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annotate PrivateHash.c @ 32:bd376656f8ab

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author Nina Engelhardt <nengel@mailbox.tu-berlin.de>
date Wed, 24 Apr 2013 16:35:19 +0200
parents 18a72865dd78
children
rev   line source
Me@14 1 /*
Me@14 2 * Copyright 2009 OpenSourceStewardshipFoundation.org
Me@14 3 * Licensed under GNU General Public License version 2
Me@14 4 *
Me@14 5 *
Me@14 6 * Author: seanhalle@yahoo.com
Me@14 7 */
Me@14 8
Me@14 9 #include "PrivateHash.h"
Me@14 10
Me@14 11
seanhalle@23 12 HashTable *
Me@14 13 makeHashTable( int numHashSlots, FreeEntryContentFnPtr freeFn )
Me@14 14 { HashTable * retTable;
Me@17 15 retTable = VMS_int__malloc( sizeof( HashTable ) );
Me@14 16
Me@14 17 retTable->freeEntryContentFn = freeFn;
Me@14 18
Me@17 19 retTable->entries = VMS_int__malloc( numHashSlots * sizeof(HashEntry *) );
Me@14 20 retTable->numEntries = 0;
Me@14 21 retTable->tableSz = numHashSlots;
Me@14 22
Me@14 23 nullOutTablesArray( retTable );
Me@14 24
Me@14 25 return retTable;
Me@14 26 }
Me@14 27
seanhalle@23 28 HashTable *
seanhalle@23 29 makeHashTable_WL( int numHashSlots, FreeEntryContentFnPtr freeFn )
seanhalle@23 30 { HashTable * retTable;
seanhalle@23 31 retTable = VMS_WL__malloc( sizeof( HashTable ) );
seanhalle@23 32
seanhalle@23 33 retTable->freeEntryContentFn = freeFn;
seanhalle@23 34
seanhalle@23 35 retTable->entries = VMS_int__malloc( numHashSlots * sizeof(HashEntry *) );
seanhalle@23 36 retTable->numEntries = 0;
seanhalle@23 37 retTable->tableSz = numHashSlots;
seanhalle@23 38
seanhalle@23 39 nullOutTablesArray( retTable );
seanhalle@23 40
seanhalle@23 41 return retTable;
seanhalle@23 42 }
seanhalle@23 43
seanhalle@23 44 void
Me@14 45 doubleTableSize( HashTable *table )
nengel@28 46 { printf("***This code is broken; program will probably segfault soon***\n");
nengel@28 47
nengel@28 48 int i, oldTableSz, newTableSz;
Me@14 49 HashEntry *entry, *nextEntry, **oldEntries, **newEntries;
Me@14 50
Me@14 51 oldTableSz = table->tableSz;
Me@14 52 oldEntries = table->entries;
Me@14 53
seanhalle@23 54 newTableSz = 2 * oldTableSz;
Me@17 55 newEntries = VMS_int__malloc( newTableSz * sizeof(HashEntry *) );
Me@14 56
Me@14 57 table->tableSz = newTableSz;
Me@14 58 table->entries = newEntries;
Me@14 59 table->numEntries = 0; //about to add them all back!
Me@14 60
Me@14 61 // move all the entries from old to new
Me@14 62 for( i=0; i < oldTableSz; i++ )
Me@14 63 { if( oldEntries[i] != NULL )
Me@14 64 { entry = oldEntries[i];
Me@14 65 while( entry != NULL )
seanhalle@23 66 { nextEntry = entry->next; //save for later
Me@14 67 entry->next = NULL;
Me@14 68 putEntryIntoTable( entry, table ); //does not allocate anything
Me@14 69 entry = nextEntry;
Me@14 70 }
Me@14 71 }
Me@14 72 }
Me@14 73 }
Me@14 74
Me@14 75 void
Me@14 76 nullOutTablesArray( HashTable *table )
Me@14 77 { int i, tableSz;
Me@14 78 tableSz = table->tableSz;
Me@14 79 HashEntry ** entries = table->entries;
Me@14 80 for( i = 0; i < tableSz; i++ )
Me@14 81 entries[ i ] = NULL;
Me@14 82 }
Me@14 83
Me@14 84 unsigned int
Me@14 85 hashThisKey( char* s, int hashSz )
Me@14 86 { unsigned int h = 0;
Me@14 87 unsigned int i;
Me@14 88 hashkey_t* key = (hashkey_t*)s;
Me@14 89
Me@14 90 for(i=0 ; i<sizeof(hashkey_t); i++ )
Me@14 91 h = key->hashable[i] + h*31;
Me@14 92 return h % hashSz;
Me@14 93 }
Me@14 94
seanhalle@23 95 /*Copies the string that is the key*/
nengel@26 96 HashEntry *
seanhalle@23 97 makeHashEntry( char * key )
seanhalle@23 98 { HashEntry *hashEntry;
seanhalle@23 99
seanhalle@23 100 int32 len = strlen(key);
seanhalle@23 101
seanhalle@23 102 hashEntry = (HashEntry*) VMS_int__malloc( sizeof( HashEntry ) );
seanhalle@23 103 if( hashEntry == NULL ) return NULL;
seanhalle@23 104
seanhalle@23 105 hashEntry->key = VMS_int__malloc( len + 1 );
seanhalle@23 106 if( hashEntry->key == NULL ) return NULL;
seanhalle@23 107 memcpy( hashEntry->key, key, len + 1 );
seanhalle@23 108 hashEntry->next = NULL;
seanhalle@23 109
seanhalle@23 110 return hashEntry;
seanhalle@23 111 }
seanhalle@23 112
seanhalle@23 113
Me@14 114 /*Need this to be separated out, for use in both getParam and putParam
Me@14 115 */
Me@14 116 HashEntry *
Me@14 117 getEntryFromTable( char *key, HashTable * table )
seanhalle@23 118 { uint32
Me@14 119 hashIndex = hashThisKey( key, table->tableSz );
Me@14 120 HashEntry*
Me@14 121 hashEntry = table->entries[ hashIndex ];
Me@14 122 for( ; hashEntry != NULL; hashEntry = hashEntry->next )
Me@14 123 {
seanhalle@23 124 if( strcmp( hashEntry->key, key ) == 0 )
Me@14 125 return hashEntry;
Me@14 126 }
Me@14 127 return NULL;
Me@14 128 }
Me@14 129
Me@14 130 void *
Me@14 131 getValueFromTable( char *key, HashTable * table )
Me@14 132 { HashEntry *entry;
Me@14 133 entry = getEntryFromTable( key, table );
Me@14 134 if( entry == NULL ) return NULL;
Me@14 135
Me@14 136 return entry->content;
Me@14 137 }
Me@14 138
Me@14 139 /*If key already has a value, clobber the old one and replace it
Me@14 140 */
Me@14 141 int
Me@14 142 addValueIntoTable( char* key, void *content, HashTable *table )
Me@14 143 { unsigned int hashIdx;
Me@14 144 HashEntry* hashEntry;
Me@14 145
Me@14 146 hashEntry = getEntryFromTable( key, table );
Me@14 147 if( hashEntry == NULL )
Me@14 148 { hashIdx = hashThisKey( key, table->tableSz );
seanhalle@23 149 hashEntry = makeHashEntry( key );
Me@14 150 hashEntry->next = (table->entries)[hashIdx];
Me@14 151 (table->entries)[hashIdx] = hashEntry;
Me@14 152 table->numEntries += 1;
Me@14 153 if( table->tableSz < table->numEntries ) doubleTableSize( table );
Me@14 154 }
Me@14 155 else
Me@14 156 { (*(table->freeEntryContentFn))( hashEntry->content );
Me@14 157 }
Me@14 158 hashEntry->content = content;
Me@14 159 return 1;
Me@14 160 }
Me@14 161
seanhalle@23 162
Me@14 163 int
Me@14 164 putEntryIntoTable( HashEntry *entry, HashTable *table )
Me@14 165 { unsigned int hashIdx;
Me@14 166 HashEntry* testEntry;
Me@14 167
Me@14 168 testEntry = getEntryFromTable( entry->key, table );
Me@14 169 if( testEntry == NULL )
Me@14 170 { hashIdx = hashThisKey( entry->key, table->tableSz );
Me@14 171 entry->next = (table->entries)[hashIdx];
Me@14 172 (table->entries)[hashIdx] = entry;
Me@14 173 table->numEntries += 1;
Me@14 174 if( table->tableSz < table->numEntries ) doubleTableSize( table );
Me@14 175 }
Me@14 176 else
Me@14 177 { (*(table->freeEntryContentFn))( testEntry->content );
seanhalle@23 178 //being lazy -- will create bug in code that relies on having ptr
seanhalle@23 179 // to elem given to insert into table!
Me@14 180 testEntry->content = entry->content;
Me@14 181 entry->content = NULL;
Me@14 182 freeHashEntryButNotContent( entry );
Me@14 183 }
Me@14 184 return 1;
Me@14 185 }
Me@14 186
Me@14 187 /*Better version
Me@14 188 */
Me@14 189 void
Me@14 190 untested_putEntryIntoTable( HashEntry *entry, HashTable * table )
Me@14 191 { HashEntry *testEntry, *prevEntry = NULL;
Me@14 192 unsigned int
Me@14 193 hashIndex = hashThisKey( entry->key, table->tableSz );
Me@14 194
Me@14 195 testEntry = table->entries[ hashIndex ];
Me@14 196 for( ; testEntry != NULL; testEntry = testEntry->next )
seanhalle@23 197 { if( strcmp( testEntry->key, entry->key ) == 0 )
Me@14 198 { if( prevEntry == NULL )
Me@14 199 { table->entries[hashIndex] = entry;
Me@14 200 entry->next = testEntry->next;
Me@14 201 }
Me@14 202 else
Me@14 203 { prevEntry->next = entry;
Me@14 204 entry->next = testEntry->next;
Me@14 205 }
Me@14 206 freeHashEntryUsing( testEntry, table ); //frees content too!
Me@14 207 return;
Me@14 208 }
Me@14 209 }
Me@14 210 //wasn't found, so insert
Me@14 211 entry->next = table->entries[hashIndex];
Me@14 212 table->entries[hashIndex] = entry;
Me@14 213 }
Me@14 214
Me@14 215
seanhalle@23 216 bool8
Me@14 217 deleteEntryFromTable( char *key, HashTable *table )
Me@14 218 { HashEntry *hashEntry;
seanhalle@23 219 HashEntry **addrOfPrevPtr;
Me@14 220 unsigned int hashIndex;
Me@14 221
Me@14 222 hashIndex = hashThisKey( key, table->tableSz );
seanhalle@23 223 addrOfPrevPtr = &( table->entries[ hashIndex ] );//for removing node
seanhalle@23 224 hashEntry = *addrOfPrevPtr; //already did work, might as well use it
Me@14 225 while( hashEntry != NULL )
seanhalle@23 226 { if( strcmp( hashEntry->key, key ) == 0 )
Me@14 227 {
seanhalle@23 228 *addrOfPrevPtr = hashEntry->next; //remove node from list
Me@14 229 //TODO: Free the contents of entry?
Me@14 230 freeHashEntryButNotContent( hashEntry );
Me@14 231 table->numEntries -= 1;
Me@14 232 return TRUE;
Me@14 233 }
seanhalle@23 234 addrOfPrevPtr = &( hashEntry->next );
seanhalle@23 235 hashEntry = *addrOfPrevPtr;
Me@14 236 }
Me@14 237 return FALSE;
Me@14 238 }
Me@14 239
Me@14 240 void
Me@14 241 freeHashTable( HashTable *table )
Me@14 242 { int i;
Me@14 243 HashEntry *hashEntry, *temp, **entries;
Me@14 244
Me@14 245 entries = table->entries;
Me@14 246 for( i=0; i < table->tableSz; i++ )
Me@14 247 { if( entries[i] != NULL )
Me@14 248 { hashEntry = entries[i];
Me@14 249 while( hashEntry != NULL )
Me@14 250 {
Me@14 251 temp = hashEntry->next;
Me@14 252 freeHashEntryUsing( hashEntry, table );
Me@14 253 hashEntry = temp;
Me@14 254 }
Me@14 255 }
Me@14 256 }
nengel@28 257 VMS_WL__free( entries );
nengel@28 258 VMS_WL__free( table );
Me@14 259 }
Me@14 260
Me@14 261 void
Me@14 262 freeHashEntryUsing( HashEntry *entry, HashTable *table )
Me@14 263 {
Me@14 264 if( entry->content != NULL )
Me@14 265 (*(table->freeEntryContentFn))( entry->content );
seanhalle@21 266 VMS_int__free( entry->key ); //was VMS_int__malloc'd above, so free it
Me@17 267 VMS_int__free( entry );
Me@14 268 }
Me@14 269
Me@14 270 void
seanhalle@23 271 freeHashEntryUsing_WL( HashEntry *entry, HashTable *table )
seanhalle@23 272 {
seanhalle@23 273 if( entry->content != NULL )
seanhalle@23 274 (*(table->freeEntryContentFn))( entry->content );
seanhalle@23 275 VMS_WL__free( entry->key ); //was VMS_int__malloc'd above, so free it
seanhalle@23 276 VMS_WL__free( entry );
seanhalle@23 277 }
seanhalle@23 278
seanhalle@23 279 void
seanhalle@23 280 freeHashTable_WL( HashTable *table )
seanhalle@23 281 { int i;
seanhalle@23 282 HashEntry *hashEntry, *temp, **entries;
seanhalle@23 283
seanhalle@23 284 entries = table->entries;
seanhalle@23 285 for( i=0; i < table->tableSz; i++ )
seanhalle@23 286 { if( entries[i] != NULL )
seanhalle@23 287 { hashEntry = entries[i];
seanhalle@23 288 while( hashEntry != NULL )
seanhalle@23 289 {
seanhalle@23 290 temp = hashEntry->next;
seanhalle@23 291 freeHashEntryUsing_WL( hashEntry, table );
seanhalle@23 292 hashEntry = temp;
seanhalle@23 293 }
seanhalle@23 294 }
seanhalle@23 295 }
seanhalle@23 296 }
seanhalle@23 297
seanhalle@23 298
seanhalle@23 299 void
Me@14 300 freeHashEntryButNotContent( HashEntry *entry )
Me@14 301 {
seanhalle@21 302 VMS_int__free( entry->key ); //was VMS_int__malloc'd above, so free it
Me@17 303 VMS_int__free( entry );
Me@14 304 }
Me@14 305
seanhalle@23 306 void
seanhalle@23 307 freeHashEntryButNotContent_WL( HashEntry *entry )
seanhalle@23 308 {
seanhalle@23 309 VMS_WL__free( entry->key ); //was VMS_int__malloc'd above, so free it
seanhalle@23 310 VMS_WL__free( entry );
seanhalle@23 311 }
seanhalle@23 312
seanhalle@23 313
seanhalle@23 314
seanhalle@23 315
seanhalle@23 316 //======================= 32 bit integer key version ======================
seanhalle@23 317
seanhalle@23 318 /*key is array of uint32, with first entry being the num ints in key.
seanhalle@23 319 * that means size of key is content of first entry times 4, plus the
seanhalle@23 320 * size of first entry itself, which is another 4*/
seanhalle@23 321 #define sizeOfKey(key) key[0]*4 + 4
seanhalle@23 322
seanhalle@23 323
seanhalle@23 324 HashTable *
seanhalle@23 325 makeHashTable32( int powerOf2OfSz, FreeEntryContentFnPtr freeFn )
seanhalle@23 326 { HashTable * retTable;
seanhalle@23 327 int32 numHashSlots;
seanhalle@23 328
seanhalle@23 329 retTable = VMS_int__malloc( sizeof( HashTable ) );
seanhalle@23 330
seanhalle@23 331 numHashSlots = 1 << powerOf2OfSz;
nengel@32 332 retTable->hashMask = 0xffffffff >> (32 - powerOf2OfSz);
seanhalle@23 333 retTable->prevHash = (int32)rand();
seanhalle@23 334
seanhalle@23 335 retTable->freeEntryContentFn = freeFn;
seanhalle@23 336
seanhalle@23 337 retTable->entries = VMS_int__malloc( numHashSlots * sizeof(HashEntry *));
seanhalle@23 338 retTable->numEntries = 0;
seanhalle@23 339 retTable->tableSz = numHashSlots;
seanhalle@23 340
seanhalle@23 341 nullOutTablesArray( retTable );
seanhalle@23 342
seanhalle@23 343 return retTable;
seanhalle@23 344 }
seanhalle@23 345
seanhalle@23 346 HashTable *
seanhalle@23 347 makeDefaultSizeHashTable32( FreeEntryContentFnPtr freeFn )
seanhalle@23 348 {
seanhalle@23 349 return makeHashTable32( DEFAULT_POWER_OF_2_TABLE_SIZE, freeFn );
seanhalle@23 350 }
seanhalle@23 351
seanhalle@23 352 HashEntry *
seanhalle@23 353 makeHashEntry32( uint32 * key )
seanhalle@23 354 { HashEntry *hashEntry;
seanhalle@23 355
seanhalle@23 356 hashEntry = (HashEntry*) VMS_int__malloc( sizeof( HashEntry ) );
seanhalle@23 357 if( hashEntry == NULL ) return NULL;
seanhalle@23 358 hashEntry->key = VMS_int__malloc( sizeOfKey(key) );
seanhalle@23 359 if( hashEntry->key == NULL ) return NULL;
seanhalle@23 360 memcpy( hashEntry->key, key, sizeOfKey(key) );
seanhalle@23 361 hashEntry->next = NULL;
seanhalle@23 362
seanhalle@23 363 return hashEntry;
seanhalle@23 364 }
seanhalle@23 365
seanhalle@23 366
seanhalle@23 367
seanhalle@23 368 int32
seanhalle@23 369 putEntryIntoTable32( HashEntry *entry, HashTable *table )
seanhalle@23 370 { unsigned int hashIdx;
seanhalle@23 371 HashEntry* testEntry;
seanhalle@23 372
seanhalle@23 373 testEntry = getEntryFromTable32( (uint32 *)entry->key, table );
seanhalle@23 374 if( testEntry == NULL ) //no entry w/key, so add passed-in as list-head
nengel@32 375 { hashIdx = hashThisKey32( (uint32 *)entry->key, table );
seanhalle@23 376 entry->next = (table->entries)[hashIdx];
seanhalle@23 377 (table->entries)[hashIdx] = entry;
seanhalle@23 378 table->numEntries += 1;
seanhalle@23 379 //keep num entries less than half the num indexes in table
seanhalle@23 380 if( table->numEntries > (table->tableSz >>1) ) doubleTableSize(table);
seanhalle@23 381 }
seanhalle@23 382 else //entry w/key already exists, so free content, then replace then
seanhalle@23 383 // free the passed-in entry, leaving the entry already in table
seanhalle@23 384 { (*(table->freeEntryContentFn))( testEntry->content );
seanhalle@23 385 //being lazy -- will create bug in code that relies on having ptr
seanhalle@23 386 // to elem given to insert into table!
seanhalle@23 387 testEntry->content = entry->content;
seanhalle@23 388 entry->content = NULL;
seanhalle@23 389 freeHashEntryButNotContent( entry );
seanhalle@23 390 }
seanhalle@23 391 return 1;
seanhalle@23 392 }
seanhalle@23 393
seanhalle@23 394
seanhalle@23 395 void
seanhalle@23 396 doubleTableSize32( HashTable *table )
seanhalle@23 397 { int i, oldTableSz, newTableSz;
seanhalle@23 398 HashEntry *entry, *nextEntry, **oldEntries, **newEntries;
seanhalle@23 399
seanhalle@23 400 oldTableSz = table->tableSz;
seanhalle@23 401 oldEntries = table->entries;
seanhalle@23 402
seanhalle@23 403 newTableSz = 2 * oldTableSz;
seanhalle@23 404 newEntries = VMS_int__malloc( newTableSz * sizeof(HashEntry *) );
seanhalle@23 405
seanhalle@23 406 table->tableSz = newTableSz;
seanhalle@23 407 table->entries = newEntries;
seanhalle@23 408 table->numEntries = 0; //about to add them all back!
seanhalle@23 409
seanhalle@23 410 // move all the entries from old to new
seanhalle@23 411 for( i=0; i < oldTableSz; i++ )
seanhalle@23 412 { if( oldEntries[i] != NULL )
seanhalle@23 413 { entry = oldEntries[i];
seanhalle@23 414 while( entry != NULL )
seanhalle@23 415 { nextEntry = entry->next; //save for later
seanhalle@23 416 entry->next = NULL; //null before, so can chain in new
seanhalle@23 417 putEntryIntoTable32( entry, table ); //doesn't allocate anything
seanhalle@23 418 entry = nextEntry;
seanhalle@23 419 }
seanhalle@23 420 }
seanhalle@23 421 }
seanhalle@23 422 }
seanhalle@23 423
seanhalle@23 424 /*The key is a self-sized array of 32 bit unsigned ints, with the first
seanhalle@23 425 * entry being the number of ints in the key, which makes up the rest of
seanhalle@23 426 * the array.*/
seanhalle@23 427 int32
seanhalle@23 428 hashThisKey32( uint32 *key, HashTable *hashTable )
seanhalle@23 429 { int32 hashOfKey;
seanhalle@23 430
seanhalle@23 431 //the hash function takes addr of start of key array, plus num int32s,
seanhalle@23 432 hashOfKey = jenkHash32( &key[1], *key );
seanhalle@23 433 hashTable->prevHash = hashOfKey;
seanhalle@23 434
seanhalle@23 435 /*The hash is a full 32 bits, but only want hashes that fall within
seanhalle@23 436 * the size of the table. So, mask off the higher bits. */
seanhalle@23 437 return ( hashTable->hashMask & hashOfKey ); //reduce to size of table
seanhalle@23 438 }
seanhalle@23 439
seanhalle@23 440
seanhalle@23 441 /*The first entry of key says the size of the key, while key itself is the
seanhalle@23 442 * rest of the integers in the array
seanhalle@23 443 */
seanhalle@23 444 HashEntry *
seanhalle@23 445 getEntryFromTable32( uint32 *key, HashTable * table )
seanhalle@23 446 { unsigned int
seanhalle@23 447 hashIndex = hashThisKey32( key, table );
seanhalle@23 448 HashEntry*
seanhalle@23 449 hashEntry = table->entries[ hashIndex ];
seanhalle@23 450 for( ; hashEntry != NULL; hashEntry = hashEntry->next )
seanhalle@23 451 {
seanhalle@23 452 if( memcmp( hashEntry->key, key, sizeOfKey(key) ) == 0 )
seanhalle@23 453 return hashEntry;
seanhalle@23 454 }
seanhalle@23 455 return NULL;
seanhalle@23 456 }
seanhalle@23 457
seanhalle@23 458 void *
seanhalle@23 459 getValueFromTable32( uint32 *key, HashTable * table )
seanhalle@23 460 { HashEntry *entry;
seanhalle@23 461 entry = getEntryFromTable32( key, table );
seanhalle@23 462 if( entry == NULL ) return NULL;
seanhalle@23 463
seanhalle@23 464 return entry->content;
seanhalle@23 465 }
seanhalle@23 466
seanhalle@24 467 /*Returns NULL if failed to insert, else returns ptr to hash entry
seanhalle@24 468 * NOTE: does a copy of the key, so key can be alloc'd on stack */
seanhalle@23 469 HashEntry *
seanhalle@23 470 addValueIntoTable32( uint32* key, void *content, HashTable *table )
seanhalle@23 471 { unsigned int hashIdx;
seanhalle@23 472 HashEntry* hashEntry;
seanhalle@23 473
seanhalle@23 474 hashEntry = getEntryFromTable32( key, table );
seanhalle@23 475 if( hashEntry == NULL )
seanhalle@23 476 { hashIdx = hashThisKey32( key, table );
seanhalle@23 477 hashEntry = makeHashEntry32( key );
seanhalle@23 478 hashEntry->next = (table->entries)[hashIdx];
seanhalle@23 479 (table->entries)[hashIdx] = hashEntry;
seanhalle@23 480 table->numEntries += 1;
seanhalle@23 481 //Check if need to make bigger -- keep half-full (hence ">> 1")
seanhalle@23 482 if( table->numEntries > table->tableSz >>1 ) doubleTableSize( table );
seanhalle@23 483 }
seanhalle@23 484 else
seanhalle@23 485 { (*(table->freeEntryContentFn))( hashEntry->content );
seanhalle@23 486 }
seanhalle@23 487 hashEntry->content = content;
seanhalle@23 488 return hashEntry;
seanhalle@23 489 }
seanhalle@23 490
seanhalle@23 491
seanhalle@23 492 bool32
seanhalle@23 493 deleteEntryFromTable32( uint32 *key, HashTable *table )
seanhalle@23 494 { HashEntry *hashEntry;
seanhalle@23 495 HashEntry **addrOfPrevPtr;
seanhalle@23 496 unsigned int hashIndex;
seanhalle@23 497
seanhalle@23 498 hashIndex = hashThisKey32( key, table );
seanhalle@23 499 hashEntry = table->entries[ hashIndex ];
seanhalle@23 500 //go down the chained list, checking all with this hash value
seanhalle@23 501 addrOfPrevPtr = &( table->entries[hashIndex] ); //for removing a node
seanhalle@23 502 hashEntry = *addrOfPrevPtr; //did ptr chasing, might as well use it
seanhalle@23 503 while( hashEntry != NULL )
seanhalle@23 504 { if( memcmp( hashEntry->key, key, sizeOfKey(key) ) == 0 )
seanhalle@23 505 { *addrOfPrevPtr = hashEntry->next; //remove node from list
seanhalle@23 506 freeHashEntryButNotContent( hashEntry );
seanhalle@23 507 table->numEntries -= 1;
seanhalle@23 508 return TRUE;
seanhalle@23 509 }
seanhalle@23 510 addrOfPrevPtr = &(hashEntry->next); //chg content of *this* to remove
seanhalle@23 511 hashEntry = *addrOfPrevPtr; //cheaper than hashEntry->next
seanhalle@23 512 }
seanhalle@23 513 return FALSE;
seanhalle@23 514 }
seanhalle@23 515