/** BEGIN COPYRIGHT BLOCK
 * Copyright (C) 2001 Sun Microsystems, Inc. Used by permission.
 * Copyright (C) 2005 Red Hat, Inc.
 * All rights reserved.
 *
 * License: GPL (version 3 or any later version).
 * See LICENSE for details. 
 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

/* avl.h - avl tree definitions */
/*
 * Copyright (c) 1993 Regents of the University of Michigan.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that this notice is preserved and that due credit is given
 * to the University of Michigan at Ann Arbor. The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission. This software
 * is provided ``as is'' without express or implied warranty.
 */


#ifndef _AVL
#define _AVL

/*
 * this structure represents a generic avl tree node.
 */

typedef struct avlnode {
	caddr_t		avl_data;
	signed char	avl_bf;
	struct avlnode	*avl_left;
	struct avlnode	*avl_right;
} Avlnode;

#if defined(__GNUC__) && (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 4)) || (__GNUC__ > 4))
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstrict-prototypes"
#endif

#ifndef _IFP
#define _IFP
typedef int (*IFP)(); /* takes undefined arguments */
#endif

#if defined(__GNUC__) && (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 4)) || (__GNUC__ > 4))
#pragma GCC diagnostic pop
#endif

#define NULLAVL	((Avlnode *) NULL)

/* balance factor values */
#define LH 	-1
#define EH 	0
#define RH 	1

/* avl routines */
#define avl_getone(x)	(x == 0 ? 0 : (x)->avl_data)
#define avl_onenode(x)	(x == 0 || ((x)->avl_left == 0 && (x)->avl_right == 0))
extern int avl_insert(Avlnode **root, void *data, IFP fcmp, IFP fdup);
extern caddr_t avl_delete(Avlnode **root, void *data, IFP fcmp );
extern caddr_t avl_find(Avlnode *root, void *data, IFP fcmp );
extern caddr_t avl_getfirst(Avlnode *root );
extern caddr_t avl_getnext(void);
extern int avl_dup_error(void);
extern int avl_apply(Avlnode *root, IFP fn, void *arg, int stopflag, int type);
extern int avl_free(Avlnode *root, IFP dfree);

/* apply traversal types */
#define AVL_PREORDER	1
#define AVL_INORDER	2
#define AVL_POSTORDER	3
/* what apply returns if it ran out of nodes */
#define AVL_NOMORE	-6

caddr_t avl_find_lin( Avlnode *root, caddr_t data, IFP fcmp );

#endif /* _AVL */