diff --git a/invoices/invoiceregistry.go b/invoices/invoiceregistry.go index e83a21b6..d7ac13f7 100644 --- a/invoices/invoiceregistry.go +++ b/invoices/invoiceregistry.go @@ -807,8 +807,53 @@ func (i *InvoiceRegistry) NotifyExitHopHtlc(rHash lntypes.Hash, } } + // Execute locked notify exit hop logic. i.Lock() - defer i.Unlock() + resolution, err := i.notifyExitHopHtlcLocked(&updateCtx, hodlChan) + i.Unlock() + if err != nil { + return nil, err + } + + switch r := resolution.(type) { + + // A direct resolution was received for this htlc. + case *HtlcResolution: + return r, nil + + // The htlc is held. Start a timer outside the lock if the htlc should + // be auto-released, because otherwise a deadlock may happen with the + // main event loop. + case *acceptResolution: + if r.autoRelease { + err := i.startHtlcTimer(rHash, circuitKey, r.acceptTime) + if err != nil { + return nil, err + } + } + + return nil, nil + + default: + return nil, errors.New("invalid resolution type") + } +} + +// acceptResolution is returned when the htlc should be held. +type acceptResolution struct { + // autoRelease signals that the htlc should be automatically released + // after a timeout. + autoRelease bool + + // acceptTime is the time at which this htlc was accepted. + acceptTime time.Time +} + +// notifyExitHopHtlcLocked is the internal implementation of NotifyExitHopHtlc +// that should be executed inside the registry lock. +func (i *InvoiceRegistry) notifyExitHopHtlcLocked( + ctx *invoiceUpdateCtx, hodlChan chan<- interface{}) ( + interface{}, error) { // We'll attempt to settle an invoice matching this rHash on disk (if // one exists). The callback will update the invoice state and/or htlcs. @@ -817,11 +862,11 @@ func (i *InvoiceRegistry) NotifyExitHopHtlc(rHash lntypes.Hash, updateSubscribers bool ) invoice, err := i.cdb.UpdateInvoice( - rHash, + ctx.hash, func(inv *channeldb.Invoice) ( *channeldb.InvoiceUpdateDesc, error) { - updateDesc, res, err := updateInvoice(&updateCtx, inv) + updateDesc, res, err := updateInvoice(ctx, inv) if err != nil { return nil, err } @@ -841,29 +886,30 @@ func (i *InvoiceRegistry) NotifyExitHopHtlc(rHash lntypes.Hash, // If the invoice was not found, return a failure resolution // with an invoice not found result. return NewFailureResolution( - circuitKey, currentHeight, ResultInvoiceNotFound, + ctx.circuitKey, ctx.currentHeight, + ResultInvoiceNotFound, ), nil case nil: default: - updateCtx.log(err.Error()) + ctx.log(err.Error()) return nil, err } - updateCtx.log(result.String()) + ctx.log(result.String()) if updateSubscribers { - i.notifyClients(rHash, invoice, invoice.State) + i.notifyClients(ctx.hash, invoice, invoice.State) } // Inspect latest htlc state on the invoice. - invoiceHtlc, ok := invoice.Htlcs[circuitKey] + invoiceHtlc, ok := invoice.Htlcs[ctx.circuitKey] // If it isn't recorded, cancel htlc. if !ok { return NewFailureResolution( - circuitKey, currentHeight, result, + ctx.circuitKey, ctx.currentHeight, result, ), nil } @@ -876,7 +922,7 @@ func (i *InvoiceRegistry) NotifyExitHopHtlc(rHash lntypes.Hash, switch invoiceHtlc.State { case channeldb.HtlcStateCanceled: return NewFailureResolution( - circuitKey, acceptHeight, result, + ctx.circuitKey, acceptHeight, result, ), nil case channeldb.HtlcStateSettled: @@ -902,27 +948,25 @@ func (i *InvoiceRegistry) NotifyExitHopHtlc(rHash lntypes.Hash, } resolution := NewSettleResolution( - invoice.Terms.PaymentPreimage, circuitKey, + invoice.Terms.PaymentPreimage, ctx.circuitKey, acceptHeight, result, ) return resolution, nil case channeldb.HtlcStateAccepted: - // (Re)start the htlc timer if the invoice is still open. It can + var resolution acceptResolution + + // Auto-release the htlc if the invoice is still open. It can // only happen for mpp payments that there are htlcs in state // Accepted while the invoice is Open. if invoice.State == channeldb.ContractOpen { - err := i.startHtlcTimer( - rHash, circuitKey, - invoiceHtlc.AcceptTime, - ) - if err != nil { - return nil, err - } + resolution.acceptTime = invoiceHtlc.AcceptTime + resolution.autoRelease = true + } - i.hodlSubscribe(hodlChan, circuitKey) - return nil, nil + i.hodlSubscribe(hodlChan, ctx.circuitKey) + return &resolution, nil default: panic("unknown action")