Method _removePage

src/common/classes/tree.h:887–988

template <typename Value, typename Key, typename KeyOfValue, typename Cmp>
void BePlusTree<Value, Key, KeyOfValue, Cmp>::_removePage(const int nodeLevel, NodePtr node)
{
	NodeList *list;
	// Get parent and adjust the links
	if (nodeLevel)
	{
		NodeList *temp = node.nodes;
		if (temp->prev)
			temp->prev->next = temp->next;
		if (temp->next)
			temp->next->prev = temp->prev;
		list = temp->parent;
	}
	else
	{
		ItemList *temp = node.items;
		if (temp->prev)
			temp->prev->next = temp->next;
		if (temp->next)
			temp->next->prev = temp->prev;
		list = temp->parent;
	}

	if (list->getCount() == 1)
	{
		// Only one node left in the list. We cannot remove it directly
		// because is would invalidate our tree structure
		NodeList *temp;
		if ((temp = list->prev) && NEED_MERGE(temp->getCount(), NODE_COUNT)) {
			_removePage(nodeLevel + 1, list);
		}
		else
		if ((temp = list->next) && NEED_MERGE(temp->getCount(), NODE_COUNT)) {
			_removePage(nodeLevel + 1, list);
		}
		else
		if ((temp = list->prev))
		{
			NodeList::setNodeParent(((*list)[0] = (*temp)[temp->getCount() - 1]), nodeLevel, list);
			temp->shrink(temp->getCount() - 1);
		}
		else
		if ((temp = list->next))
		{
			NodeList::setNodeParent(((*list)[0] = (*temp)[0]), nodeLevel, list);
			temp->remove(0);
		}
		else
		{
			// It means the tree is broken
			fb_assert(false);
		}
	}
	else
	{
		FB_SIZE_T pos;
#ifndef DEV_BUILD
		list->find(NodeList::generate(list, node), pos);