From 7141eab594ff8a362f2e4f3a8565eab699ce1f7e Mon Sep 17 00:00:00 2001
From: Christoph Klaffl <christoph@phreaker.eu>
Date: Wed, 30 Jan 2019 23:49:38 +0100
Subject: [PATCH] fix bookmark edge case where replication was already done to
 the latest snapshot (+ test)

---
 syncoid                                       |  5 ++
 .../4_bookmark_replication_edge_case/run.sh   | 46 +++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100755 tests/syncoid/4_bookmark_replication_edge_case/run.sh

diff --git a/syncoid b/syncoid
index 3f6f9ba..812c733 100755
--- a/syncoid
+++ b/syncoid
@@ -654,6 +654,11 @@ sub syncdataset {
 			# do a normal replication if bookmarks aren't used or if previous
 			# bookmark replication was only done to the next oldest snapshot
 			if (!$bookmark || $nextsnapshot) {
+				if ($matchingsnap eq $newsyncsnap) {
+					# edge case: bookmark replication used the latest snapshot
+					return 0;
+				}
+
 				my $sendcmd = "$sourcesudocmd $zfscmd send $sendoptions $args{'streamarg'} $sourcefsescaped\@$matchingsnapescaped $sourcefsescaped\@$newsyncsnapescaped";
 				my $recvcmd = "$targetsudocmd $zfscmd receive $recvoptions $receiveextraargs $forcedrecv $targetfsescaped";
 				my $pvsize = getsendsize($sourcehost,"$sourcefs\@$matchingsnap","$sourcefs\@$newsyncsnap",$sourceisroot);
diff --git a/tests/syncoid/4_bookmark_replication_edge_case/run.sh b/tests/syncoid/4_bookmark_replication_edge_case/run.sh
new file mode 100755
index 0000000..2a93ce4
--- /dev/null
+++ b/tests/syncoid/4_bookmark_replication_edge_case/run.sh
@@ -0,0 +1,46 @@
+#!/bin/bash
+
+# test replication edge cases with bookmarks
+
+set -x
+set -e
+
+. ../../common/lib.sh
+
+POOL_IMAGE="/tmp/syncoid-test-4.zpool"
+POOL_SIZE="200M"
+POOL_NAME="syncoid-test-4"
+TARGET_CHECKSUM="ad383b157b01635ddcf13612ac55577ad9c8dcf3fbfc9eb91792e27ec8db739b  -"
+
+truncate -s "${POOL_SIZE}" "${POOL_IMAGE}"
+
+zpool create -m none -f "${POOL_NAME}" "${POOL_IMAGE}"
+
+function cleanUp {
+  zpool export "${POOL_NAME}"
+}
+
+# export pool in any case
+trap cleanUp EXIT
+
+zfs create "${POOL_NAME}"/src
+zfs snapshot "${POOL_NAME}"/src@snap1
+zfs bookmark "${POOL_NAME}"/src@snap1 "${POOL_NAME}"/src#snap1
+# initial replication
+../../../syncoid --no-sync-snap --debug --compress=none "${POOL_NAME}"/src "${POOL_NAME}"/dst
+# destroy last common snapshot on source
+zfs destroy "${POOL_NAME}"/src@snap1
+zfs snapshot "${POOL_NAME}"/src@snap2
+
+# replicate which should fallback to bookmarks and stop because it's already on the latest snapshot
+../../../syncoid --no-sync-snap --debug --compress=none "${POOL_NAME}"/src "${POOL_NAME}"/dst || exit 1
+
+# verify
+output=$(zfs list -t snapshot -r -H -o name "${POOL_NAME}")
+checksum=$(echo "${output}" | grep -v syncoid_ | shasum -a 256)
+
+if [ "${checksum}" != "${TARGET_CHECKSUM}" ]; then
+	exit 1
+fi
+
+exit 0