/* src/toolbox/avl.h - AVL tree implementation

   Copyright (C) 1996-2005, 2006, 2007, 2008
   CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO

   This file is part of CACAO.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.

*/


#ifndef _AVL_H
#define _AVL_H

#include "config.h"

#include "vm/types.h"

#include "threads/mutex.hpp"

#include "vm/global.h"


/* define direction in an AVL node ********************************************/

#define AVL_LEFT     0
#define AVL_RIGHT    1


/* tree comparator prototype **************************************************/

typedef s4 avl_comparator(const void *treenode, const void *node);


/* forward typedefs ***********************************************************/

typedef struct avl_tree_t avl_tree_t;
typedef struct avl_node_t avl_node_t;


/* avl_tree_t *****************************************************************/

struct avl_tree_t {
	Mutex*          mutex;              ///< Mutex to lock the tree.
	avl_node_t     *root;               /* pointer to root node               */
	avl_comparator *comparator;         /* pointer to comparison function     */
	s4              entries;            /* contains number of entries         */
};


/* avl_node_t *****************************************************************/

struct avl_node_t {
	void       *data;                   /* pointer to data structure          */
	s4          balance;                /* the range of the field is -2...2   */
	avl_node_t *childs[2];              /* pointers to the child nodes        */
};


/* function prototypes ********************************************************/

#ifdef __cplusplus
extern "C" {
#endif

avl_tree_t *avl_create(avl_comparator *comparator);
bool        avl_insert(avl_tree_t *tree, void *data);
void       *avl_find(avl_tree_t *tree, void *data);

#if !defined(NDEBUG)
void        avl_dump(avl_node_t* node, s4 indent);
#endif

#ifdef __cplusplus
} // extern "C"
#endif

#endif /* _AVL_H */


/*
 * These are local overrides for various environment variables in Emacs.
 * Please do not remove this and leave it at the end of the file, where
 * Emacs will automagically detect them.
 * ---------------------------------------------------------------------
 * Local variables:
 * mode: c
 * indent-tabs-mode: t
 * c-basic-offset: 4
 * tab-width: 4
 * End:
 */
