node_tree.c

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#include "fitz-base.h"
#include "fitz-world.h"

fz_error *
fz_newtree(fz_tree **treep)
{
	fz_tree *tree;

	tree = *treep = fz_malloc(sizeof (fz_tree));
	if (!tree)
		return fz_outofmem;

	tree->refs = 1;
	tree->root = nil;
	tree->head = nil;

	return fz_okay;
}

fz_tree *
fz_keeptree(fz_tree *tree)
{
	tree->refs ++;
	return tree;
}

void
fz_droptree(fz_tree *tree)
{
	if (--tree->refs == 0)
	{
		if (tree->root)
			fz_dropnode(tree->root);
		fz_free(tree);
	}
}

fz_rect
fz_boundtree(fz_tree *tree, fz_matrix ctm)
{
	if (tree->root)
		return fz_boundnode(tree->root, ctm);
	return fz_emptyrect;
}

void
fz_insertnodefirst(fz_node *parent, fz_node *child)
{
	child->parent = parent;
	child->next = parent->first;
	parent->first = child;
	if (!parent->last)
		parent->last = child;
}

void
fz_insertnodelast(fz_node *parent, fz_node *child)
{
	child->parent = parent;
	if (!parent->first)
		parent->first = child;
	else
		parent->last->next = child;
	parent->last = child;
}

void
fz_insertnodeafter(fz_node *prev, fz_node *child)
{
	fz_node *parent = prev->parent;
	child->parent = parent;
	if (parent->last == prev)
		parent->last = child;
	child->next = prev->next;
	prev->next = child;
}

void
fz_removenode(fz_node *child)
{
	fz_node *parent = child->parent;
	fz_node *prev;
	fz_node *node;

	if (parent->first == child)
	{
		parent->first = child->next;
		if (parent->last == child)
			parent->last = nil;
		return;
	}

	prev = parent->first;
	node = prev->next;

	while (node)
	{
		if (node == child)
		{
			prev->next = child->next;
		}
		prev = node;
		node = node->next;
	}

	parent->last = prev;
}