rbtree

annotate src/rbtree.c @ 10:b45febfd2922

find changesets by author, revision, files, or words in the commit message
fixed all the conversion warnings
author John Tsiombikas <nuclear@member.fsf.org>
date Mon, 16 Apr 2012 00:30:59 +0300
parents 2c0baa1fd419
children 5b955b3a4675
rev   line source
nuclear@0 1 #include <stdio.h>
nuclear@0 2 #include <stdlib.h>
nuclear@10 3 #include <stdint.h>
nuclear@0 4 #include <string.h>
nuclear@0 5 #include "rbtree.h"
nuclear@0 6
nuclear@10 7 #define INT2PTR(x) ((void*)(intptr_t)(x))
nuclear@10 8 #define PTR2INT(x) ((int)(intptr_t)(x))
nuclear@0 9
nuclear@0 10 struct rbtree {
nuclear@0 11 struct rbnode *root;
nuclear@0 12
nuclear@0 13 rb_alloc_func_t alloc;
nuclear@0 14 rb_free_func_t free;
nuclear@0 15
nuclear@0 16 rb_cmp_func_t cmp;
nuclear@0 17 rb_del_func_t del;
nuclear@0 18 void *del_cls;
nuclear@0 19
nuclear@0 20 struct rbnode *rstack, *iter;
nuclear@0 21 };
nuclear@0 22
nuclear@10 23 static int cmpaddr(const void *ap, const void *bp);
nuclear@10 24 static int cmpint(const void *ap, const void *bp);
nuclear@0 25
nuclear@0 26 static int count_nodes(struct rbnode *node);
nuclear@0 27 static void del_tree(struct rbnode *node, void (*delfunc)(struct rbnode*, void*), void *cls);
nuclear@0 28 static struct rbnode *insert(struct rbtree *rb, struct rbnode *tree, void *key, void *data);
nuclear@0 29 static struct rbnode *delete(struct rbtree *rb, struct rbnode *tree, void *key);
nuclear@3 30 /*static struct rbnode *find(struct rbtree *rb, struct rbnode *node, void *key);*/
nuclear@0 31 static void traverse(struct rbnode *node, void (*func)(struct rbnode*, void*), void *cls);
nuclear@0 32
nuclear@0 33 struct rbtree *rb_create(rb_cmp_func_t cmp_func)
nuclear@0 34 {
nuclear@0 35 struct rbtree *rb;
nuclear@0 36
nuclear@0 37 if(!(rb = malloc(sizeof *rb))) {
nuclear@0 38 return 0;
nuclear@0 39 }
nuclear@0 40 if(rb_init(rb, cmp_func) == -1) {
nuclear@0 41 free(rb);
nuclear@0 42 return 0;
nuclear@0 43 }
nuclear@0 44 return rb;
nuclear@0 45 }
nuclear@0 46
nuclear@0 47 void rb_free(struct rbtree *rb)
nuclear@0 48 {
nuclear@0 49 rb_destroy(rb);
nuclear@0 50 free(rb);
nuclear@0 51 }
nuclear@0 52
nuclear@0 53
nuclear@0 54 int rb_init(struct rbtree *rb, rb_cmp_func_t cmp_func)
nuclear@0 55 {
nuclear@0 56 memset(rb, 0, sizeof *rb);
nuclear@0 57
nuclear@0 58 if(cmp_func == RB_KEY_INT) {
nuclear@0 59 rb->cmp = cmpint;
nuclear@0 60 } else if(cmp_func == RB_KEY_STRING) {
nuclear@0 61 rb->cmp = (rb_cmp_func_t)strcmp;
nuclear@0 62 } else {
nuclear@0 63 rb->cmp = cmpaddr;
nuclear@0 64 }
nuclear@0 65
nuclear@0 66 rb->alloc = malloc;
nuclear@0 67 rb->free = free;
nuclear@0 68 return 0;
nuclear@0 69 }
nuclear@0 70
nuclear@0 71 void rb_destroy(struct rbtree *rb)
nuclear@0 72 {
nuclear@0 73 del_tree(rb->root, rb->del, rb->del_cls);
nuclear@0 74 }
nuclear@0 75
nuclear@0 76 void rb_set_allocator(struct rbtree *rb, rb_alloc_func_t alloc, rb_free_func_t free)
nuclear@0 77 {
nuclear@0 78 rb->alloc = alloc;
nuclear@0 79 rb->free = free;
nuclear@0 80 }
nuclear@0 81
nuclear@0 82
nuclear@0 83 void rb_set_compare_func(struct rbtree *rb, rb_cmp_func_t func)
nuclear@0 84 {
nuclear@0 85 rb->cmp = func;
nuclear@0 86 }
nuclear@0 87
nuclear@0 88 void rb_set_delete_func(struct rbtree *rb, rb_del_func_t func, void *cls)
nuclear@0 89 {
nuclear@0 90 rb->del = func;
nuclear@0 91 rb->del_cls = cls;
nuclear@0 92 }
nuclear@0 93
nuclear@5 94
nuclear@5 95 void rb_clear(struct rbtree *rb)
nuclear@5 96 {
nuclear@5 97 del_tree(rb->root, rb->del, rb->del_cls);
nuclear@5 98 rb->root = 0;
nuclear@5 99 }
nuclear@5 100
nuclear@5 101 int rb_copy(struct rbtree *dest, struct rbtree *src)
nuclear@5 102 {
nuclear@5 103 struct rbnode *node;
nuclear@5 104
nuclear@5 105 rb_clear(dest);
nuclear@5 106 rb_begin(src);
nuclear@5 107 while((node = rb_next(src))) {
nuclear@5 108 if(rb_insert(dest, node->key, node->data) == -1) {
nuclear@5 109 return -1;
nuclear@5 110 }
nuclear@5 111 }
nuclear@5 112 return 0;
nuclear@5 113 }
nuclear@5 114
nuclear@0 115 int rb_size(struct rbtree *rb)
nuclear@0 116 {
nuclear@0 117 return count_nodes(rb->root);
nuclear@0 118 }
nuclear@0 119
nuclear@0 120 int rb_insert(struct rbtree *rb, void *key, void *data)
nuclear@0 121 {
nuclear@0 122 rb->root = insert(rb, rb->root, key, data);
nuclear@0 123 rb->root->red = 0;
nuclear@0 124 return 0;
nuclear@0 125 }
nuclear@0 126
nuclear@0 127 int rb_inserti(struct rbtree *rb, int key, void *data)
nuclear@0 128 {
nuclear@0 129 rb->root = insert(rb, rb->root, INT2PTR(key), data);
nuclear@0 130 rb->root->red = 0;
nuclear@0 131 return 0;
nuclear@0 132 }
nuclear@0 133
nuclear@0 134
nuclear@0 135 int rb_delete(struct rbtree *rb, void *key)
nuclear@0 136 {
nuclear@0 137 rb->root = delete(rb, rb->root, key);
nuclear@0 138 rb->root->red = 0;
nuclear@0 139 return 0;
nuclear@0 140 }
nuclear@0 141
nuclear@0 142 int rb_deletei(struct rbtree *rb, int key)
nuclear@0 143 {
nuclear@0 144 rb->root = delete(rb, rb->root, INT2PTR(key));
nuclear@0 145 rb->root->red = 0;
nuclear@0 146 return 0;
nuclear@0 147 }
nuclear@0 148
nuclear@0 149
nuclear@0 150 void *rb_find(struct rbtree *rb, void *key)
nuclear@0 151 {
nuclear@3 152 struct rbnode *node = rb->root;
nuclear@3 153
nuclear@3 154 while(node) {
nuclear@3 155 int cmp = rb->cmp(key, node->key);
nuclear@3 156 if(cmp == 0) {
nuclear@3 157 return node;
nuclear@3 158 }
nuclear@3 159 node = cmp < 0 ? node->left : node->right;
nuclear@3 160 }
nuclear@3 161 return 0;
nuclear@0 162 }
nuclear@0 163
nuclear@0 164 void *rb_findi(struct rbtree *rb, int key)
nuclear@0 165 {
nuclear@3 166 return rb_find(rb, INT2PTR(key));
nuclear@0 167 }
nuclear@0 168
nuclear@0 169
nuclear@0 170 void rb_foreach(struct rbtree *rb, void (*func)(struct rbnode*, void*), void *cls)
nuclear@0 171 {
nuclear@0 172 traverse(rb->root, func, cls);
nuclear@0 173 }
nuclear@0 174
nuclear@0 175
nuclear@0 176 struct rbnode *rb_root(struct rbtree *rb)
nuclear@0 177 {
nuclear@0 178 return rb->root;
nuclear@0 179 }
nuclear@0 180
nuclear@0 181 void rb_begin(struct rbtree *rb)
nuclear@0 182 {
nuclear@0 183 rb->rstack = 0;
nuclear@0 184 rb->iter = rb->root;
nuclear@0 185 }
nuclear@0 186
nuclear@0 187 #define push(sp, x) ((x)->next = (sp), (sp) = (x))
nuclear@0 188 #define pop(sp) ((sp) = (sp)->next)
nuclear@0 189 #define top(sp) (sp)
nuclear@0 190
nuclear@0 191 struct rbnode *rb_next(struct rbtree *rb)
nuclear@0 192 {
nuclear@0 193 struct rbnode *res = 0;
nuclear@0 194
nuclear@0 195 while(rb->rstack || rb->iter) {
nuclear@0 196 if(rb->iter) {
nuclear@0 197 push(rb->rstack, rb->iter);
nuclear@0 198 rb->iter = rb->iter->left;
nuclear@0 199 } else {
nuclear@0 200 rb->iter = top(rb->rstack);
nuclear@0 201 pop(rb->rstack);
nuclear@0 202 res = rb->iter;
nuclear@0 203 rb->iter = rb->iter->right;
nuclear@0 204 break;
nuclear@0 205 }
nuclear@0 206 }
nuclear@0 207 return res;
nuclear@0 208 }
nuclear@0 209
nuclear@0 210 void *rb_node_key(struct rbnode *node)
nuclear@0 211 {
nuclear@0 212 return node ? node->key : 0;
nuclear@0 213 }
nuclear@0 214
nuclear@0 215 int rb_node_keyi(struct rbnode *node)
nuclear@0 216 {
nuclear@0 217 return node ? PTR2INT(node->key) : 0;
nuclear@0 218 }
nuclear@0 219
nuclear@0 220 void *rb_node_data(struct rbnode *node)
nuclear@0 221 {
nuclear@0 222 return node ? node->data : 0;
nuclear@0 223 }
nuclear@0 224
nuclear@10 225 static int cmpaddr(const void *ap, const void *bp)
nuclear@0 226 {
nuclear@0 227 return ap < bp ? -1 : (ap > bp ? 1 : 0);
nuclear@0 228 }
nuclear@0 229
nuclear@10 230 static int cmpint(const void *ap, const void *bp)
nuclear@0 231 {
nuclear@0 232 return PTR2INT(ap) - PTR2INT(bp);
nuclear@0 233 }
nuclear@0 234
nuclear@0 235
nuclear@0 236 /* ---- left-leaning 2-3 red-black implementation ---- */
nuclear@0 237
nuclear@0 238 /* helper prototypes */
nuclear@0 239 static int is_red(struct rbnode *tree);
nuclear@0 240 static void color_flip(struct rbnode *tree);
nuclear@0 241 static struct rbnode *rot_left(struct rbnode *a);
nuclear@0 242 static struct rbnode *rot_right(struct rbnode *a);
nuclear@0 243 static struct rbnode *find_min(struct rbnode *tree);
nuclear@0 244 static struct rbnode *del_min(struct rbtree *rb, struct rbnode *tree);
nuclear@0 245 /*static struct rbnode *move_red_right(struct rbnode *tree);*/
nuclear@0 246 static struct rbnode *move_red_left(struct rbnode *tree);
nuclear@0 247 static struct rbnode *fix_up(struct rbnode *tree);
nuclear@0 248
nuclear@0 249 static int count_nodes(struct rbnode *node)
nuclear@0 250 {
nuclear@0 251 if(!node)
nuclear@0 252 return 0;
nuclear@0 253
nuclear@0 254 return 1 + count_nodes(node->left) + count_nodes(node->right);
nuclear@0 255 }
nuclear@0 256
nuclear@0 257 static void del_tree(struct rbnode *node, rb_del_func_t delfunc, void *cls)
nuclear@0 258 {
nuclear@0 259 if(!node)
nuclear@0 260 return;
nuclear@0 261
nuclear@0 262 del_tree(node->left, delfunc, cls);
nuclear@0 263 del_tree(node->right, delfunc, cls);
nuclear@0 264
nuclear@7 265 if(delfunc) {
nuclear@7 266 delfunc(node, cls);
nuclear@7 267 }
nuclear@0 268 free(node);
nuclear@0 269 }
nuclear@0 270
nuclear@0 271 static struct rbnode *insert(struct rbtree *rb, struct rbnode *tree, void *key, void *data)
nuclear@0 272 {
nuclear@0 273 int cmp;
nuclear@0 274
nuclear@0 275 if(!tree) {
nuclear@0 276 struct rbnode *node = rb->alloc(sizeof *node);
nuclear@0 277 node->red = 1;
nuclear@0 278 node->key = key;
nuclear@0 279 node->data = data;
nuclear@0 280 node->left = node->right = 0;
nuclear@0 281 return node;
nuclear@0 282 }
nuclear@0 283
nuclear@0 284 cmp = rb->cmp(key, tree->key);
nuclear@0 285
nuclear@0 286 if(cmp < 0) {
nuclear@0 287 tree->left = insert(rb, tree->left, key, data);
nuclear@0 288 } else if(cmp > 0) {
nuclear@0 289 tree->right = insert(rb, tree->right, key, data);
nuclear@0 290 } else {
nuclear@0 291 tree->data = data;
nuclear@0 292 }
nuclear@0 293
nuclear@0 294 /* fix right-leaning reds */
nuclear@0 295 if(is_red(tree->right)) {
nuclear@0 296 tree = rot_left(tree);
nuclear@0 297 }
nuclear@0 298 /* fix two reds in a row */
nuclear@0 299 if(is_red(tree->left) && is_red(tree->left->left)) {
nuclear@0 300 tree = rot_right(tree);
nuclear@0 301 }
nuclear@0 302
nuclear@0 303 /* if 4-node, split it by color inversion */
nuclear@0 304 if(is_red(tree->left) && is_red(tree->right)) {
nuclear@0 305 color_flip(tree);
nuclear@0 306 }
nuclear@0 307
nuclear@0 308 return tree;
nuclear@0 309 }
nuclear@0 310
nuclear@0 311 static struct rbnode *delete(struct rbtree *rb, struct rbnode *tree, void *key)
nuclear@0 312 {
nuclear@0 313 int cmp;
nuclear@0 314
nuclear@0 315 if(!tree) {
nuclear@0 316 return 0;
nuclear@0 317 }
nuclear@0 318
nuclear@0 319 cmp = rb->cmp(key, tree->key);
nuclear@0 320
nuclear@0 321 if(cmp < 0) {
nuclear@0 322 if(!is_red(tree->left) && !is_red(tree->left->left)) {
nuclear@0 323 tree = move_red_left(tree);
nuclear@0 324 }
nuclear@0 325 tree->left = delete(rb, tree->left, key);
nuclear@0 326 } else {
nuclear@0 327 /* need reds on the right */
nuclear@0 328 if(is_red(tree->left)) {
nuclear@0 329 tree = rot_right(tree);
nuclear@0 330 }
nuclear@0 331
nuclear@0 332 /* found it at the bottom (XXX what certifies left is null?) */
nuclear@0 333 if(cmp == 0 && !tree->right) {
nuclear@0 334 if(rb->del) {
nuclear@0 335 rb->del(tree, rb->del_cls);
nuclear@0 336 }
nuclear@0 337 rb->free(tree);
nuclear@0 338 return 0;
nuclear@0 339 }
nuclear@0 340
nuclear@0 341 if(!is_red(tree->right) && !is_red(tree->right->left)) {
nuclear@0 342 tree = move_red_left(tree);
nuclear@0 343 }
nuclear@0 344
nuclear@0 345 if(key == tree->key) {
nuclear@0 346 struct rbnode *rmin = find_min(tree->right);
nuclear@0 347 tree->key = rmin->key;
nuclear@0 348 tree->data = rmin->data;
nuclear@0 349 tree->right = del_min(rb, tree->right);
nuclear@0 350 } else {
nuclear@0 351 tree->right = delete(rb, tree->right, key);
nuclear@0 352 }
nuclear@0 353 }
nuclear@0 354
nuclear@0 355 return fix_up(tree);
nuclear@0 356 }
nuclear@0 357
nuclear@3 358 /*static struct rbnode *find(struct rbtree *rb, struct rbnode *node, void *key)
nuclear@0 359 {
nuclear@0 360 int cmp;
nuclear@0 361
nuclear@0 362 if(!node)
nuclear@0 363 return 0;
nuclear@0 364
nuclear@0 365 if((cmp = rb->cmp(key, node->key)) == 0) {
nuclear@0 366 return node;
nuclear@0 367 }
nuclear@0 368 return find(rb, cmp < 0 ? node->left : node->right, key);
nuclear@3 369 }*/
nuclear@0 370
nuclear@0 371 static void traverse(struct rbnode *node, void (*func)(struct rbnode*, void*), void *cls)
nuclear@0 372 {
nuclear@0 373 if(!node)
nuclear@0 374 return;
nuclear@0 375
nuclear@0 376 traverse(node->left, func, cls);
nuclear@0 377 func(node, cls);
nuclear@0 378 traverse(node->right, func, cls);
nuclear@0 379 }
nuclear@0 380
nuclear@0 381 /* helpers */
nuclear@0 382
nuclear@0 383 static int is_red(struct rbnode *tree)
nuclear@0 384 {
nuclear@0 385 return tree && tree->red;
nuclear@0 386 }
nuclear@0 387
nuclear@0 388 static void color_flip(struct rbnode *tree)
nuclear@0 389 {
nuclear@0 390 tree->red = !tree->red;
nuclear@0 391 tree->left->red = !tree->left->red;
nuclear@0 392 tree->right->red = !tree->right->red;
nuclear@0 393 }
nuclear@0 394
nuclear@0 395 static struct rbnode *rot_left(struct rbnode *a)
nuclear@0 396 {
nuclear@0 397 struct rbnode *b = a->right;
nuclear@0 398 a->right = b->left;
nuclear@0 399 b->left = a;
nuclear@0 400 b->red = a->red;
nuclear@0 401 a->red = 1;
nuclear@0 402 return b;
nuclear@0 403 }
nuclear@0 404
nuclear@0 405 static struct rbnode *rot_right(struct rbnode *a)
nuclear@0 406 {
nuclear@0 407 struct rbnode *b = a->left;
nuclear@0 408 a->left = b->right;
nuclear@0 409 b->right = a;
nuclear@0 410 b->red = a->red;
nuclear@0 411 a->red = 1;
nuclear@0 412 return b;
nuclear@0 413 }
nuclear@0 414
nuclear@0 415 static struct rbnode *find_min(struct rbnode *tree)
nuclear@0 416 {
nuclear@3 417 struct rbnode *node;
nuclear@3 418
nuclear@3 419 if(!tree)
nuclear@3 420 return 0;
nuclear@3 421
nuclear@3 422 while(node->left) {
nuclear@3 423 node = node->left;
nuclear@0 424 }
nuclear@3 425 return node;
nuclear@0 426 }
nuclear@0 427
nuclear@0 428 static struct rbnode *del_min(struct rbtree *rb, struct rbnode *tree)
nuclear@0 429 {
nuclear@0 430 if(!tree->left) {
nuclear@0 431 if(rb->del) {
nuclear@0 432 rb->del(tree->left, rb->del_cls);
nuclear@0 433 }
nuclear@0 434 rb->free(tree->left);
nuclear@0 435 return 0;
nuclear@0 436 }
nuclear@0 437
nuclear@0 438 /* make sure we've got red (3/4-nodes) at the left side so we can delete at the bottom */
nuclear@0 439 if(!is_red(tree->left) && !is_red(tree->left->left)) {
nuclear@0 440 tree = move_red_left(tree);
nuclear@0 441 }
nuclear@0 442 tree->left = del_min(rb, tree->left);
nuclear@0 443
nuclear@0 444 /* fix right-reds, red-reds, and split 4-nodes on the way up */
nuclear@0 445 return fix_up(tree);
nuclear@0 446 }
nuclear@0 447
nuclear@0 448 #if 0
nuclear@0 449 /* push a red link on this node to the right */
nuclear@0 450 static struct rbnode *move_red_right(struct rbnode *tree)
nuclear@0 451 {
nuclear@0 452 /* flipping it makes both children go red, so we have a red to the right */
nuclear@0 453 color_flip(tree);
nuclear@0 454
nuclear@0 455 /* if after the flip we've got a red-red situation to the left, fix it */
nuclear@0 456 if(is_red(tree->left->left)) {
nuclear@0 457 tree = rot_right(tree);
nuclear@0 458 color_flip(tree);
nuclear@0 459 }
nuclear@0 460 return tree;
nuclear@0 461 }
nuclear@0 462 #endif
nuclear@0 463
nuclear@0 464 /* push a red link on this node to the left */
nuclear@0 465 static struct rbnode *move_red_left(struct rbnode *tree)
nuclear@0 466 {
nuclear@0 467 /* flipping it makes both children go red, so we have a red to the left */
nuclear@0 468 color_flip(tree);
nuclear@0 469
nuclear@0 470 /* if after the flip we've got a red-red on the right-left, fix it */
nuclear@0 471 if(is_red(tree->right->left)) {
nuclear@0 472 tree->right = rot_right(tree->right);
nuclear@0 473 tree = rot_left(tree);
nuclear@0 474 color_flip(tree);
nuclear@0 475 }
nuclear@0 476 return tree;
nuclear@0 477 }
nuclear@0 478
nuclear@0 479 static struct rbnode *fix_up(struct rbnode *tree)
nuclear@0 480 {
nuclear@0 481 /* fix right-leaning */
nuclear@0 482 if(is_red(tree->right)) {
nuclear@0 483 tree = rot_left(tree);
nuclear@0 484 }
nuclear@0 485 /* change invalid red-red pairs into a proper 4-node */
nuclear@0 486 if(is_red(tree->left) && is_red(tree->left->left)) {
nuclear@0 487 tree = rot_right(tree);
nuclear@0 488 }
nuclear@0 489 /* split 4-nodes */
nuclear@0 490 if(is_red(tree->left) && is_red(tree->right)) {
nuclear@0 491 color_flip(tree);
nuclear@0 492 }
nuclear@0 493 return tree;
nuclear@0 494 }