From 5acf2b126f4d2d2c4e07b2d160276f4729cbdcd2 Mon Sep 17 00:00:00 2001
From: Leonid Yuriev <leo@yuriev.ru>
Date: Fri, 19 Oct 2018 13:33:27 +0300
Subject: [PATCH] mdbx: backport - fix mdbx_dbi_sequence().

Change-Id: Ic620896ef42c1c2d85c07c146b72e773ab43a67d
---
 src/mdbx.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/mdbx.c b/src/mdbx.c
index 70dd069b..1751087a 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -12356,6 +12356,15 @@ int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
   if (unlikely(TXN_DBI_CHANGED(txn, dbi)))
     return MDBX_BAD_DBI;
 
+  if (unlikely(txn->mt_dbflags[dbi] & DB_STALE)) {
+    MDBX_cursor mc;
+    MDBX_xcursor mx;
+    /* Stale, must read the DB's root. cursor_init does it for us. */
+    int rc = mdbx_cursor_init(&mc, txn, dbi, &mx);
+    if (unlikely(rc != MDBX_SUCCESS))
+      return rc;
+  }
+
   MDBX_db *dbs = &txn->mt_dbs[dbi];
   if (likely(result))
     *result = dbs->md_seq;