From 025d787fd2ab6f3838405bdc342065bd6e2afec8 Mon Sep 17 00:00:00 2001 From: yyforyongyu Date: Sun, 17 Nov 2024 10:48:16 +0800 Subject: [PATCH] invoices: exit early when the subscriber chan is nil When calling `NotifyExitHopHtlc` it is allowed to pass a chan to subscribe to the HTLC's resolution when it's settled. However, this method will also return immediately if there's already a resolution, which means it behaves like a notifier and a getter. If the caller decides to only use the getter to do a non-blocking lookup, it can pass a nil subscriber chan to bypass the notification. --- contractcourt/mock_registry_test.go | 5 +++++ invoices/invoiceregistry.go | 6 +++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/contractcourt/mock_registry_test.go b/contractcourt/mock_registry_test.go index 5bba11afc..0530ab51d 100644 --- a/contractcourt/mock_registry_test.go +++ b/contractcourt/mock_registry_test.go @@ -29,6 +29,11 @@ func (r *mockRegistry) NotifyExitHopHtlc(payHash lntypes.Hash, wireCustomRecords lnwire.CustomRecords, payload invoices.Payload) (invoices.HtlcResolution, error) { + // Exit early if the notification channel is nil. + if hodlChan == nil { + return r.notifyResolution, r.notifyErr + } + r.notifyChan <- notifyExitHopData{ hodlChan: hodlChan, payHash: payHash, diff --git a/invoices/invoiceregistry.go b/invoices/invoiceregistry.go index f5a6c6a95..cc76d5aef 100644 --- a/invoices/invoiceregistry.go +++ b/invoices/invoiceregistry.go @@ -1275,7 +1275,11 @@ func (i *InvoiceRegistry) notifyExitHopHtlcLocked( invoiceToExpire = makeInvoiceExpiry(ctx.hash, invoice) } - i.hodlSubscribe(hodlChan, ctx.circuitKey) + // Subscribe to the resolution if the caller specified a + // notification channel. + if hodlChan != nil { + i.hodlSubscribe(hodlChan, ctx.circuitKey) + } default: panic("unknown action")