Convert NetworkManager integration to an EShell extension.

This demonstrates how to extend EShell without having to modify and
recompile e-shell.c.  If NetworkManager integration is enabled, the
extension is loaded automatically when the EShell is created.

The same pattern can be applied to integrate other network monitoring
software like ConnMan or Microsoft's Wireless Zero Configuration.

3 files changed, 279 insertions, 1 deletions

diff --git a/modules/Makefile.am b/modules/Makefile.am
index f792a4d9ee..0b6ccf22ec 100644
--- a/modules/Makefile.am
+++ b/modules/Makefile.am
@@ -6,6 +6,17 @@ if ENABLE_PYTHON
 PYTHON_DIR = plugin-python
 endif
 
-SUBDIRS = addressbook calendar mail plugin-lib $(MONO_DIR) $(PYTHON_DIR)
+if ENABLE_NETWORK_MANAGER
+NETWORK_MANAGER_DIR = network-manager
+endif
+
+SUBDIRS = \
+	addressbook \
+	calendar \
+	mail \
+	plugin-lib \
+	$(MONO_DIR) \
+	$(PYTHON_DIR) \
+	$(NETWORK_MANAGER_DIR)
 
 -include $(top_srcdir)/git.mk
diff --git a/modules/network-manager/Makefile.am b/modules/network-manager/Makefile.am
new file mode 100644
index 0000000000..24cd80a246
--- /dev/null
+++ b/modules/network-manager/Makefile.am
@@ -0,0 +1,22 @@
+module_LTLIBRARIES = libevolution-module-network-manager.la
+
+libevolution_module_network_manager_la_CPPFLAGS =		\
+	$(AM_CPPFLAGS)						\
+	-I$(top_srcdir)						\
+	-DG_LOG_DOMAIN=\"evolution-network-manager\"		\
+	$(GNOME_PLATFORM_CFLAGS)				\
+	$(DBUS_GLIB_CFLAGS)					\
+	$(NM_CFLAGS)
+
+libevolution_module_network_manager_la_SOURCES =		\
+	evolution-network-manager.c
+
+libevolution_module_network_manager_la_LIBADD =			\
+	$(top_builddir)/shell/libeshell.la			\
+	$(GNOME_PLATFORM_LIBS)					\
+	$(DBUS_GLIB_LIBS)
+
+libevolution_module_network_manager_la_LDFLAGS =		\
+	-module -avoid-version $(NO_UNDEFINED)
+
+-include $(top_srcdir)/git.mk
diff --git a/modules/network-manager/evolution-network-manager.c b/modules/network-manager/evolution-network-manager.c
new file mode 100644
index 0000000000..7dc110f411
--- /dev/null
+++ b/modules/network-manager/evolution-network-manager.c
@@ -0,0 +1,245 @@
+/*
+ * evolution-network-manager.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with the program; if not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+#include <dbus/dbus.h>
+#include <dbus/dbus-glib.h>
+#include <dbus/dbus-glib-lowlevel.h>
+#include <NetworkManager/NetworkManager.h>
+
+#include <shell/e-shell.h>
+#include <e-util/e-extension.h>
+
+/* Standard GObject macros */
+#define E_TYPE_NETWORK_MANAGER \
+	(e_network_manager_get_type ())
+#define E_NETWORK_MANAGER(obj) \
+	(G_TYPE_CHECK_INSTANCE_CAST \
+	((obj), E_TYPE_NETWORK_MANAGER, ENetworkManager))
+
+typedef struct _ENetworkManager ENetworkManager;
+typedef struct _ENetworkManagerClass ENetworkManagerClass;
+
+struct _ENetworkManager {
+	EExtension parent;
+	DBusConnection *connection;
+};
+
+struct _ENetworkManagerClass {
+	EExtensionClass parent_class;
+};
+
+/* Module Entry Points */
+void e_module_load (GTypeModule *type_module);
+void e_module_unload (GTypeModule *type_module);
+
+/* Forward Declarations */
+GType e_network_manager_get_type (void);
+static gboolean network_manager_connect (ENetworkManager *extension);
+
+G_DEFINE_DYNAMIC_TYPE (ENetworkManager, e_network_manager, E_TYPE_EXTENSION)
+
+static EShell *
+network_manager_get_shell (ENetworkManager *extension)
+{
+	EExtensible *extensible;
+
+	extensible = e_extension_get_extensible (E_EXTENSION (extension));
+
+	return E_SHELL (extensible);
+}
+
+static DBusHandlerResult
+network_manager_monitor (DBusConnection *connection G_GNUC_UNUSED,
+                         DBusMessage *message,
+                         gpointer user_data)
+{
+	ENetworkManager *extension = user_data;
+	EShell *shell;
+	const gchar *path;
+	guint32 state;
+	DBusError error = DBUS_ERROR_INIT;
+
+	shell = network_manager_get_shell (extension);
+
+	path = dbus_message_get_path (message);
+
+	if (dbus_message_is_signal (message, DBUS_INTERFACE_LOCAL, "Disconnected") &&
+		g_strcmp0 (path, DBUS_PATH_LOCAL) == 0) {
+		dbus_connection_unref (extension->connection);
+		extension->connection = NULL;
+
+		g_timeout_add_seconds (
+			3, (GSourceFunc) network_manager_connect, extension);
+
+		return DBUS_HANDLER_RESULT_HANDLED;
+	}
+
+	if (!dbus_message_is_signal (message, NM_DBUS_INTERFACE, "StateChanged"))
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+
+	dbus_message_get_args (
+		message, &error,
+		DBUS_TYPE_UINT32, &state,
+		DBUS_TYPE_INVALID);
+
+	if (dbus_error_is_set (&error)) {
+		g_warning ("%s", error.message);
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+	}
+
+	switch (state) {
+		case NM_STATE_CONNECTED:
+			e_shell_set_network_available (shell, TRUE);
+			break;
+		case NM_STATE_ASLEEP:
+		case NM_STATE_DISCONNECTED:
+			e_shell_set_network_available (shell, FALSE);
+			break;
+		default:
+			break;
+	}
+
+	return DBUS_HANDLER_RESULT_HANDLED;
+}
+
+static void
+network_manager_check_initial_state (ENetworkManager *extension)
+{
+	EShell *shell;
+	DBusMessage *message = NULL;
+	DBusMessage *response = NULL;
+	guint32 state = -1;
+	DBusError error = DBUS_ERROR_INIT;
+
+	shell = network_manager_get_shell (extension);
+
+	message = dbus_message_new_method_call (
+		NM_DBUS_SERVICE, NM_DBUS_PATH, NM_DBUS_INTERFACE, "state");
+
+	/* XXX Assuming this should be safe to call synchronously. */
+	response = dbus_connection_send_with_reply_and_block (
+		extension->connection, message, 100, &error);
+
+	if (response != NULL) {
+		dbus_message_get_args (
+			response, &error, DBUS_TYPE_UINT32,
+			&state, DBUS_TYPE_INVALID);
+	} else {
+		g_warning ("%s", error.message);
+		dbus_error_free (&error);
+		return;
+	}
+
+	/* Update the state only in the absence of a network connection,
+	 * otherwise let the old state prevail. */
+	if (state == NM_STATE_ASLEEP || state == NM_STATE_DISCONNECTED)
+		e_shell_set_network_available (shell, FALSE);
+
+	dbus_message_unref (message);
+	dbus_message_unref (response);
+}
+
+static gboolean
+network_manager_connect (ENetworkManager *extension)
+{
+	DBusError error = DBUS_ERROR_INIT;
+
+	/* This is a timeout callback, so the return value denotes
+	 * whether to reschedule, not whether we're successful. */
+
+	if (extension->connection != NULL)
+		return FALSE;
+
+	extension->connection = dbus_bus_get (DBUS_BUS_SYSTEM, &error);
+	if (extension->connection == NULL) {
+		g_warning ("%s", error.message);
+		dbus_error_free (&error);
+		return TRUE;
+	}
+
+	dbus_connection_setup_with_g_main (extension->connection, NULL);
+	dbus_connection_set_exit_on_disconnect (extension->connection, FALSE);
+
+	if (!dbus_connection_add_filter (
+		extension->connection,
+		network_manager_monitor, extension, NULL))
+		goto fail;
+
+	network_manager_check_initial_state (extension);
+
+	dbus_bus_add_match (
+		extension->connection,
+		"type='signal',"
+		"interface='" NM_DBUS_INTERFACE "',"
+		"sender='" NM_DBUS_SERVICE "',"
+		"path='" NM_DBUS_PATH "'",
+		&error);
+	if (dbus_error_is_set (&error)) {
+		g_warning ("%s", error.message);
+		dbus_error_free (&error);
+		goto fail;
+	}
+
+	return FALSE;
+
+fail:
+	dbus_connection_unref (extension->connection);
+	extension->connection = NULL;
+
+	return TRUE;
+}
+
+static void
+network_manager_constructed (GObject *object)
+{
+	network_manager_connect (E_NETWORK_MANAGER (object));
+}
+
+static void
+e_network_manager_class_init (ENetworkManagerClass *class)
+{
+	GObjectClass *object_class;
+	EExtensionClass *extension_class;
+
+	object_class = G_OBJECT_CLASS (class);
+	object_class->constructed = network_manager_constructed;
+
+	extension_class = E_EXTENSION_CLASS (class);
+	extension_class->extensible_type = E_TYPE_SHELL;
+}
+
+static void
+e_network_manager_class_finalize (ENetworkManagerClass *class)
+{
+}
+
+static void
+e_network_manager_init (ENetworkManager *extension)
+{
+}
+
+G_MODULE_EXPORT void
+e_module_load (GTypeModule *type_module)
+{
+	e_network_manager_register_type (type_module);
+}
+
+G_MODULE_EXPORT void
+e_module_unload (GTypeModule *type_module)
+{
+}