ReactOS 0.4.15-dev-8127-g6338913
rbtree.h
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1/*
2 Red Black Trees
3 (C) 1999 Andrea Arcangeli <andrea@suse.de>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
19 linux/include/linux/rbtree.h
20
21 To use rbtrees you'll have to implement your own insert and search cores.
22 This will avoid us to use callbacks and to drop drammatically performances.
23 I know it's not the cleaner way, but in C (not in C++) to get
24 performances and genericity...
25
26 Some example of insert and search follows here. The search is a plain
27 normal search over an ordered tree. The insert instead must be implemented
28 int two steps: as first thing the code must insert the element in
29 order as a red leaf in the tree, then the support library function
30 rb_insert_color() must be called. Such function will do the
31 not trivial work to rebalance the rbtree if necessary.
32
33-----------------------------------------------------------------------
34static inline struct page * rb_search_page_cache(struct inode * inode,
35 unsigned long offset)
36{
37 struct rb_node * n = inode->i_rb_page_cache.rb_node;
38 struct page * page;
39
40 while (n)
41 {
42 page = rb_entry(n, struct page, rb_page_cache);
43
44 if (offset < page->offset)
45 n = n->rb_left;
46 else if (offset > page->offset)
47 n = n->rb_right;
48 else
49 return page;
50 }
51 return NULL;
52}
53
54static inline struct page * __rb_insert_page_cache(struct inode * inode,
55 unsigned long offset,
56 struct rb_node * node)
57{
58 struct rb_node ** p = &inode->i_rb_page_cache.rb_node;
59 struct rb_node * parent = NULL;
60 struct page * page;
61
62 while (*p)
63 {
64 parent = *p;
65 page = rb_entry(parent, struct page, rb_page_cache);
66
67 if (offset < page->offset)
68 p = &(*p)->rb_left;
69 else if (offset > page->offset)
70 p = &(*p)->rb_right;
71 else
72 return page;
73 }
74
75 rb_link_node(node, parent, p);
76
77 return NULL;
78}
79
80static inline struct page * rb_insert_page_cache(struct inode * inode,
81 unsigned long offset,
82 struct rb_node * node)
83{
84 struct page * ret;
85 if ((ret = __rb_insert_page_cache(inode, offset, node)))
86 goto out;
87 rb_insert_color(node, &inode->i_rb_page_cache);
88 out:
89 return ret;
90}
91-----------------------------------------------------------------------
92*/
93
94#ifndef _LINUX_RBTREE_H
95#define _LINUX_RBTREE_H
96
97struct rb_node
98{
100#define RB_RED 0
101#define RB_BLACK 1
104} __attribute__((aligned(sizeof(long))));
105/* The alignment might seem pointless, but allegedly CRIS needs it */
106
108{
111
112
113#define rb_parent(r) ((struct rb_node *)((r)->rb_parent_color & ~3))
114#define rb_color(r) ((r)->rb_parent_color & 1)
115#define rb_is_red(r) (!rb_color(r))
116#define rb_is_black(r) rb_color(r)
117#define rb_set_red(r) do { (r)->rb_parent_color &= ~1; } while (0)
118#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0)
119
120static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
121{
122 rb->rb_parent_color = (rb->rb_parent_color & 3) | (ULONG_PTR)p;
123}
124static inline void rb_set_color(struct rb_node *rb, ULONG_PTR color)
125{
126 rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
127}
128
129#define RB_ROOT (struct rb_root) { NULL, }
130#define rb_entry(ptr, type, member) container_of(ptr, type, member)
131
132#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
133#define RB_EMPTY_NODE(node) (rb_parent(node) != node)
134#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
135
136extern void rb_insert_color(struct rb_node *, struct rb_root *);
137extern void rb_erase(struct rb_node *, struct rb_root *);
138
139/* Find logical next and previous nodes in a tree */
140extern struct rb_node *rb_next(struct rb_node *);
141extern struct rb_node *rb_prev(struct rb_node *);
142extern struct rb_node *rb_first(struct rb_root *);
143extern struct rb_node *rb_last(struct rb_root *);
144
145/* Fast replacement of a single node without remove/rebalance/add/rebalance */
146extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
147 struct rb_root *root);
148
149static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
150 struct rb_node ** rb_link)
151{
152 node->rb_parent_color = (ULONG_PTR )parent;
153 node->rb_left = node->rb_right = NULL;
154
155 *rb_link = node;
156}
157
158extern void rb_insert(struct rb_root *root, struct rb_node *node,
159 int (*cmp)(struct rb_node *, struct rb_node *));
160
161#endif /* _LINUX_RBTREE_H */
#define NULL
Definition: types.h:112
r parent
Definition: btrfs.c:3010
struct rb_node * rb_last(struct rb_root *)
Definition: rbtree.c:307
static void rb_set_parent(struct rb_node *rb, struct rb_node *p)
Definition: rbtree.h:120
static void rb_link_node(struct rb_node *node, struct rb_node *parent, struct rb_node **rb_link)
Definition: rbtree.h:149
struct rb_node * rb_first(struct rb_root *)
Definition: rbtree.c:294
struct rb_node * rb_next(struct rb_node *)
Definition: rbtree.c:320
void rb_insert_color(struct rb_node *, struct rb_root *)
Definition: rbtree.c:71
void rb_erase(struct rb_node *, struct rb_root *)
Definition: rbtree.c:223
struct rb_root __attribute__
struct rb_node * rb_prev(struct rb_node *)
Definition: rbtree.c:346
void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root)
Definition: rbtree.c:368
static void rb_set_color(struct rb_node *rb, ULONG_PTR color)
Definition: rbtree.h:124
void rb_insert(struct rb_root *root, struct rb_node *node, int(*cmp)(struct rb_node *, struct rb_node *))
Definition: rbtree.c:392
#define ULONG_PTR
Definition: config.h:101
GLuint color
Definition: glext.h:6243
GLfloat GLfloat p
Definition: glext.h:8902
#define cmp(status, error)
Definition: error.c:114
Definition: rbtree.h:98
struct rb_node * rb_left
Definition: rbtree.h:103
ULONG_PTR rb_parent_color
Definition: rbtree.h:99
struct rb_node * rb_right
Definition: rbtree.h:102
struct rb_node * rb_node
Definition: rbtree.h:109
uint32_t ULONG_PTR
Definition: typedefs.h:65
Definition: dlist.c:348