/* 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 *sqlite3HashInsert(Hash *pH, const void *pKey, int nKey, void *data){ int hraw; /* Raw hash value of the key */ int h; /* the hash of the key modulo hash table size */ HashElem *elem; /* Used to loop thru the element list */ HashElem *new_elem; /* New element added to the pH */ assert( pH!=0 ); hraw = strHash(pKey, nKey); if( pH->htsize ){ h = hraw % pH->htsize; elem = findElementGivenHash(pH,pKey,nKey,h); if( elem ){ void *old_data = elem->data; if( data==0 ){ removeElementGivenHash(pH,elem,h); }else{ elem->data = data; if( !pH->copyKey ){ elem->pKey = (void *)pKey; } assert(nKey==elem->nKey); } return old_data; } } if( data==0 ) return 0; new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) ); if( new_elem==0 ) return data; if( pH->copyKey && pKey!=0 ){ new_elem->pKey = sqlite3Malloc( nKey ); if( new_elem->pKey==0 ){ sqlite3_free(new_elem); return data; } memcpy((void*)new_elem->pKey, pKey, nKey); }else{ new_elem->pKey = (void*)pKey; } new_elem->nKey = nKey; pH->count++; if( pH->htsize==0 ){ rehash(pH, 128/sizeof(pH->ht[0])); if( pH->htsize==0 ){ pH->count = 0; if( pH->copyKey ){ sqlite3_free(new_elem->pKey); } sqlite3_free(new_elem); return data; } } if( pH->count > pH->htsize ){ rehash(pH,pH->htsize*2); } assert( pH->htsize>0 ); h = hraw % pH->htsize; insertElement(pH, &pH->ht[h], new_elem); new_elem->data = data; return 0; }
/* Insert an element into the hash table pH. The key is pKey ** and the data is "data". ** ** If no element exists with a matching key, then a new ** element is created and 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 *sqlite3HashInsert(Hash *pH, const char *pKey, void *data) { unsigned int h; /* the hash of the key modulo hash table size */ HashElem *elem; /* Used to loop thru the element list */ HashElem *new_elem; /* New element added to the pH */ assert( pH!=0 ); assert( pKey!=0 ); elem = findElementWithHash(pH,pKey,&h); if( elem ) { void *old_data = elem->data; if( data==0 ) { removeElementGivenHash(pH,elem,h); } else { elem->data = data; elem->pKey = pKey; } return old_data; } if( data==0 ) return 0; new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) ); if( new_elem==0 ) return data; new_elem->pKey = pKey; new_elem->data = data; pH->count++; if( pH->count>=10 && pH->count > 2*pH->htsize ) { if( rehash(pH, pH->count*2) ) { assert( pH->htsize>0 ); h = strHash(pKey) % pH->htsize; } } insertElement(pH, pH->ht ? &pH->ht[h] : 0, new_elem); return 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 * HashInsert( Hash *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 */ HashElem *elem; /* Used to loop thru the element list */ HashElem *new_elem; /* New element added to the pH */ assert( pH!=0 ); hraw = binHash(pKey, nKey); assert( (pH->htsize & (pH->htsize-1))==0 ); h = hraw & (pH->htsize-1); elem = findElementGivenHash(pH,pKey,nKey,h); if( elem ){ void *old_data = elem->data; if( data==0 ){ removeElementGivenHash(pH,elem,h); }else{ elem->data = data; } return old_data; } if( data==0 ) return 0; new_elem = (HashElem*)pH->xMalloc( sizeof(HashElem) ); if( new_elem==0 ) return data; if( pH->copyKey && pKey!=0 ){ new_elem->pKey = pH->xMalloc( nKey ); if( new_elem->pKey==0 ){ pH->xFree(new_elem); return data; } memcpy((void*)new_elem->pKey, pKey, nKey); }else{ new_elem->pKey = (void*)pKey; } new_elem->nKey = nKey; pH->count++; if( pH->htsize==0 ){ rehash(pH,8); if( pH->htsize==0 ){ pH->count = 0; pH->xFree(new_elem); return data; } } if( pH->count > pH->htsize ){ rehash(pH,pH->htsize*2); } assert( pH->htsize>0 ); assert( (pH->htsize & (pH->htsize-1))==0 ); h = hraw & (pH->htsize-1); insertElement(pH, &pH->ht[h], new_elem); new_elem->data = data; return 0; }
void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, void *data){ unsigned int h; /* the hash of the key modulo hash table size */ HashElem *elem; /* Used to loop thru the element list */ HashElem *new_elem; /* New element added to the pH */ assert( pH!=0 ); assert( pKey!=0 ); assert( nKey>=0 ); if( pH->htsize ){ h = strHash(pKey, nKey) % pH->htsize;/*如果pH的htsize成员变量不为0,即使用哈希表存放数据项那么使用 strHash 函数计算桶号h*/ }else{ h = 0;/*如果pH的htsize成员变量为0,那么h=0*/ } elem = findElementGivenHash(pH,pKey,nKey,h); if( elem ){ void *old_data = elem->data; if( data==0 ){ removeElementGivenHash(pH,elem,h); }else{ elem->data = data; elem->pKey = pKey; assert(nKey==elem->nKey); } return old_data; } if( data==0 ) return 0; new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) ); if( new_elem==0 ) return data; new_elem->pKey = pKey; new_elem->nKey = nKey; new_elem->data = data; pH->count++; if( pH->count>=10 && pH->count > 2*pH->htsize ){ if( rehash(pH, pH->count*2) ){ assert( pH->htsize>0 ); h = strHash(pKey, nKey) % pH->htsize; } } if( pH->ht ){ insertElement(pH, &pH->ht[h], new_elem); }else{ insertElement(pH, 0, new_elem); } return 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 and 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 *systemHashInsert(Hash *pH, const char *pKey, int nKey, void *data) { unsigned int h; // the hash of the key modulo hash table size HashElement *element; // Used to loop thru the element list HashElement *newElement; // New element added to the pH assert(pH != 0); assert(pKey != 0); assert(nKey >= 0); h = (pH->Table ? strHash(pKey, nKey) % pH->TableSize : 0); element = findElementGivenHash(pH, pKey, nKey, h); if (element) { void *lastData = element->Data; if (data == 0) removeElementGivenHash(pH, element, h); else { element->Data = data; element->pKey = pKey; assert(nKey == elem->nKey); } return lastData; } if (data == 0) return 0; newElement = (HashElement*)systemMalloc(sizeof(HashElement)); if (newElement == 0) return data; newElement->pKey = pKey; newElement->nKey = nKey; newElement->Data = data; pH->Count++; if ((pH->Count >= 10) && pH->Count > (2*pH->TableSize)) if (rehash(pH, pH->Count*2)) { assert(pH->TableSize > 0); h = strHash(pKey, nKey) % pH->TableSize; } if (pH->Table) insertElement(pH, &pH->Table[h], newElement); else insertElement(pH, 0, newElement); return 0; }