+ fn remove_stale_resolved_payments(&self) {
+ // If an outbound payment was completed, and no pending HTLCs remain, we should remove it
+ // from the map. However, if we did that immediately when the last payment HTLC is claimed,
+ // this could race the user making a duplicate send_payment call and our idempotency
+ // guarantees would be violated. Instead, we wait a few timer ticks to do the actual
+ // removal. This should be more than sufficient to ensure the idempotency of any
+ // `send_payment` calls that were made at the same time the `PaymentSent` event was being
+ // processed.
+ let mut pending_outbound_payments = self.pending_outbound_payments.lock().unwrap();
+ let pending_events = self.pending_events.lock().unwrap();
+ pending_outbound_payments.retain(|payment_id, payment| {
+ if let PendingOutboundPayment::Fulfilled { session_privs, timer_ticks_without_htlcs, .. } = payment {
+ let mut no_remaining_entries = session_privs.is_empty();
+ if no_remaining_entries {
+ for ev in pending_events.iter() {
+ match ev {
+ events::Event::PaymentSent { payment_id: Some(ev_payment_id), .. } |
+ events::Event::PaymentPathSuccessful { payment_id: ev_payment_id, .. } |
+ events::Event::PaymentPathFailed { payment_id: Some(ev_payment_id), .. } => {
+ if payment_id == ev_payment_id {
+ no_remaining_entries = false;
+ break;
+ }
+ },
+ _ => {},
+ }
+ }
+ }
+ if no_remaining_entries {
+ *timer_ticks_without_htlcs += 1;
+ *timer_ticks_without_htlcs <= IDEMPOTENCY_TIMEOUT_TICKS
+ } else {
+ *timer_ticks_without_htlcs = 0;
+ true
+ }
+ } else { true }
+ });
+ }
+