Function writeable

src/jrd/cch.cpp:4633–4666

#ifdef NOT_USED_OR_REPLACED
static inline bool writeable(BufferDesc* bdb)
{
/**************************************
 *
 *	w r i t e a b l e
 *
 **************************************
 *
 * Functional description
 *	See if a buffer is writeable.  A buffer is writeable if
 *	neither it nor any of it's higher precedence cousins are
 *	marked for write.
 *  This is the starting point of recursive walk of precedence
 *  graph. The writeable_mark member is used to mark already seen
 *  buffers to avoid repeated walk of the same sub-graph.
 *  Currently this function can't be called from more than one
 *  thread simultaneously. When SMP will be implemented we must
 *  take additional care about thread-safety.
 *
 **************************************/
	if (bdb->bdb_flags & BDB_marked)
		return false;

	if (QUE_EMPTY(bdb->bdb_higher))
		return true;

	BufferControl* bcb = bdb->bdb_bcb;

	Sync syncPrec(&bcb->bcb_syncPrecedence, "writeable");
	syncPrec.lock(SYNC_EXCLUSIVE);

	const ULONG mark = get_prec_walk_mark(bcb);
	return is_writeable(bdb, mark);
}


static bool is_writeable(BufferDesc* bdb, const ULONG mark)