From b559811bf5e93f3200b68475bb748792acb5b5f9 Mon Sep 17 00:00:00 2001
From: Joost Jager <joost.jager@gmail.com>
Date: Wed, 13 May 2020 15:22:56 +0200
Subject: [PATCH] htlcswitch: extract updateCommitTxOrFail in link

Deduplicate code and prepare for further split of
handleDownstreamPkt.
---
 htlcswitch/link.go | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/htlcswitch/link.go b/htlcswitch/link.go
index 019ba0071..db7f15ff4 100644
--- a/htlcswitch/link.go
+++ b/htlcswitch/link.go
@@ -1097,9 +1097,7 @@ func (l *channelLink) htlcManager() {
 			// including all the currently pending entries. If the
 			// send was unsuccessful, then abandon the update,
 			// waiting for the revocation window to open up.
-			if err := l.updateCommitTx(); err != nil {
-				l.fail(LinkFailureError{code: ErrInternalError},
-					"unable to update commitment: %v", err)
+			if !l.updateCommitTxOrFail() {
 				return
 			}
 
@@ -1476,9 +1474,7 @@ func (l *channelLink) handleDownstreamPkt(pkt *htlcPacket) {
 	if l.channel.PendingLocalUpdateCount() >= uint64(l.cfg.BatchSize) ||
 		isSettle {
 
-		if err := l.updateCommitTx(); err != nil {
-			l.fail(LinkFailureError{code: ErrInternalError},
-				"unable to update commitment: %v", err)
+		if !l.updateCommitTxOrFail() {
 			return
 		}
 	}
@@ -1753,9 +1749,7 @@ func (l *channelLink) handleUpstreamMsg(msg lnwire.Message) {
 		// Otherwise, the remote party initiated the state transition,
 		// so we'll reply with a signature to provide them with their
 		// version of the latest commitment.
-		if err := l.updateCommitTx(); err != nil {
-			l.fail(LinkFailureError{code: ErrInternalError},
-				"unable to update commitment: %v", err)
+		if !l.updateCommitTxOrFail() {
 			return
 		}
 
@@ -1832,9 +1826,7 @@ func (l *channelLink) handleUpstreamMsg(msg lnwire.Message) {
 		// but there are still remote updates that are not in the remote
 		// commit tx yet, send out an update.
 		if l.channel.OweCommitment(true) {
-			if err := l.updateCommitTx(); err != nil {
-				l.fail(LinkFailureError{code: ErrInternalError},
-					"unable to update commitment: %v", err)
+			if !l.updateCommitTxOrFail() {
 				return
 			}
 		}
@@ -1918,6 +1910,18 @@ func (l *channelLink) ackDownStreamPackets() error {
 	return nil
 }
 
+// updateCommitTxOrFail updates the commitment tx and if that fails, it fails
+// the link.
+func (l *channelLink) updateCommitTxOrFail() bool {
+	if err := l.updateCommitTx(); err != nil {
+		l.fail(LinkFailureError{code: ErrInternalError},
+			"unable to update commitment: %v", err)
+		return false
+	}
+
+	return true
+}
+
 // updateCommitTx signs, then sends an update to the remote peer adding a new
 // commitment to their commitment chain which includes all the latest updates
 // we've received+processed up to this point.