1/* $NetBSD: rbtree.h,v 1.2 2012/02/17 08:20:55 yamt Exp $ */
2
3/*-
4 * Copyright (c) 2001 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas <matt@3am-software.com>.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _SYS_RBTREE_H_
33#define _SYS_RBTREE_H_
34
35#if defined(_KERNEL) || defined(_STANDALONE)
36#include <sys/types.h>
37#else
38#include <stdbool.h>
39#include <inttypes.h>
40#endif
41#include <sys/queue.h>
42#include <sys/endian.h>
43
44__BEGIN_DECLS
45
46typedef struct rb_node {
47 struct rb_node *rb_nodes[2];
48#define RB_DIR_LEFT 0
49#define RB_DIR_RIGHT 1
50#define RB_DIR_OTHER 1
51#define rb_left rb_nodes[RB_DIR_LEFT]
52#define rb_right rb_nodes[RB_DIR_RIGHT]
53
54 /*
55 * rb_info contains the two flags and the parent back pointer.
56 * We put the two flags in the low two bits since we know that
57 * rb_node will have an alignment of 4 or 8 bytes.
58 */
59 uintptr_t rb_info;
60#define RB_FLAG_POSITION 0x2
61#define RB_FLAG_RED 0x1
62#define RB_FLAG_MASK (RB_FLAG_POSITION|RB_FLAG_RED)
63#define RB_FATHER(rb) \
64 ((struct rb_node *)((rb)->rb_info & ~RB_FLAG_MASK))
65#define RB_SET_FATHER(rb, father) \
66 ((void)((rb)->rb_info = (uintptr_t)(father)|((rb)->rb_info & RB_FLAG_MASK)))
67
68#define RB_SENTINEL_P(rb) ((rb) == NULL)
69#define RB_LEFT_SENTINEL_P(rb) RB_SENTINEL_P((rb)->rb_left)
70#define RB_RIGHT_SENTINEL_P(rb) RB_SENTINEL_P((rb)->rb_right)
71#define RB_FATHER_SENTINEL_P(rb) RB_SENTINEL_P(RB_FATHER((rb)))
72#define RB_CHILDLESS_P(rb) \
73 (RB_SENTINEL_P(rb) || (RB_LEFT_SENTINEL_P(rb) && RB_RIGHT_SENTINEL_P(rb)))
74#define RB_TWOCHILDREN_P(rb) \
75 (!RB_SENTINEL_P(rb) && !RB_LEFT_SENTINEL_P(rb) && !RB_RIGHT_SENTINEL_P(rb))
76
77#define RB_POSITION(rb) \
78 (((rb)->rb_info & RB_FLAG_POSITION) ? RB_DIR_RIGHT : RB_DIR_LEFT)
79#define RB_RIGHT_P(rb) (RB_POSITION(rb) == RB_DIR_RIGHT)
80#define RB_LEFT_P(rb) (RB_POSITION(rb) == RB_DIR_LEFT)
81#define RB_RED_P(rb) (!RB_SENTINEL_P(rb) && ((rb)->rb_info & RB_FLAG_RED) != 0)
82#define RB_BLACK_P(rb) (RB_SENTINEL_P(rb) || ((rb)->rb_info & RB_FLAG_RED) == 0)
83#define RB_MARK_RED(rb) ((void)((rb)->rb_info |= RB_FLAG_RED))
84#define RB_MARK_BLACK(rb) ((void)((rb)->rb_info &= ~RB_FLAG_RED))
85#define RB_INVERT_COLOR(rb) ((void)((rb)->rb_info ^= RB_FLAG_RED))
86#define RB_ROOT_P(rbt, rb) ((rbt)->rbt_root == (rb))
87#define RB_SET_POSITION(rb, position) \
88 ((void)((position) ? ((rb)->rb_info |= RB_FLAG_POSITION) : \
89 ((rb)->rb_info &= ~RB_FLAG_POSITION)))
90#define RB_ZERO_PROPERTIES(rb) ((void)((rb)->rb_info &= ~RB_FLAG_MASK))
91#define RB_COPY_PROPERTIES(dst, src) \
92 ((void)((dst)->rb_info ^= ((dst)->rb_info ^ (src)->rb_info) & RB_FLAG_MASK))
93#define RB_SWAP_PROPERTIES(a, b) do { \
94 uintptr_t xorinfo = ((a)->rb_info ^ (b)->rb_info) & RB_FLAG_MASK; \
95 (a)->rb_info ^= xorinfo; \
96 (b)->rb_info ^= xorinfo; \
97 } while (/*CONSTCOND*/ 0)
98#ifdef RBDEBUG
99 TAILQ_ENTRY(rb_node) rb_link;
100#endif
101} rb_node_t;
102
103#define RB_TREE_MIN(T) rb_tree_iterate((T), NULL, RB_DIR_LEFT)
104#define RB_TREE_MAX(T) rb_tree_iterate((T), NULL, RB_DIR_RIGHT)
105#define RB_TREE_FOREACH(N, T) \
106 for ((N) = RB_TREE_MIN(T); (N); \
107 (N) = rb_tree_iterate((T), (N), RB_DIR_RIGHT))
108#define RB_TREE_FOREACH_REVERSE(N, T) \
109 for ((N) = RB_TREE_MAX(T); (N); \
110 (N) = rb_tree_iterate((T), (N), RB_DIR_LEFT))
111
112#ifdef RBDEBUG
113TAILQ_HEAD(rb_node_qh, rb_node);
114
115#define RB_TAILQ_REMOVE(a, b, c) TAILQ_REMOVE(a, b, c)
116#define RB_TAILQ_INIT(a) TAILQ_INIT(a)
117#define RB_TAILQ_INSERT_HEAD(a, b, c) TAILQ_INSERT_HEAD(a, b, c)
118#define RB_TAILQ_INSERT_BEFORE(a, b, c) TAILQ_INSERT_BEFORE(a, b, c)
119#define RB_TAILQ_INSERT_AFTER(a, b, c, d) TAILQ_INSERT_AFTER(a, b, c, d)
120#else
121#define RB_TAILQ_REMOVE(a, b, c) do { } while (/*CONSTCOND*/0)
122#define RB_TAILQ_INIT(a) do { } while (/*CONSTCOND*/0)
123#define RB_TAILQ_INSERT_HEAD(a, b, c) do { } while (/*CONSTCOND*/0)
124#define RB_TAILQ_INSERT_BEFORE(a, b, c) do { } while (/*CONSTCOND*/0)
125#define RB_TAILQ_INSERT_AFTER(a, b, c, d) do { } while (/*CONSTCOND*/0)
126#endif /* RBDEBUG */
127
128/*
129 * rbto_compare_nodes_fn:
130 * return a positive value if the first node > the second node.
131 * return a negative value if the first node < the second node.
132 * return 0 if they are considered same.
133 *
134 * rbto_compare_key_fn:
135 * return a positive value if the node > the key.
136 * return a negative value if the node < the key.
137 * return 0 if they are considered same.
138 */
139
140typedef signed int (*rbto_compare_nodes_fn)(void *, const void *, const void *);
141typedef signed int (*rbto_compare_key_fn)(void *, const void *, const void *);
142
143typedef struct {
144 rbto_compare_nodes_fn rbto_compare_nodes;
145 rbto_compare_key_fn rbto_compare_key;
146 size_t rbto_node_offset;
147 void *rbto_context;
148} rb_tree_ops_t;
149
150typedef struct rb_tree {
151 struct rb_node *rbt_root;
152 const rb_tree_ops_t *rbt_ops;
153 struct rb_node *rbt_minmax[2];
154#ifdef RBDEBUG
155 struct rb_node_qh rbt_nodes;
156#endif
157#ifdef RBSTATS
158 unsigned int rbt_count;
159 unsigned int rbt_insertions;
160 unsigned int rbt_removals;
161 unsigned int rbt_insertion_rebalance_calls;
162 unsigned int rbt_insertion_rebalance_passes;
163 unsigned int rbt_removal_rebalance_calls;
164 unsigned int rbt_removal_rebalance_passes;
165#endif
166} rb_tree_t;
167
168#ifdef RBSTATS
169#define RBSTAT_INC(v) ((void)((v)++))
170#define RBSTAT_DEC(v) ((void)((v)--))
171#else
172#define RBSTAT_INC(v) do { } while (/*CONSTCOND*/0)
173#define RBSTAT_DEC(v) do { } while (/*CONSTCOND*/0)
174#endif
175
176void rb_tree_init(rb_tree_t *, const rb_tree_ops_t *);
177void * rb_tree_insert_node(rb_tree_t *, void *);
178void * rb_tree_find_node(rb_tree_t *, const void *);
179void * rb_tree_find_node_geq(rb_tree_t *, const void *);
180void * rb_tree_find_node_leq(rb_tree_t *, const void *);
181void rb_tree_remove_node(rb_tree_t *, void *);
182void * rb_tree_iterate(rb_tree_t *, void *, const unsigned int);
183#ifdef RBDEBUG
184void rb_tree_check(const rb_tree_t *, bool);
185#endif
186#ifdef RBSTATS
187void rb_tree_depths(const rb_tree_t *, size_t *);
188#endif
189
190__END_DECLS
191
192#endif /* _SYS_RBTREE_H_*/
193