1 | /** |
---|
2 | * @file rtems/score/rbtree.inl |
---|
3 | * |
---|
4 | * This include file contains the bodies of the routines which are |
---|
5 | * associated with Red-Black Trees and inlined. |
---|
6 | * |
---|
7 | * @note The routines in this file are ordered from simple |
---|
8 | * to complex. No other RBTree Handler routine is referenced |
---|
9 | * unless it has already been defined. |
---|
10 | */ |
---|
11 | |
---|
12 | /* |
---|
13 | * Copyright (c) 2010 Gedare Bloom. |
---|
14 | * |
---|
15 | * The license and distribution terms for this file may be |
---|
16 | * found in the file LICENSE in this distribution or at |
---|
17 | * http://www.rtems.com/license/LICENSE. |
---|
18 | * |
---|
19 | * $Id$ |
---|
20 | */ |
---|
21 | |
---|
22 | #ifndef _RTEMS_SCORE_RBTREE_H |
---|
23 | # error "Never use <rtems/score/rbtree.inl> directly; include <rtems/score/rbtree.h> instead." |
---|
24 | #endif |
---|
25 | |
---|
26 | #ifndef _RTEMS_SCORE_RBTREE_INL |
---|
27 | #define _RTEMS_SCORE_RBTREE_INL |
---|
28 | |
---|
29 | /** |
---|
30 | * @addtogroup ScoreRBTree |
---|
31 | * @{ |
---|
32 | */ |
---|
33 | |
---|
34 | /** @brief Set off rbtree |
---|
35 | * |
---|
36 | * This function sets the parent and child fields of the @a node to NULL |
---|
37 | * indicating the @a node is not part of a rbtree. |
---|
38 | * |
---|
39 | */ |
---|
40 | RTEMS_INLINE_ROUTINE void _RBTree_Set_off_rbtree( |
---|
41 | RBTree_Node *node |
---|
42 | ) |
---|
43 | { |
---|
44 | node->parent = node->child[RBT_LEFT] = node->child[RBT_RIGHT] = NULL; |
---|
45 | } |
---|
46 | |
---|
47 | /** @brief Is the Node off RBTree |
---|
48 | * |
---|
49 | * This function returns true if the @a node is not on a rbtree. A @a node is |
---|
50 | * off rbtree if the parent and child fields are set to NULL. |
---|
51 | */ |
---|
52 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_node_off_rbtree( |
---|
53 | const RBTree_Node *node |
---|
54 | ) |
---|
55 | { |
---|
56 | return (node->parent == NULL) && (node->child[RBT_LEFT] == NULL) && (node->child[RBT_RIGHT] == NULL); |
---|
57 | } |
---|
58 | |
---|
59 | /** @brief Are Two Nodes Equal |
---|
60 | * |
---|
61 | * This function returns true if @a left and @a right are equal, |
---|
62 | * and false otherwise. |
---|
63 | */ |
---|
64 | RTEMS_INLINE_ROUTINE bool _RBTree_Are_nodes_equal( |
---|
65 | const RBTree_Node *left, |
---|
66 | const RBTree_Node *right |
---|
67 | ) |
---|
68 | { |
---|
69 | return left == right; |
---|
70 | } |
---|
71 | |
---|
72 | /** @brief Is this RBTree Control Pointer Null |
---|
73 | * |
---|
74 | * This function returns true if @a the_rbtree is NULL and false otherwise. |
---|
75 | */ |
---|
76 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_null( |
---|
77 | const RBTree_Control *the_rbtree |
---|
78 | ) |
---|
79 | { |
---|
80 | return (the_rbtree == NULL); |
---|
81 | } |
---|
82 | |
---|
83 | /** @brief Is the RBTree Node Pointer NULL |
---|
84 | * |
---|
85 | * This function returns true if @a the_node is NULL and false otherwise. |
---|
86 | */ |
---|
87 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_null_node( |
---|
88 | const RBTree_Node *the_node |
---|
89 | ) |
---|
90 | { |
---|
91 | return (the_node == NULL); |
---|
92 | } |
---|
93 | |
---|
94 | |
---|
95 | /** @brief Return pointer to RBTree's root node |
---|
96 | * |
---|
97 | * This function returns a pointer to the root node of @a the_rbtree. |
---|
98 | */ |
---|
99 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Root( |
---|
100 | RBTree_Control *the_rbtree |
---|
101 | ) |
---|
102 | { |
---|
103 | return the_rbtree->root; |
---|
104 | } |
---|
105 | |
---|
106 | /** @brief Return pointer to RBTree's First node |
---|
107 | * |
---|
108 | * This function returns a pointer to the first node on @a the_rbtree, |
---|
109 | * where @a dir specifies whether to return the minimum (0) or maximum (1). |
---|
110 | */ |
---|
111 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_First( |
---|
112 | RBTree_Control *the_rbtree, |
---|
113 | RBTree_Direction dir |
---|
114 | ) |
---|
115 | { |
---|
116 | return the_rbtree->first[dir]; |
---|
117 | } |
---|
118 | |
---|
119 | /** @brief Return pointer to the parent of this node |
---|
120 | * |
---|
121 | * This function returns a pointer to the parent node of @a the_node. |
---|
122 | */ |
---|
123 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Parent( |
---|
124 | RBTree_Node *the_node |
---|
125 | ) |
---|
126 | { |
---|
127 | if (!the_node->parent->parent) return NULL; |
---|
128 | return the_node->parent; |
---|
129 | } |
---|
130 | |
---|
131 | /** @brief Return pointer to the left of this node |
---|
132 | * |
---|
133 | * This function returns a pointer to the left node of this node. |
---|
134 | * |
---|
135 | * @param[in] the_node is the node to be operated upon. |
---|
136 | * |
---|
137 | * @return This method returns the left node on the rbtree. |
---|
138 | */ |
---|
139 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Left( |
---|
140 | RBTree_Node *the_node |
---|
141 | ) |
---|
142 | { |
---|
143 | return the_node->child[RBT_LEFT]; |
---|
144 | } |
---|
145 | |
---|
146 | /** @brief Return pointer to the right of this node |
---|
147 | * |
---|
148 | * This function returns a pointer to the right node of this node. |
---|
149 | * |
---|
150 | * @param[in] the_node is the node to be operated upon. |
---|
151 | * |
---|
152 | * @return This method returns the right node on the rbtree. |
---|
153 | */ |
---|
154 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Right( |
---|
155 | RBTree_Node *the_node |
---|
156 | ) |
---|
157 | { |
---|
158 | return the_node->child[RBT_RIGHT]; |
---|
159 | } |
---|
160 | |
---|
161 | /** @brief Is the RBTree Empty |
---|
162 | * |
---|
163 | * This function returns true if there are no nodes on @a the_rbtree and |
---|
164 | * false otherwise. |
---|
165 | * |
---|
166 | * @param[in] the_rbtree is the rbtree to be operated upon. |
---|
167 | * |
---|
168 | * @return This function returns true if there are no nodes on |
---|
169 | * @a the_rbtree and false otherwise. |
---|
170 | */ |
---|
171 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_empty( |
---|
172 | RBTree_Control *the_rbtree |
---|
173 | ) |
---|
174 | { |
---|
175 | return (the_rbtree->root == NULL); |
---|
176 | } |
---|
177 | |
---|
178 | /** @brief Is this the First Node on the RBTree |
---|
179 | * |
---|
180 | * This function returns true if @a the_node is the first node on |
---|
181 | * @a the_rbtree and false otherwise. @a dir specifies whether first means |
---|
182 | * minimum (0) or maximum (1). |
---|
183 | * |
---|
184 | */ |
---|
185 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_first( |
---|
186 | RBTree_Control *the_rbtree, |
---|
187 | const RBTree_Node *the_node, |
---|
188 | RBTree_Direction dir |
---|
189 | ) |
---|
190 | { |
---|
191 | return (the_node == _RBTree_First(the_rbtree, dir)); |
---|
192 | } |
---|
193 | |
---|
194 | /** @brief Is this node red? |
---|
195 | * |
---|
196 | * This function returns true if @a the_node is red and false otherwise. |
---|
197 | */ |
---|
198 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_red( |
---|
199 | const RBTree_Node *the_node |
---|
200 | ) |
---|
201 | { |
---|
202 | return (the_node && the_node->color == RBT_RED); |
---|
203 | } |
---|
204 | |
---|
205 | |
---|
206 | /** @brief Does this RBTree have only One Node |
---|
207 | * |
---|
208 | * This function returns true if there is only one node on @a the_rbtree and |
---|
209 | * false otherwise. |
---|
210 | * |
---|
211 | */ |
---|
212 | RTEMS_INLINE_ROUTINE bool _RBTree_Has_only_one_node( |
---|
213 | const RBTree_Control *the_rbtree |
---|
214 | ) |
---|
215 | { |
---|
216 | if(!the_rbtree) return NULL; /* TODO: expected behavior? */ |
---|
217 | return (the_rbtree->root->child[RBT_LEFT] == NULL && the_rbtree->root->child[RBT_RIGHT] == NULL); |
---|
218 | } |
---|
219 | |
---|
220 | /** @brief Is this Node the RBTree root |
---|
221 | * |
---|
222 | * This function returns true if @a the_node is the root of @a the_rbtree and |
---|
223 | * false otherwise. |
---|
224 | */ |
---|
225 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_root( |
---|
226 | RBTree_Control *the_rbtree, |
---|
227 | const RBTree_Node *the_node |
---|
228 | ) |
---|
229 | { |
---|
230 | return (the_node == _RBTree_Root(the_rbtree)); |
---|
231 | } |
---|
232 | |
---|
233 | /** @brief Initialize this RBTree as Empty |
---|
234 | * |
---|
235 | * This routine initializes @a the_rbtree to contain zero nodes. |
---|
236 | */ |
---|
237 | RTEMS_INLINE_ROUTINE void _RBTree_Initialize_empty( |
---|
238 | RBTree_Control *the_rbtree, |
---|
239 | RBTree_Compare_function compare_function, |
---|
240 | bool is_unique |
---|
241 | ) |
---|
242 | { |
---|
243 | the_rbtree->permanent_null = NULL; |
---|
244 | the_rbtree->root = NULL; |
---|
245 | the_rbtree->first[0] = NULL; |
---|
246 | the_rbtree->first[1] = NULL; |
---|
247 | the_rbtree->compare_function = compare_function; |
---|
248 | the_rbtree->is_unique = is_unique; |
---|
249 | } |
---|
250 | |
---|
251 | /** @brief Return a pointer to node's grandparent |
---|
252 | * |
---|
253 | * This function returns a pointer to the grandparent of @a the_node if it |
---|
254 | * exists, and NULL if not. |
---|
255 | * |
---|
256 | */ |
---|
257 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Grandparent( |
---|
258 | RBTree_Node *the_node |
---|
259 | ) |
---|
260 | { |
---|
261 | if(!the_node) return NULL; |
---|
262 | if(!(the_node->parent)) return NULL; |
---|
263 | if(!(the_node->parent->parent)) return NULL; |
---|
264 | if(!(the_node->parent->parent->parent)) return NULL; |
---|
265 | return(the_node->parent->parent); |
---|
266 | } |
---|
267 | |
---|
268 | /** @brief Return a pointer to node's sibling |
---|
269 | * |
---|
270 | * This function returns a pointer to the sibling of @a the_node if it |
---|
271 | * exists, and NULL if not. |
---|
272 | */ |
---|
273 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Sibling( |
---|
274 | RBTree_Node *the_node |
---|
275 | ) |
---|
276 | { |
---|
277 | if(!the_node) return NULL; |
---|
278 | if(!(the_node->parent)) return NULL; |
---|
279 | if(!(the_node->parent->parent)) return NULL; |
---|
280 | |
---|
281 | if(the_node == the_node->parent->child[RBT_LEFT]) |
---|
282 | return the_node->parent->child[RBT_RIGHT]; |
---|
283 | else |
---|
284 | return the_node->parent->child[RBT_LEFT]; |
---|
285 | } |
---|
286 | |
---|
287 | /** @brief Return a pointer to node's parent's sibling |
---|
288 | * |
---|
289 | * This function returns a pointer to the sibling of the parent of |
---|
290 | * @a the_node if it exists, and NULL if not. |
---|
291 | */ |
---|
292 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Parent_sibling( |
---|
293 | RBTree_Node *the_node |
---|
294 | ) |
---|
295 | { |
---|
296 | if(!the_node) return NULL; |
---|
297 | if(_RBTree_Grandparent(the_node) == NULL) return NULL; |
---|
298 | |
---|
299 | return _RBTree_Sibling(the_node->parent); |
---|
300 | } |
---|
301 | |
---|
302 | /** @brief Find the RBTree_Control header given a node in the tree |
---|
303 | * |
---|
304 | * This function returns a pointer to the header of the Red Black |
---|
305 | * Tree containing @a the_node if it exists, and NULL if not. |
---|
306 | */ |
---|
307 | RTEMS_INLINE_ROUTINE RBTree_Control *_RBTree_Find_header_unprotected( |
---|
308 | RBTree_Node *the_node |
---|
309 | ) |
---|
310 | { |
---|
311 | if(!the_node) return NULL; |
---|
312 | if(!(the_node->parent)) return NULL; |
---|
313 | while(the_node->parent) the_node = the_node->parent; |
---|
314 | return (RBTree_Control*)the_node; |
---|
315 | } |
---|
316 | |
---|
317 | /** @brief Find the node with given key in the tree |
---|
318 | * |
---|
319 | * This function returns a pointer to the node in @a the_rbtree |
---|
320 | * having key equal to key of @a the_node if it exists, |
---|
321 | * and NULL if not. @a the_node has to be made up before a search. |
---|
322 | * |
---|
323 | * @note If the tree is not unique and contains duplicate keys, the set |
---|
324 | * of duplicate keys acts as FIFO. |
---|
325 | */ |
---|
326 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Find_unprotected( |
---|
327 | RBTree_Control *the_rbtree, |
---|
328 | RBTree_Node *the_node |
---|
329 | ) |
---|
330 | { |
---|
331 | RBTree_Node* iter_node = the_rbtree->root; |
---|
332 | RBTree_Node* found = NULL; |
---|
333 | int compare_result; |
---|
334 | while (iter_node) { |
---|
335 | compare_result = the_rbtree->compare_function(the_node, iter_node); |
---|
336 | if (compare_result == 0) { |
---|
337 | found = iter_node; |
---|
338 | if ( the_rbtree->is_unique ) |
---|
339 | break; |
---|
340 | } |
---|
341 | |
---|
342 | RBTree_Direction dir = (compare_result == 1); |
---|
343 | iter_node = iter_node->child[dir]; |
---|
344 | } /* while(iter_node) */ |
---|
345 | |
---|
346 | return found; |
---|
347 | } |
---|
348 | |
---|
349 | /** @brief Find the nodes in-order predecessor |
---|
350 | * |
---|
351 | * This function returns a pointer to the in-order predecessor |
---|
352 | * of @a the_node if it exists, and NULL if not. |
---|
353 | */ |
---|
354 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Predecessor( |
---|
355 | RBTree_Node *the_node |
---|
356 | ) |
---|
357 | { |
---|
358 | RBTree_Node* iter_node; |
---|
359 | if (!the_node) return NULL; |
---|
360 | iter_node = the_node->child[RBT_LEFT]; |
---|
361 | if (!iter_node) return NULL; |
---|
362 | while (iter_node->child[RBT_RIGHT]) { |
---|
363 | iter_node = iter_node->child[RBT_RIGHT]; |
---|
364 | } |
---|
365 | return iter_node; |
---|
366 | } |
---|
367 | |
---|
368 | /** @brief Find the nodes in-order successor |
---|
369 | * |
---|
370 | * This function returns a pointer to the in-order successor |
---|
371 | * of @a the_node if it exists, and NULL if not. |
---|
372 | */ |
---|
373 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Successor( |
---|
374 | RBTree_Node *the_node |
---|
375 | ) |
---|
376 | { |
---|
377 | RBTree_Node* iter_node; |
---|
378 | if (!the_node) return NULL; |
---|
379 | iter_node = the_node->child[RBT_RIGHT]; |
---|
380 | if (!iter_node) return NULL; |
---|
381 | while (iter_node->child[RBT_LEFT]) { |
---|
382 | iter_node = iter_node->child[RBT_LEFT]; |
---|
383 | } |
---|
384 | return iter_node; |
---|
385 | } |
---|
386 | |
---|
387 | /** @brief Get the First Node (unprotected) |
---|
388 | * |
---|
389 | * This function removes the minimum or maximum node from the_rbtree and |
---|
390 | * returns a pointer to that node. It does NOT disable interrupts to ensure |
---|
391 | * the atomicity of the get operation. |
---|
392 | * |
---|
393 | * @param[in] the_rbtree is the rbtree to attempt to get the min node from. |
---|
394 | * @param[in] dir specifies whether to get minimum (0) or maximum (1) |
---|
395 | * |
---|
396 | * @return This method returns the min or max node on the rbtree, or NULL. |
---|
397 | * |
---|
398 | * @note This routine may return NULL if the RBTree is empty. |
---|
399 | */ |
---|
400 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Get_unprotected( |
---|
401 | RBTree_Control *the_rbtree, |
---|
402 | RBTree_Direction dir |
---|
403 | ) |
---|
404 | { |
---|
405 | RBTree_Node *the_node = the_rbtree->first[dir]; |
---|
406 | _RBTree_Extract_unprotected(the_rbtree, the_node); |
---|
407 | return the_node; |
---|
408 | } |
---|
409 | |
---|
410 | /** @brief Peek at the First Node (unprotected) |
---|
411 | * |
---|
412 | * This function returns a pointer to the first node, minimum if @a dir is 0 |
---|
413 | * or maximum if @a dir is 1, from @a the_rbtree without extracting it. |
---|
414 | * It does NOT disable interrupts to ensure the atomicity of the peek. |
---|
415 | * |
---|
416 | * @retval NULL if @a the_rbtree is empty. |
---|
417 | */ |
---|
418 | RTEMS_INLINE_ROUTINE RBTree_Node *_RBTree_Peek_unprotected( |
---|
419 | RBTree_Control *the_rbtree, |
---|
420 | RBTree_Direction dir |
---|
421 | ) |
---|
422 | { |
---|
423 | return(the_rbtree->first[dir]); |
---|
424 | } |
---|
425 | |
---|
426 | /** @brief Rotate the_node in the direction passed as second argument |
---|
427 | * |
---|
428 | * This routine rotates @a the_node to the direction @a dir, swapping |
---|
429 | * @a the_node with its child\[@a dir\]. |
---|
430 | */ |
---|
431 | RTEMS_INLINE_ROUTINE void _RBTree_Rotate( |
---|
432 | RBTree_Node *the_node, |
---|
433 | RBTree_Direction dir |
---|
434 | ) |
---|
435 | { |
---|
436 | RBTree_Node *c; |
---|
437 | if (the_node == NULL) return; |
---|
438 | if (the_node->child[(1-dir)] == NULL) return; |
---|
439 | |
---|
440 | c = the_node->child[(1-dir)]; |
---|
441 | the_node->child[(1-dir)] = c->child[dir]; |
---|
442 | |
---|
443 | if (c->child[dir]) |
---|
444 | c->child[dir]->parent = the_node; |
---|
445 | |
---|
446 | c->child[dir] = the_node; |
---|
447 | |
---|
448 | the_node->parent->child[the_node != the_node->parent->child[0]] = c; |
---|
449 | |
---|
450 | c->parent = the_node->parent; |
---|
451 | the_node->parent = c; |
---|
452 | } |
---|
453 | |
---|
454 | /** @brief Determines whether the tree is unique |
---|
455 | */ |
---|
456 | RTEMS_INLINE_ROUTINE bool _RBTree_Is_unique( |
---|
457 | RBTree_Control *the_rbtree |
---|
458 | ) |
---|
459 | { |
---|
460 | return( the_rbtree && the_rbtree->is_unique ); |
---|
461 | } |
---|
462 | /**@}*/ |
---|
463 | |
---|
464 | #endif |
---|
465 | /* end of include file */ |
---|