#45267 [Opn->Csd]: Revisit locking in DBA for DB4

ID: 45267 Updated by: sixd@php.net Reported By: sixd@php.net -Status: Open +Status: Closed Bug Type: DBM/DBA related Operating System: Linux PHP Version: 5.3CVS-2008-06-14 (CVS) New Comment: This bug has been fixed in CVS. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. Thank you for the report, and for helping us make PHP better. DBA with BDB 4 nows uses DBA's file locking so datafile corruption should no longer be possible. A side effect of re-introducing DBA-enforced locking is that "reading during write" (see tests/dba_db4.phpt) is not allowed. This is consistent with all other DBA drivers. Previous Comments: ------------------------------------------------------------------------ [2008-06-14 00:58:05] sixd@php.net Description: ------------ The locking for DBA with DB4 needs to be revisited. The way DB_INIT_LOCK and DB_FCNTL_LOCKING are passed to DB4, and the use of DBA_LOCK_EXT in dba.c seem to be based on the assumption that BDB will do locking. This isn't true with the way BDB is used by DBA. See http://bugs.php.net/bug.php?id=45266 for why DB_INIT_LOCK isn't valid. DB_FCNTL_LOCKING is undocumented. It implies that PHP does locking. It just tells BDB when to release file handles. Perhaps the easiest solution is for dba.c to use DBA_LOCK_ALL, but I'm not fully aware of the implications of this flag. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=45267&edit=1