1. If there are any Urgent tails, always send them first. (Don't rotate preference.)
2. If there are no other tails available, send a Dismissed tail. (Don't rotate preference.)
3. Otherwise, look for tails in your preferred priority, IMPORTANT or REQUESTING. If you have one, return it and rotate the preference.
4. If there's nothing in your preferred priority, look in the other priority. (Don't rotate preference.)
5. If there are no tails at all, return NULL. (Don't rotate preference.)

• STATE_IMPORTANT_FIRST (0) — means we're preferring our first IMPORTANT tail.
• STATE_REQUESTING (1) — means we're preferring a REQUESTING tail.
• STATE_IMPORTANT_SECOND (2) — means we're preferring our second IMPORTANT tail.

int get(TailQueue* tailQueue, Tail* result)
{
	if (isSetEmpty(tailQueue->m_queues[TAIL_URGENT]))
		return getNextInRotation(tailQueue, result);
	return dequeue(tailQueue, TAIL_URGENT, result);
}
int getNextInRotation(TailQueue* tailQueue, Tail* result)
{
	switch (tailQueue->m_state)
	{
		case STATE_IMPORTANT_FIRST:
			return getTailFromQueue(tailQueue, result,
					TAIL_IMPORTANT, TAIL_REQUESTING, STATE_REQUESTING);
		case STATE_REQUESTING:
			return getTailFromQueue(tailQueue, result, TAIL_REQUESTING,
					TAIL_IMPORTANT, STATE_IMPORTANT_SECOND);
		case STATE_IMPORTANT_SECOND:
		default:
			return getTailFromQueue(tailQueue, result, TAIL_IMPORTANT,
					TAIL_REQUESTING, STATE_IMPORTANT_FIRST);
	}
}

static int getTailFromQueue(TailQueue* tailQueue, Tail* result,
		int firstChoice, int secondChoice, int nextState)
{
	if (!isSetEmpty(tailQueue->m_queues[firstChoice]))
	{
		tailQueue->m_state = nextState;
		return dequeue(tailQueue, firstChoice, result);
	}
	if (!isSetEmpty(tailQueue->m_queues[secondChoice]))
		return dequeue(tailQueue, secondChoice, result);
	if (!isSetEmpty(tailQueue->m_queues[TAIL_DISMISSED]))
		return dequeue(tailQueue, TAIL_DISMISSED, result);
	return 0;
}
static int dequeue(TailQueue* tailQueue, int queueNumber, Tail* result)
{
	int found = getTailFromSet(tailQueue->m_queues[queueNumber], 0, result);
	if (found)
		removeTailFromSet(tailQueue->m_queues[queueNumber], *result);
	return found;
}