--- /dev/null
+namespace org { namespace ldk { namespace enums {/**
+ * An enum representing the status of a channel monitor update persistence.
+ */
+public enum ChannelMonitorUpdateStatus {
+ /**
+ * The update has been durably persisted and all copies of the relevant [`ChannelMonitor`]
+ * have been updated.
+ *
+ * This includes performing any `fsync()` calls required to ensure the update is guaranteed to
+ * be available on restart even if the application crashes.
+ */
+ LDKChannelMonitorUpdateStatus_Completed,
+ /**
+ * Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
+ * our state failed, but is expected to succeed at some point in the future).
+ *
+ * Such a failure will \"freeze\" a channel, preventing us from revoking old states or
+ * submitting new commitment transactions to the counterparty. Once the update(s) which failed
+ * have been successfully applied, a [`MonitorEvent::Completed`] can be used to restore the
+ * channel to an operational state.
+ *
+ * Note that a given [`ChannelManager`] will *never* re-generate a [`ChannelMonitorUpdate`].
+ * If you return this error you must ensure that it is written to disk safely before writing
+ * the latest [`ChannelManager`] state, or you should return [`PermanentFailure`] instead.
+ *
+ * Even when a channel has been \"frozen\", updates to the [`ChannelMonitor`] can continue to
+ * occur (e.g. if an inbound HTLC which we forwarded was claimed upstream, resulting in us
+ * attempting to claim it on this channel) and those updates must still be persisted.
+ *
+ * No updates to the channel will be made which could invalidate other [`ChannelMonitor`]s
+ * until a [`MonitorEvent::Completed`] is provided, even if you return no error on a later
+ * monitor update for the same channel.
+ *
+ * For deployments where a copy of ChannelMonitors and other local state are backed up in a
+ * remote location (with local copies persisted immediately), it is anticipated that all
+ * updates will return [`InProgress`] until the remote copies could be updated.
+ *
+ * [`PermanentFailure`]: ChannelMonitorUpdateStatus::PermanentFailure
+ * [`InProgress`]: ChannelMonitorUpdateStatus::InProgress
+ * [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
+ */
+ LDKChannelMonitorUpdateStatus_InProgress,
+ /**
+ * Used to indicate no further channel monitor updates will be allowed (likely a disk failure
+ * or a remote copy of this [`ChannelMonitor`] is no longer reachable and thus not updatable).
+ *
+ * When this is returned, [`ChannelManager`] will force-close the channel but *not* broadcast
+ * our current commitment transaction. This avoids a dangerous case where a local disk failure
+ * (e.g. the Linux-default remounting of the disk as read-only) causes [`PermanentFailure`]s
+ * for all monitor updates. If we were to broadcast our latest commitment transaction and then
+ * restart, we could end up reading a previous [`ChannelMonitor`] and [`ChannelManager`],
+ * revoking our now-broadcasted state before seeing it confirm and losing all our funds.
+ *
+ * Note that this is somewhat of a tradeoff - if the disk is really gone and we may have lost
+ * the data permanently, we really should broadcast immediately. If the data can be recovered
+ * with manual intervention, we'd rather close the channel, rejecting future updates to it,
+ * and broadcast the latest state only if we have HTLCs to claim which are timing out (which
+ * we do as long as blocks are connected).
+ *
+ * In order to broadcast the latest local commitment transaction, you'll need to call
+ * [`ChannelMonitor::get_latest_holder_commitment_txn`] and broadcast the resulting
+ * transactions once you've safely ensured no further channel updates can be generated by your
+ * [`ChannelManager`].
+ *
+ * Note that at least one final [`ChannelMonitorUpdate`] may still be provided, which must
+ * still be processed by a running [`ChannelMonitor`]. This final update will mark the
+ * [`ChannelMonitor`] as finalized, ensuring no further updates (e.g. revocation of the latest
+ * commitment transaction) are allowed.
+ *
+ * Note that even if you return a [`PermanentFailure`] due to unavailability of secondary
+ * [`ChannelMonitor`] copies, you should still make an attempt to store the update where
+ * possible to ensure you can claim HTLC outputs on the latest commitment transaction
+ * broadcasted later.
+ *
+ * In case of distributed watchtowers deployment, the new version must be written to disk, as
+ * state may have been stored but rejected due to a block forcing a commitment broadcast. This
+ * storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
+ * lagging behind on block processing.
+ *
+ * [`PermanentFailure`]: ChannelMonitorUpdateStatus::PermanentFailure
+ * [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
+ */
+ LDKChannelMonitorUpdateStatus_PermanentFailure,
+}} } }
projects / ldk-java / blobdiff