backends.

	* pcs/cal-backend.c (cal_backend_class_init): Register the new
	"last_client_gone" signal.  It is emitted when the last Cal client
	goes away.  It is used to notify the factory when a backend may be
	safely destroyed.
	(cal_destroy_cb): Emit the "last_client_gone" signal when the last
	client disconnects from the backend.

svn path=/trunk/; revision=2619

5 files changed, 82 insertions, 10 deletions

diff --git a/calendar/ChangeLog b/calendar/ChangeLog
index ec34110476..dee7f11841 100644
--- a/calendar/ChangeLog
+++ b/calendar/ChangeLog
@@ -1,3 +1,20 @@
+2000-04-25  Federico Mena Quintero  <federico@helixcode.com>
+
+	* pcs/cal-factory.c (backend_last_client_gone_cb): Renamed from
+	backend_destroy_cb.  Now we use it for the "last_client_gone"
+	signal from the backend.  Also, unref the backend to destroy it.
+	(add_backend): Connect to the "last_client_gone" signal of the
+	backend.
+	(cal_factory_get_n_backends): New function to query the number of
+	running backends.
+
+	* pcs/cal-backend.c (cal_backend_class_init): Register the new
+	"last_client_gone" signal.  It is emitted when the last Cal client
+	goes away.  It is used to notify the factory when a backend may be
+	safely destroyed.
+	(cal_destroy_cb): Emit the "last_client_gone" signal when the last
+	client disconnects from the backend.
+
 2000-04-25  Seth Alves  <alves@hungry.com>
 
 	* gui/e-day-view.c (e_day_view_find_event_from_ico): compare
diff --git a/calendar/pcs/cal-backend.c b/calendar/pcs/cal-backend.c
index 4d0e659037..364a4670c6 100644
--- a/calendar/pcs/cal-backend.c
+++ b/calendar/pcs/cal-backend.c
@@ -61,12 +61,20 @@ typedef struct {
 
 
 
+/* Signal IDs */
+enum {
+	LAST_CLIENT_GONE,
+	LAST_SIGNAL
+};
+
 static void cal_backend_class_init (CalBackendClass *class);
 static void cal_backend_init (CalBackend *backend);
 static void cal_backend_destroy (GtkObject *object);
 
 static GtkObjectClass *parent_class;
 
+static guint cal_backend_signals[LAST_SIGNAL];
+
 
 
 /**
@@ -112,6 +120,16 @@ cal_backend_class_init (CalBackendClass *class)
 
 	parent_class = gtk_type_class (GTK_TYPE_OBJECT);
 
+	cal_backend_signals[LAST_CLIENT_GONE] =
+		gtk_signal_new ("last_client_gone",
+				GTK_RUN_FIRST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (CalBackendClass, last_client_gone),
+				gtk_marshal_NONE__NONE,
+				GTK_TYPE_NONE, 0);
+
+	gtk_object_class_add_signals (object_class, cal_backend_signals, LAST_SIGNAL);
+
 	object_class->destroy = cal_backend_destroy;
 }
 
@@ -128,7 +146,8 @@ cal_backend_init (CalBackend *backend)
 	priv->format = CAL_VCAL;
 }
 
-static void save_to_vcal (CalBackend *backend, char *fname)
+static void
+save_to_vcal (CalBackend *backend, char *fname)
 {
 	FILE *fp;
 	CalBackendPrivate *priv = backend->priv;
@@ -174,7 +193,6 @@ static void save_to_vcal (CalBackend *backend, char *fname)
 	cleanStrTbl ();
 }
 
-
 /* Saves a calendar */
 static void
 save (CalBackend *backend)
@@ -547,12 +565,11 @@ cal_destroy_cb (GtkObject *object, gpointer data)
 	priv->clients = g_list_remove_link (priv->clients, l);
 	g_list_free_1 (l);
 
-	/* When all clients go away, the backend can go away, too.  Commit
-         * suicide here.
+	/* When all clients go away, notify the parent factory about it so that
+	 * it may decide whether to kill the backend or not.
 	 */
-
 	if (!priv->clients)
-		gtk_object_unref (GTK_OBJECT (backend));
+		gtk_signal_emit (GTK_OBJECT (backend), cal_backend_signals[LAST_CLIENT_GONE]);
 }
 
 /**
diff --git a/calendar/pcs/cal-backend.h b/calendar/pcs/cal-backend.h
index af487f7551..e5102bf8bc 100644
--- a/calendar/pcs/cal-backend.h
+++ b/calendar/pcs/cal-backend.h
@@ -55,6 +55,9 @@ struct _CalBackend {
 
 struct _CalBackendClass {
 	GtkObjectClass parent_class;
+
+	/* Notification signals */
+	void (* last_client_gone) (CalBackend *backend);
 };
 
 typedef enum {
diff --git a/calendar/pcs/cal-factory.c b/calendar/pcs/cal-factory.c
index 63f6eb22c6..b89d5c450e 100644
--- a/calendar/pcs/cal-factory.c
+++ b/calendar/pcs/cal-factory.c
@@ -265,9 +265,9 @@ lookup_backend (CalFactory *factory, GnomeVFSURI *uri)
 	return backend;
 }
 
-/* Callback used when a backend is destroyed */
+/* Callback used when a backend loses its last connected client */
 static void
-backend_destroy_cb (GtkObject *object, gpointer data)
+backend_last_client_gone_cb (GtkObject *object, gpointer data)
 {
 	CalFactory *factory;
 	CalFactoryPrivate *priv;
@@ -294,6 +294,8 @@ backend_destroy_cb (GtkObject *object, gpointer data)
 	g_hash_table_remove (priv->backends, orig_uri);
 	gnome_vfs_uri_unref (orig_uri);
 
+	gtk_object_unref (GTK_OBJECT (backend));
+
 	/* Notify upstream if there are no more backends */
 
 	if (g_hash_table_size (priv->backends) == 0)
@@ -311,8 +313,8 @@ add_backend (CalFactory *factory, GnomeVFSURI *uri, CalBackend *backend)
 	gnome_vfs_uri_ref (uri);
 	g_hash_table_insert (priv->backends, uri, backend);
 
-	gtk_signal_connect (GTK_OBJECT (backend), "destroy",
-			    GTK_SIGNAL_FUNC (backend_destroy_cb),
+	gtk_signal_connect (GTK_OBJECT (backend), "last_client_gone",
+			    GTK_SIGNAL_FUNC (backend_last_client_gone_cb),
 			    factory);
 }
 
@@ -692,8 +694,38 @@ cal_factory_load (CalFactory *factory, const char *uri, Evolution_Calendar_Liste
 	queue_load_create_job (factory, uri, listener, load_fn);
 }
 
+/**
+ * cal_factory_create:
+ * @factory: A calendar factory.
+ * @uri: URI of calendar to create.
+ * @listener: Listener for notification of the create result.
+ * 
+ * Initiates a create request in a calendar factory.  A calendar will be created
+ * asynchronously and the result code will be reported to the specified
+ * listener.
+ **/
 void
 cal_factory_create (CalFactory *factory, const char *uri, Evolution_Calendar_Listener listener)
 {
 	queue_load_create_job (factory, uri, listener, create_fn);
 }
+
+/**
+ * cal_factory_get_n_backends:
+ * @factory: A calendar factory.
+ * 
+ * Queries the number of running calendar backends in a calendar factory.
+ * 
+ * Return value: Number of running backends.
+ **/
+int
+cal_factory_get_n_backends (CalFactory *factory)
+{
+	CalFactoryPrivate *priv;
+
+	g_return_val_if_fail (factory != NULL, -1);
+	g_return_val_if_fail (IS_CAL_FACTORY (factory), -1);
+
+	priv = factory->priv;
+	return g_hash_table_size (priv->backends);
+}
diff --git a/calendar/pcs/cal-factory.h b/calendar/pcs/cal-factory.h
index 7100a35d69..85435e45ae 100644
--- a/calendar/pcs/cal-factory.h
+++ b/calendar/pcs/cal-factory.h
@@ -50,6 +50,7 @@ struct _CalFactory {
 struct _CalFactoryClass {
 	BonoboObjectClass parent_class;
 
+	/* Notification signals */
 	void (* last_calendar_gone) (CalFactory *factory);
 };
 
@@ -63,6 +64,8 @@ CalFactory *cal_factory_new (void);
 void cal_factory_load (CalFactory *factory, const char *uri, Evolution_Calendar_Listener listener);
 void cal_factory_create (CalFactory *factory, const char *uri, Evolution_Calendar_Listener listener);
 
+int cal_factory_get_n_backends (CalFactory *factory);
+
 POA_Evolution_Calendar_CalFactory__epv *cal_factory_get_epv (void);