tree.h revision 139824
165668Skris/*	$NetBSD: tree.h,v 1.8 2004/03/28 19:38:30 provos Exp $	*/
265668Skris/*	$OpenBSD: tree.h,v 1.7 2002/10/17 21:51:54 art Exp $	*/
365668Skris/* $FreeBSD: head/sys/sys/tree.h 139824 2005-01-07 02:28:28Z imp $ */
465668Skris
565668Skris/*-
665668Skris * Copyright 2002 Niels Provos <provos@citi.umich.edu>
765668Skris * All rights reserved.
865668Skris *
965668Skris * Redistribution and use in source and binary forms, with or without
1065668Skris * modification, are permitted provided that the following conditions
1165668Skris * are met:
1265668Skris * 1. Redistributions of source code must retain the above copyright
1365668Skris *    notice, this list of conditions and the following disclaimer.
1465668Skris * 2. Redistributions in binary form must reproduce the above copyright
1565668Skris *    notice, this list of conditions and the following disclaimer in the
1665668Skris *    documentation and/or other materials provided with the distribution.
1765668Skris *
1865668Skris * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
1965668Skris * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
2065668Skris * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
2165668Skris * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
2265668Skris * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
2365668Skris * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2460573Skris * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2560573Skris * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2660573Skris * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
2760573Skris * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2860573Skris */
2960573Skris
3060573Skris#ifndef	_SYS_TREE_H_
3160573Skris#define	_SYS_TREE_H_
3260573Skris
3365668Skris/*
3460573Skris * This file defines data structures for different types of trees:
3560573Skris * splay trees and red-black trees.
3660573Skris *
3760573Skris * A splay tree is a self-organizing data structure.  Every operation
3860573Skris * on the tree causes a splay to happen.  The splay moves the requested
3960573Skris * node to the root of the tree and partly rebalances it.
4060573Skris *
41 * This has the benefit that request locality causes faster lookups as
42 * the requested nodes move to the top of the tree.  On the other hand,
43 * every lookup causes memory writes.
44 *
45 * The Balance Theorem bounds the total access time for m operations
46 * and n inserts on an initially empty tree as O((m + n)lg n).  The
47 * amortized cost for a sequence of m accesses to a splay tree is O(lg n);
48 *
49 * A red-black tree is a binary search tree with the node color as an
50 * extra attribute.  It fulfills a set of conditions:
51 *	- every search path from the root to a leaf consists of the
52 *	  same number of black nodes,
53 *	- each red node (except for the root) has a black parent,
54 *	- each leaf node is black.
55 *
56 * Every operation on a red-black tree is bounded as O(lg n).
57 * The maximum height of a red-black tree is 2lg (n+1).
58 */
59
60#define SPLAY_HEAD(name, type)						\
61struct name {								\
62	struct type *sph_root; /* root of the tree */			\
63}
64
65#define SPLAY_INITIALIZER(root)						\
66	{ NULL }
67
68#define SPLAY_INIT(root) do {						\
69	(root)->sph_root = NULL;					\
70} while (/*CONSTCOND*/ 0)
71
72#define SPLAY_ENTRY(type)						\
73struct {								\
74	struct type *spe_left; /* left element */			\
75	struct type *spe_right; /* right element */			\
76}
77
78#define SPLAY_LEFT(elm, field)		(elm)->field.spe_left
79#define SPLAY_RIGHT(elm, field)		(elm)->field.spe_right
80#define SPLAY_ROOT(head)		(head)->sph_root
81#define SPLAY_EMPTY(head)		(SPLAY_ROOT(head) == NULL)
82
83/* SPLAY_ROTATE_{LEFT,RIGHT} expect that tmp hold SPLAY_{RIGHT,LEFT} */
84#define SPLAY_ROTATE_RIGHT(head, tmp, field) do {			\
85	SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(tmp, field);	\
86	SPLAY_RIGHT(tmp, field) = (head)->sph_root;			\
87	(head)->sph_root = tmp;						\
88} while (/*CONSTCOND*/ 0)
89
90#define SPLAY_ROTATE_LEFT(head, tmp, field) do {			\
91	SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(tmp, field);	\
92	SPLAY_LEFT(tmp, field) = (head)->sph_root;			\
93	(head)->sph_root = tmp;						\
94} while (/*CONSTCOND*/ 0)
95
96#define SPLAY_LINKLEFT(head, tmp, field) do {				\
97	SPLAY_LEFT(tmp, field) = (head)->sph_root;			\
98	tmp = (head)->sph_root;						\
99	(head)->sph_root = SPLAY_LEFT((head)->sph_root, field);		\
100} while (/*CONSTCOND*/ 0)
101
102#define SPLAY_LINKRIGHT(head, tmp, field) do {				\
103	SPLAY_RIGHT(tmp, field) = (head)->sph_root;			\
104	tmp = (head)->sph_root;						\
105	(head)->sph_root = SPLAY_RIGHT((head)->sph_root, field);	\
106} while (/*CONSTCOND*/ 0)
107
108#define SPLAY_ASSEMBLE(head, node, left, right, field) do {		\
109	SPLAY_RIGHT(left, field) = SPLAY_LEFT((head)->sph_root, field);	\
110	SPLAY_LEFT(right, field) = SPLAY_RIGHT((head)->sph_root, field);\
111	SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(node, field);	\
112	SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(node, field);	\
113} while (/*CONSTCOND*/ 0)
114
115/* Generates prototypes and inline functions */
116
117#define SPLAY_PROTOTYPE(name, type, field, cmp)				\
118void name##_SPLAY(struct name *, struct type *);			\
119void name##_SPLAY_MINMAX(struct name *, int);				\
120struct type *name##_SPLAY_INSERT(struct name *, struct type *);		\
121struct type *name##_SPLAY_REMOVE(struct name *, struct type *);		\
122									\
123/* Finds the node with the same key as elm */				\
124static __inline struct type *						\
125name##_SPLAY_FIND(struct name *head, struct type *elm)			\
126{									\
127	if (SPLAY_EMPTY(head))						\
128		return(NULL);						\
129	name##_SPLAY(head, elm);					\
130	if ((cmp)(elm, (head)->sph_root) == 0)				\
131		return (head->sph_root);				\
132	return (NULL);							\
133}									\
134									\
135static __inline struct type *						\
136name##_SPLAY_NEXT(struct name *head, struct type *elm)			\
137{									\
138	name##_SPLAY(head, elm);					\
139	if (SPLAY_RIGHT(elm, field) != NULL) {				\
140		elm = SPLAY_RIGHT(elm, field);				\
141		while (SPLAY_LEFT(elm, field) != NULL) {		\
142			elm = SPLAY_LEFT(elm, field);			\
143		}							\
144	} else								\
145		elm = NULL;						\
146	return (elm);							\
147}									\
148									\
149static __inline struct type *						\
150name##_SPLAY_MIN_MAX(struct name *head, int val)			\
151{									\
152	name##_SPLAY_MINMAX(head, val);					\
153        return (SPLAY_ROOT(head));					\
154}
155
156/* Main splay operation.
157 * Moves node close to the key of elm to top
158 */
159#define SPLAY_GENERATE(name, type, field, cmp)				\
160struct type *								\
161name##_SPLAY_INSERT(struct name *head, struct type *elm)		\
162{									\
163    if (SPLAY_EMPTY(head)) {						\
164	    SPLAY_LEFT(elm, field) = SPLAY_RIGHT(elm, field) = NULL;	\
165    } else {								\
166	    int __comp;							\
167	    name##_SPLAY(head, elm);					\
168	    __comp = (cmp)(elm, (head)->sph_root);			\
169	    if(__comp < 0) {						\
170		    SPLAY_LEFT(elm, field) = SPLAY_LEFT((head)->sph_root, field);\
171		    SPLAY_RIGHT(elm, field) = (head)->sph_root;		\
172		    SPLAY_LEFT((head)->sph_root, field) = NULL;		\
173	    } else if (__comp > 0) {					\
174		    SPLAY_RIGHT(elm, field) = SPLAY_RIGHT((head)->sph_root, field);\
175		    SPLAY_LEFT(elm, field) = (head)->sph_root;		\
176		    SPLAY_RIGHT((head)->sph_root, field) = NULL;	\
177	    } else							\
178		    return ((head)->sph_root);				\
179    }									\
180    (head)->sph_root = (elm);						\
181    return (NULL);							\
182}									\
183									\
184struct type *								\
185name##_SPLAY_REMOVE(struct name *head, struct type *elm)		\
186{									\
187	struct type *__tmp;						\
188	if (SPLAY_EMPTY(head))						\
189		return (NULL);						\
190	name##_SPLAY(head, elm);					\
191	if ((cmp)(elm, (head)->sph_root) == 0) {			\
192		if (SPLAY_LEFT((head)->sph_root, field) == NULL) {	\
193			(head)->sph_root = SPLAY_RIGHT((head)->sph_root, field);\
194		} else {						\
195			__tmp = SPLAY_RIGHT((head)->sph_root, field);	\
196			(head)->sph_root = SPLAY_LEFT((head)->sph_root, field);\
197			name##_SPLAY(head, elm);			\
198			SPLAY_RIGHT((head)->sph_root, field) = __tmp;	\
199		}							\
200		return (elm);						\
201	}								\
202	return (NULL);							\
203}									\
204									\
205void									\
206name##_SPLAY(struct name *head, struct type *elm)			\
207{									\
208	struct type __node, *__left, *__right, *__tmp;			\
209	int __comp;							\
210\
211	SPLAY_LEFT(&__node, field) = SPLAY_RIGHT(&__node, field) = NULL;\
212	__left = __right = &__node;					\
213\
214	while ((__comp = (cmp)(elm, (head)->sph_root)) != 0) {		\
215		if (__comp < 0) {					\
216			__tmp = SPLAY_LEFT((head)->sph_root, field);	\
217			if (__tmp == NULL)				\
218				break;					\
219			if ((cmp)(elm, __tmp) < 0){			\
220				SPLAY_ROTATE_RIGHT(head, __tmp, field);	\
221				if (SPLAY_LEFT((head)->sph_root, field) == NULL)\
222					break;				\
223			}						\
224			SPLAY_LINKLEFT(head, __right, field);		\
225		} else if (__comp > 0) {				\
226			__tmp = SPLAY_RIGHT((head)->sph_root, field);	\
227			if (__tmp == NULL)				\
228				break;					\
229			if ((cmp)(elm, __tmp) > 0){			\
230				SPLAY_ROTATE_LEFT(head, __tmp, field);	\
231				if (SPLAY_RIGHT((head)->sph_root, field) == NULL)\
232					break;				\
233			}						\
234			SPLAY_LINKRIGHT(head, __left, field);		\
235		}							\
236	}								\
237	SPLAY_ASSEMBLE(head, &__node, __left, __right, field);		\
238}									\
239									\
240/* Splay with either the minimum or the maximum element			\
241 * Used to find minimum or maximum element in tree.			\
242 */									\
243void name##_SPLAY_MINMAX(struct name *head, int __comp) \
244{									\
245	struct type __node, *__left, *__right, *__tmp;			\
246\
247	SPLAY_LEFT(&__node, field) = SPLAY_RIGHT(&__node, field) = NULL;\
248	__left = __right = &__node;					\
249\
250	while (1) {							\
251		if (__comp < 0) {					\
252			__tmp = SPLAY_LEFT((head)->sph_root, field);	\
253			if (__tmp == NULL)				\
254				break;					\
255			if (__comp < 0){				\
256				SPLAY_ROTATE_RIGHT(head, __tmp, field);	\
257				if (SPLAY_LEFT((head)->sph_root, field) == NULL)\
258					break;				\
259			}						\
260			SPLAY_LINKLEFT(head, __right, field);		\
261		} else if (__comp > 0) {				\
262			__tmp = SPLAY_RIGHT((head)->sph_root, field);	\
263			if (__tmp == NULL)				\
264				break;					\
265			if (__comp > 0) {				\
266				SPLAY_ROTATE_LEFT(head, __tmp, field);	\
267				if (SPLAY_RIGHT((head)->sph_root, field) == NULL)\
268					break;				\
269			}						\
270			SPLAY_LINKRIGHT(head, __left, field);		\
271		}							\
272	}								\
273	SPLAY_ASSEMBLE(head, &__node, __left, __right, field);		\
274}
275
276#define SPLAY_NEGINF	-1
277#define SPLAY_INF	1
278
279#define SPLAY_INSERT(name, x, y)	name##_SPLAY_INSERT(x, y)
280#define SPLAY_REMOVE(name, x, y)	name##_SPLAY_REMOVE(x, y)
281#define SPLAY_FIND(name, x, y)		name##_SPLAY_FIND(x, y)
282#define SPLAY_NEXT(name, x, y)		name##_SPLAY_NEXT(x, y)
283#define SPLAY_MIN(name, x)		(SPLAY_EMPTY(x) ? NULL	\
284					: name##_SPLAY_MIN_MAX(x, SPLAY_NEGINF))
285#define SPLAY_MAX(name, x)		(SPLAY_EMPTY(x) ? NULL	\
286					: name##_SPLAY_MIN_MAX(x, SPLAY_INF))
287
288#define SPLAY_FOREACH(x, name, head)					\
289	for ((x) = SPLAY_MIN(name, head);				\
290	     (x) != NULL;						\
291	     (x) = SPLAY_NEXT(name, head, x))
292
293/* Macros that define a red-black tree */
294#define RB_HEAD(name, type)						\
295struct name {								\
296	struct type *rbh_root; /* root of the tree */			\
297}
298
299#define RB_INITIALIZER(root)						\
300	{ NULL }
301
302#define RB_INIT(root) do {						\
303	(root)->rbh_root = NULL;					\
304} while (/*CONSTCOND*/ 0)
305
306#define RB_BLACK	0
307#define RB_RED		1
308#define RB_ENTRY(type)							\
309struct {								\
310	struct type *rbe_left;		/* left element */		\
311	struct type *rbe_right;		/* right element */		\
312	struct type *rbe_parent;	/* parent element */		\
313	int rbe_color;			/* node color */		\
314}
315
316#define RB_LEFT(elm, field)		(elm)->field.rbe_left
317#define RB_RIGHT(elm, field)		(elm)->field.rbe_right
318#define RB_PARENT(elm, field)		(elm)->field.rbe_parent
319#define RB_COLOR(elm, field)		(elm)->field.rbe_color
320#define RB_ROOT(head)			(head)->rbh_root
321#define RB_EMPTY(head)			(RB_ROOT(head) == NULL)
322
323#define RB_SET(elm, parent, field) do {					\
324	RB_PARENT(elm, field) = parent;					\
325	RB_LEFT(elm, field) = RB_RIGHT(elm, field) = NULL;		\
326	RB_COLOR(elm, field) = RB_RED;					\
327} while (/*CONSTCOND*/ 0)
328
329#define RB_SET_BLACKRED(black, red, field) do {				\
330	RB_COLOR(black, field) = RB_BLACK;				\
331	RB_COLOR(red, field) = RB_RED;					\
332} while (/*CONSTCOND*/ 0)
333
334#ifndef RB_AUGMENT
335#define RB_AUGMENT(x)
336#endif
337
338#define RB_ROTATE_LEFT(head, elm, tmp, field) do {			\
339	(tmp) = RB_RIGHT(elm, field);					\
340	if ((RB_RIGHT(elm, field) = RB_LEFT(tmp, field)) != NULL) {	\
341		RB_PARENT(RB_LEFT(tmp, field), field) = (elm);		\
342	}								\
343	RB_AUGMENT(elm);						\
344	if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {	\
345		if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))	\
346			RB_LEFT(RB_PARENT(elm, field), field) = (tmp);	\
347		else							\
348			RB_RIGHT(RB_PARENT(elm, field), field) = (tmp);	\
349	} else								\
350		(head)->rbh_root = (tmp);				\
351	RB_LEFT(tmp, field) = (elm);					\
352	RB_PARENT(elm, field) = (tmp);					\
353	RB_AUGMENT(tmp);						\
354	if ((RB_PARENT(tmp, field)))					\
355		RB_AUGMENT(RB_PARENT(tmp, field));			\
356} while (/*CONSTCOND*/ 0)
357
358#define RB_ROTATE_RIGHT(head, elm, tmp, field) do {			\
359	(tmp) = RB_LEFT(elm, field);					\
360	if ((RB_LEFT(elm, field) = RB_RIGHT(tmp, field)) != NULL) {	\
361		RB_PARENT(RB_RIGHT(tmp, field), field) = (elm);		\
362	}								\
363	RB_AUGMENT(elm);						\
364	if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {	\
365		if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))	\
366			RB_LEFT(RB_PARENT(elm, field), field) = (tmp);	\
367		else							\
368			RB_RIGHT(RB_PARENT(elm, field), field) = (tmp);	\
369	} else								\
370		(head)->rbh_root = (tmp);				\
371	RB_RIGHT(tmp, field) = (elm);					\
372	RB_PARENT(elm, field) = (tmp);					\
373	RB_AUGMENT(tmp);						\
374	if ((RB_PARENT(tmp, field)))					\
375		RB_AUGMENT(RB_PARENT(tmp, field));			\
376} while (/*CONSTCOND*/ 0)
377
378/* Generates prototypes and inline functions */
379#define RB_PROTOTYPE(name, type, field, cmp)				\
380void name##_RB_INSERT_COLOR(struct name *, struct type *);	\
381void name##_RB_REMOVE_COLOR(struct name *, struct type *, struct type *);\
382struct type *name##_RB_REMOVE(struct name *, struct type *);		\
383struct type *name##_RB_INSERT(struct name *, struct type *);		\
384struct type *name##_RB_FIND(struct name *, struct type *);		\
385struct type *name##_RB_NEXT(struct type *);				\
386struct type *name##_RB_MINMAX(struct name *, int);			\
387									\
388
389/* Main rb operation.
390 * Moves node close to the key of elm to top
391 */
392#define RB_GENERATE(name, type, field, cmp)				\
393void									\
394name##_RB_INSERT_COLOR(struct name *head, struct type *elm)		\
395{									\
396	struct type *parent, *gparent, *tmp;				\
397	while ((parent = RB_PARENT(elm, field)) != NULL &&		\
398	    RB_COLOR(parent, field) == RB_RED) {			\
399		gparent = RB_PARENT(parent, field);			\
400		if (parent == RB_LEFT(gparent, field)) {		\
401			tmp = RB_RIGHT(gparent, field);			\
402			if (tmp && RB_COLOR(tmp, field) == RB_RED) {	\
403				RB_COLOR(tmp, field) = RB_BLACK;	\
404				RB_SET_BLACKRED(parent, gparent, field);\
405				elm = gparent;				\
406				continue;				\
407			}						\
408			if (RB_RIGHT(parent, field) == elm) {		\
409				RB_ROTATE_LEFT(head, parent, tmp, field);\
410				tmp = parent;				\
411				parent = elm;				\
412				elm = tmp;				\
413			}						\
414			RB_SET_BLACKRED(parent, gparent, field);	\
415			RB_ROTATE_RIGHT(head, gparent, tmp, field);	\
416		} else {						\
417			tmp = RB_LEFT(gparent, field);			\
418			if (tmp && RB_COLOR(tmp, field) == RB_RED) {	\
419				RB_COLOR(tmp, field) = RB_BLACK;	\
420				RB_SET_BLACKRED(parent, gparent, field);\
421				elm = gparent;				\
422				continue;				\
423			}						\
424			if (RB_LEFT(parent, field) == elm) {		\
425				RB_ROTATE_RIGHT(head, parent, tmp, field);\
426				tmp = parent;				\
427				parent = elm;				\
428				elm = tmp;				\
429			}						\
430			RB_SET_BLACKRED(parent, gparent, field);	\
431			RB_ROTATE_LEFT(head, gparent, tmp, field);	\
432		}							\
433	}								\
434	RB_COLOR(head->rbh_root, field) = RB_BLACK;			\
435}									\
436									\
437void									\
438name##_RB_REMOVE_COLOR(struct name *head, struct type *parent, struct type *elm) \
439{									\
440	struct type *tmp;						\
441	while ((elm == NULL || RB_COLOR(elm, field) == RB_BLACK) &&	\
442	    elm != RB_ROOT(head)) {					\
443		if (RB_LEFT(parent, field) == elm) {			\
444			tmp = RB_RIGHT(parent, field);			\
445			if (RB_COLOR(tmp, field) == RB_RED) {		\
446				RB_SET_BLACKRED(tmp, parent, field);	\
447				RB_ROTATE_LEFT(head, parent, tmp, field);\
448				tmp = RB_RIGHT(parent, field);		\
449			}						\
450			if ((RB_LEFT(tmp, field) == NULL ||		\
451			    RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) &&\
452			    (RB_RIGHT(tmp, field) == NULL ||		\
453			    RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK)) {\
454				RB_COLOR(tmp, field) = RB_RED;		\
455				elm = parent;				\
456				parent = RB_PARENT(elm, field);		\
457			} else {					\
458				if (RB_RIGHT(tmp, field) == NULL ||	\
459				    RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK) {\
460					struct type *oleft;		\
461					if ((oleft = RB_LEFT(tmp, field)) \
462					    != NULL)			\
463						RB_COLOR(oleft, field) = RB_BLACK;\
464					RB_COLOR(tmp, field) = RB_RED;	\
465					RB_ROTATE_RIGHT(head, tmp, oleft, field);\
466					tmp = RB_RIGHT(parent, field);	\
467				}					\
468				RB_COLOR(tmp, field) = RB_COLOR(parent, field);\
469				RB_COLOR(parent, field) = RB_BLACK;	\
470				if (RB_RIGHT(tmp, field))		\
471					RB_COLOR(RB_RIGHT(tmp, field), field) = RB_BLACK;\
472				RB_ROTATE_LEFT(head, parent, tmp, field);\
473				elm = RB_ROOT(head);			\
474				break;					\
475			}						\
476		} else {						\
477			tmp = RB_LEFT(parent, field);			\
478			if (RB_COLOR(tmp, field) == RB_RED) {		\
479				RB_SET_BLACKRED(tmp, parent, field);	\
480				RB_ROTATE_RIGHT(head, parent, tmp, field);\
481				tmp = RB_LEFT(parent, field);		\
482			}						\
483			if ((RB_LEFT(tmp, field) == NULL ||		\
484			    RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) &&\
485			    (RB_RIGHT(tmp, field) == NULL ||		\
486			    RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK)) {\
487				RB_COLOR(tmp, field) = RB_RED;		\
488				elm = parent;				\
489				parent = RB_PARENT(elm, field);		\
490			} else {					\
491				if (RB_LEFT(tmp, field) == NULL ||	\
492				    RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) {\
493					struct type *oright;		\
494					if ((oright = RB_RIGHT(tmp, field)) \
495					    != NULL)			\
496						RB_COLOR(oright, field) = RB_BLACK;\
497					RB_COLOR(tmp, field) = RB_RED;	\
498					RB_ROTATE_LEFT(head, tmp, oright, field);\
499					tmp = RB_LEFT(parent, field);	\
500				}					\
501				RB_COLOR(tmp, field) = RB_COLOR(parent, field);\
502				RB_COLOR(parent, field) = RB_BLACK;	\
503				if (RB_LEFT(tmp, field))		\
504					RB_COLOR(RB_LEFT(tmp, field), field) = RB_BLACK;\
505				RB_ROTATE_RIGHT(head, parent, tmp, field);\
506				elm = RB_ROOT(head);			\
507				break;					\
508			}						\
509		}							\
510	}								\
511	if (elm)							\
512		RB_COLOR(elm, field) = RB_BLACK;			\
513}									\
514									\
515struct type *								\
516name##_RB_REMOVE(struct name *head, struct type *elm)			\
517{									\
518	struct type *child, *parent, *old = elm;			\
519	int color;							\
520	if (RB_LEFT(elm, field) == NULL)				\
521		child = RB_RIGHT(elm, field);				\
522	else if (RB_RIGHT(elm, field) == NULL)				\
523		child = RB_LEFT(elm, field);				\
524	else {								\
525		struct type *left;					\
526		elm = RB_RIGHT(elm, field);				\
527		while ((left = RB_LEFT(elm, field)) != NULL)		\
528			elm = left;					\
529		child = RB_RIGHT(elm, field);				\
530		parent = RB_PARENT(elm, field);				\
531		color = RB_COLOR(elm, field);				\
532		if (child)						\
533			RB_PARENT(child, field) = parent;		\
534		if (parent) {						\
535			if (RB_LEFT(parent, field) == elm)		\
536				RB_LEFT(parent, field) = child;		\
537			else						\
538				RB_RIGHT(parent, field) = child;	\
539			RB_AUGMENT(parent);				\
540		} else							\
541			RB_ROOT(head) = child;				\
542		if (RB_PARENT(elm, field) == old)			\
543			parent = elm;					\
544		(elm)->field = (old)->field;				\
545		if (RB_PARENT(old, field)) {				\
546			if (RB_LEFT(RB_PARENT(old, field), field) == old)\
547				RB_LEFT(RB_PARENT(old, field), field) = elm;\
548			else						\
549				RB_RIGHT(RB_PARENT(old, field), field) = elm;\
550			RB_AUGMENT(RB_PARENT(old, field));		\
551		} else							\
552			RB_ROOT(head) = elm;				\
553		RB_PARENT(RB_LEFT(old, field), field) = elm;		\
554		if (RB_RIGHT(old, field))				\
555			RB_PARENT(RB_RIGHT(old, field), field) = elm;	\
556		if (parent) {						\
557			left = parent;					\
558			do {						\
559				RB_AUGMENT(left);			\
560			} while ((left = RB_PARENT(left, field)) != NULL); \
561		}							\
562		goto color;						\
563	}								\
564	parent = RB_PARENT(elm, field);					\
565	color = RB_COLOR(elm, field);					\
566	if (child)							\
567		RB_PARENT(child, field) = parent;			\
568	if (parent) {							\
569		if (RB_LEFT(parent, field) == elm)			\
570			RB_LEFT(parent, field) = child;			\
571		else							\
572			RB_RIGHT(parent, field) = child;		\
573		RB_AUGMENT(parent);					\
574	} else								\
575		RB_ROOT(head) = child;					\
576color:									\
577	if (color == RB_BLACK)						\
578		name##_RB_REMOVE_COLOR(head, parent, child);		\
579	return (old);							\
580}									\
581									\
582/* Inserts a node into the RB tree */					\
583struct type *								\
584name##_RB_INSERT(struct name *head, struct type *elm)			\
585{									\
586	struct type *tmp;						\
587	struct type *parent = NULL;					\
588	int comp = 0;							\
589	tmp = RB_ROOT(head);						\
590	while (tmp) {							\
591		parent = tmp;						\
592		comp = (cmp)(elm, parent);				\
593		if (comp < 0)						\
594			tmp = RB_LEFT(tmp, field);			\
595		else if (comp > 0)					\
596			tmp = RB_RIGHT(tmp, field);			\
597		else							\
598			return (tmp);					\
599	}								\
600	RB_SET(elm, parent, field);					\
601	if (parent != NULL) {						\
602		if (comp < 0)						\
603			RB_LEFT(parent, field) = elm;			\
604		else							\
605			RB_RIGHT(parent, field) = elm;			\
606		RB_AUGMENT(parent);					\
607	} else								\
608		RB_ROOT(head) = elm;					\
609	name##_RB_INSERT_COLOR(head, elm);				\
610	return (NULL);							\
611}									\
612									\
613/* Finds the node with the same key as elm */				\
614struct type *								\
615name##_RB_FIND(struct name *head, struct type *elm)			\
616{									\
617	struct type *tmp = RB_ROOT(head);				\
618	int comp;							\
619	while (tmp) {							\
620		comp = cmp(elm, tmp);					\
621		if (comp < 0)						\
622			tmp = RB_LEFT(tmp, field);			\
623		else if (comp > 0)					\
624			tmp = RB_RIGHT(tmp, field);			\
625		else							\
626			return (tmp);					\
627	}								\
628	return (NULL);							\
629}									\
630									\
631/* ARGSUSED */								\
632struct type *								\
633name##_RB_NEXT(struct type *elm)					\
634{									\
635	if (RB_RIGHT(elm, field)) {					\
636		elm = RB_RIGHT(elm, field);				\
637		while (RB_LEFT(elm, field))				\
638			elm = RB_LEFT(elm, field);			\
639	} else {							\
640		if (RB_PARENT(elm, field) &&				\
641		    (elm == RB_LEFT(RB_PARENT(elm, field), field)))	\
642			elm = RB_PARENT(elm, field);			\
643		else {							\
644			while (RB_PARENT(elm, field) &&			\
645			    (elm == RB_RIGHT(RB_PARENT(elm, field), field)))\
646				elm = RB_PARENT(elm, field);		\
647			elm = RB_PARENT(elm, field);			\
648		}							\
649	}								\
650	return (elm);							\
651}									\
652									\
653struct type *								\
654name##_RB_MINMAX(struct name *head, int val)				\
655{									\
656	struct type *tmp = RB_ROOT(head);				\
657	struct type *parent = NULL;					\
658	while (tmp) {							\
659		parent = tmp;						\
660		if (val < 0)						\
661			tmp = RB_LEFT(tmp, field);			\
662		else							\
663			tmp = RB_RIGHT(tmp, field);			\
664	}								\
665	return (parent);						\
666}
667
668#define RB_NEGINF	-1
669#define RB_INF	1
670
671#define RB_INSERT(name, x, y)	name##_RB_INSERT(x, y)
672#define RB_REMOVE(name, x, y)	name##_RB_REMOVE(x, y)
673#define RB_FIND(name, x, y)	name##_RB_FIND(x, y)
674#define RB_NEXT(name, x, y)	name##_RB_NEXT(y)
675#define RB_MIN(name, x)		name##_RB_MINMAX(x, RB_NEGINF)
676#define RB_MAX(name, x)		name##_RB_MINMAX(x, RB_INF)
677
678#define RB_FOREACH(x, name, head)					\
679	for ((x) = RB_MIN(name, head);					\
680	     (x) != NULL;						\
681	     (x) = name##_RB_NEXT(x))
682
683#endif	/* _SYS_TREE_H_ */
684