15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 2001 September 22 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** The author disclaims copyright to this source code. In place of 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** a legal notice, here is a blessing: 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** May you do good and not evil. 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** May you find forgiveness for yourself and forgive others. 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** May you share freely, never taking more than you give. 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)************************************************************************* 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** This is the implementation of generic hash-tables used in SQLite. 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** We've modified it slightly to serve as a standalone hash table 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** implementation for the full-text indexing module. 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <assert.h> 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <stdlib.h> 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <string.h> 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** The code in this file is only compiled if: 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** * The FTS1 module is being built as an extension 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** (in which case SQLITE_CORE is not defined), or 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** * The FTS1 module is being built into the core of 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** SQLite (in which case SQLITE_ENABLE_FTS1 is defined). 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1) 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "fts1_hash.h" 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static void *malloc_and_zero(int n){ 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void *p = malloc(n); 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( p ){ 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) memset(p, 0, n); 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return p; 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Turn bulk memory into a hash table object by initializing the 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** fields of the Hash structure. 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** "pNew" is a pointer to the hash table that is to be initialized. 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** keyClass is one of the constants 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** FTS1_HASH_BINARY or FTS1_HASH_STRING. The value of keyClass 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** determines what kind of key the hash table will use. "copyKey" is 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** true if the hash table should make its own private copy of keys and 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** false if it should just use the supplied pointer. 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void sqlite3Fts1HashInit(fts1Hash *pNew, int keyClass, int copyKey){ 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( pNew!=0 ); 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( keyClass>=FTS1_HASH_STRING && keyClass<=FTS1_HASH_BINARY ); 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->keyClass = keyClass; 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->copyKey = copyKey; 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->first = 0; 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->count = 0; 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->htsize = 0; 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->ht = 0; 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->xMalloc = malloc_and_zero; 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->xFree = free; 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Remove all entries from a hash table. Reclaim all memory. 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** Call this routine to delete a hash table or to reset a hash table 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** to the empty state. 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void sqlite3Fts1HashClear(fts1Hash *pH){ 705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *elem; /* For looping over all elements of the table */ 715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( pH!=0 ); 735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem = pH->first; 745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->first = 0; 755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->ht ) pH->xFree(pH->ht); 765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->ht = 0; 775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->htsize = 0; 785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while( elem ){ 795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *next_elem = elem->next; 805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->copyKey && elem->pKey ){ 815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->xFree(elem->pKey); 825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->xFree(elem); 845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem = next_elem; 855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->count = 0; 875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** Hash and comparison functions when the mode is FTS1_HASH_STRING 915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int strHash(const void *pKey, int nKey){ 935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const char *z = (const char *)pKey; 945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h = 0; 955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( nKey<=0 ) nKey = (int) strlen(z); 965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while( nKey > 0 ){ 975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) h = (h<<3) ^ h ^ *z++; 985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) nKey--; 995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1005821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return h & 0x7fffffff; 1015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int strCompare(const void *pKey1, int n1, const void *pKey2, int n2){ 1035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( n1!=n2 ) return 1; 1045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return strncmp((const char*)pKey1,(const char*)pKey2,n1); 1055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 1085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** Hash and comparison functions when the mode is FTS1_HASH_BINARY 1095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 1105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int binHash(const void *pKey, int nKey){ 1115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h = 0; 1125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const char *z = (const char *)pKey; 1135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while( nKey-- > 0 ){ 1145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) h = (h<<3) ^ h ^ *(z++); 1155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return h & 0x7fffffff; 1175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int binCompare(const void *pKey1, int n1, const void *pKey2, int n2){ 1195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( n1!=n2 ) return 1; 1205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return memcmp(pKey1,pKey2,n1); 1215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 1245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** Return a pointer to the appropriate hash function given the key class. 1255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 1265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** The C syntax in this function definition may be unfamilar to some 1275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** programmers, so we provide the following additional explanation: 1285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 1295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** The name of the function is "hashFunction". The function takes a 1305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** single parameter "keyClass". The return value of hashFunction() 1315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** is a pointer to another function. Specifically, the return value 1325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** of hashFunction() is a pointer to a function that takes two parameters 1335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** with types "const void*" and "int" and returns an "int". 1345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 1355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int (*hashFunction(int keyClass))(const void*,int){ 1365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( keyClass==FTS1_HASH_STRING ){ 1375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return &strHash; 1385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }else{ 1395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( keyClass==FTS1_HASH_BINARY ); 1405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return &binHash; 1415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* 1455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** Return a pointer to the appropriate hash function given the key class. 1465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 1475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** For help in interpreted the obscure C code in the function definition, 1485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** see the header comment on the previous function. 1495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 1505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static int (*compareFunction(int keyClass))(const void*,int,const void*,int){ 1515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( keyClass==FTS1_HASH_STRING ){ 1525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return &strCompare; 1535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }else{ 1545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( keyClass==FTS1_HASH_BINARY ); 1555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return &binCompare; 1565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Link an element into the hash table 1605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 1615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static void insertElement( 1625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1Hash *pH, /* The complete hash table */ 1635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct _fts1ht *pEntry, /* The entry into which pNew is inserted */ 1645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *pNew /* The element to be inserted */ 1655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)){ 1665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *pHead; /* First element already in pEntry */ 1675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pHead = pEntry->chain; 1685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pHead ){ 1695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->next = pHead; 1705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->prev = pHead->prev; 1715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pHead->prev ){ pHead->prev->next = pNew; } 1725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) else { pH->first = pNew; } 1735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pHead->prev = pNew; 1745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }else{ 1755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->next = pH->first; 1765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->first ){ pH->first->prev = pNew; } 1775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pNew->prev = 0; 1785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->first = pNew; 1795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pEntry->count++; 1815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pEntry->chain = pNew; 1825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Resize the hash table so that it cantains "new_size" buckets. 1865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** "new_size" must be a power of 2. The hash table might fail 1875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** to resize if sqliteMalloc() fails. 1885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 1895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static void rehash(fts1Hash *pH, int new_size){ 1905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct _fts1ht *new_ht; /* The new hash table */ 1915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *elem, *next_elem; /* For looping over existing elements */ 1925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int (*xHash)(const void*,int); /* The hash function */ 1935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( (new_size & (new_size-1))==0 ); 1955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) new_ht = (struct _fts1ht *)pH->xMalloc( new_size*sizeof(struct _fts1ht) ); 1965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( new_ht==0 ) return; 1975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->ht ) pH->xFree(pH->ht); 1985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->ht = new_ht; 1995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->htsize = new_size; 2005821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) xHash = hashFunction(pH->keyClass); 2015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for(elem=pH->first, pH->first=0; elem; elem = next_elem){ 2025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1); 2035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) next_elem = elem->next; 2045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) insertElement(pH, &new_ht[h], elem); 2055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* This function (for internal use only) locates an element in an 2095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** hash table that matches the given key. The hash for this key has 2105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** already been computed and is passed as the 4th parameter. 2115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 2125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static fts1HashElem *findElementGivenHash( 2135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const fts1Hash *pH, /* The pH to be searched */ 2145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const void *pKey, /* The key we are searching for */ 2155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int nKey, 2165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h /* The hash for this key. */ 2175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)){ 2185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *elem; /* Used to loop thru the element list */ 2195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int count; /* Number of elements left to test */ 2205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int (*xCompare)(const void*,int,const void*,int); /* comparison function */ 2215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->ht ){ 2235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct _fts1ht *pEntry = &pH->ht[h]; 2245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem = pEntry->chain; 2255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) count = pEntry->count; 2265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) xCompare = compareFunction(pH->keyClass); 2275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while( count-- && elem ){ 2285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 2295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return elem; 2305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem = elem->next; 2325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return 0; 2355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Remove a single entry from the hash table given a pointer to that 2385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** element and a hash on the element's key. 2395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 2405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static void removeElementGivenHash( 2415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1Hash *pH, /* The pH containing "elem" */ 2425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem* elem, /* The element to be removed from the pH */ 2435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h /* Hash value for the element */ 2445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)){ 2455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct _fts1ht *pEntry; 2465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( elem->prev ){ 2475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem->prev->next = elem->next; 2485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }else{ 2495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->first = elem->next; 2505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( elem->next ){ 2525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem->next->prev = elem->prev; 2535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pEntry = &pH->ht[h]; 2555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pEntry->chain==elem ){ 2565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pEntry->chain = elem->next; 2575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pEntry->count--; 2595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pEntry->count<=0 ){ 2605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pEntry->chain = 0; 2615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->copyKey && elem->pKey ){ 2635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->xFree(elem->pKey); 2645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->xFree( elem ); 2665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->count--; 2675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->count<=0 ){ 2685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( pH->first==0 ); 2695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( pH->count==0 ); 2705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashClear(pH); 2715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Attempt to locate an element of the hash table pH with a key 2755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** that matches pKey,nKey. Return the data for this element if it is 2765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** found, or NULL if there is no match. 2775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 2785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void *sqlite3Fts1HashFind(const fts1Hash *pH, const void *pKey, int nKey){ 2795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h; /* A hash on key */ 2805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *elem; /* The element that matches key */ 2815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int (*xHash)(const void*,int); /* The hash function */ 2825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH==0 || pH->ht==0 ) return 0; 2845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) xHash = hashFunction(pH->keyClass); 2855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( xHash!=0 ); 2865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) h = (*xHash)(pKey,nKey); 2875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( (pH->htsize & (pH->htsize-1))==0 ); 2885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem = findElementGivenHash(pH,pKey,nKey, h & (pH->htsize-1)); 2895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return elem ? elem->data : 0; 2905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Insert an element into the hash table pH. The key is pKey,nKey 2935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** and the data is "data". 2945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 2955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** If no element exists with a matching key, then a new 2965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** element is created. A copy of the key is made if the copyKey 2975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** flag is set. NULL is returned. 2985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 2995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** If another element already exists with the same key, then the 3005821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** new data replaces the old data and the old data is returned. 3015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** The key is not copied in this instance. If a malloc fails, then 3025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** the new data is returned and the hash table is unchanged. 3035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** 3045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** If the "data" parameter to this function is NULL, then the 3055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)** element corresponding to "key" is removed from the hash table. 3065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)*/ 3075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void *sqlite3Fts1HashInsert( 3085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1Hash *pH, /* The hash table to insert into */ 3095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const void *pKey, /* The key */ 3105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int nKey, /* Number of bytes in the key */ 3115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void *data /* The data */ 3125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)){ 3135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int hraw; /* Raw hash value of the key */ 3145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int h; /* the hash of the key modulo hash table size */ 3155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *elem; /* Used to loop thru the element list */ 3165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) fts1HashElem *new_elem; /* New element added to the pH */ 3175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int (*xHash)(const void*,int); /* The hash function */ 3185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( pH!=0 ); 3205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) xHash = hashFunction(pH->keyClass); 3215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( xHash!=0 ); 3225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) hraw = (*xHash)(pKey, nKey); 3235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( (pH->htsize & (pH->htsize-1))==0 ); 3245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) h = hraw & (pH->htsize-1); 3255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem = findElementGivenHash(pH,pKey,nKey,h); 3265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( elem ){ 3275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void *old_data = elem->data; 3285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( data==0 ){ 3295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) removeElementGivenHash(pH,elem,h); 3305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }else{ 3315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) elem->data = data; 3325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return old_data; 3345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( data==0 ) return 0; 3365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) new_elem = (fts1HashElem*)pH->xMalloc( sizeof(fts1HashElem) ); 3375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( new_elem==0 ) return data; 3385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->copyKey && pKey!=0 ){ 3395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) new_elem->pKey = pH->xMalloc( nKey ); 3405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( new_elem->pKey==0 ){ 3415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->xFree(new_elem); 3425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return data; 3435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) memcpy((void*)new_elem->pKey, pKey, nKey); 3455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }else{ 3465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) new_elem->pKey = (void*)pKey; 3475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) new_elem->nKey = nKey; 3495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->count++; 3505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->htsize==0 ){ 3515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) rehash(pH,8); 3525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->htsize==0 ){ 3535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->count = 0; 3545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) pH->xFree(new_elem); 3555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return data; 3565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if( pH->count > pH->htsize ){ 3595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) rehash(pH,pH->htsize*2); 3605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( pH->htsize>0 ); 3625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) assert( (pH->htsize & (pH->htsize-1))==0 ); 3635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) h = hraw & (pH->htsize-1); 3645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) insertElement(pH, &pH->ht[h], new_elem); 3655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) new_elem->data = data; 3665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return 0; 3675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1) */ 370