]>
Commit | Line | Data |
---|---|---|
7ba890bf KP |
1 | /* |
2 | Red Black Trees | |
3 | (C) 1999 Andrea Arcangeli <andrea@suse.de> | |
9dd228b5 | 4 | |
1a459660 | 5 | * SPDX-License-Identifier: GPL-2.0+ |
7ba890bf KP |
6 | |
7 | linux/include/linux/rbtree.h | |
8 | ||
9 | To use rbtrees you'll have to implement your own insert and search cores. | |
10 | This will avoid us to use callbacks and to drop drammatically performances. | |
11 | I know it's not the cleaner way, but in C (not in C++) to get | |
12 | performances and genericity... | |
13 | ||
9dd228b5 | 14 | See Documentation/rbtree.txt for documentation and samples. |
7ba890bf KP |
15 | */ |
16 | ||
17 | #ifndef _LINUX_RBTREE_H | |
18 | #define _LINUX_RBTREE_H | |
19 | ||
9dd228b5 HS |
20 | #ifndef __UBOOT__ |
21 | #include <linux/kernel.h> | |
22 | #endif | |
7ba890bf KP |
23 | #include <linux/stddef.h> |
24 | ||
9dd228b5 HS |
25 | struct rb_node { |
26 | unsigned long __rb_parent_color; | |
7ba890bf KP |
27 | struct rb_node *rb_right; |
28 | struct rb_node *rb_left; | |
29 | } __attribute__((aligned(sizeof(long)))); | |
30 | /* The alignment might seem pointless, but allegedly CRIS needs it */ | |
31 | ||
9dd228b5 | 32 | struct rb_root { |
7ba890bf KP |
33 | struct rb_node *rb_node; |
34 | }; | |
35 | ||
36 | ||
9dd228b5 | 37 | #define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3)) |
7ba890bf KP |
38 | |
39 | #define RB_ROOT (struct rb_root) { NULL, } | |
40 | #define rb_entry(ptr, type, member) container_of(ptr, type, member) | |
41 | ||
9dd228b5 HS |
42 | #define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL) |
43 | ||
44 | /* 'empty' nodes are nodes that are known not to be inserted in an rbree */ | |
45 | #define RB_EMPTY_NODE(node) \ | |
46 | ((node)->__rb_parent_color == (unsigned long)(node)) | |
47 | #define RB_CLEAR_NODE(node) \ | |
48 | ((node)->__rb_parent_color = (unsigned long)(node)) | |
49 | ||
7ba890bf KP |
50 | |
51 | extern void rb_insert_color(struct rb_node *, struct rb_root *); | |
52 | extern void rb_erase(struct rb_node *, struct rb_root *); | |
53 | ||
9dd228b5 | 54 | |
7ba890bf | 55 | /* Find logical next and previous nodes in a tree */ |
9dd228b5 HS |
56 | extern struct rb_node *rb_next(const struct rb_node *); |
57 | extern struct rb_node *rb_prev(const struct rb_node *); | |
58 | extern struct rb_node *rb_first(const struct rb_root *); | |
59 | extern struct rb_node *rb_last(const struct rb_root *); | |
60 | ||
61 | /* Postorder iteration - always visit the parent after its children */ | |
62 | extern struct rb_node *rb_first_postorder(const struct rb_root *); | |
63 | extern struct rb_node *rb_next_postorder(const struct rb_node *); | |
7ba890bf KP |
64 | |
65 | /* Fast replacement of a single node without remove/rebalance/add/rebalance */ | |
9dd228b5 | 66 | extern void rb_replace_node(struct rb_node *victim, struct rb_node *new, |
7ba890bf KP |
67 | struct rb_root *root); |
68 | ||
69 | static inline void rb_link_node(struct rb_node * node, struct rb_node * parent, | |
70 | struct rb_node ** rb_link) | |
71 | { | |
9dd228b5 | 72 | node->__rb_parent_color = (unsigned long)parent; |
7ba890bf KP |
73 | node->rb_left = node->rb_right = NULL; |
74 | ||
75 | *rb_link = node; | |
76 | } | |
77 | ||
9dd228b5 HS |
78 | #define rb_entry_safe(ptr, type, member) \ |
79 | ({ typeof(ptr) ____ptr = (ptr); \ | |
80 | ____ptr ? rb_entry(____ptr, type, member) : NULL; \ | |
81 | }) | |
82 | ||
83 | /** | |
84 | * rbtree_postorder_for_each_entry_safe - iterate over rb_root in post order of | |
85 | * given type safe against removal of rb_node entry | |
86 | * | |
87 | * @pos: the 'type *' to use as a loop cursor. | |
88 | * @n: another 'type *' to use as temporary storage | |
89 | * @root: 'rb_root *' of the rbtree. | |
90 | * @field: the name of the rb_node field within 'type'. | |
91 | */ | |
92 | #define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \ | |
93 | for (pos = rb_entry_safe(rb_first_postorder(root), typeof(*pos), field); \ | |
94 | pos && ({ n = rb_entry_safe(rb_next_postorder(&pos->field), \ | |
95 | typeof(*pos), field); 1; }); \ | |
96 | pos = n) | |
97 | ||
7ba890bf | 98 | #endif /* _LINUX_RBTREE_H */ |