[PATCH] system-connections: restore previous connection settings if update failed by plugin

[Andrey Borzenkov <arvidjaar gmail com>]

Currently NM first updates in-memory connection and then requests
plugin to store definition. If plugin failed to store for whatever
reason we are left with new memory state and stale permanent copy.
What makes is worse, nm-connection-editor does not indicate any
error in this case, so user is unaware that all settings are lost
after NM is restarted.

Save connection copy before calling plugin and revert to it
if plugin indicated failure.

Signed-off-by: Andrey Borzenkov <arvidjaar gmail com>

---
 src/system-settings/nm-sysconfig-connection.c |   15 +++++++++++++--
 1 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/system-settings/nm-sysconfig-connection.c b/src/system-settings/nm-sysconfig-connection.c
index 73906d2..5159407 100644
--- a/src/system-settings/nm-sysconfig-connection.c
+++ b/src/system-settings/nm-sysconfig-connection.c
@@ -245,6 +245,9 @@ typedef struct {
 	/* Update */
 	NMConnection *connection;
 
+	/* Rollback */
+	NMConnection *old_connection;
+
 	/* Secrets */
 	char *setting_name;
 	char **hints;
@@ -270,6 +273,7 @@ polkit_call_new (NMSysconfigConnection *self,
 	call->context = context;
 	call->cancellable = g_cancellable_new ();
 	call->connection = connection;
+	call->old_connection = NULL;
 	call->setting_name = g_strdup (setting_name);
 	if (hints)
 		call->hints = g_strdupv ((char **) hints);
@@ -287,6 +291,8 @@ polkit_call_free (PolkitCall *call)
 {
 	if (call->connection)
 		g_object_unref (call->connection);
+	if (call->old_connection)
+		g_object_unref (call->old_connection);
 	g_free (call->setting_name);
 	if (call->hints)
 		g_strfreev (call->hints);
@@ -303,9 +309,11 @@ con_update_cb (NMSettingsConnectionInterface *connection,
 {
 	PolkitCall *call = user_data;
 
-	if (error)
+	if (error) {
+
+		nm_sysconfig_connection_update (call->self, call->old_connection, FALSE, NULL);
 		dbus_g_method_return_error (call->context, error);
-	else
+	} else
 		dbus_g_method_return (call->context);
 
 	polkit_call_free (call);
@@ -357,6 +365,9 @@ pk_update_cb (GObject *object, GAsyncResult *result, gpointer user_data)
 		goto out;
 	}
 
+	/* Save old connection so we can restore it later */
+	call->old_connection = nm_connection_duplicate (NM_CONNECTION (self));
+
 	/* Update our settings internally so the update() call will save the new
 	 * ones.  We don't let nm_sysconfig_connection_update() handle the update
 	 * signal since we need our own callback after the update is done.
-- 
tg: (f6f8ef2..) u/conn-update (depends on: upstream/master)