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diff --git a/src/libtracker-fts/fts3_hash.c b/src/libtracker-fts/fts3_hash.c
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-/*
-** 2001 September 22
-**
-** The author disclaims copyright to this source code. In place of
-** a legal notice, here is a blessing:
-**
-** May you do good and not evil.
-** May you find forgiveness for yourself and forgive others.
-** May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the implementation of generic hash-tables used in SQLite.
-** We've modified it slightly to serve as a standalone hash table
-** implementation for the full-text indexing module.
-*/
-
-/*
-** The code in this file is only compiled if:
-**
-** * The FTS3 module is being built as an extension
-** (in which case SQLITE_CORE is not defined), or
-**
-** * The FTS3 module is being built into the core of
-** SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
-*/
-#include "fts3Int.h"
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "fts3_hash.h"
-
-/*
-** Malloc and Free functions
-*/
-static void *fts3HashMalloc(int n){
- void *p = sqlite3_malloc(n);
- if( p ){
- memset(p, 0, n);
- }
- return p;
-}
-static void fts3HashFree(void *p){
- sqlite3_free(p);
-}
-
-/* Turn bulk memory into a hash table object by initializing the
-** fields of the Hash structure.
-**
-** "pNew" is a pointer to the hash table that is to be initialized.
-** keyClass is one of the constants
-** FTS3_HASH_BINARY or FTS3_HASH_STRING. The value of keyClass
-** determines what kind of key the hash table will use. "copyKey" is
-** true if the hash table should make its own private copy of keys and
-** false if it should just use the supplied pointer.
-*/
-void sqlite3Fts3HashInit(Fts3Hash *pNew, char keyClass, char copyKey){
- assert( pNew!=0 );
- assert( keyClass>=FTS3_HASH_STRING && keyClass<=FTS3_HASH_BINARY );
- pNew->keyClass = keyClass;
- pNew->copyKey = copyKey;
- pNew->first = 0;
- pNew->count = 0;
- pNew->htsize = 0;
- pNew->ht = 0;
-}
-
-/* Remove all entries from a hash table. Reclaim all memory.
-** Call this routine to delete a hash table or to reset a hash table
-** to the empty state.
-*/
-void sqlite3Fts3HashClear(Fts3Hash *pH){
- Fts3HashElem *elem; /* For looping over all elements of the table */
-
- assert( pH!=0 );
- elem = pH->first;
- pH->first = 0;
- fts3HashFree(pH->ht);
- pH->ht = 0;
- pH->htsize = 0;
- while( elem ){
- Fts3HashElem *next_elem = elem->next;
- if( pH->copyKey && elem->pKey ){
- fts3HashFree(elem->pKey);
- }
- fts3HashFree(elem);
- elem = next_elem;
- }
- pH->count = 0;
-}
-
-/*
-** Hash and comparison functions when the mode is FTS3_HASH_STRING
-*/
-static int fts3StrHash(const void *pKey, int nKey){
- const char *z = (const char *)pKey;
- int h = 0;
- if( nKey<=0 ) nKey = (int) strlen(z);
- while( nKey > 0 ){
- h = (h<<3) ^ h ^ *z++;
- nKey--;
- }
- return h & 0x7fffffff;
-}
-static int fts3StrCompare(const void *pKey1, int n1, const void *pKey2, int n2){
- if( n1!=n2 ) return 1;
- return strncmp((const char*)pKey1,(const char*)pKey2,n1);
-}
-
-/*
-** Hash and comparison functions when the mode is FTS3_HASH_BINARY
-*/
-static int fts3BinHash(const void *pKey, int nKey){
- int h = 0;
- const char *z = (const char *)pKey;
- while( nKey-- > 0 ){
- h = (h<<3) ^ h ^ *(z++);
- }
- return h & 0x7fffffff;
-}
-static int fts3BinCompare(const void *pKey1, int n1, const void *pKey2, int n2){
- if( n1!=n2 ) return 1;
- return memcmp(pKey1,pKey2,n1);
-}
-
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** The C syntax in this function definition may be unfamilar to some
-** programmers, so we provide the following additional explanation:
-**
-** The name of the function is "ftsHashFunction". The function takes a
-** single parameter "keyClass". The return value of ftsHashFunction()
-** is a pointer to another function. Specifically, the return value
-** of ftsHashFunction() is a pointer to a function that takes two parameters
-** with types "const void*" and "int" and returns an "int".
-*/
-static int (*ftsHashFunction(int keyClass))(const void*,int){
- if( keyClass==FTS3_HASH_STRING ){
- return &fts3StrHash;
- }else{
- assert( keyClass==FTS3_HASH_BINARY );
- return &fts3BinHash;
- }
-}
-
-/*
-** Return a pointer to the appropriate hash function given the key class.
-**
-** For help in interpreted the obscure C code in the function definition,
-** see the header comment on the previous function.
-*/
-static int (*ftsCompareFunction(int keyClass))(const void*,int,const void*,int){
- if( keyClass==FTS3_HASH_STRING ){
- return &fts3StrCompare;
- }else{
- assert( keyClass==FTS3_HASH_BINARY );
- return &fts3BinCompare;
- }
-}
-
-/* Link an element into the hash table
-*/
-static void fts3HashInsertElement(
- Fts3Hash *pH, /* The complete hash table */
- struct _fts3ht *pEntry, /* The entry into which pNew is inserted */
- Fts3HashElem *pNew /* The element to be inserted */
-){
- Fts3HashElem *pHead; /* First element already in pEntry */
- pHead = pEntry->chain;
- if( pHead ){
- pNew->next = pHead;
- pNew->prev = pHead->prev;
- if( pHead->prev ){ pHead->prev->next = pNew; }
- else { pH->first = pNew; }
- pHead->prev = pNew;
- }else{
- pNew->next = pH->first;
- if( pH->first ){ pH->first->prev = pNew; }
- pNew->prev = 0;
- pH->first = pNew;
- }
- pEntry->count++;
- pEntry->chain = pNew;
-}
-
-
-/* Resize the hash table so that it cantains "new_size" buckets.
-** "new_size" must be a power of 2. The hash table might fail
-** to resize if sqliteMalloc() fails.
-**
-** Return non-zero if a memory allocation error occurs.
-*/
-static int fts3Rehash(Fts3Hash *pH, int new_size){
- struct _fts3ht *new_ht; /* The new hash table */
- Fts3HashElem *elem, *next_elem; /* For looping over existing elements */
- int (*xHash)(const void*,int); /* The hash function */
-
- assert( (new_size & (new_size-1))==0 );
- new_ht = (struct _fts3ht *)fts3HashMalloc( new_size*sizeof(struct _fts3ht) );
- if( new_ht==0 ) return 1;
- fts3HashFree(pH->ht);
- pH->ht = new_ht;
- pH->htsize = new_size;
- xHash = ftsHashFunction(pH->keyClass);
- for(elem=pH->first, pH->first=0; elem; elem = next_elem){
- int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
- next_elem = elem->next;
- fts3HashInsertElement(pH, &new_ht[h], elem);
- }
- return 0;
-}
-
-/* This function (for internal use only) locates an element in an
-** hash table that matches the given key. The hash for this key has
-** already been computed and is passed as the 4th parameter.
-*/
-static Fts3HashElem *fts3FindElementByHash(
- const Fts3Hash *pH, /* The pH to be searched */
- const void *pKey, /* The key we are searching for */
- int nKey,
- int h /* The hash for this key. */
-){
- Fts3HashElem *elem; /* Used to loop thru the element list */
- int count; /* Number of elements left to test */
- int (*xCompare)(const void*,int,const void*,int); /* comparison function */
-
- if( pH->ht ){
- struct _fts3ht *pEntry = &pH->ht[h];
- elem = pEntry->chain;
- count = pEntry->count;
- xCompare = ftsCompareFunction(pH->keyClass);
- while( count-- && elem ){
- if( (*xCompare)(elem->pKey,elem->nKey,pKey,nKey)==0 ){
- return elem;
- }
- elem = elem->next;
- }
- }
- return 0;
-}
-
-/* Remove a single entry from the hash table given a pointer to that
-** element and a hash on the element's key.
-*/
-static void fts3RemoveElementByHash(
- Fts3Hash *pH, /* The pH containing "elem" */
- Fts3HashElem* elem, /* The element to be removed from the pH */
- int h /* Hash value for the element */
-){
- struct _fts3ht *pEntry;
- if( elem->prev ){
- elem->prev->next = elem->next;
- }else{
- pH->first = elem->next;
- }
- if( elem->next ){
- elem->next->prev = elem->prev;
- }
- pEntry = &pH->ht[h];
- if( pEntry->chain==elem ){
- pEntry->chain = elem->next;
- }
- pEntry->count--;
- if( pEntry->count<=0 ){
- pEntry->chain = 0;
- }
- if( pH->copyKey && elem->pKey ){
- fts3HashFree(elem->pKey);
- }
- fts3HashFree( elem );
- pH->count--;
- if( pH->count<=0 ){
- assert( pH->first==0 );
- assert( pH->count==0 );
- fts3HashClear(pH);
- }
-}
-
-Fts3HashElem *sqlite3Fts3HashFindElem(
- const Fts3Hash *pH,
- const void *pKey,
- int nKey
-){
- int h; /* A hash on key */
- int (*xHash)(const void*,int); /* The hash function */
-
- if( pH==0 || pH->ht==0 ) return 0;
- xHash = ftsHashFunction(pH->keyClass);
- assert( xHash!=0 );
- h = (*xHash)(pKey,nKey);
- assert( (pH->htsize & (pH->htsize-1))==0 );
- return fts3FindElementByHash(pH,pKey,nKey, h & (pH->htsize-1));
-}
-
-/*
-** Attempt to locate an element of the hash table pH with a key
-** that matches pKey,nKey. Return the data for this element if it is
-** found, or NULL if there is no match.
-*/
-void *sqlite3Fts3HashFind(const Fts3Hash *pH, const void *pKey, int nKey){
- Fts3HashElem *pElem; /* The element that matches key (if any) */
-
- pElem = sqlite3Fts3HashFindElem(pH, pKey, nKey);
- return pElem ? pElem->data : 0;
-}
-
-/* Insert an element into the hash table pH. The key is pKey,nKey
-** and the data is "data".
-**
-** If no element exists with a matching key, then a new
-** element is created. A copy of the key is made if the copyKey
-** flag is set. NULL is returned.
-**
-** If another element already exists with the same key, then the
-** new data replaces the old data and the old data is returned.
-** The key is not copied in this instance. If a malloc fails, then
-** the new data is returned and the hash table is unchanged.
-**
-** If the "data" parameter to this function is NULL, then the
-** element corresponding to "key" is removed from the hash table.
-*/
-void *sqlite3Fts3HashInsert(
- Fts3Hash *pH, /* The hash table to insert into */
- const void *pKey, /* The key */
- int nKey, /* Number of bytes in the key */
- void *data /* The data */
-){
- int hraw; /* Raw hash value of the key */
- int h; /* the hash of the key modulo hash table size */
- Fts3HashElem *elem; /* Used to loop thru the element list */
- Fts3HashElem *new_elem; /* New element added to the pH */
- int (*xHash)(const void*,int); /* The hash function */
-
- assert( pH!=0 );
- xHash = ftsHashFunction(pH->keyClass);
- assert( xHash!=0 );
- hraw = (*xHash)(pKey, nKey);
- assert( (pH->htsize & (pH->htsize-1))==0 );
- h = hraw & (pH->htsize-1);
- elem = fts3FindElementByHash(pH,pKey,nKey,h);
- if( elem ){
- void *old_data = elem->data;
- if( data==0 ){
- fts3RemoveElementByHash(pH,elem,h);
- }else{
- elem->data = data;
- }
- return old_data;
- }
- if( data==0 ) return 0;
- if( (pH->htsize==0 && fts3Rehash(pH,8))
- || (pH->count>=pH->htsize && fts3Rehash(pH, pH->htsize*2))
- ){
- pH->count = 0;
- return data;
- }
- assert( pH->htsize>0 );
- new_elem = (Fts3HashElem*)fts3HashMalloc( sizeof(Fts3HashElem) );
- if( new_elem==0 ) return data;
- if( pH->copyKey && pKey!=0 ){
- new_elem->pKey = fts3HashMalloc( nKey );
- if( new_elem->pKey==0 ){
- fts3HashFree(new_elem);
- return data;
- }
- memcpy((void*)new_elem->pKey, pKey, nKey);
- }else{
- new_elem->pKey = (void*)pKey;
- }
- new_elem->nKey = nKey;
- pH->count++;
- assert( pH->htsize>0 );
- assert( (pH->htsize & (pH->htsize-1))==0 );
- h = hraw & (pH->htsize-1);
- fts3HashInsertElement(pH, &pH->ht[h], new_elem);
- new_elem->data = data;
- return 0;
-}
-
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
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