Method getSegment

src/jrd/replication/ChangeLog.cpp:1034–1089

}

ChangeLog::Segment* ChangeLog::getSegment(ULONG length)
{
	Segment* activeSegment = NULL;
	Segment* freeSegment = NULL;

	FB_UINT64 minSequence = MAX_UINT64;

	for (const auto segment : m_segments)
	{
		const auto segmentState = segment->getState();
		const auto segmentSequence = segment->getSequence();

		if (segmentState == SEGMENT_STATE_USED)
		{
			if (activeSegment)
				raiseError("Multiple active journal segments found");

			activeSegment = segment;
		}
		else if (segmentState == SEGMENT_STATE_FREE)
		{
			if (!freeSegment || segmentSequence < minSequence)
			{
				freeSegment = segment;
				minSequence = segmentSequence;
			}
		}
	}

	const auto state = m_sharedMemory->getHeader();

	if (activeSegment && activeSegment->hasData() && m_config->archiveTimeout)
	{
		const size_t deltaTimestamp = time(NULL) - state->timestamp;

		if (deltaTimestamp > m_config->archiveTimeout)
		{
			activeSegment->setState(SEGMENT_STATE_FULL);
			activeSegment = NULL;
			m_workingSemaphore.release();
		}
	}

	if (activeSegment)
		return activeSegment;

	if (freeSegment)
		return reuseSegment(freeSegment);

	// Allocate one more segment if configuration allows that

	if (!m_config->segmentCount || m_segments.getCount() < m_config->segmentCount)
		return createSegment();

	return NULL;
}