Account for leftover fee budget when retrying via `check_retry_payment`

diff --git a/lightning/src/ln/outbound_payment.rs b/lightning/src/ln/outbound_payment.rs
index e06ba8d853982ccbd1c3a0c79e2815586158ffcf..5859cbe54aa32e1850607b32218fc03bedab6dd8 100644 (file)
--- a/lightning/src/ln/outbound_payment.rs
+++ b/lightning/src/ln/outbound_payment.rs
@@ -215,11 +215,19 @@ impl PendingOutboundPayment {
                                PendingOutboundPayment::InvoiceReceived { .. } => { debug_assert!(false); false },
                };
                if remove_res {
-                       if let PendingOutboundPayment::Retryable { ref mut pending_amt_msat, ref mut pending_fee_msat, .. } = self {
-                               let path = path.expect("Fulfilling a payment should always come with a path");
+                       if let PendingOutboundPayment::Retryable {
+                               ref mut pending_amt_msat, ref mut pending_fee_msat,
+                               ref mut remaining_max_total_routing_fee_msat, ..
+                       } = self {
+                               let path = path.expect("Removing a failed payment should always come with a path");
                                *pending_amt_msat -= path.final_value_msat();
+                               let path_fee_msat = path.fee_msat();
                                if let Some(fee_msat) = pending_fee_msat.as_mut() {
-                                       *fee_msat -= path.fee_msat();
+                                       *fee_msat -= path_fee_msat;
+                               }
+
+                               if let Some(max_total_routing_fee_msat) = remaining_max_total_routing_fee_msat.as_mut() {
+                                       *max_total_routing_fee_msat = max_total_routing_fee_msat.saturating_add(path_fee_msat);
                                }
                        }
                }
@@ -238,11 +246,19 @@ impl PendingOutboundPayment {
                        PendingOutboundPayment::Abandoned { .. } => false,
                };
                if insert_res {
-                       if let PendingOutboundPayment::Retryable { ref mut pending_amt_msat, ref mut pending_fee_msat, .. } = self {
-                               *pending_amt_msat += path.final_value_msat();
-                               if let Some(fee_msat) = pending_fee_msat.as_mut() {
-                                       *fee_msat += path.fee_msat();
-                               }
+                       if let PendingOutboundPayment::Retryable {
+                               ref mut pending_amt_msat, ref mut pending_fee_msat,
+                               ref mut remaining_max_total_routing_fee_msat, .. 
+                       } = self {
+                                       *pending_amt_msat += path.final_value_msat();
+                                       let path_fee_msat = path.fee_msat();
+                                       if let Some(fee_msat) = pending_fee_msat.as_mut() {
+                                               *fee_msat += path_fee_msat;
+                                       }
+
+                                       if let Some(max_total_routing_fee_msat) = remaining_max_total_routing_fee_msat.as_mut() {
+                                               *max_total_routing_fee_msat = max_total_routing_fee_msat.saturating_sub(path_fee_msat);
+                                       }
                        }
                }
                insert_res
@@ -1573,7 +1589,7 @@ impl OutboundPayments {
                                is_retryable_now = false;
                        }
                        if payment.get().remaining_parts() == 0 {
-                               if let PendingOutboundPayment::Abandoned { payment_hash, reason, .. }= payment.get() {
+                               if let PendingOutboundPayment::Abandoned { payment_hash, reason, .. } = payment.get() {
                                        if !payment_is_probe {
                                                full_failure_ev = Some(events::Event::PaymentFailed {
                                                        payment_id: *payment_id,