Method init

src/jrd/extds/ExtDS.cpp:2590–2624

//  EngineCallbackGuard

void EngineCallbackGuard::init(thread_db* tdbb, Connection& conn, const char* from)
{
	m_tdbb = tdbb;
	m_mutex = &conn.m_mutex;
	m_saveConnection = NULL;

	if (m_tdbb && m_tdbb->getDatabase())
	{
		jrd_tra* transaction = m_tdbb->getTransaction();
		if (transaction)
		{
			if (transaction->tra_callback_count >= MAX_CALLBACKS)
				ERR_post(Arg::Gds(isc_exec_sql_max_call_exceeded));

			transaction->tra_callback_count++;
		}

		Jrd::Attachment* attachment = m_tdbb->getAttachment();
		if (attachment)
		{
			m_saveConnection = attachment->att_ext_connection;
			m_stable = attachment->getStable();
			m_stable->getSync()->leave();

			Jrd::AttSyncLockGuard guardAsync(*m_stable->getSync(true, true), FB_FUNCTION);
			Jrd::AttSyncLockGuard guardMain(*m_stable->getSync(), FB_FUNCTION);
			if (m_stable->getHandle() == attachment)
				attachment->att_ext_connection = &conn;
		}
	}

	if (m_mutex) {
		m_mutex->enter(from);
	}
}

EngineCallbackGuard::~EngineCallbackGuard()
{