interval_tree.h revision 1.7.2.3 1 1.7.2.3 pgoyette /* $NetBSD: interval_tree.h,v 1.7.2.3 2019/01/18 08:50:56 pgoyette Exp $ */
2 1.7.2.2 pgoyette
3 1.7.2.2 pgoyette /*-
4 1.7.2.2 pgoyette * Copyright (c) 2018 The NetBSD Foundation, Inc.
5 1.7.2.2 pgoyette * All rights reserved.
6 1.7.2.2 pgoyette *
7 1.7.2.2 pgoyette * This code is derived from software contributed to The NetBSD Foundation
8 1.7.2.2 pgoyette * by Taylor R. Campbell.
9 1.7.2.2 pgoyette *
10 1.7.2.2 pgoyette * Redistribution and use in source and binary forms, with or without
11 1.7.2.2 pgoyette * modification, are permitted provided that the following conditions
12 1.7.2.2 pgoyette * are met:
13 1.7.2.2 pgoyette * 1. Redistributions of source code must retain the above copyright
14 1.7.2.2 pgoyette * notice, this list of conditions and the following disclaimer.
15 1.7.2.2 pgoyette * 2. Redistributions in binary form must reproduce the above copyright
16 1.7.2.2 pgoyette * notice, this list of conditions and the following disclaimer in the
17 1.7.2.2 pgoyette * documentation and/or other materials provided with the distribution.
18 1.7.2.2 pgoyette *
19 1.7.2.2 pgoyette * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 1.7.2.2 pgoyette * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 1.7.2.2 pgoyette * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 1.7.2.2 pgoyette * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 1.7.2.2 pgoyette * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 1.7.2.2 pgoyette * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 1.7.2.2 pgoyette * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 1.7.2.2 pgoyette * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 1.7.2.2 pgoyette * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 1.7.2.2 pgoyette * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 1.7.2.2 pgoyette * POSSIBILITY OF SUCH DAMAGE.
30 1.7.2.2 pgoyette */
31 1.7.2.2 pgoyette
32 1.7.2.2 pgoyette #ifndef _LINUX_INTERVAL_TREE_H_
33 1.7.2.2 pgoyette #define _LINUX_INTERVAL_TREE_H_
34 1.7.2.2 pgoyette
35 1.7.2.2 pgoyette #include <sys/rbtree.h>
36 1.7.2.2 pgoyette
37 1.7.2.2 pgoyette struct rb_root {
38 1.7.2.2 pgoyette struct rb_tree rbr_tree;
39 1.7.2.2 pgoyette };
40 1.7.2.2 pgoyette
41 1.7.2.2 pgoyette static inline bool
42 1.7.2.2 pgoyette RB_EMPTY_ROOT(struct rb_root *root)
43 1.7.2.2 pgoyette {
44 1.7.2.2 pgoyette
45 1.7.2.2 pgoyette return RB_TREE_MIN(&root->rbr_tree) == NULL;
46 1.7.2.2 pgoyette }
47 1.7.2.2 pgoyette
48 1.7.2.2 pgoyette struct interval_tree_node {
49 1.7.2.2 pgoyette struct rb_node itn_node;
50 1.7.2.2 pgoyette unsigned long start; /* inclusive */
51 1.7.2.2 pgoyette unsigned long last; /* inclusive */
52 1.7.2.2 pgoyette };
53 1.7.2.2 pgoyette
54 1.7.2.2 pgoyette static inline int
55 1.7.2.2 pgoyette interval_tree_compare_nodes(void *cookie, const void *va, const void *vb)
56 1.7.2.2 pgoyette {
57 1.7.2.2 pgoyette const struct interval_tree_node *na = va;
58 1.7.2.2 pgoyette const struct interval_tree_node *nb = vb;
59 1.7.2.2 pgoyette
60 1.7.2.2 pgoyette if (na->start < nb->start)
61 1.7.2.2 pgoyette return -1;
62 1.7.2.2 pgoyette if (na->start > nb->start)
63 1.7.2.2 pgoyette return +1;
64 1.7.2.2 pgoyette if (na->last < nb->last)
65 1.7.2.2 pgoyette return -1;
66 1.7.2.2 pgoyette if (na->last > nb->last)
67 1.7.2.2 pgoyette return +1;
68 1.7.2.2 pgoyette return 0;
69 1.7.2.2 pgoyette }
70 1.7.2.2 pgoyette
71 1.7.2.2 pgoyette static inline int
72 1.7.2.2 pgoyette interval_tree_compare_key(void *cookie, const void *vn, const void *vk)
73 1.7.2.2 pgoyette {
74 1.7.2.2 pgoyette const struct interval_tree_node *n = vn;
75 1.7.2.2 pgoyette const unsigned long *k = vk;
76 1.7.2.2 pgoyette
77 1.7.2.2 pgoyette if (n->start < *k)
78 1.7.2.2 pgoyette return -1;
79 1.7.2.2 pgoyette if (*k < n->start)
80 1.7.2.2 pgoyette return +1;
81 1.7.2.2 pgoyette return 0;
82 1.7.2.2 pgoyette }
83 1.7.2.2 pgoyette
84 1.7.2.2 pgoyette static const rb_tree_ops_t interval_tree_ops = {
85 1.7.2.2 pgoyette .rbto_compare_nodes = interval_tree_compare_nodes,
86 1.7.2.2 pgoyette .rbto_compare_key = interval_tree_compare_key,
87 1.7.2.2 pgoyette .rbto_node_offset = offsetof(struct interval_tree_node, itn_node),
88 1.7.2.2 pgoyette };
89 1.7.2.2 pgoyette
90 1.7.2.2 pgoyette static inline void
91 1.7.2.2 pgoyette interval_tree_init(struct rb_root *root)
92 1.7.2.2 pgoyette {
93 1.7.2.2 pgoyette
94 1.7.2.2 pgoyette rb_tree_init(&root->rbr_tree, &interval_tree_ops);
95 1.7.2.2 pgoyette }
96 1.7.2.2 pgoyette
97 1.7.2.2 pgoyette static inline void
98 1.7.2.2 pgoyette interval_tree_insert(struct interval_tree_node *node, struct rb_root *root)
99 1.7.2.2 pgoyette {
100 1.7.2.2 pgoyette struct interval_tree_node *collision __diagused;
101 1.7.2.2 pgoyette
102 1.7.2.2 pgoyette collision = rb_tree_insert_node(&root->rbr_tree, node);
103 1.7.2.2 pgoyette KASSERT(collision == node);
104 1.7.2.2 pgoyette }
105 1.7.2.2 pgoyette
106 1.7.2.2 pgoyette static inline void
107 1.7.2.2 pgoyette interval_tree_remove(struct interval_tree_node *node, struct rb_root *root)
108 1.7.2.2 pgoyette {
109 1.7.2.2 pgoyette
110 1.7.2.2 pgoyette rb_tree_remove_node(&root->rbr_tree, node);
111 1.7.2.2 pgoyette }
112 1.7.2.2 pgoyette
113 1.7.2.2 pgoyette static inline struct interval_tree_node *
114 1.7.2.2 pgoyette interval_tree_iter_first(struct rb_root *root, unsigned long start,
115 1.7.2.2 pgoyette unsigned long last)
116 1.7.2.2 pgoyette {
117 1.7.2.2 pgoyette struct interval_tree_node *node;
118 1.7.2.2 pgoyette
119 1.7.2.2 pgoyette node = rb_tree_find_node_geq(&root->rbr_tree, &start);
120 1.7.2.2 pgoyette if (node == NULL)
121 1.7.2.2 pgoyette return NULL;
122 1.7.2.2 pgoyette if (last < node->start)
123 1.7.2.2 pgoyette return NULL;
124 1.7.2.3 pgoyette KASSERT(node->start <= last && node->last >= start);
125 1.7.2.2 pgoyette
126 1.7.2.2 pgoyette return node;
127 1.7.2.2 pgoyette }
128 1.7.2.2 pgoyette
129 1.7.2.2 pgoyette /*
130 1.7.2.2 pgoyette * XXX Linux's interval_tree_iter_next doesn't take the root as an
131 1.7.2.2 pgoyette * argument, which makes this difficult. So we'll just patch those
132 1.7.2.2 pgoyette * uses.
133 1.7.2.2 pgoyette */
134 1.7.2.2 pgoyette static inline struct interval_tree_node *
135 1.7.2.2 pgoyette interval_tree_iter_next(struct rb_root *root, struct interval_tree_node *node,
136 1.7.2.2 pgoyette unsigned long start, unsigned long last)
137 1.7.2.2 pgoyette {
138 1.7.2.2 pgoyette struct interval_tree_node *next;
139 1.7.2.2 pgoyette
140 1.7.2.2 pgoyette KASSERT(node != NULL);
141 1.7.2.2 pgoyette next = rb_tree_iterate(&root->rbr_tree, node, RB_DIR_RIGHT);
142 1.7.2.2 pgoyette if (next == NULL)
143 1.7.2.2 pgoyette return NULL;
144 1.7.2.3 pgoyette if (last < next->start)
145 1.7.2.2 pgoyette return NULL;
146 1.7.2.3 pgoyette KASSERT(next->start <= last && next->last >= start);
147 1.7.2.2 pgoyette
148 1.7.2.2 pgoyette return next;
149 1.7.2.2 pgoyette }
150 1.7.2.2 pgoyette
151 1.7.2.2 pgoyette /*
152 1.7.2.2 pgoyette * XXX This is not actually postorder, but I can't fathom why you would
153 1.7.2.2 pgoyette * want postorder for an ordered tree; different insertion orders lead
154 1.7.2.2 pgoyette * to different traversal orders.
155 1.7.2.2 pgoyette */
156 1.7.2.2 pgoyette #define rbtree_postorder_for_each_entry_safe(NODE, TMP, ROOT, FIELD) \
157 1.7.2.2 pgoyette for ((NODE) = RB_TREE_MIN(&(ROOT)->rbr_tree); \
158 1.7.2.2 pgoyette ((NODE) != NULL && \
159 1.7.2.2 pgoyette ((TMP) = rb_tree_iterate(&(ROOT)->rbr_tree, (NODE), \
160 1.7.2.2 pgoyette RB_DIR_RIGHT))); \
161 1.7.2.2 pgoyette (NODE) = (TMP))
162 1.7.2.2 pgoyette
163 1.7.2.2 pgoyette #endif /* _LINUX_INTERVAL_TREE_H_ */
164