Sun, 21 May 2023 14:03:21 +0200
add empty list implementation - fixes #258
universe@549 | 1 | /* |
universe@549 | 2 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. |
universe@549 | 3 | * |
universe@549 | 4 | * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved. |
universe@549 | 5 | * |
universe@549 | 6 | * Redistribution and use in source and binary forms, with or without |
universe@549 | 7 | * modification, are permitted provided that the following conditions are met: |
universe@549 | 8 | * |
universe@549 | 9 | * 1. Redistributions of source code must retain the above copyright |
universe@549 | 10 | * notice, this list of conditions and the following disclaimer. |
universe@549 | 11 | * |
universe@549 | 12 | * 2. Redistributions in binary form must reproduce the above copyright |
universe@549 | 13 | * notice, this list of conditions and the following disclaimer in the |
universe@549 | 14 | * documentation and/or other materials provided with the distribution. |
universe@549 | 15 | * |
universe@549 | 16 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
universe@549 | 17 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
universe@549 | 18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
universe@549 | 19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
universe@549 | 20 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
universe@549 | 21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
universe@549 | 22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
universe@549 | 23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
universe@549 | 24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
universe@549 | 25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
universe@549 | 26 | * POSSIBILITY OF SUCH DAMAGE. |
universe@549 | 27 | */ |
universe@549 | 28 | |
universe@549 | 29 | #include <string.h> |
universe@549 | 30 | #include "cx/hash_map.h" |
universe@550 | 31 | #include "cx/utils.h" |
universe@549 | 32 | |
universe@658 | 33 | struct cx_hash_map_element_s { |
universe@658 | 34 | /** A pointer to the next element in the current bucket. */ |
universe@658 | 35 | struct cx_hash_map_element_s *next; |
universe@658 | 36 | |
universe@658 | 37 | /** The corresponding key. */ |
universe@658 | 38 | CxHashKey key; |
universe@658 | 39 | |
universe@658 | 40 | /** The value data. */ |
universe@658 | 41 | char data[]; |
universe@658 | 42 | }; |
universe@658 | 43 | |
universe@550 | 44 | static void cx_hash_map_clear(struct cx_map_s *map) { |
universe@550 | 45 | struct cx_hash_map_s *hash_map = (struct cx_hash_map_s *) map; |
universe@550 | 46 | cx_for_n(i, hash_map->bucket_count) { |
universe@550 | 47 | struct cx_hash_map_element_s *elem = hash_map->buckets[i]; |
universe@550 | 48 | if (elem != NULL) { |
universe@550 | 49 | do { |
universe@550 | 50 | struct cx_hash_map_element_s *next = elem->next; |
universe@686 | 51 | // invoke the destructor |
universe@686 | 52 | cx_invoke_destructor(map, elem->data); |
universe@550 | 53 | // free the key data |
universe@690 | 54 | cxFree(map->allocator, (void *) elem->key.data); |
universe@550 | 55 | // free the node |
universe@550 | 56 | cxFree(map->allocator, elem); |
universe@550 | 57 | // proceed |
universe@550 | 58 | elem = next; |
universe@550 | 59 | } while (elem != NULL); |
universe@550 | 60 | |
universe@550 | 61 | // do not leave a dangling pointer |
universe@550 | 62 | hash_map->buckets[i] = NULL; |
universe@550 | 63 | } |
universe@550 | 64 | } |
universe@550 | 65 | map->size = 0; |
universe@550 | 66 | } |
universe@550 | 67 | |
universe@550 | 68 | static void cx_hash_map_destructor(struct cx_map_s *map) { |
universe@550 | 69 | struct cx_hash_map_s *hash_map = (struct cx_hash_map_s *) map; |
universe@550 | 70 | |
universe@550 | 71 | // free the buckets |
universe@550 | 72 | cx_hash_map_clear(map); |
universe@550 | 73 | cxFree(map->allocator, hash_map->buckets); |
universe@550 | 74 | |
universe@550 | 75 | // free the map structure |
universe@550 | 76 | cxFree(map->allocator, map); |
universe@550 | 77 | } |
universe@550 | 78 | |
universe@550 | 79 | static int cx_hash_map_put( |
universe@550 | 80 | CxMap *map, |
universe@563 | 81 | CxHashKey key, |
universe@550 | 82 | void *value |
universe@550 | 83 | ) { |
universe@550 | 84 | struct cx_hash_map_s *hash_map = (struct cx_hash_map_s *) map; |
universe@686 | 85 | CxAllocator const *allocator = map->allocator; |
universe@550 | 86 | |
universe@563 | 87 | unsigned hash = key.hash; |
universe@563 | 88 | if (hash == 0) { |
universe@563 | 89 | cx_hash_murmur(&key); |
universe@563 | 90 | hash = key.hash; |
universe@563 | 91 | } |
universe@550 | 92 | |
universe@550 | 93 | size_t slot = hash % hash_map->bucket_count; |
universe@550 | 94 | struct cx_hash_map_element_s *elm = hash_map->buckets[slot]; |
universe@550 | 95 | struct cx_hash_map_element_s *prev = NULL; |
universe@550 | 96 | |
universe@550 | 97 | while (elm != NULL && elm->key.hash < hash) { |
universe@550 | 98 | prev = elm; |
universe@550 | 99 | elm = elm->next; |
universe@550 | 100 | } |
universe@550 | 101 | |
universe@575 | 102 | if (elm != NULL && elm->key.hash == hash && elm->key.len == key.len && |
universe@690 | 103 | memcmp(elm->key.data, key.data, key.len) == 0) { |
universe@574 | 104 | // overwrite existing element |
universe@685 | 105 | if (map->store_pointer) { |
universe@658 | 106 | memcpy(elm->data, &value, sizeof(void *)); |
universe@658 | 107 | } else { |
universe@677 | 108 | memcpy(elm->data, value, map->item_size); |
universe@658 | 109 | } |
universe@574 | 110 | } else { |
universe@575 | 111 | // allocate new element |
universe@658 | 112 | struct cx_hash_map_element_s *e = cxMalloc( |
universe@658 | 113 | allocator, |
universe@677 | 114 | sizeof(struct cx_hash_map_element_s) + map->item_size |
universe@658 | 115 | ); |
universe@550 | 116 | if (e == NULL) { |
universe@550 | 117 | return -1; |
universe@550 | 118 | } |
universe@550 | 119 | |
universe@550 | 120 | // write the value |
universe@685 | 121 | if (map->store_pointer) { |
universe@658 | 122 | memcpy(e->data, &value, sizeof(void *)); |
universe@658 | 123 | } else { |
universe@677 | 124 | memcpy(e->data, value, map->item_size); |
universe@658 | 125 | } |
universe@550 | 126 | |
universe@550 | 127 | // copy the key |
universe@550 | 128 | void *kd = cxMalloc(allocator, key.len); |
universe@550 | 129 | if (kd == NULL) { |
universe@550 | 130 | return -1; |
universe@550 | 131 | } |
universe@690 | 132 | memcpy(kd, key.data, key.len); |
universe@690 | 133 | e->key.data = kd; |
universe@550 | 134 | e->key.len = key.len; |
universe@550 | 135 | e->key.hash = hash; |
universe@550 | 136 | |
universe@550 | 137 | // insert the element into the linked list |
universe@550 | 138 | if (prev == NULL) { |
universe@550 | 139 | hash_map->buckets[slot] = e; |
universe@550 | 140 | } else { |
universe@550 | 141 | prev->next = e; |
universe@550 | 142 | } |
universe@550 | 143 | e->next = elm; |
universe@550 | 144 | |
universe@550 | 145 | // increase the size |
universe@550 | 146 | map->size++; |
universe@550 | 147 | } |
universe@550 | 148 | |
universe@550 | 149 | return 0; |
universe@550 | 150 | } |
universe@549 | 151 | |
universe@551 | 152 | static void cx_hash_map_unlink( |
universe@551 | 153 | struct cx_hash_map_s *hash_map, |
universe@551 | 154 | size_t slot, |
universe@551 | 155 | struct cx_hash_map_element_s *prev, |
universe@551 | 156 | struct cx_hash_map_element_s *elm |
universe@551 | 157 | ) { |
universe@551 | 158 | // unlink |
universe@551 | 159 | if (prev == NULL) { |
universe@551 | 160 | hash_map->buckets[slot] = elm->next; |
universe@551 | 161 | } else { |
universe@551 | 162 | prev->next = elm->next; |
universe@551 | 163 | } |
universe@551 | 164 | // free element |
universe@690 | 165 | cxFree(hash_map->base.allocator, (void *) elm->key.data); |
universe@551 | 166 | cxFree(hash_map->base.allocator, elm); |
universe@551 | 167 | // decrease size |
universe@551 | 168 | hash_map->base.size--; |
universe@551 | 169 | } |
universe@551 | 170 | |
universe@549 | 171 | /** |
universe@550 | 172 | * Helper function to avoid code duplication. |
universe@549 | 173 | * |
universe@550 | 174 | * @param map the map |
universe@550 | 175 | * @param key the key to look up |
universe@550 | 176 | * @param remove flag indicating whether the looked up entry shall be removed |
universe@686 | 177 | * @param destroy flag indicating whether the destructor shall be invoked |
universe@658 | 178 | * @return a pointer to the value corresponding to the key or \c NULL |
universe@549 | 179 | */ |
universe@550 | 180 | static void *cx_hash_map_get_remove( |
universe@550 | 181 | CxMap *map, |
universe@563 | 182 | CxHashKey key, |
universe@686 | 183 | bool remove, |
universe@686 | 184 | bool destroy |
universe@550 | 185 | ) { |
universe@550 | 186 | struct cx_hash_map_s *hash_map = (struct cx_hash_map_s *) map; |
universe@550 | 187 | |
universe@563 | 188 | unsigned hash = key.hash; |
universe@563 | 189 | if (hash == 0) { |
universe@563 | 190 | cx_hash_murmur(&key); |
universe@563 | 191 | hash = key.hash; |
universe@563 | 192 | } |
universe@550 | 193 | |
universe@550 | 194 | size_t slot = hash % hash_map->bucket_count; |
universe@550 | 195 | struct cx_hash_map_element_s *elm = hash_map->buckets[slot]; |
universe@550 | 196 | struct cx_hash_map_element_s *prev = NULL; |
universe@550 | 197 | while (elm && elm->key.hash <= hash) { |
universe@550 | 198 | if (elm->key.hash == hash && elm->key.len == key.len) { |
universe@690 | 199 | if (memcmp(elm->key.data, key.data, key.len) == 0) { |
universe@658 | 200 | void *data = NULL; |
universe@686 | 201 | if (destroy) { |
universe@686 | 202 | cx_invoke_destructor(map, elm->data); |
universe@686 | 203 | } else { |
universe@686 | 204 | if (map->store_pointer) { |
universe@686 | 205 | data = *(void **) elm->data; |
universe@686 | 206 | } else { |
universe@686 | 207 | data = elm->data; |
universe@686 | 208 | } |
universe@658 | 209 | } |
universe@550 | 210 | if (remove) { |
universe@551 | 211 | cx_hash_map_unlink(hash_map, slot, prev, elm); |
universe@550 | 212 | } |
universe@550 | 213 | return data; |
universe@550 | 214 | } |
universe@550 | 215 | } |
universe@550 | 216 | prev = elm; |
universe@550 | 217 | elm = prev->next; |
universe@550 | 218 | } |
universe@550 | 219 | |
universe@550 | 220 | return NULL; |
universe@549 | 221 | } |
universe@550 | 222 | |
universe@550 | 223 | static void *cx_hash_map_get( |
universe@550 | 224 | CxMap const *map, |
universe@563 | 225 | CxHashKey key |
universe@550 | 226 | ) { |
universe@688 | 227 | // we can safely cast, because we know the map stays untouched |
universe@686 | 228 | return cx_hash_map_get_remove((CxMap *) map, key, false, false); |
universe@550 | 229 | } |
universe@550 | 230 | |
universe@550 | 231 | static void *cx_hash_map_remove( |
universe@550 | 232 | CxMap *map, |
universe@686 | 233 | CxHashKey key, |
universe@686 | 234 | bool destroy |
universe@550 | 235 | ) { |
universe@686 | 236 | return cx_hash_map_get_remove(map, key, true, destroy); |
universe@550 | 237 | } |
universe@550 | 238 | |
universe@630 | 239 | static void *cx_hash_map_iter_current_entry(void const *it) { |
universe@630 | 240 | struct cx_iterator_s const *iter = it; |
universe@551 | 241 | // struct has to have a compatible signature |
universe@573 | 242 | return (struct cx_map_entry_s *) &(iter->kv_data); |
universe@551 | 243 | } |
universe@551 | 244 | |
universe@630 | 245 | static void *cx_hash_map_iter_current_key(void const *it) { |
universe@630 | 246 | struct cx_iterator_s const *iter = it; |
universe@551 | 247 | struct cx_hash_map_element_s *elm = iter->elem_handle; |
universe@551 | 248 | return &elm->key; |
universe@551 | 249 | } |
universe@551 | 250 | |
universe@630 | 251 | static void *cx_hash_map_iter_current_value(void const *it) { |
universe@630 | 252 | struct cx_iterator_s const *iter = it; |
universe@658 | 253 | struct cx_hash_map_s const *map = iter->src_handle; |
universe@551 | 254 | struct cx_hash_map_element_s *elm = iter->elem_handle; |
universe@685 | 255 | if (map->base.store_pointer) { |
universe@658 | 256 | return *(void **) elm->data; |
universe@658 | 257 | } else { |
universe@658 | 258 | return elm->data; |
universe@658 | 259 | } |
universe@551 | 260 | } |
universe@551 | 261 | |
universe@630 | 262 | static bool cx_hash_map_iter_valid(void const *it) { |
universe@630 | 263 | struct cx_iterator_s const *iter = it; |
universe@551 | 264 | return iter->elem_handle != NULL; |
universe@551 | 265 | } |
universe@551 | 266 | |
universe@630 | 267 | static void cx_hash_map_iter_next(void *it) { |
universe@630 | 268 | struct cx_iterator_s *iter = it; |
universe@551 | 269 | struct cx_hash_map_element_s *elm = iter->elem_handle; |
universe@551 | 270 | |
universe@551 | 271 | // remove current element, if asked |
universe@630 | 272 | if (iter->base.remove) { |
universe@630 | 273 | // obtain mutable pointer to the map |
universe@630 | 274 | struct cx_mut_iterator_s *miter = it; |
universe@630 | 275 | struct cx_hash_map_s *map = miter->src_handle; |
universe@630 | 276 | |
universe@551 | 277 | // clear the flag |
universe@630 | 278 | iter->base.remove = false; |
universe@551 | 279 | |
universe@551 | 280 | // determine the next element |
universe@551 | 281 | struct cx_hash_map_element_s *next = elm->next; |
universe@551 | 282 | |
universe@551 | 283 | // search the previous element |
universe@551 | 284 | struct cx_hash_map_element_s *prev = NULL; |
universe@551 | 285 | if (map->buckets[iter->slot] != elm) { |
universe@551 | 286 | prev = map->buckets[iter->slot]; |
universe@551 | 287 | while (prev->next != elm) { |
universe@551 | 288 | prev = prev->next; |
universe@551 | 289 | } |
universe@551 | 290 | } |
universe@551 | 291 | |
universe@686 | 292 | // destroy |
universe@686 | 293 | cx_invoke_destructor((struct cx_map_s *) map, elm->data); |
universe@686 | 294 | |
universe@551 | 295 | // unlink |
universe@551 | 296 | cx_hash_map_unlink(map, iter->slot, prev, elm); |
universe@551 | 297 | |
universe@551 | 298 | // advance |
universe@551 | 299 | elm = next; |
universe@551 | 300 | } else { |
universe@551 | 301 | // just advance |
universe@551 | 302 | elm = elm->next; |
universe@560 | 303 | iter->index++; |
universe@551 | 304 | } |
universe@551 | 305 | |
universe@560 | 306 | // search the next bucket, if required |
universe@630 | 307 | struct cx_hash_map_s const *map = iter->src_handle; |
universe@560 | 308 | while (elm == NULL && ++iter->slot < map->bucket_count) { |
universe@560 | 309 | elm = map->buckets[iter->slot]; |
universe@551 | 310 | } |
universe@551 | 311 | |
universe@560 | 312 | // fill the struct with the next element |
universe@551 | 313 | iter->elem_handle = elm; |
universe@551 | 314 | if (elm == NULL) { |
universe@551 | 315 | iter->kv_data.key = NULL; |
universe@551 | 316 | iter->kv_data.value = NULL; |
universe@551 | 317 | } else { |
universe@551 | 318 | iter->kv_data.key = &elm->key; |
universe@685 | 319 | if (map->base.store_pointer) { |
universe@658 | 320 | iter->kv_data.value = *(void **) elm->data; |
universe@658 | 321 | } else { |
universe@658 | 322 | iter->kv_data.value = elm->data; |
universe@658 | 323 | } |
universe@551 | 324 | } |
universe@551 | 325 | } |
universe@551 | 326 | |
universe@630 | 327 | static bool cx_hash_map_iter_flag_rm(void *it) { |
universe@630 | 328 | struct cx_iterator_base_s *iter = it; |
universe@630 | 329 | if (iter->mutating) { |
universe@630 | 330 | iter->remove = true; |
universe@630 | 331 | return true; |
universe@630 | 332 | } else { |
universe@630 | 333 | return false; |
universe@630 | 334 | } |
universe@630 | 335 | } |
universe@630 | 336 | |
universe@630 | 337 | static CxIterator cx_hash_map_iterator(CxMap const *map) { |
universe@550 | 338 | CxIterator iter; |
universe@551 | 339 | |
universe@551 | 340 | iter.src_handle = map; |
universe@630 | 341 | iter.base.valid = cx_hash_map_iter_valid; |
universe@630 | 342 | iter.base.next = cx_hash_map_iter_next; |
universe@630 | 343 | iter.base.current = cx_hash_map_iter_current_entry; |
universe@630 | 344 | iter.base.flag_removal = cx_hash_map_iter_flag_rm; |
universe@630 | 345 | iter.base.remove = false; |
universe@630 | 346 | iter.base.mutating = false; |
universe@551 | 347 | |
universe@551 | 348 | iter.slot = 0; |
universe@551 | 349 | iter.index = 0; |
universe@551 | 350 | |
universe@551 | 351 | if (map->size > 0) { |
universe@551 | 352 | struct cx_hash_map_s *hash_map = (struct cx_hash_map_s *) map; |
universe@560 | 353 | struct cx_hash_map_element_s *elm = hash_map->buckets[0]; |
olaf@665 | 354 | while (elm == NULL) { |
olaf@665 | 355 | elm = hash_map->buckets[++iter.slot]; |
universe@551 | 356 | } |
universe@554 | 357 | iter.elem_handle = elm; |
universe@554 | 358 | iter.kv_data.key = &elm->key; |
universe@685 | 359 | if (map->store_pointer) { |
universe@658 | 360 | iter.kv_data.value = *(void **) elm->data; |
universe@658 | 361 | } else { |
universe@658 | 362 | iter.kv_data.value = elm->data; |
universe@658 | 363 | } |
universe@551 | 364 | } else { |
universe@551 | 365 | iter.elem_handle = NULL; |
universe@551 | 366 | iter.kv_data.key = NULL; |
universe@551 | 367 | iter.kv_data.value = NULL; |
universe@551 | 368 | } |
universe@551 | 369 | |
universe@550 | 370 | return iter; |
universe@550 | 371 | } |
universe@550 | 372 | |
universe@630 | 373 | static CxIterator cx_hash_map_iterator_keys(CxMap const *map) { |
universe@551 | 374 | CxIterator iter = cx_hash_map_iterator(map); |
universe@630 | 375 | iter.base.current = cx_hash_map_iter_current_key; |
universe@550 | 376 | return iter; |
universe@550 | 377 | } |
universe@550 | 378 | |
universe@630 | 379 | static CxIterator cx_hash_map_iterator_values(CxMap const *map) { |
universe@551 | 380 | CxIterator iter = cx_hash_map_iterator(map); |
universe@630 | 381 | iter.base.current = cx_hash_map_iter_current_value; |
universe@630 | 382 | return iter; |
universe@630 | 383 | } |
universe@630 | 384 | |
universe@630 | 385 | static CxMutIterator cx_hash_map_mut_iterator(CxMap *map) { |
universe@630 | 386 | CxIterator it = cx_hash_map_iterator(map); |
universe@630 | 387 | it.base.mutating = true; |
universe@630 | 388 | |
universe@630 | 389 | // we know the iterators share the same memory layout |
universe@630 | 390 | CxMutIterator iter; |
universe@630 | 391 | memcpy(&iter, &it, sizeof(CxMutIterator)); |
universe@630 | 392 | return iter; |
universe@630 | 393 | } |
universe@630 | 394 | |
universe@630 | 395 | static CxMutIterator cx_hash_map_mut_iterator_keys(CxMap *map) { |
universe@630 | 396 | CxMutIterator iter = cx_hash_map_mut_iterator(map); |
universe@630 | 397 | iter.base.current = cx_hash_map_iter_current_key; |
universe@630 | 398 | return iter; |
universe@630 | 399 | } |
universe@630 | 400 | |
universe@630 | 401 | static CxMutIterator cx_hash_map_mut_iterator_values(CxMap *map) { |
universe@630 | 402 | CxMutIterator iter = cx_hash_map_mut_iterator(map); |
universe@630 | 403 | iter.base.current = cx_hash_map_iter_current_value; |
universe@550 | 404 | return iter; |
universe@550 | 405 | } |
universe@550 | 406 | |
universe@550 | 407 | static cx_map_class cx_hash_map_class = { |
universe@550 | 408 | cx_hash_map_destructor, |
universe@550 | 409 | cx_hash_map_clear, |
universe@550 | 410 | cx_hash_map_put, |
universe@550 | 411 | cx_hash_map_get, |
universe@550 | 412 | cx_hash_map_remove, |
universe@550 | 413 | cx_hash_map_iterator, |
universe@550 | 414 | cx_hash_map_iterator_keys, |
universe@550 | 415 | cx_hash_map_iterator_values, |
universe@630 | 416 | cx_hash_map_mut_iterator, |
universe@630 | 417 | cx_hash_map_mut_iterator_keys, |
universe@630 | 418 | cx_hash_map_mut_iterator_values, |
universe@550 | 419 | }; |
universe@550 | 420 | |
universe@550 | 421 | CxMap *cxHashMapCreate( |
universe@691 | 422 | CxAllocator const *allocator, |
universe@658 | 423 | size_t itemsize, |
universe@550 | 424 | size_t buckets |
universe@550 | 425 | ) { |
universe@550 | 426 | if (buckets == 0) { |
universe@550 | 427 | // implementation defined default |
universe@550 | 428 | buckets = 16; |
universe@550 | 429 | } |
universe@550 | 430 | |
universe@688 | 431 | struct cx_hash_map_s *map = cxCalloc(allocator, 1, |
universe@688 | 432 | sizeof(struct cx_hash_map_s)); |
universe@550 | 433 | if (map == NULL) return NULL; |
universe@550 | 434 | |
universe@550 | 435 | // initialize hash map members |
universe@550 | 436 | map->bucket_count = buckets; |
universe@688 | 437 | map->buckets = cxCalloc(allocator, buckets, |
universe@688 | 438 | sizeof(struct cx_hash_map_element_s *)); |
universe@550 | 439 | if (map->buckets == NULL) { |
universe@550 | 440 | cxFree(allocator, map); |
universe@550 | 441 | return NULL; |
universe@550 | 442 | } |
universe@550 | 443 | |
universe@550 | 444 | // initialize base members |
universe@550 | 445 | map->base.cl = &cx_hash_map_class; |
universe@550 | 446 | map->base.allocator = allocator; |
universe@668 | 447 | |
universe@668 | 448 | if (itemsize > 0) { |
universe@685 | 449 | map->base.store_pointer = false; |
universe@677 | 450 | map->base.item_size = itemsize; |
universe@668 | 451 | } else { |
universe@685 | 452 | map->base.store_pointer = true; |
universe@677 | 453 | map->base.item_size = sizeof(void *); |
universe@668 | 454 | } |
universe@550 | 455 | |
universe@550 | 456 | return (CxMap *) map; |
universe@550 | 457 | } |
universe@562 | 458 | |
universe@562 | 459 | int cxMapRehash(CxMap *map) { |
universe@562 | 460 | struct cx_hash_map_s *hash_map = (struct cx_hash_map_s *) map; |
universe@562 | 461 | if (map->size > ((hash_map->bucket_count * 3) >> 2)) { |
universe@562 | 462 | |
universe@562 | 463 | size_t new_bucket_count = (map->size * 5) >> 1; |
universe@688 | 464 | struct cx_hash_map_element_s **new_buckets = cxCalloc( |
universe@688 | 465 | map->allocator, |
universe@688 | 466 | new_bucket_count, sizeof(struct cx_hash_map_element_s *) |
universe@688 | 467 | ); |
universe@562 | 468 | |
universe@562 | 469 | if (new_buckets == NULL) { |
universe@562 | 470 | return 1; |
universe@562 | 471 | } |
universe@562 | 472 | |
universe@562 | 473 | // iterate through the elements and assign them to their new slots |
universe@562 | 474 | cx_for_n(slot, hash_map->bucket_count) { |
universe@562 | 475 | struct cx_hash_map_element_s *elm = hash_map->buckets[slot]; |
universe@562 | 476 | while (elm != NULL) { |
universe@562 | 477 | struct cx_hash_map_element_s *next = elm->next; |
universe@562 | 478 | size_t new_slot = elm->key.hash % new_bucket_count; |
universe@562 | 479 | |
universe@562 | 480 | // find position where to insert |
universe@562 | 481 | struct cx_hash_map_element_s *bucket_next = new_buckets[new_slot]; |
universe@562 | 482 | struct cx_hash_map_element_s *bucket_prev = NULL; |
universe@688 | 483 | while (bucket_next != NULL && |
universe@688 | 484 | bucket_next->key.hash < elm->key.hash) { |
universe@562 | 485 | bucket_prev = bucket_next; |
universe@562 | 486 | bucket_next = bucket_next->next; |
universe@562 | 487 | } |
universe@562 | 488 | |
universe@562 | 489 | // insert |
universe@562 | 490 | if (bucket_prev == NULL) { |
universe@562 | 491 | elm->next = new_buckets[new_slot]; |
universe@562 | 492 | new_buckets[new_slot] = elm; |
universe@562 | 493 | } else { |
universe@562 | 494 | bucket_prev->next = elm; |
universe@562 | 495 | elm->next = bucket_next; |
universe@562 | 496 | } |
universe@562 | 497 | |
universe@562 | 498 | // advance |
universe@562 | 499 | elm = next; |
universe@562 | 500 | } |
universe@562 | 501 | } |
universe@562 | 502 | |
universe@562 | 503 | // assign result to the map |
universe@562 | 504 | hash_map->bucket_count = new_bucket_count; |
universe@562 | 505 | cxFree(map->allocator, hash_map->buckets); |
universe@562 | 506 | hash_map->buckets = new_buckets; |
universe@562 | 507 | } |
universe@562 | 508 | return 0; |
universe@562 | 509 | } |