ReactOS  0.4.13-dev-551-gf37fb1f
rbtree.h
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1 /*
2  Red Black Trees
3  (C) 1999 Andrea Arcangeli <andrea@suse.de>
4 
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 -----------------------------------------------------------------------
34 static 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 
54 static 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 
80 static 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 
97 struct rb_node
98 {
100 #define RB_RED 0
101 #define RB_BLACK 1
102  struct rb_node *rb_right;
103  struct rb_node *rb_left;
104 } __attribute__((aligned(sizeof(long))));
105 /* The alignment might seem pointless, but allegedly CRIS needs it */
106 
107 struct rb_root
108 {
109  struct rb_node *rb_node;
110 };
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 
120 static 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 }
124 static 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 
136 extern void rb_insert_color(struct rb_node *, struct rb_root *);
137 extern void rb_erase(struct rb_node *, struct rb_root *);
138 
139 /* Find logical next and previous nodes in a tree */
140 extern struct rb_node *rb_next(struct rb_node *);
141 extern struct rb_node *rb_prev(struct rb_node *);
142 extern struct rb_node *rb_first(struct rb_root *);
143 extern struct rb_node *rb_last(struct rb_root *);
144 
145 /* Fast replacement of a single node without remove/rebalance/add/rebalance */
146 extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
147  struct rb_root *root);
148 
149 static 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 
158 extern 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 */
static void rb_set_color(struct rb_node *rb, ULONG_PTR color)
Definition: rbtree.h:124
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_left
Definition: rbtree.h:103
struct rb_node * rb_next(struct rb_node *)
Definition: rbtree.c:320
void rb_insert(struct rb_root *root, struct rb_node *node, int(*cmp)(struct rb_node *, struct rb_node *))
Definition: rbtree.c:392
struct rb_node * rb_last(struct rb_root *)
Definition: rbtree.c:307
#define cmp(status, error)
Definition: error.c:114
struct rb_node * rb_prev(struct rb_node *)
Definition: rbtree.c:346
struct rb_node * rb_first(struct rb_root *)
Definition: rbtree.c:294
uint32_t ULONG_PTR
Definition: typedefs.h:63
struct node node
void rb_erase(struct rb_node *, struct rb_root *)
Definition: rbtree.c:223
void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root)
Definition: rbtree.c:368
GLuint color
Definition: glext.h:6243
struct rb_node * rb_node
Definition: rbtree.h:109
smooth NULL
Definition: ftsmooth.c:416
ULONG_PTR rb_parent_color
Definition: rbtree.h:99
r parent
Definition: btrfs.c:2708
struct rb_root __attribute__
static void rb_set_parent(struct rb_node *rb, struct rb_node *p)
Definition: rbtree.h:120
void rb_insert_color(struct rb_node *, struct rb_root *)
Definition: rbtree.c:71
Definition: rbtree.h:97
#define ULONG_PTR
Definition: config.h:101
GLfloat GLfloat p
Definition: glext.h:8902
Definition: dlist.c:348
struct rb_node * rb_right
Definition: rbtree.h:102