- Bug #1493322: bsddb: the __len__ method of a DB object has been fixed to

  return correct results.  It could previously incorrectly return 0 in some
  cases.  Fixes SF bug 1493322 (pybsddb bug 1184012).

1 files changed, 19 insertions, 3 deletions

diff --git a/Modules/_bsddb.c b/Modules/_bsddb.c
index 3684bfdce3..b3707e91b6 100644
--- a/Modules/_bsddb.c
+++ b/Modules/_bsddb.c
@@ -2450,10 +2450,15 @@ int DB_length(DBObject* self)
 
     if (self->haveStat) {  /* Has the stat function been called recently?  If
                               so, we can use the cached value. */
+#if (DBVER <= 32)
         flags = DB_CACHED_COUNTS;
+#else
+        flags = DB_FAST_STAT;
+#endif
     }
 
     MYDB_BEGIN_ALLOW_THREADS;
+redo_stat_for_length:
 #if (DBVER >= 43)
     err = self->db->stat(self->db, /*txnid*/ NULL, &sp, flags);
 #elif (DBVER >= 33)
@@ -2461,6 +2466,20 @@ int DB_length(DBObject* self)
 #else
     err = self->db->stat(self->db, &sp, NULL, flags);
 #endif
+
+    /* All the stat structures have matching fields upto the ndata field,
+       so we can use any of them for the type cast */
+    size = ((DB_BTREE_STAT*)sp)->bt_ndata;
+
+    /* A size of 0 could mean that BerkeleyDB no longer had the stat values cached.
+     * redo a full stat to make sure.
+     *   Fixes SF python bug 1493322, pybsddb bug 1184012
+     */
+    if (size == 0 && (flags & DB_FAST_STAT)) {
+        flags = 0;
+        goto redo_stat_for_length;
+    }
+
     MYDB_END_ALLOW_THREADS;
 
     if (err)
@@ -2468,9 +2487,6 @@ int DB_length(DBObject* self)
 
     self->haveStat = 1;
 
-    /* All the stat structures have matching fields upto the ndata field,
-       so we can use any of them for the type cast */
-    size = ((DB_BTREE_STAT*)sp)->bt_ndata;
     free(sp);
     return size;
 }