/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *	File:	ipc/ipc_splay.h
 *	Author:	Rich Draves
 *	Date:	1989
 *
 *	Declarations of primitive splay tree operations.
 */

#ifndef	_IPC_IPC_SPLAY_H_
#define _IPC_IPC_SPLAY_H_

#include <mach/port.h>
#include <kern/assert.h>
#include <kern/macro_help.h>
#include <ipc/ipc_entry.h>

typedef struct ipc_splay_tree {
	mach_port_t ist_name;		/* name used in last lookup */
	ipc_tree_entry_t ist_root;	/* root of middle tree */
	ipc_tree_entry_t ist_ltree;	/* root of left tree */
	ipc_tree_entry_t *ist_ltreep;	/* pointer into left tree */
	ipc_tree_entry_t ist_rtree;	/* root of right tree */
	ipc_tree_entry_t *ist_rtreep;	/* pointer into right tree */
} *ipc_splay_tree_t;

#define	ist_lock(splay)		/* no locking */
#define ist_unlock(splay)	/* no locking */

/* Initialize a raw splay tree */
extern void ipc_splay_tree_init(
	ipc_splay_tree_t	splay);

/* Pick a random entry in a splay tree */
extern boolean_t ipc_splay_tree_pick(
	ipc_splay_tree_t	splay,
	mach_port_t		*namep,
	ipc_tree_entry_t	*entryp);

/* Find an entry in a splay tree */
extern ipc_tree_entry_t ipc_splay_tree_lookup(
	ipc_splay_tree_t	splay,
	mach_port_t		name);

/* Insert a new entry into a splay tree */
extern void ipc_splay_tree_insert(
	ipc_splay_tree_t	splay,
	mach_port_t		name,
	ipc_tree_entry_t	entry);

/* Delete an entry from a splay tree */
extern void ipc_splay_tree_delete(
	ipc_splay_tree_t	splay,
	mach_port_t		name,
	ipc_tree_entry_t	entry);

/* Split a splay tree */
extern void ipc_splay_tree_split(
	ipc_splay_tree_t	splay,
	mach_port_t		name,
	ipc_splay_tree_t	entry);

/* Join two splay trees */
extern void ipc_splay_tree_join(
	ipc_splay_tree_t	splay,
	ipc_splay_tree_t	small);

/* Do a bounded splay tree lookup */
extern void ipc_splay_tree_bounds(
	ipc_splay_tree_t	splay,
	mach_port_t		name,
	mach_port_t		*lowerp, 
	mach_port_t		*upperp);

/* Initialize a symmetric order traversal of a splay tree */
extern ipc_tree_entry_t ipc_splay_traverse_start(
	ipc_splay_tree_t	splay);

/* Return the next entry in a symmetric order traversal of a splay tree */
extern ipc_tree_entry_t ipc_splay_traverse_next(
	ipc_splay_tree_t	splay,
	boolean_t		delete);

/* Terminate a symmetric order traversal of a splay tree */
extern void ipc_splay_traverse_finish(
	ipc_splay_tree_t	splay);

#endif	/* _IPC_IPC_SPLAY_H_ */