toaruos/kernel/core/tree.c

/* vim: tabstop=4 shiftwidth=4 noexpandtab
 * 
 * General-purpose tree implementation
 */
#include <system.h>
#include <list.h>
#include <tree.h>

tree_t * tree_create() {
	tree_t * out = malloc(sizeof(tree_t));
	out->nodes  = 0;
	out->root   = NULL;
	return out;
}

void tree_set_root(tree_t * tree, void * value) {
	tree_node_t * root = tree_node_create(value);
	tree->root = root;
	tree->nodes = 1;
}

void tree_node_destroy(tree_node_t * node) {
	foreach(child, node->children) {
		tree_node_destroy((tree_node_t *)child->value);
	}
	free(node->value);
}

void tree_destroy(tree_t * tree) {
	if (tree->root) {
		tree_node_destroy(tree->root);
	}
}

void tree_node_free(tree_node_t * node) {
	if (!node) return;
	foreach(child, node->children) {
		tree_node_free(child->value);
	}
	free(node);
}

void tree_free(tree_t * tree) {
	tree_node_free(tree->root);
}

tree_node_t * tree_node_create(void * value) {
	tree_node_t * out = malloc(sizeof(tree_node_t));
	out->value = value;
	out->children = list_create();
	out->parent = NULL;
	return out;
}

void tree_node_insert_child_node(tree_t * tree, tree_node_t * parent, tree_node_t * node) {
	list_insert(parent->children, node);
	node->parent = parent;
	tree->nodes++;
}

tree_node_t * tree_node_insert_child(tree_t * tree, tree_node_t * parent, void * value) {
	tree_node_t * out = tree_node_create(value);
	tree_node_insert_child_node(tree, parent, out);
	return out;
}

tree_node_t * tree_node_find_parent(tree_node_t * haystack, tree_node_t * needle) {
	tree_node_t * found = NULL;
	foreach(child, haystack->children) {
		if (child->value == needle) {
			return haystack;
		}
		found = tree_node_find_parent((tree_node_t *)child->value, needle);
		if (found) {
			break;
		}
	}
	return found;
}

tree_node_t * tree_find_parent(tree_t * tree, tree_node_t * node) {
	if (!tree->root) return NULL;
	return tree_node_find_parent(tree->root, node);
}

void tree_node_parent_remove(tree_t * tree, tree_node_t * parent, tree_node_t * node) {
	tree->nodes--;
	list_delete(parent->children, list_find(parent->children, node));
	tree_node_free(node);
}

void tree_node_remove(tree_t * tree, tree_node_t * node) {
	tree_node_t * parent = node->parent;
	if (!parent) return;
	tree_node_parent_remove(tree, parent, node);
}