/* 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;
}
