Import wiredtiger: 5e6daf7d42727e3d86b2603c20852d1426dee55f from branch mongodb-4.4

ref: 5199f7f394..5e6daf7d42
for: 4.4.0-rc11

WT-6457       Restore static testing that zero-length row-store values are never written
WT-6464       Fix memory leak in __rollback_row_add_update

4 files changed, 20 insertions, 15 deletions

diff --git a/src/third_party/wiredtiger/import.data b/src/third_party/wiredtiger/import.data
index b8ecb80867b..6ba5f527c47 100644
--- a/src/third_party/wiredtiger/import.data
+++ b/src/third_party/wiredtiger/import.data
@@ -2,5 +2,5 @@
     "vendor": "wiredtiger",
     "github": "wiredtiger/wiredtiger.git",
     "branch": "mongodb-4.4",
-    "commit": "5199f7f394d6192475b83e211575be196afa1523"
+    "commit": "5e6daf7d42727e3d86b2603c20852d1426dee55f"
 }
diff --git a/src/third_party/wiredtiger/src/reconcile/rec_row.c b/src/third_party/wiredtiger/src/reconcile/rec_row.c
index dd072d57cf6..0bf79f2802a 100644
--- a/src/third_party/wiredtiger/src/reconcile/rec_row.c
+++ b/src/third_party/wiredtiger/src/reconcile/rec_row.c
@@ -770,11 +770,9 @@ __wt_rec_row_leaf(
 
         /*
          * If we reconcile an on disk key with a globally visible stop time point and there are no
-         * new updates for that key, skip writing that key. Don't do this additional cleanup work if
-         * a checkpoint is doing the work - we need that to be as streamlined as possible.
+         * new updates for that key, skip writing that key.
          */
-        if (upd == NULL && !F_ISSET(r, WT_REC_CHECKPOINT) &&
-          __wt_txn_tw_stop_visible_all(session, &tw))
+        if (upd == NULL && __wt_txn_tw_stop_visible_all(session, &tw))
             upd = &upd_tombstone;
 
         /* Build value cell. */
diff --git a/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c b/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c
index 9be945bb6c3..afc3508e577 100644
--- a/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c
+++ b/src/third_party/wiredtiger/src/txn/txn_rollback_to_stable.c
@@ -94,9 +94,10 @@ __rollback_row_add_update(WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip,
 {
     WT_DECL_RET;
     WT_PAGE_MODIFY *mod;
-    WT_UPDATE *old_upd, **upd_entry;
+    WT_UPDATE *last_upd, *old_upd, **upd_entry;
     size_t upd_size;
 
+    last_upd = NULL;
     /* If we don't yet have a modify structure, we'll need one. */
     WT_RET(__wt_page_modify_init(session, page));
     mod = page->modify;
@@ -108,9 +109,13 @@ __rollback_row_add_update(WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip,
     upd_entry = &mod->mod_row_update[WT_ROW_SLOT(page, rip)];
     upd_size = __wt_update_list_memsize(upd);
 
+    /* If there are existing updates, append them after the new updates. */
+    for (last_upd = upd; last_upd->next != NULL; last_upd = last_upd->next)
+        ;
+    last_upd->next = *upd_entry;
+
     /*
-     * If it's a full update list, we're trying to instantiate the row. Otherwise, it's just a
-     * single update that we'd like to append to the update list.
+     * We can either put a tombstone plus an update or a single update on the update chain.
      *
      * Set the "old" entry to the second update in the list so that the serialization function
      * succeeds in swapping the first update into place.
@@ -131,7 +136,12 @@ __rollback_row_add_update(WT_SESSION_IMPL *session, WT_PAGE *page, WT_ROW *rip,
      */
     WT_ERR(__wt_update_serial(session, NULL, page, upd_entry, &upd, upd_size, true));
 
+    if (0) {
 err:
+        if (last_upd != NULL)
+            last_upd->next = NULL;
+    }
+
     return (ret);
 }
 
diff --git a/src/third_party/wiredtiger/test/suite/test_empty_value.py b/src/third_party/wiredtiger/test/suite/test_empty_value.py
index d026b471277..b3db134a16f 100644
--- a/src/third_party/wiredtiger/test/suite/test_empty_value.py
+++ b/src/third_party/wiredtiger/test/suite/test_empty_value.py
@@ -26,10 +26,9 @@
 # ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 # OTHER DEALINGS IN THE SOFTWARE.
 #
-# test_dictionary.py
+# test_empty_value.py
 #       Smoke test empty row-store values.
 
-from wtdataset import simple_key
 from wiredtiger import stat
 import wiredtiger, wttest
 
@@ -39,22 +38,20 @@ class test_row_store_empty_values(wttest.WiredTigerTestCase):
 
     # Smoke test empty row-store values.
     def test_row_store_empty_values(self):
-        self.skipTest('empty row values are currently not working')
-
         nentries = 25000
         uri = 'file:test_empty_values'          # This is a btree layer test.
 
         # Create the object, open the cursor, insert some records with zero-length values.
-        self.session.create(uri, 'value_format=u,key_format=S')
+        self.session.create(uri, 'key_format=S,value_format=u')
         cursor = self.session.open_cursor(uri, None)
         for i in range(1, nentries + 1):
-            cursor[simple_key(cursor, i)] = ""
+            cursor[str(i)] = b''
         cursor.close()
 
         # Reopen to force the object to disk.
         self.reopen_conn()
 
-        # Confirm the values weren't stored..
+        # Confirm the values weren't stored.
         cursor = self.session.open_cursor('statistics:' + uri, None, 'statistics=(tree_walk)')
         self.assertEqual(cursor[stat.dsrc.btree_row_empty_values][2], nentries)