1. Improvement CORE-4431 : Reduce contention for allocation table lock while database is in stalled physical backup state
2. Improvement CORE-4432 : Let attachments to not block others when allocation table is read first time
3. On Windows, file can not be deleted while system writes cached data into it, even if file is not open by anyone.
Therefore flush delta file implicitly before closing it.
- removed never used bcb_checkpoint and BDB_checkpoint
- removed conditional compilation for CACHE_WRITER as it is already ruled by flag BCB_cache_writer at almost all places
- added necessary checks for BCB_cache_writer when it was missed
1. Never allocate empty statement - always use att->prepare() to create statement interface
2. Separated IStatement into 2 parts - statement itself and resultset.
3. Added stmt->openCursor() (and att->openCursor() for unprepared statements) to create IResultSet.
4. Always use IMessageMetadata (former IParametersMetadata) to pass message fromat info from client,
therefore avoiding need in BLR generation in client applications.
Fixed assertion in CCH_exclusive_attachment
Rolled back my changes required to let cancelOperation() enter engine after shutdown
Better locks' history in SyncObject
1. Frontported fix for CORE-3935 and CORE-3993.
2. Added debugging support for mutexes and rwlocks in Vulcan style.
Unfortunately after last 'svn up' build asserts in JrdStatement:71.
2) Reworked the lock manager synchronization: added the RAII mutex holders and avoided dirty reads for the shared memory.
3) Encapsulated lck_length into the Lock class + small related refactoring.
4) Front ported recent fixes from the v2.x branches.
5) Misc cleanup.
Also some cleanups, the most important are:
- meaningful ctor on Jrd::Lock, helping to avoid code dup
- avoid unneeded h-file dependencies, making boot build engine dependent
