core: add version-id to NMActiveConnection

This field will be later used by NMDevice's Reapply and
GetAppliedConnection methods. The usecase is to first fetch
the currently applied connection, adjust it and reapply it.
Using the version-id, a concurrent modification can be detected
and Reapply can reject the invocation.

3 files changed, 54 insertions, 5 deletions

diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index 29ebe0e759..c33a19db65 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -7181,6 +7181,7 @@ reapply_connection (NMDevice *self,
 	NMConnection *con_old, *con_new;
 	NMSettingIPConfig *s_ip4_old, *s_ip4_new;
 	NMSettingIPConfig *s_ip6_old, *s_ip6_new;
+	guint64 version_id;
 
 	if (priv->state != NM_DEVICE_STATE_ACTIVATED) {
 		g_set_error_literal (error,
@@ -7212,12 +7213,17 @@ reapply_connection (NMDevice *self,
 	                               NM_SETTING_CONNECTION_METERED))
 		return FALSE;
 
-	_LOGD (LOGD_DEVICE, "reapply");
-
 	/**************************************************************************
 	 * Update applied connection
 	 *************************************************************************/
 
+	if (diffs)
+		nm_active_connection_version_id_bump ((NMActiveConnection *) priv->act_request);
+
+	_LOGD (LOGD_DEVICE, "reapply (version-id %llu%s)",
+	       (long long unsigned) nm_active_connection_version_id_get (((NMActiveConnection *) priv->act_request)),
+	       diffs ? "" : " (unmodified)");
+
 	if (diffs) {
 		con_old = applied_clone  = nm_simple_connection_new_clone (applied);
 		con_new = applied;
@@ -9218,6 +9224,7 @@ nm_device_reapply_settings_immediately (NMDevice *self)
 	NMSettingConnection *s_con_applied;
 	const char *zone;
 	NMMetered metered;
+	guint64 version_id;
 
 	g_return_if_fail (NM_IS_DEVICE (self));
 
@@ -9240,7 +9247,8 @@ nm_device_reapply_settings_immediately (NMDevice *self)
 	if (g_strcmp0 ((zone = nm_setting_connection_get_zone (s_con_settings)),
 	               nm_setting_connection_get_zone (s_con_applied)) != 0) {
 
-		_LOGD (LOGD_DEVICE, "reapply setting: zone = %s%s%s", NM_PRINT_FMT_QUOTE_STRING (zone));
+		version_id = nm_active_connection_version_id_bump ((NMActiveConnection *) self->priv->act_request);
+		_LOGD (LOGD_DEVICE, "reapply setting: zone = %s%s%s (version-id %llu)", NM_PRINT_FMT_QUOTE_STRING (zone), (long long unsigned) version_id);
 
 		g_object_set (G_OBJECT (s_con_applied),
 		              NM_SETTING_CONNECTION_ZONE, zone,
@@ -9251,7 +9259,8 @@ nm_device_reapply_settings_immediately (NMDevice *self)
 
 	if ((metered = nm_setting_connection_get_metered (s_con_settings)) != nm_setting_connection_get_metered (s_con_applied)) {
 
-		_LOGD (LOGD_DEVICE, "reapply setting: metered = %d", (int) metered);
+		version_id = nm_active_connection_version_id_bump ((NMActiveConnection *) self->priv->act_request);
+		_LOGD (LOGD_DEVICE, "reapply setting: metered = %d (version-id %llu)", (int) metered, (long long unsigned) version_id);
 
 		g_object_set (G_OBJECT (s_con_applied),
 		              NM_SETTING_CONNECTION_METERED, metered,
diff --git a/src/nm-active-connection.c b/src/nm-active-connection.c
index 91068e56a7..f7506022a1 100644
--- a/src/nm-active-connection.c
+++ b/src/nm-active-connection.c
@@ -46,6 +46,8 @@ typedef struct {
 	char *specific_object;
 	NMDevice *device;
 
+	guint64 version_id;
+
 	char *pending_activation_id;
 
 	gboolean is_default;
@@ -796,10 +798,45 @@ nm_active_connection_authorize (NMActiveConnection *self,
 
 /****************************************************************/
 
+static guint64
+_version_id_new (void)
+{
+	static guint64 id = 0;
+
+	return ++id;
+}
+
+guint64
+nm_active_connection_version_id_get (NMActiveConnection *self)
+{
+	g_return_val_if_fail (NM_IS_ACTIVE_CONNECTION (self), 0);
+
+	return NM_ACTIVE_CONNECTION_GET_PRIVATE (self)->version_id;
+}
+
+guint64
+nm_active_connection_version_id_bump (NMActiveConnection *self)
+{
+	NMActiveConnectionPrivate *priv;
+
+	g_return_val_if_fail (NM_IS_ACTIVE_CONNECTION (self), 0);
+
+	priv = NM_ACTIVE_CONNECTION_GET_PRIVATE  (self);
+	priv->version_id = _version_id_new ();
+	_LOGT ("new version-id %llu", (long long unsigned) priv->version_id);
+	return priv->version_id;
+}
+
+/****************************************************************/
+
 static void
 nm_active_connection_init (NMActiveConnection *self)
 {
+	NMActiveConnectionPrivate *priv = NM_ACTIVE_CONNECTION_GET_PRIVATE (self);
+
 	_LOGT ("creating");
+
+	priv->version_id = _version_id_new ();
 }
 
 static void
@@ -810,7 +847,7 @@ constructed (GObject *object)
 
 	G_OBJECT_CLASS (nm_active_connection_parent_class)->constructed (object);
 
-	_LOGD ("constructed (%s)", G_OBJECT_TYPE_NAME (self));
+	_LOGD ("constructed (%s, version-id %llu)", G_OBJECT_TYPE_NAME (self), (long long unsigned) priv->version_id);
 
 	g_return_if_fail (priv->subject);
 }
diff --git a/src/nm-active-connection.h b/src/nm-active-connection.h
index f57f2081f1..a7b3d0cd34 100644
--- a/src/nm-active-connection.h
+++ b/src/nm-active-connection.h
@@ -83,6 +83,9 @@ typedef struct {
 	                                NMMetered new_value);
 } NMActiveConnectionClass;
 
+guint64 nm_active_connection_version_id_get (NMActiveConnection *self);
+guint64 nm_active_connection_version_id_bump (NMActiveConnection *self);
+
 GType         nm_active_connection_get_type (void);
 
 typedef void (*NMActiveConnectionAuthResultFunc) (NMActiveConnection *self,