rbtree.c (1975e59375756da4ff4e6e7d12f67485e813ace0) rbtree.c (55a981027fc393c86de2c4e7836c9515088a9a58)
1/*
2 Red Black Trees
3 (C) 1999 Andrea Arcangeli <andrea@suse.de>
4 (C) 2002 David Woodhouse <dwmw2@infradead.org>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or

--- 12 unchanged lines hidden (view full) ---

21*/
22
23#include <linux/rbtree.h>
24#include <linux/module.h>
25
26static void __rb_rotate_left(struct rb_node *node, struct rb_root *root)
27{
28 struct rb_node *right = node->rb_right;
1/*
2 Red Black Trees
3 (C) 1999 Andrea Arcangeli <andrea@suse.de>
4 (C) 2002 David Woodhouse <dwmw2@infradead.org>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or

--- 12 unchanged lines hidden (view full) ---

21*/
22
23#include <linux/rbtree.h>
24#include <linux/module.h>
25
26static void __rb_rotate_left(struct rb_node *node, struct rb_root *root)
27{
28 struct rb_node *right = node->rb_right;
29 struct rb_node *parent = rb_parent(node);
29
30 if ((node->rb_right = right->rb_left))
30
31 if ((node->rb_right = right->rb_left))
31 right->rb_left->rb_parent = node;
32 rb_set_parent(right->rb_left, node);
32 right->rb_left = node;
33
33 right->rb_left = node;
34
34 if ((right->rb_parent = node->rb_parent))
35 rb_set_parent(right, parent);
36
37 if (parent)
35 {
38 {
36 if (node == node->rb_parent->rb_left)
37 node->rb_parent->rb_left = right;
39 if (node == parent->rb_left)
40 parent->rb_left = right;
38 else
41 else
39 node->rb_parent->rb_right = right;
42 parent->rb_right = right;
40 }
41 else
42 root->rb_node = right;
43 }
44 else
45 root->rb_node = right;
43 node->rb_parent = right;
46 rb_set_parent(node, right);
44}
45
46static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
47{
48 struct rb_node *left = node->rb_left;
47}
48
49static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
50{
51 struct rb_node *left = node->rb_left;
52 struct rb_node *parent = rb_parent(node);
49
50 if ((node->rb_left = left->rb_right))
53
54 if ((node->rb_left = left->rb_right))
51 left->rb_right->rb_parent = node;
55 rb_set_parent(left->rb_right, node);
52 left->rb_right = node;
53
56 left->rb_right = node;
57
54 if ((left->rb_parent = node->rb_parent))
58 rb_set_parent(left, parent);
59
60 if (parent)
55 {
61 {
56 if (node == node->rb_parent->rb_right)
57 node->rb_parent->rb_right = left;
62 if (node == parent->rb_right)
63 parent->rb_right = left;
58 else
64 else
59 node->rb_parent->rb_left = left;
65 parent->rb_left = left;
60 }
61 else
62 root->rb_node = left;
66 }
67 else
68 root->rb_node = left;
63 node->rb_parent = left;
69 rb_set_parent(node, left);
64}
65
66void rb_insert_color(struct rb_node *node, struct rb_root *root)
67{
68 struct rb_node *parent, *gparent;
69
70}
71
72void rb_insert_color(struct rb_node *node, struct rb_root *root)
73{
74 struct rb_node *parent, *gparent;
75
70 while ((parent = node->rb_parent) && parent->rb_color == RB_RED)
76 while ((parent = rb_parent(node)) && rb_is_red(parent))
71 {
77 {
72 gparent = parent->rb_parent;
78 gparent = rb_parent(parent);
73
74 if (parent == gparent->rb_left)
75 {
76 {
77 register struct rb_node *uncle = gparent->rb_right;
79
80 if (parent == gparent->rb_left)
81 {
82 {
83 register struct rb_node *uncle = gparent->rb_right;
78 if (uncle && uncle->rb_color == RB_RED)
84 if (uncle && rb_is_red(uncle))
79 {
85 {
80 uncle->rb_color = RB_BLACK;
81 parent->rb_color = RB_BLACK;
82 gparent->rb_color = RB_RED;
86 rb_set_black(uncle);
87 rb_set_black(parent);
88 rb_set_red(gparent);
83 node = gparent;
84 continue;
85 }
86 }
87
88 if (parent->rb_right == node)
89 {
90 register struct rb_node *tmp;
91 __rb_rotate_left(parent, root);
92 tmp = parent;
93 parent = node;
94 node = tmp;
95 }
96
89 node = gparent;
90 continue;
91 }
92 }
93
94 if (parent->rb_right == node)
95 {
96 register struct rb_node *tmp;
97 __rb_rotate_left(parent, root);
98 tmp = parent;
99 parent = node;
100 node = tmp;
101 }
102
97 parent->rb_color = RB_BLACK;
98 gparent->rb_color = RB_RED;
103 rb_set_black(parent);
104 rb_set_red(gparent);
99 __rb_rotate_right(gparent, root);
100 } else {
101 {
102 register struct rb_node *uncle = gparent->rb_left;
105 __rb_rotate_right(gparent, root);
106 } else {
107 {
108 register struct rb_node *uncle = gparent->rb_left;
103 if (uncle && uncle->rb_color == RB_RED)
109 if (uncle && rb_is_red(uncle))
104 {
110 {
105 uncle->rb_color = RB_BLACK;
106 parent->rb_color = RB_BLACK;
107 gparent->rb_color = RB_RED;
111 rb_set_black(uncle);
112 rb_set_black(parent);
113 rb_set_red(gparent);
108 node = gparent;
109 continue;
110 }
111 }
112
113 if (parent->rb_left == node)
114 {
115 register struct rb_node *tmp;
116 __rb_rotate_right(parent, root);
117 tmp = parent;
118 parent = node;
119 node = tmp;
120 }
121
114 node = gparent;
115 continue;
116 }
117 }
118
119 if (parent->rb_left == node)
120 {
121 register struct rb_node *tmp;
122 __rb_rotate_right(parent, root);
123 tmp = parent;
124 parent = node;
125 node = tmp;
126 }
127
122 parent->rb_color = RB_BLACK;
123 gparent->rb_color = RB_RED;
128 rb_set_black(parent);
129 rb_set_red(gparent);
124 __rb_rotate_left(gparent, root);
125 }
126 }
127
130 __rb_rotate_left(gparent, root);
131 }
132 }
133
128 root->rb_node->rb_color = RB_BLACK;
134 rb_set_black(root->rb_node);
129}
130EXPORT_SYMBOL(rb_insert_color);
131
132static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
133 struct rb_root *root)
134{
135 struct rb_node *other;
136
135}
136EXPORT_SYMBOL(rb_insert_color);
137
138static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
139 struct rb_root *root)
140{
141 struct rb_node *other;
142
137 while ((!node || node->rb_color == RB_BLACK) && node != root->rb_node)
143 while ((!node || rb_is_black(node)) && node != root->rb_node)
138 {
139 if (parent->rb_left == node)
140 {
141 other = parent->rb_right;
144 {
145 if (parent->rb_left == node)
146 {
147 other = parent->rb_right;
142 if (other->rb_color == RB_RED)
148 if (rb_is_red(other))
143 {
149 {
144 other->rb_color = RB_BLACK;
145 parent->rb_color = RB_RED;
150 rb_set_black(other);
151 rb_set_red(parent);
146 __rb_rotate_left(parent, root);
147 other = parent->rb_right;
148 }
152 __rb_rotate_left(parent, root);
153 other = parent->rb_right;
154 }
149 if ((!other->rb_left ||
150 other->rb_left->rb_color == RB_BLACK)
151 && (!other->rb_right ||
152 other->rb_right->rb_color == RB_BLACK))
155 if ((!other->rb_left || rb_is_black(other->rb_left)) &&
156 (!other->rb_right || rb_is_black(other->rb_right)))
153 {
157 {
154 other->rb_color = RB_RED;
158 rb_set_red(other);
155 node = parent;
159 node = parent;
156 parent = node->rb_parent;
160 parent = rb_parent(node);
157 }
158 else
159 {
161 }
162 else
163 {
160 if (!other->rb_right ||
161 other->rb_right->rb_color == RB_BLACK)
164 if (!other->rb_right || rb_is_black(other->rb_right))
162 {
165 {
163 register struct rb_node *o_left;
166 struct rb_node *o_left;
164 if ((o_left = other->rb_left))
167 if ((o_left = other->rb_left))
165 o_left->rb_color = RB_BLACK;
166 other->rb_color = RB_RED;
168 rb_set_black(o_left);
169 rb_set_red(other);
167 __rb_rotate_right(other, root);
168 other = parent->rb_right;
169 }
170 __rb_rotate_right(other, root);
171 other = parent->rb_right;
172 }
170 other->rb_color = parent->rb_color;
171 parent->rb_color = RB_BLACK;
173 rb_set_colour(other, rb_colour(parent));
174 rb_set_black(parent);
172 if (other->rb_right)
175 if (other->rb_right)
173 other->rb_right->rb_color = RB_BLACK;
176 rb_set_black(other->rb_right);
174 __rb_rotate_left(parent, root);
175 node = root->rb_node;
176 break;
177 }
178 }
179 else
180 {
181 other = parent->rb_left;
177 __rb_rotate_left(parent, root);
178 node = root->rb_node;
179 break;
180 }
181 }
182 else
183 {
184 other = parent->rb_left;
182 if (other->rb_color == RB_RED)
185 if (rb_is_red(other))
183 {
186 {
184 other->rb_color = RB_BLACK;
185 parent->rb_color = RB_RED;
187 rb_set_black(other);
188 rb_set_red(parent);
186 __rb_rotate_right(parent, root);
187 other = parent->rb_left;
188 }
189 __rb_rotate_right(parent, root);
190 other = parent->rb_left;
191 }
189 if ((!other->rb_left ||
190 other->rb_left->rb_color == RB_BLACK)
191 && (!other->rb_right ||
192 other->rb_right->rb_color == RB_BLACK))
192 if ((!other->rb_left || rb_is_black(other->rb_left)) &&
193 (!other->rb_right || rb_is_black(other->rb_right)))
193 {
194 {
194 other->rb_color = RB_RED;
195 rb_set_red(other);
195 node = parent;
196 node = parent;
196 parent = node->rb_parent;
197 parent = rb_parent(node);
197 }
198 else
199 {
198 }
199 else
200 {
200 if (!other->rb_left ||
201 other->rb_left->rb_color == RB_BLACK)
201 if (!other->rb_left || rb_is_black(other->rb_left))
202 {
203 register struct rb_node *o_right;
204 if ((o_right = other->rb_right))
202 {
203 register struct rb_node *o_right;
204 if ((o_right = other->rb_right))
205 o_right->rb_color = RB_BLACK;
206 other->rb_color = RB_RED;
205 rb_set_black(o_right);
206 rb_set_red(other);
207 __rb_rotate_left(other, root);
208 other = parent->rb_left;
209 }
207 __rb_rotate_left(other, root);
208 other = parent->rb_left;
209 }
210 other->rb_color = parent->rb_color;
211 parent->rb_color = RB_BLACK;
210 rb_set_colour(other, rb_colour(parent));
211 rb_set_black(parent);
212 if (other->rb_left)
212 if (other->rb_left)
213 other->rb_left->rb_color = RB_BLACK;
213 rb_set_black(other->rb_left);
214 __rb_rotate_right(parent, root);
215 node = root->rb_node;
216 break;
217 }
218 }
219 }
220 if (node)
214 __rb_rotate_right(parent, root);
215 node = root->rb_node;
216 break;
217 }
218 }
219 }
220 if (node)
221 node->rb_color = RB_BLACK;
221 rb_set_black(node);
222}
223
224void rb_erase(struct rb_node *node, struct rb_root *root)
225{
226 struct rb_node *child, *parent;
227 int color;
228
229 if (!node->rb_left)
230 child = node->rb_right;
231 else if (!node->rb_right)
232 child = node->rb_left;
233 else
234 {
235 struct rb_node *old = node, *left;
236
237 node = node->rb_right;
238 while ((left = node->rb_left) != NULL)
239 node = left;
240 child = node->rb_right;
222}
223
224void rb_erase(struct rb_node *node, struct rb_root *root)
225{
226 struct rb_node *child, *parent;
227 int color;
228
229 if (!node->rb_left)
230 child = node->rb_right;
231 else if (!node->rb_right)
232 child = node->rb_left;
233 else
234 {
235 struct rb_node *old = node, *left;
236
237 node = node->rb_right;
238 while ((left = node->rb_left) != NULL)
239 node = left;
240 child = node->rb_right;
241 parent = node->rb_parent;
242 color = node->rb_color;
241 parent = rb_parent(node);
242 color = rb_colour(node);
243
244 if (child)
243
244 if (child)
245 child->rb_parent = parent;
246
247 if (node->rb_parent == old) {
245 rb_set_parent(child, parent);
246 if (parent == old) {
248 parent->rb_right = child;
249 parent = node;
247 parent->rb_right = child;
248 parent = node;
250 } else
249 } else
251 parent->rb_left = child;
252
250 parent->rb_left = child;
251
253 node->rb_parent = old->rb_parent;
254 node->rb_color = old->rb_color;
252 node->rb_parent_colour = old->rb_parent_colour;
255 node->rb_right = old->rb_right;
256 node->rb_left = old->rb_left;
257
253 node->rb_right = old->rb_right;
254 node->rb_left = old->rb_left;
255
258 if (old->rb_parent)
256 if (rb_parent(old))
259 {
257 {
260 if (old->rb_parent->rb_left == old)
261 old->rb_parent->rb_left = node;
258 if (rb_parent(old)->rb_left == old)
259 rb_parent(old)->rb_left = node;
262 else
260 else
263 old->rb_parent->rb_right = node;
261 rb_parent(old)->rb_right = node;
264 } else
265 root->rb_node = node;
266
262 } else
263 root->rb_node = node;
264
267 old->rb_left->rb_parent = node;
265 rb_set_parent(old->rb_left, node);
268 if (old->rb_right)
266 if (old->rb_right)
269 old->rb_right->rb_parent = node;
267 rb_set_parent(old->rb_right, node);
270 goto color;
271 }
272
268 goto color;
269 }
270
273 parent = node->rb_parent;
274 color = node->rb_color;
271 parent = rb_parent(node);
272 color = rb_colour(node);
275
276 if (child)
273
274 if (child)
277 child->rb_parent = parent;
275 rb_set_parent(child, parent);
278 if (parent)
279 {
280 if (parent->rb_left == node)
281 parent->rb_left = child;
282 else
283 parent->rb_right = child;
284 }
285 else

--- 31 unchanged lines hidden (view full) ---

317 while (n->rb_right)
318 n = n->rb_right;
319 return n;
320}
321EXPORT_SYMBOL(rb_last);
322
323struct rb_node *rb_next(struct rb_node *node)
324{
276 if (parent)
277 {
278 if (parent->rb_left == node)
279 parent->rb_left = child;
280 else
281 parent->rb_right = child;
282 }
283 else

--- 31 unchanged lines hidden (view full) ---

315 while (n->rb_right)
316 n = n->rb_right;
317 return n;
318}
319EXPORT_SYMBOL(rb_last);
320
321struct rb_node *rb_next(struct rb_node *node)
322{
323 struct rb_node *parent;
324
325 /* If we have a right-hand child, go down and then left as far
326 as we can. */
327 if (node->rb_right) {
328 node = node->rb_right;
329 while (node->rb_left)
330 node=node->rb_left;
331 return node;
332 }
333
334 /* No right-hand children. Everything down and left is
335 smaller than us, so any 'next' node must be in the general
336 direction of our parent. Go up the tree; any time the
337 ancestor is a right-hand child of its parent, keep going
338 up. First time it's a left-hand child of its parent, said
339 parent is our 'next' node. */
325 /* If we have a right-hand child, go down and then left as far
326 as we can. */
327 if (node->rb_right) {
328 node = node->rb_right;
329 while (node->rb_left)
330 node=node->rb_left;
331 return node;
332 }
333
334 /* No right-hand children. Everything down and left is
335 smaller than us, so any 'next' node must be in the general
336 direction of our parent. Go up the tree; any time the
337 ancestor is a right-hand child of its parent, keep going
338 up. First time it's a left-hand child of its parent, said
339 parent is our 'next' node. */
340 while (node->rb_parent && node == node->rb_parent->rb_right)
341 node = node->rb_parent;
340 while ((parent = rb_parent(node)) && node == parent->rb_right)
341 node = parent;
342
342
343 return node->rb_parent;
343 return parent;
344}
345EXPORT_SYMBOL(rb_next);
346
347struct rb_node *rb_prev(struct rb_node *node)
348{
344}
345EXPORT_SYMBOL(rb_next);
346
347struct rb_node *rb_prev(struct rb_node *node)
348{
349 struct rb_node *parent;
350
349 /* If we have a left-hand child, go down and then right as far
350 as we can. */
351 if (node->rb_left) {
352 node = node->rb_left;
353 while (node->rb_right)
354 node=node->rb_right;
355 return node;
356 }
357
358 /* No left-hand children. Go up till we find an ancestor which
359 is a right-hand child of its parent */
351 /* If we have a left-hand child, go down and then right as far
352 as we can. */
353 if (node->rb_left) {
354 node = node->rb_left;
355 while (node->rb_right)
356 node=node->rb_right;
357 return node;
358 }
359
360 /* No left-hand children. Go up till we find an ancestor which
361 is a right-hand child of its parent */
360 while (node->rb_parent && node == node->rb_parent->rb_left)
361 node = node->rb_parent;
362 while ((parent = rb_parent(node)) && node == parent->rb_left)
363 node = parent;
362
364
363 return node->rb_parent;
365 return parent;
364}
365EXPORT_SYMBOL(rb_prev);
366
367void rb_replace_node(struct rb_node *victim, struct rb_node *new,
368 struct rb_root *root)
369{
366}
367EXPORT_SYMBOL(rb_prev);
368
369void rb_replace_node(struct rb_node *victim, struct rb_node *new,
370 struct rb_root *root)
371{
370 struct rb_node *parent = victim->rb_parent;
372 struct rb_node *parent = rb_parent(victim);
371
372 /* Set the surrounding nodes to point to the replacement */
373 if (parent) {
374 if (victim == parent->rb_left)
375 parent->rb_left = new;
376 else
377 parent->rb_right = new;
378 } else {
379 root->rb_node = new;
380 }
381 if (victim->rb_left)
373
374 /* Set the surrounding nodes to point to the replacement */
375 if (parent) {
376 if (victim == parent->rb_left)
377 parent->rb_left = new;
378 else
379 parent->rb_right = new;
380 } else {
381 root->rb_node = new;
382 }
383 if (victim->rb_left)
382 victim->rb_left->rb_parent = new;
384 rb_set_parent(victim->rb_left, new);
383 if (victim->rb_right)
385 if (victim->rb_right)
384 victim->rb_right->rb_parent = new;
386 rb_set_parent(victim->rb_right, new);
385
386 /* Copy the pointers/colour from the victim to the replacement */
387 *new = *victim;
388}
389EXPORT_SYMBOL(rb_replace_node);
387
388 /* Copy the pointers/colour from the victim to the replacement */
389 *new = *victim;
390}
391EXPORT_SYMBOL(rb_replace_node);