1 /* $NetBSD: rbtree.h,v 1.12 2024/05/12 10:34:56 rillig 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 #include <sys/types.h> 36 #include <sys/queue.h> 37 #include <sys/endian.h> 38 39 #if !defined(_KERNEL) && !defined(_STANDALONE) && defined(RBDEBUG) 40 #include <stdbool.h> 41 #endif 42 43 __BEGIN_DECLS 44 45 typedef struct rb_node { 46 struct rb_node *rb_nodes[2]; 47 #define RB_DIR_LEFT 0 48 #define RB_DIR_RIGHT 1 49 #define RB_DIR_OTHER 1 50 #define rb_left rb_nodes[RB_DIR_LEFT] 51 #define rb_right rb_nodes[RB_DIR_RIGHT] 52 53 /* 54 * rb_info contains the two flags and the parent back pointer. 55 * We put the two flags in the low two bits since we know that 56 * rb_node will have an alignment of 4 or 8 bytes. 57 */ 58 uintptr_t rb_info; 59 #define RB_FLAG_POSITION (uintptr_t)0x2 60 #define RB_FLAG_RED (uintptr_t)0x1 61 #define RB_FLAG_MASK (RB_FLAG_POSITION|RB_FLAG_RED) 62 #define RB_FATHER(rb) \ 63 ((struct rb_node *)((rb)->rb_info & ~RB_FLAG_MASK)) 64 #define RB_SET_FATHER(rb, father) \ 65 ((void)((rb)->rb_info = (uintptr_t)(father)|((rb)->rb_info & RB_FLAG_MASK))) 66 67 #define RB_SENTINEL_P(rb) ((rb) == NULL) 68 #define RB_LEFT_SENTINEL_P(rb) RB_SENTINEL_P((rb)->rb_left) 69 #define RB_RIGHT_SENTINEL_P(rb) RB_SENTINEL_P((rb)->rb_right) 70 #define RB_FATHER_SENTINEL_P(rb) RB_SENTINEL_P(RB_FATHER((rb))) 71 #define RB_CHILDLESS_P(rb) \ 72 (RB_SENTINEL_P(rb) || (RB_LEFT_SENTINEL_P(rb) && RB_RIGHT_SENTINEL_P(rb))) 73 #define RB_TWOCHILDREN_P(rb) \ 74 (!RB_SENTINEL_P(rb) && !RB_LEFT_SENTINEL_P(rb) && !RB_RIGHT_SENTINEL_P(rb)) 75 76 #define RB_POSITION(rb) \ 77 (((rb)->rb_info & RB_FLAG_POSITION) ? RB_DIR_RIGHT : RB_DIR_LEFT) 78 #define RB_RIGHT_P(rb) (RB_POSITION(rb) == RB_DIR_RIGHT) 79 #define RB_LEFT_P(rb) (RB_POSITION(rb) == RB_DIR_LEFT) 80 #define RB_RED_P(rb) (!RB_SENTINEL_P(rb) && ((rb)->rb_info & RB_FLAG_RED) != 0) 81 #define RB_BLACK_P(rb) (RB_SENTINEL_P(rb) || ((rb)->rb_info & RB_FLAG_RED) == 0) 82 #define RB_MARK_RED(rb) ((void)((rb)->rb_info |= RB_FLAG_RED)) 83 #define RB_MARK_BLACK(rb) ((void)((rb)->rb_info &= ~RB_FLAG_RED)) 84 #define RB_INVERT_COLOR(rb) ((void)((rb)->rb_info ^= RB_FLAG_RED)) 85 #define RB_ROOT_P(rbt, rb) ((rbt)->rbt_root == (rb)) 86 #define RB_SET_POSITION(rb, position) \ 87 ((void)((position) ? ((rb)->rb_info |= RB_FLAG_POSITION) : \ 88 ((rb)->rb_info &= ~RB_FLAG_POSITION))) 89 #define RB_ZERO_PROPERTIES(rb) ((void)((rb)->rb_info &= ~RB_FLAG_MASK)) 90 #define RB_COPY_PROPERTIES(dst, src) \ 91 ((void)((dst)->rb_info ^= ((dst)->rb_info ^ (src)->rb_info) & RB_FLAG_MASK)) 92 #define RB_SWAP_PROPERTIES(a, b) do { \ 93 uintptr_t xorinfo = ((a)->rb_info ^ (b)->rb_info) & RB_FLAG_MASK; \ 94 (a)->rb_info ^= xorinfo; \ 95 (b)->rb_info ^= xorinfo; \ 96 } while (0) 97 #ifdef RBDEBUG 98 TAILQ_ENTRY(rb_node) rb_link; 99 #endif 100 } rb_node_t; 101 102 #define RB_TREE_MIN(T) rb_tree_iterate((T), NULL, RB_DIR_LEFT) 103 #define RB_TREE_MAX(T) rb_tree_iterate((T), NULL, RB_DIR_RIGHT) 104 #define RB_TREE_NEXT(T, N) rb_tree_iterate((T), (N), RB_DIR_RIGHT) 105 #define RB_TREE_PREV(T, N) rb_tree_iterate((T), (N), RB_DIR_LEFT) 106 #define RB_TREE_FOREACH(N, T) \ 107 for ((N) = RB_TREE_MIN(T); (N); (N) = RB_TREE_NEXT((T), (N))) 108 #define RB_TREE_FOREACH_REVERSE(N, T) \ 109 for ((N) = RB_TREE_MAX(T); (N); (N) = RB_TREE_PREV((T), (N))) 110 #define RB_TREE_FOREACH_SAFE(N, T, S) \ 111 for ((N) = RB_TREE_MIN(T); \ 112 (N) && ((S) = RB_TREE_NEXT((T), (N)), 1); \ 113 (N) = (S)) 114 #define RB_TREE_FOREACH_REVERSE_SAFE(N, T, S) \ 115 for ((N) = RB_TREE_MAX(T); \ 116 (N) && ((S) = RB_TREE_PREV((T), (N)), 1); \ 117 (N) = (S)) 118 119 #ifdef RBDEBUG 120 TAILQ_HEAD(rb_node_qh, rb_node); 121 122 #define RB_TAILQ_REMOVE(a, b, c) TAILQ_REMOVE(a, b, c) 123 #define RB_TAILQ_INIT(a) TAILQ_INIT(a) 124 #define RB_TAILQ_INSERT_HEAD(a, b, c) TAILQ_INSERT_HEAD(a, b, c) 125 #define RB_TAILQ_INSERT_BEFORE(a, b, c) TAILQ_INSERT_BEFORE(a, b, c) 126 #define RB_TAILQ_INSERT_AFTER(a, b, c, d) TAILQ_INSERT_AFTER(a, b, c, d) 127 128 #define RBDEBUG_TREE_INITIALIZER(t) \ 129 .rbt_nodes = TAILQ_HEAD_INITIALIZER((t).rbt_nodes), 130 #else 131 #define RB_TAILQ_REMOVE(a, b, c) do { } while (0) 132 #define RB_TAILQ_INIT(a) do { } while (0) 133 #define RB_TAILQ_INSERT_HEAD(a, b, c) do { } while (0) 134 #define RB_TAILQ_INSERT_BEFORE(a, b, c) do { } while (0) 135 #define RB_TAILQ_INSERT_AFTER(a, b, c, d) do { } while (0) 136 137 #define RBDEBUG_TREE_INITIALIZER(t) /* nothing */ 138 #endif /* RBDEBUG */ 139 140 /* 141 * rbto_compare_nodes_fn: 142 * return a positive value if the first node > the second node. 143 * return a negative value if the first node < the second node. 144 * return 0 if they are considered same. 145 * 146 * rbto_compare_key_fn: 147 * return a positive value if the node > the key. 148 * return a negative value if the node < the key. 149 * return 0 if they are considered same. 150 */ 151 152 typedef signed int (*rbto_compare_nodes_fn)(void *, const void *, const void *); 153 typedef signed int (*rbto_compare_key_fn)(void *, const void *, const void *); 154 155 typedef struct { 156 rbto_compare_nodes_fn rbto_compare_nodes; 157 rbto_compare_key_fn rbto_compare_key; 158 size_t rbto_node_offset; 159 void *rbto_context; 160 } rb_tree_ops_t; 161 162 typedef struct rb_tree { 163 struct rb_node *rbt_root; 164 const rb_tree_ops_t *rbt_ops; 165 struct rb_node *rbt_minmax[2]; 166 #ifdef RBDEBUG 167 struct rb_node_qh rbt_nodes; 168 #endif 169 #ifdef RBSTATS 170 unsigned int rbt_count; 171 unsigned int rbt_insertions; 172 unsigned int rbt_removals; 173 unsigned int rbt_insertion_rebalance_calls; 174 unsigned int rbt_insertion_rebalance_passes; 175 unsigned int rbt_removal_rebalance_calls; 176 unsigned int rbt_removal_rebalance_passes; 177 #endif 178 } rb_tree_t; 179 180 #ifdef RBSTATS 181 #define RBSTAT_INC(v) ((void)((v)++)) 182 #define RBSTAT_DEC(v) ((void)((v)--)) 183 #else 184 #define RBSTAT_INC(v) do { } while (0) 185 #define RBSTAT_DEC(v) do { } while (0) 186 #endif 187 188 #define RB_TREE_INIT_TYPECHECK(t) \ 189 0*sizeof(&(t) - (struct rb_tree *)0) 190 191 #define RB_TREE_INITIALIZER(t, ops) \ 192 { \ 193 .rbt_ops = (ops) + RB_TREE_INIT_TYPECHECK(t), \ 194 RBDEBUG_TREE_INITIALIZER(t) \ 195 } 196 197 void rb_tree_init(rb_tree_t *, const rb_tree_ops_t *); 198 void * rb_tree_insert_node(rb_tree_t *, void *); 199 void * rb_tree_find_node(rb_tree_t *, const void *); 200 void * rb_tree_find_node_geq(rb_tree_t *, const void *); 201 void * rb_tree_find_node_leq(rb_tree_t *, const void *); 202 void rb_tree_remove_node(rb_tree_t *, void *); 203 void * rb_tree_iterate(rb_tree_t *, void *, const unsigned int); 204 #ifdef RBDEBUG 205 void rb_tree_check(const rb_tree_t *, bool); 206 #endif 207 #ifdef RBSTATS 208 void rb_tree_depths(const rb_tree_t *, size_t *); 209 #endif 210 211 __END_DECLS 212 213 #endif /* _SYS_RBTREE_H_*/ 214