ucx/map.h

Sun, 17 May 2015 17:31:32 +0200

author
Mike Becker <universe@uap-core.de>
date
Sun, 17 May 2015 17:31:32 +0200
changeset 192
1e51558b9d09
parent 177
11ad03783baf
child 206
58b77eb51afd
permissions
-rw-r--r--

updated copyright notice + added files for upcoming AVL tree implementation

olaf@2 1 /*
universe@103 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
universe@103 3 *
universe@192 4 * Copyright 2015 Olaf Wintermann. All rights reserved.
universe@103 5 *
universe@103 6 * Redistribution and use in source and binary forms, with or without
universe@103 7 * modification, are permitted provided that the following conditions are met:
universe@103 8 *
universe@103 9 * 1. Redistributions of source code must retain the above copyright
universe@103 10 * notice, this list of conditions and the following disclaimer.
universe@103 11 *
universe@103 12 * 2. Redistributions in binary form must reproduce the above copyright
universe@103 13 * notice, this list of conditions and the following disclaimer in the
universe@103 14 * documentation and/or other materials provided with the distribution.
universe@103 15 *
universe@103 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@103 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@103 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@103 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@103 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@103 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@103 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@103 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@103 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@103 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@103 26 * POSSIBILITY OF SUCH DAMAGE.
olaf@2 27 */
olaf@2 28
universe@136 29 /**
universe@136 30 * @file map.h
universe@136 31 *
universe@136 32 * Hash map implementation.
universe@136 33 *
universe@136 34 * This implementation uses murmur hash 2 and separate chaining with linked
universe@136 35 * lists.
universe@136 36 *
universe@136 37 * @author Mike Becker
universe@136 38 * @author Olaf Wintermann
universe@136 39 */
universe@136 40
olaf@120 41 #ifndef UCX_MAP_H
olaf@120 42 #define UCX_MAP_H
olaf@2 43
olaf@20 44 #include "ucx.h"
olaf@20 45 #include "string.h"
universe@114 46 #include "allocator.h"
universe@41 47 #include <stdio.h>
olaf@20 48
olaf@2 49 #ifdef __cplusplus
olaf@2 50 extern "C" {
olaf@2 51 #endif
olaf@2 52
universe@138 53 /**
universe@138 54 * Loop statement for UCX maps.
universe@138 55 *
universe@138 56 * The <code>key</code> variable is implicitly defined, but the
universe@138 57 * <code>value</code> variable must be already declared as type information
universe@138 58 * cannot be inferred.
universe@138 59 *
universe@138 60 * @param key the variable name for the key
universe@138 61 * @param value the variable name for the value
universe@138 62 * @param iter an UcxMapIterator
universe@138 63 * @see ucx_map_iterator()
universe@138 64 */
universe@138 65 #define UCX_MAP_FOREACH(key,value,iter) \
universe@138 66 for(UcxKey key;ucx_map_iter_next(&iter,&key, (void**)&value);)
olaf@31 67
universe@138 68 /** Type for the UCX map. @see UcxMap */
olaf@31 69 typedef struct UcxMap UcxMap;
universe@146 70
universe@138 71 /** Type for a key of an UcxMap. @see UcxKey */
olaf@31 72 typedef struct UcxKey UcxKey;
universe@146 73
universe@138 74 /** Type for an element of an UcxMap. @see UcxMapElement */
olaf@31 75 typedef struct UcxMapElement UcxMapElement;
universe@146 76
universe@138 77 /** Type for an iterator over an UcxMap. @see UcxMapIterator */
olaf@31 78 typedef struct UcxMapIterator UcxMapIterator;
olaf@2 79
universe@138 80 /** Structure for the UCX map. */
olaf@20 81 struct UcxMap {
universe@138 82 /** An allocator that is used for the map elements. */
olaf@107 83 UcxAllocator *allocator;
universe@138 84 /** The array of map element lists. */
universe@29 85 UcxMapElement **map;
universe@138 86 /** The size of the map is the length of the element list array. */
olaf@20 87 size_t size;
universe@138 88 /** The count of elements currently stored in this map. */
olaf@45 89 size_t count;
olaf@20 90 };
olaf@2 91
universe@138 92 /** Structure for a key of an UcxMap. */
olaf@20 93 struct UcxKey {
universe@138 94 /** The key data. */
olaf@20 95 void *data;
universe@138 96 /** The length of the key data. */
olaf@20 97 size_t len;
universe@138 98 /** The hash value of the key data. */
olaf@20 99 int hash;
olaf@20 100 };
olaf@20 101
universe@138 102 /** Structure for an element of an UcxMap. */
olaf@20 103 struct UcxMapElement {
universe@138 104 /** The value data. */
olaf@20 105 void *data;
universe@146 106
universe@138 107 /** A pointer to the next element in the current list. */
olaf@20 108 UcxMapElement *next;
universe@146 109
universe@138 110 /** The corresponding key. */
olaf@20 111 UcxKey key;
olaf@20 112 };
olaf@20 113
universe@138 114 /** Structure for an iterator over an UcxMap. */
olaf@31 115 struct UcxMapIterator {
universe@138 116 /** The map to iterate over. */
olaf@31 117 UcxMap *map;
universe@146 118
universe@138 119 /** The current map element. */
olaf@31 120 UcxMapElement *cur;
universe@146 121
universe@138 122 /**
universe@138 123 * The current index of the element list array.
universe@138 124 * <b>Attention: </b> this is <b>NOT</b> the element index! Do <b>NOT</b>
universe@138 125 * manually iterate over the map by increasing this index. Use
universe@138 126 * ucx_map_iter_next().
universe@138 127 * @see UcxMap.map*/
universe@95 128 size_t index;
olaf@31 129 };
olaf@31 130
universe@136 131 /**
universe@136 132 * Creates a new hash map with the specified size.
universe@136 133 * @param size the size of the hash map
universe@136 134 * @return a pointer to the new hash map
universe@136 135 */
universe@136 136 UcxMap *ucx_map_new(size_t size);
olaf@20 137
universe@136 138 /**
universe@136 139 * Creates a new hash map with the specified size using an UcxAllocator.
olaf@137 140 * @param allocator the allocator to use
universe@136 141 * @param size the size of the hash map
universe@136 142 * @return a pointer to the new hash map
universe@136 143 */
olaf@137 144 UcxMap *ucx_map_new_a(UcxAllocator *allocator, size_t size);
universe@136 145
universe@136 146 /**
universe@136 147 * Frees a hash map.
universe@136 148 *
universe@136 149 * <b>Note:</b> the contents are <b>not</b> freed, use an UcxMempool for that
universe@136 150 * purpose.
universe@136 151 *
universe@136 152 * @param map the map to be freed
universe@136 153 */
universe@29 154 void ucx_map_free(UcxMap *map);
universe@136 155
universe@138 156 /**
universe@138 157 * Copies contents from a map to another map using a copy function.
universe@138 158 *
universe@138 159 * <b>Note:</b> The destination map does not need to be empty. However, if it
universe@138 160 * contains data with keys that are also present in the source map, the contents
universe@138 161 * are overwritten.
universe@138 162 *
universe@138 163 * @param from the source map
universe@138 164 * @param to the destination map
universe@138 165 * @param fnc the copy function or <code>NULL</code> if the pointer address
universe@138 166 * shall be copied
universe@138 167 * @param data additional data for the copy function
universe@138 168 * @return 0 on success or a non-zero value on memory allocation errors
universe@138 169 */
universe@67 170 int ucx_map_copy(UcxMap *restrict from, UcxMap *restrict to,
universe@67 171 copy_func fnc, void *data);
universe@138 172
universe@138 173 /**
universe@138 174 * Clones the map and rehashes if necessary.
universe@138 175 *
universe@138 176 * <b>Note:</b> In contrast to ucx_map_rehash() the load factor is irrelevant.
universe@138 177 * This function <i>always</i> ensures a new UcxMap.size of at least
universe@138 178 * 2.5*UcxMap.count.
universe@138 179 *
universe@138 180 * @param map the map to clone
universe@138 181 * @param fnc the copy function to use or <code>NULL</code> if the new and
universe@138 182 * the old map shall share the data pointers
universe@138 183 * @param data additional data for the copy function
universe@138 184 * @return the cloned map
universe@138 185 * @see ucx_map_copy()
universe@138 186 */
olaf@44 187 UcxMap *ucx_map_clone(UcxMap *map, copy_func fnc, void *data);
universe@138 188
universe@138 189 /**
universe@138 190 * Increases size of the hash map, if necessary.
universe@138 191 *
universe@138 192 * The load value is 0.75*UcxMap.size. If the element count exceeds the load
universe@138 193 * value, the map needs to be rehashed. Otherwise no action is performed and
universe@138 194 * this function simply returns 0.
universe@138 195 *
universe@138 196 * The rehashing process ensures, that the UcxMap.size is at least
universe@138 197 * 2.5*UcxMap.count. So there is enough room for additional elements without
universe@138 198 * the need of another soon rehashing.
universe@138 199 *
universe@138 200 * You can use this function to dramatically increase access performance.
universe@138 201 *
universe@138 202 * @param map the map to rehash
universe@138 203 * @return 1, if a memory allocation error occurred, 0 otherwise
universe@138 204 */
olaf@52 205 int ucx_map_rehash(UcxMap *map);
olaf@20 206
universe@138 207 /**
universe@138 208 * Puts a key/value-pair into the map.
universe@138 209 *
universe@138 210 * @param map the map
universe@138 211 * @param key the key
universe@138 212 * @param value the value
universe@138 213 * @return 0 on success, non-zero value on failure
universe@138 214 */
universe@138 215 int ucx_map_put(UcxMap *map, UcxKey key, void *value);
universe@138 216
universe@138 217 /**
universe@138 218 * Retrieves a value by using a key.
universe@138 219 *
universe@138 220 * @param map the map
universe@138 221 * @param key the key
universe@138 222 * @return the value
universe@138 223 */
olaf@20 224 void* ucx_map_get(UcxMap *map, UcxKey key);
universe@138 225
universe@138 226 /**
universe@138 227 * Removes a key/value-pair from the map by using the key.
universe@138 228 *
universe@138 229 * @param map the map
universe@138 230 * @param key the key
universe@138 231 * @return the removed value
universe@138 232 */
universe@53 233 void* ucx_map_remove(UcxMap *map, UcxKey key);
olaf@20 234
universe@136 235 /**
universe@136 236 * Shorthand for putting data with a sstr_t key into the map.
universe@136 237 * @param map the map
universe@136 238 * @param key the key
universe@136 239 * @param value the value
universe@138 240 * @return 0 on success, non-zero value on failure
universe@136 241 * @see ucx_map_put()
universe@136 242 */
universe@136 243 #define ucx_map_sstr_put(map, key, value) \
universe@136 244 ucx_map_put(map, ucx_key(key.ptr, key.length), (void*)value)
universe@146 245
universe@136 246 /**
universe@136 247 * Shorthand for putting data with a C string key into the map.
universe@136 248 * @param map the map
universe@136 249 * @param key the key
universe@136 250 * @param value the value
universe@138 251 * @return 0 on success, non-zero value on failure
universe@136 252 * @see ucx_map_put()
universe@136 253 */
universe@136 254 #define ucx_map_cstr_put(map, key, value) \
universe@136 255 ucx_map_put(map, ucx_key((void*)key, strlen(key)), (void*)value)
universe@146 256
universe@136 257 /**
universe@136 258 * Shorthand for putting data with an integer key into the map.
universe@136 259 * @param map the map
universe@136 260 * @param key the key
universe@136 261 * @param value the value
universe@138 262 * @return 0 on success, non-zero value on failure
universe@136 263 * @see ucx_map_put()
universe@136 264 */
universe@136 265 #define ucx_map_int_put(map, key, value) \
universe@136 266 ucx_map_put(map, ucx_key((void*)&key, sizeof(key)), (void*)value)
olaf@78 267
universe@136 268 /**
universe@136 269 * Shorthand for getting data from the map with a sstr_t key.
universe@136 270 * @param map the map
universe@136 271 * @param key the key
universe@138 272 * @return the value
universe@136 273 * @see ucx_map_get()
universe@136 274 */
universe@136 275 #define ucx_map_sstr_get(map, key) \
universe@136 276 ucx_map_get(map, ucx_key(key.ptr, key.length))
universe@146 277
universe@136 278 /**
universe@136 279 * Shorthand for getting data from the map with a C string key.
universe@138 280 * @param map the map
universe@138 281 * @param key the key
universe@138 282 * @return the value
universe@136 283 * @see ucx_map_get()
universe@136 284 */
universe@136 285 #define ucx_map_cstr_get(map, key) \
universe@136 286 ucx_map_get(map, ucx_key((void*)key, strlen(key)))
universe@146 287
universe@136 288 /**
universe@136 289 * Shorthand for getting data from the map with an integer key.
universe@136 290 * @param map the map
universe@136 291 * @param key the key
universe@138 292 * @return the value
universe@136 293 * @see ucx_map_get()
universe@136 294 */
universe@136 295 #define ucx_map_int_get(map, key) \
universe@136 296 ucx_map_get(map, ucx_key((void*)&key, sizeof(int)))
universe@146 297
universe@136 298 /**
universe@136 299 * Shorthand for removing data from the map with a sstr_t key.
universe@136 300 * @param map the map
universe@136 301 * @param key the key
universe@138 302 * @return the removed value
universe@136 303 * @see ucx_map_remove()
universe@136 304 */
universe@136 305 #define ucx_map_sstr_remove(map, key) \
universe@136 306 ucx_map_remove(map, ucx_key(key.ptr, key.length))
universe@146 307
universe@136 308 /**
universe@136 309 * Shorthand for removing data from the map with a C string key.
universe@136 310 * @param map the map
universe@136 311 * @param key the key
universe@138 312 * @return the removed value
universe@136 313 * @see ucx_map_remove()
universe@136 314 */
universe@136 315 #define ucx_map_cstr_remove(map, key) \
universe@136 316 ucx_map_remove(map, ucx_key((void*)key, strlen(key)))
universe@146 317
universe@136 318 /**
universe@136 319 * Shorthand for removing data from the map with an integer key.
universe@136 320 * @param map the map
universe@136 321 * @param key the key
universe@138 322 * @return the removed value
universe@136 323 * @see ucx_map_remove()
universe@136 324 */
universe@136 325 #define ucx_map_int_remove(map, key) \
universe@136 326 ucx_map_remove(map, ucx_key((void*)&key, sizeof(key)))
olaf@20 327
universe@138 328 /**
universe@138 329 * Creates an UcxKey based on the given data.
universe@138 330 *
universe@138 331 * This function implicitly computes the hash.
universe@138 332 *
universe@138 333 * @param data the data for the key
universe@138 334 * @param len the length of the data
universe@138 335 * @return an UcxKey with implicitly computed hash
universe@138 336 * @see ucx_hash()
universe@138 337 */
olaf@20 338 UcxKey ucx_key(void *data, size_t len);
olaf@20 339
universe@138 340 /**
universe@138 341 * Computes a murmur hash-2.
universe@138 342 *
universe@138 343 * @param data the data to hash
universe@138 344 * @param len the length of the data
universe@138 345 * @return the murmur hash-2 of the data
universe@138 346 */
universe@67 347 int ucx_hash(const char *data, size_t len);
olaf@2 348
universe@138 349 /**
universe@138 350 * Creates an iterator for a map.
universe@138 351 *
universe@138 352 * <b>Note:</b> An UcxMapIterator iterates over all elements in all element
universe@138 353 * lists successively. Therefore the order highly depends on the key hashes and
universe@138 354 * may vary under different map sizes. So generally you may <b>NOT</b> rely on
universe@138 355 * the iteration order.
universe@138 356 *
universe@138 357 * <b>Note:</b> The iterator is <b>NOT</b> initialized. You need to call
universe@138 358 * ucx_map_iter_next() at least once before accessing any information. However,
universe@138 359 * it is not recommended to access the fields of an UcxMapIterator directly.
universe@138 360 *
universe@138 361 * @param map the map to create the iterator for
universe@138 362 * @return an iterator initialized on the first element of the
universe@138 363 * first element list
universe@138 364 * @see ucx_map_iter_next()
universe@138 365 */
olaf@31 366 UcxMapIterator ucx_map_iterator(UcxMap *map);
olaf@31 367
universe@138 368 /**
universe@138 369 * Proceeds to the next element of the map (if any).
universe@138 370 *
universe@138 371 * Subsequent calls on the same iterator proceed to the next element and
universe@138 372 * store the key/value-pair into the memory specified as arguments of this
universe@138 373 * function.
universe@138 374 *
universe@138 375 * If no further elements are found, this function returns zero and leaves the
universe@138 376 * last found key/value-pair in memory.
universe@138 377 *
universe@138 378 * @param iterator the iterator to use
universe@138 379 * @param key a pointer to the memory where to store the key
universe@138 380 * @param value a pointer to the memory where to store the value
universe@138 381 * @return 1, if another element was found, 0 if all elements has been processed
universe@138 382 * @see ucx_map_iterator()
universe@138 383 */
universe@138 384 int ucx_map_iter_next(UcxMapIterator *iterator, UcxKey *key, void **value);
olaf@31 385
universe@42 386
olaf@2 387 #ifdef __cplusplus
olaf@2 388 }
olaf@2 389 #endif
olaf@2 390
olaf@120 391 #endif /* UCX_MAP_H */
olaf@2 392

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