Maintain MDB_cursor.mc_top

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index e7564be8a0f662106d04d50e57040ec468ebbec0..2f671ed0a15da7406c9bd063eb0d557fdb3df159 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -5553,14 +5553,14 @@ fetchm:
        return rc;
 }
 
-/** Touch all the pages in the cursor stack.
+/** Touch all the pages in the cursor stack. Set mc_top.
  *     Makes sure all the pages are writable, before attempting a write operation.
  * @param[in] mc The cursor to operate on.
  */
 static int
 mdb_cursor_touch(MDB_cursor *mc)
 {
-       int rc;
+       int rc = MDB_SUCCESS;
 
        if (mc->mc_dbi > MAIN_DBI && !(*mc->mc_dbflag & DB_DIRTY)) {
                MDB_cursor mc2;
@@ -5571,13 +5571,14 @@ mdb_cursor_touch(MDB_cursor *mc)
                         return rc;
                *mc->mc_dbflag |= DB_DIRTY;
        }
-       for (mc->mc_top = 0; mc->mc_top < mc->mc_snum; mc->mc_top++) {
-               rc = mdb_page_touch(mc);
-               if (rc)
-                       return rc;
+       mc->mc_top = 0;
+       if (mc->mc_snum) {
+               do {
+                       rc = mdb_page_touch(mc);
+               } while (!rc && ++(mc->mc_top) < mc->mc_snum);
+               mc->mc_top = mc->mc_snum-1;
        }
-       mc->mc_top = mc->mc_snum-1;
-       return MDB_SUCCESS;
+       return rc;
 }
 
 /** Do not spill pages to disk if txn is getting full, may fail instead */
@@ -5640,6 +5641,7 @@ mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
        } else if (mc->mc_db->md_root == P_INVALID) {
                /* new database, cursor has nothing to point to */
                mc->mc_snum = 0;
+               mc->mc_top = 0;
                mc->mc_flags &= ~C_INITIALIZED;
                rc = MDB_NO_ROOT;
        } else {
@@ -6499,6 +6501,7 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node)
                memcpy(&mx->mx_db, NODEDATA(node), sizeof(MDB_db));
                mx->mx_cursor.mc_pg[0] = 0;
                mx->mx_cursor.mc_snum = 0;
+               mx->mx_cursor.mc_top = 0;
                mx->mx_cursor.mc_flags = C_SUB;
        } else {
                MDB_page *fp = NODEDATA(node);
@@ -6511,8 +6514,8 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node)
                mx->mx_db.md_entries = NUMKEYS(fp);
                COPY_PGNO(mx->mx_db.md_root, fp->mp_pgno);
                mx->mx_cursor.mc_snum = 1;
-               mx->mx_cursor.mc_flags = C_INITIALIZED|C_SUB;
                mx->mx_cursor.mc_top = 0;
+               mx->mx_cursor.mc_flags = C_INITIALIZED|C_SUB;
                mx->mx_cursor.mc_pg[0] = fp;
                mx->mx_cursor.mc_ki[0] = 0;
                if (mc->mc_db->md_flags & MDB_DUPFIXED) {