1 /* $NetBSD: rbtree.h,v 1.8 2023/07/21 11:26:23 riastradh 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 46 typedef 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 (uintptr_t)0x2 61 #define RB_FLAG_RED (uintptr_t)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_NEXT(T, N) rb_tree_iterate((T), (N), RB_DIR_RIGHT) 106 #define RB_TREE_PREV(T, N) rb_tree_iterate((T), (N), RB_DIR_LEFT) 107 #define RB_TREE_FOREACH(N, T) \ 108 for ((N) = RB_TREE_MIN(T); (N); (N) = RB_TREE_NEXT((T), (N))) 109 #define RB_TREE_FOREACH_REVERSE(N, T) \ 110 for ((N) = RB_TREE_MAX(T); (N); (N) = RB_TREE_PREV((T), (N))) 111 #define RB_TREE_FOREACH_SAFE(N, T, S) \ 112 for ((N) = RB_TREE_MIN(T); \ 113 (N) && ((S) = RB_TREE_NEXT((T), (N)), 1); \ 114 (N) = (S)) 115 #define RB_TREE_FOREACH_REVERSE_SAFE(N, T, S) \ 116 for ((N) = RB_TREE_MAX(T); \ 117 (N) && ((S) = RB_TREE_PREV((T), (N)), 1); \ 118 (N) = (S)) 119 120 #ifdef RBDEBUG 121 TAILQ_HEAD(rb_node_qh, rb_node); 122 123 #define RB_TAILQ_REMOVE(a, b, c) TAILQ_REMOVE(a, b, c) 124 #define RB_TAILQ_INIT(a) TAILQ_INIT(a) 125 #define RB_TAILQ_INSERT_HEAD(a, b, c) TAILQ_INSERT_HEAD(a, b, c) 126 #define RB_TAILQ_INSERT_BEFORE(a, b, c) TAILQ_INSERT_BEFORE(a, b, c) 127 #define RB_TAILQ_INSERT_AFTER(a, b, c, d) TAILQ_INSERT_AFTER(a, b, c, d) 128 129 #define RBDEBUG_TREE_INITIALIZER(t) \ 130 .rbt_nodes = TAILQ_HEAD_INITIALIZER((t).rbt_nodes), 131 #else 132 #define RB_TAILQ_REMOVE(a, b, c) do { } while (/*CONSTCOND*/0) 133 #define RB_TAILQ_INIT(a) do { } while (/*CONSTCOND*/0) 134 #define RB_TAILQ_INSERT_HEAD(a, b, c) do { } while (/*CONSTCOND*/0) 135 #define RB_TAILQ_INSERT_BEFORE(a, b, c) do { } while (/*CONSTCOND*/0) 136 #define RB_TAILQ_INSERT_AFTER(a, b, c, d) do { } while (/*CONSTCOND*/0) 137 138 #define RBDEBUG_TREE_INITIALIZER(t) /* nothing */ 139 #endif /* RBDEBUG */ 140 141 /* 142 * rbto_compare_nodes_fn: 143 * return a positive value if the first node > the second node. 144 * return a negative value if the first node < the second node. 145 * return 0 if they are considered same. 146 * 147 * rbto_compare_key_fn: 148 * return a positive value if the node > the key. 149 * return a negative value if the node < the key. 150 * return 0 if they are considered same. 151 */ 152 153 typedef signed int (*rbto_compare_nodes_fn)(void *, const void *, const void *); 154 typedef signed int (*rbto_compare_key_fn)(void *, const void *, const void *); 155 156 typedef struct { 157 rbto_compare_nodes_fn rbto_compare_nodes; 158 rbto_compare_key_fn rbto_compare_key; 159 size_t rbto_node_offset; 160 void *rbto_context; 161 } rb_tree_ops_t; 162 163 typedef struct rb_tree { 164 struct rb_node *rbt_root; 165 const rb_tree_ops_t *rbt_ops; 166 struct rb_node *rbt_minmax[2]; 167 #ifdef RBDEBUG 168 struct rb_node_qh rbt_nodes; 169 #endif 170 #ifdef RBSTATS 171 unsigned int rbt_count; 172 unsigned int rbt_insertions; 173 unsigned int rbt_removals; 174 unsigned int rbt_insertion_rebalance_calls; 175 unsigned int rbt_insertion_rebalance_passes; 176 unsigned int rbt_removal_rebalance_calls; 177 unsigned int rbt_removal_rebalance_passes; 178 #endif 179 } rb_tree_t; 180 181 #ifdef RBSTATS 182 #define RBSTAT_INC(v) ((void)((v)++)) 183 #define RBSTAT_DEC(v) ((void)((v)--)) 184 #else 185 #define RBSTAT_INC(v) do { } while (/*CONSTCOND*/0) 186 #define RBSTAT_DEC(v) do { } while (/*CONSTCOND*/0) 187 #endif 188 189 #define RB_TREE_INIT_TYPECHECK(t) \ 190 0*sizeof(&(t) - (struct rb_tree *)0) 191 192 #define RB_TREE_INITIALIZER(t, ops) \ 193 { \ 194 .rbt_ops = (ops) + RB_TREE_INIT_TYPECHECK(t), \ 195 RBDEBUG_TREE_INITIALIZER(t) \ 196 } 197 198 void rb_tree_init(rb_tree_t *, const rb_tree_ops_t *); 199 void * rb_tree_insert_node(rb_tree_t *, void *); 200 void * rb_tree_find_node(rb_tree_t *, const void *); 201 void * rb_tree_find_node_geq(rb_tree_t *, const void *); 202 void * rb_tree_find_node_leq(rb_tree_t *, const void *); 203 void rb_tree_remove_node(rb_tree_t *, void *); 204 void * rb_tree_iterate(rb_tree_t *, void *, const unsigned int); 205 #ifdef RBDEBUG 206 void rb_tree_check(const rb_tree_t *, bool); 207 #endif 208 #ifdef RBSTATS 209 void rb_tree_depths(const rb_tree_t *, size_t *); 210 #endif 211 212 __END_DECLS 213 214 #endif /* _SYS_RBTREE_H_*/ 215