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arangodb/HashIndex/hasharray.c

1227 lines
41 KiB
C
Executable File

////////////////////////////////////////////////////////////////////////////////
/// @brief hash array implementation
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2004-2012 triagens GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is triAGENS GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
/// @author Martin Schoenert
/// @author Copyright 2006-2012, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include <BasicsC/hashes.h>
#include "HashIndex/hasharray.h"
#include "HashIndex/compare.h"
// -----------------------------------------------------------------------------
// --SECTION-- HASH ARRAY
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- forward declared private functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup HashArray
/// @{
////////////////////////////////////////////////////////////////////////////////
static bool ResizeHashArray (TRI_hasharray_t*);
static bool ResizeHashArrayMulti (TRI_hasharray_t*);
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup HashArray
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief initialises an array
////////////////////////////////////////////////////////////////////////////////
bool TRI_InitHashArray (TRI_hasharray_t* array,
size_t elementSize,
uint64_t (*hashKey) (TRI_hasharray_t*, void*),
uint64_t (*hashElement) (TRI_hasharray_t*, void*),
void (*clearElement) (TRI_hasharray_t*, void*),
bool (*isEmptyElement) (TRI_hasharray_t*, void*),
bool (*isEqualKeyElement) (TRI_hasharray_t*, void*, void*),
bool (*isEqualElementElement) (TRI_hasharray_t*, void*, void*)) {
char* p;
char* e;
// ...........................................................................
// Assign the callback functions
// ...........................................................................
array->clearElement = clearElement;
array->isEmptyElement = isEmptyElement;
array->isEqualKeyElement = isEqualKeyElement;
array->isEqualElementElement = isEqualElementElement;
array->_elementSize = elementSize;
array->_nrAlloc = 10;
// ...........................................................................
// allocate storage for the hash array
// ...........................................................................
array->_table = TRI_Allocate(TRI_UNKNOWN_MEM_ZONE, array->_elementSize * array->_nrAlloc, true);
if (array->_table == NULL) {
return false;
}
// ...........................................................................
// Go through and 'zero' (clear) each item in the hash array
// ...........................................................................
p = array->_table;
e = p + array->_elementSize * array->_nrAlloc;
for (; p < e; p += array->_elementSize) {
IndexStaticClearElement(array, p);
}
array->_nrUsed = 0;
array->_nrFinds = 0;
array->_nrAdds = 0;
array->_nrRems = 0;
array->_nrResizes = 0;
array->_nrProbesF = 0;
array->_nrProbesA = 0;
array->_nrProbesD = 0;
array->_nrProbesR = 0;
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys an array, but does not free the pointer
////////////////////////////////////////////////////////////////////////////////
void TRI_DestroyHashArray (TRI_hasharray_t* array) {
char* p;
char* e;
if (array == NULL) {
return;
}
// ...........................................................................
// Go through each item in the array and remove any internal allocated memory
// ...........................................................................
p = array->_table;
e = p + array->_elementSize * array->_nrAlloc;
for (; p < e; p += array->_elementSize) {
IndexStaticDestroyElement(array, p);
}
TRI_Free(TRI_UNKNOWN_MEM_ZONE, array->_table);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys an array and frees the pointer
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeHashArray (TRI_hasharray_t* array) {
if (array != NULL) {
TRI_DestroyHashArray(array);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, array);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup Collections
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief lookups an element given a key
////////////////////////////////////////////////////////////////////////////////
void* TRI_LookupByKeyHashArray (TRI_hasharray_t* array, void* key) {
uint64_t hash;
uint64_t i;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashKey(array, key);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrFinds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualKeyElement(array, key, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesF++;
}
// ...........................................................................
// return whatever we found
// ...........................................................................
return array->_table + (i * array->_elementSize);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief finds an element given a key, return NULL if not found
////////////////////////////////////////////////////////////////////////////////
void* TRI_FindByKeyHashArray (TRI_hasharray_t* array, void* key) {
void* element;
element = TRI_LookupByKeyHashArray(array, key);
if (! IndexStaticIsEmptyElement(array, element) && IndexStaticIsEqualKeyElement(array, key, element)) {
return element;
}
return NULL;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief lookups an element given an element
////////////////////////////////////////////////////////////////////////////////
void* TRI_LookupByElementHashArray (TRI_hasharray_t* array, void* element) {
uint64_t hash;
uint64_t i;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrFinds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualElementElement(array, element, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesF++;
}
// ...........................................................................
// return whatever we found
// ...........................................................................
return (array->_table) + (i * array->_elementSize);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief finds an element given an element, returns NULL if not found
////////////////////////////////////////////////////////////////////////////////
void* TRI_FindByElementHashArray (TRI_hasharray_t* array, void* element) {
void* element2;
element2 = TRI_LookupByElementHashArray(array, element);
if (! IndexStaticIsEmptyElement(array, element2) && IndexStaticIsEqualElementElement(array, element2, element)) {
return element2;
}
return NULL;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief adds an element to the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_InsertElementHashArray (TRI_hasharray_t* array, void* element, bool overwrite) {
uint64_t hash;
uint64_t i;
bool found;
void* arrayElement;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrAdds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualElementElement(array, element, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesA++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// if we found an element, return
// ...........................................................................
found = !IndexStaticIsEmptyElement(array, arrayElement);
if (found) {
if (overwrite) {
// destroy the underlying element since we are going to stomp on top if it
IndexStaticDestroyElement(array, arrayElement);
IndexStaticCopyElementElement(array, arrayElement, element);
}
return false;
}
// ...........................................................................
// add a new element to the hash array (existing item is empty so no need to
// destroy it)
// ...........................................................................
if (! IndexStaticCopyElementElement(array, arrayElement, element)) {
return false;
}
array->_nrUsed++;
// ...........................................................................
// we are adding and the table is more than half full, extend it
// ...........................................................................
if (array->_nrAlloc < 2 * array->_nrUsed) {
if (! ResizeHashArray(array) ) {
return false;
}
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief adds an key/element to the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_InsertKeyHashArray (TRI_hasharray_t* array, void* key, void* element, bool overwrite) {
uint64_t hash;
uint64_t i;
bool found;
void* arrayElement;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashKey(array, key);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrAdds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualKeyElement(array, key, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesA++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// if we found an element, return
// ...........................................................................
found = ! IndexStaticIsEmptyElement(array, arrayElement);
if (found) {
if (overwrite) {
// destroy the underlying element since we are going to stomp on top if it
IndexStaticDestroyElement(array, arrayElement);
IndexStaticCopyElementElement(array, arrayElement, element);
}
return false;
}
// ...........................................................................
// add a new element to the associative array
// ...........................................................................
if (! IndexStaticCopyElementElement(array, arrayElement, element)) {
return false;
}
array->_nrUsed++;
// ...........................................................................
// we are adding and the table is more than half full, extend it
// ...........................................................................
if (array->_nrAlloc < 2 * array->_nrUsed) {
ResizeHashArray(array);
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes an element from the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_RemoveElementHashArray (TRI_hasharray_t* array, void* element) {
uint64_t hash;
uint64_t i;
uint64_t k;
bool found;
void* arrayElement;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrRems++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualElementElement(array, element, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesD++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// if we did not find such an item return false
// ...........................................................................
found = ! IndexStaticIsEmptyElement(array, arrayElement);
if (!found) {
return false;
}
// ...........................................................................
// remove item - destroy any internal memory associated with the element structure
// ...........................................................................
IndexStaticDestroyElement(array, arrayElement);
array->_nrUsed--;
// ...........................................................................
// and now check the following places for items to move closer together
// so that there are no gaps in the array
// ...........................................................................
k = (i + 1) % array->_nrAlloc;
while (! IndexStaticIsEmptyElement(array, array->_table + k * array->_elementSize)) {
uint64_t j = IndexStaticHashElement(array, array->_table + k * array->_elementSize) % array->_nrAlloc;
if ((i < k && !(i < j && j <= k)) || (k < i && !(i < j || j <= k))) {
// memcpy ok here since we are moving the items of the array around internally
memcpy(array->_table + i * array->_elementSize, array->_table + k * array->_elementSize, array->_elementSize);
IndexStaticClearElement(array, array->_table + k * array->_elementSize);
i = k;
}
k = (k + 1) % array->_nrAlloc;
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes an key/element to the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_RemoveKeyHashArray (TRI_hasharray_t* array, void* key) {
uint64_t hash;
uint64_t i;
uint64_t k;
bool found;
void* arrayElement;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashKey(array, key);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrRems++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualKeyElement(array, key, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesD++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// if we did not find such an item return false
// ...........................................................................
found = !IndexStaticIsEmptyElement(array, arrayElement);
if (!found) {
return false;
}
// ...........................................................................
// remove item
// ...........................................................................
IndexStaticDestroyElement(array, arrayElement);
array->_nrUsed--;
// ...........................................................................
// and now check the following places for items to move here
// ...........................................................................
k = (i + 1) % array->_nrAlloc;
while (! IndexStaticIsEmptyElement(array, array->_table + k * array->_elementSize)) {
uint64_t j = IndexStaticHashElement(array, array->_table + k * array->_elementSize) % array->_nrAlloc;
if ((i < k && !(i < j && j <= k)) || (k < i && !(i < j || j <= k))) {
// memcpy ok here since only moving items along the array internally
memcpy(array->_table + i * array->_elementSize, array->_table + k * array->_elementSize, array->_elementSize);
IndexStaticClearElement(array, array->_table + k * array->_elementSize);
i = k;
}
k = (k + 1) % array->_nrAlloc;
}
// ...........................................................................
// return success
// ...........................................................................
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- HASH ARRAY MULTI
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup Collections
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup HashArray
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief lookups an element given a key
////////////////////////////////////////////////////////////////////////////////
TRI_vector_pointer_t TRI_LookupByKeyHashArrayMulti (TRI_hasharray_t* array, void* key) {
TRI_vector_pointer_t result;
uint64_t hash;
uint64_t i;
// ...........................................................................
// initialise the vector which will hold the result if any
// ...........................................................................
TRI_InitVectorPointer(&result, TRI_UNKNOWN_MEM_ZONE);
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashKey(array, key);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrFinds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize)) {
if (IndexStaticIsEqualKeyElementMulti(array, key, array->_table + i * array->_elementSize)) {
TRI_PushBackVectorPointer(&result, array->_table + i * array->_elementSize);
}
else {
array->_nrProbesF++;
}
i = (i + 1) % array->_nrAlloc;
}
// ...........................................................................
// return whatever we found -- which could be an empty vector list if nothing
// matches.
// ...........................................................................
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief lookups an element given an element
////////////////////////////////////////////////////////////////////////////////
TRI_vector_pointer_t TRI_LookupByElementHashArrayMulti (TRI_hasharray_t* array, void* element) {
TRI_vector_pointer_t result;
uint64_t hash;
uint64_t i;
// ...........................................................................
// initialise the vector which will hold the result if any
// ...........................................................................
TRI_InitVectorPointer(&result, TRI_UNKNOWN_MEM_ZONE);
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrFinds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize)) {
if (IndexStaticIsEqualElementElementMulti(array, element, array->_table + i * array->_elementSize)) {
TRI_PushBackVectorPointer(&result, array->_table + i * array->_elementSize);
}
else {
array->_nrProbesF++;
}
i = (i + 1) % array->_nrAlloc;
}
// ...........................................................................
// return whatever we found -- which could be an empty vector list if nothing
// matches. Note that we allow multiple elements (compare with pointer impl).
// ...........................................................................
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief adds an element to the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_InsertElementHashArrayMulti (TRI_hasharray_t* array, void* element, bool overwrite) {
uint64_t hash;
uint64_t i;
bool found;
void* arrayElement;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrAdds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualElementElementMulti(array, element, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesA++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// If we found an element, return. While we allow duplicate entries in the hash
// table, we do not allow duplicate elements. Elements would refer to the
// (for example) an actual row in memory. This is different from the
// TRI_InsertElementMultiArray function below where we only have keys to
// differentiate between elements.
// ...........................................................................
found = ! IndexStaticIsEmptyElement(array, arrayElement);
if (found) {
if (overwrite) {
// destroy the underlying element since we are going to stomp on top if it
IndexStaticDestroyElement(array, arrayElement);
IndexStaticCopyElementElement(array, arrayElement, element);
}
return false;
}
// ...........................................................................
// add a new element to the associative array
// ...........................................................................
IndexStaticCopyElementElement(array, arrayElement, element);
array->_nrUsed++;
// ...........................................................................
// if we were adding and the table is more than half full, extend it
// ...........................................................................
if (array->_nrAlloc < 2 * array->_nrUsed) {
ResizeHashArrayMulti(array);
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief adds an key/element to the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_InsertKeyHashArrayMulti (TRI_hasharray_t* array, void* key, void* element, bool overwrite) {
uint64_t hash;
uint64_t i;
void* arrayElement;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashKey(array, key);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrAdds++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesA++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// We do not look for an element (as opposed to the function above). So whether
// or not there exists a duplicate we do not care.
// ...........................................................................
// ...........................................................................
// add a new element to the associative array
// ...........................................................................
IndexStaticCopyElementElement(array, arrayElement, element);
array->_nrUsed++;
// ...........................................................................
// if we were adding and the table is more than half full, extend it
// ...........................................................................
if (array->_nrAlloc < 2 * array->_nrUsed) {
ResizeHashArrayMulti(array);
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes an element from the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_RemoveElementHashArrayMulti (TRI_hasharray_t* array, void* element) {
uint64_t hash;
uint64_t i;
uint64_t k;
bool found;
void* arrayElement;
// ...........................................................................
// Obtain the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrRems++;
// ...........................................................................
// search the table
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualElementElementMulti(array, element, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesD++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// if we did not find such an item return false
// ...........................................................................
found = ! IndexStaticIsEmptyElement(array, arrayElement);
if (! found) {
return false;
}
// ...........................................................................
// remove item
// ...........................................................................
IndexStaticDestroyElement(array, arrayElement);
array->_nrUsed--;
// ...........................................................................
// and now check the following places for items to move here
// ...........................................................................
k = (i + 1) % array->_nrAlloc;
while (! IndexStaticIsEmptyElement(array, array->_table + k * array->_elementSize)) {
uint64_t j = IndexStaticHashElement(array, array->_table + k * array->_elementSize) % array->_nrAlloc;
if ((i < k && !(i < j && j <= k)) || (k < i && !(i < j || j <= k))) {
memcpy(array->_table + i * array->_elementSize, array->_table + k * array->_elementSize, array->_elementSize);
IndexStaticClearElement(array, array->_table + k * array->_elementSize);
i = k;
}
k = (k + 1) % array->_nrAlloc;
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes an key/element to the array
////////////////////////////////////////////////////////////////////////////////
bool TRI_RemoveKeyHashArrayMulti (TRI_hasharray_t* array, void* key) {
uint64_t hash;
uint64_t i;
uint64_t k;
bool found;
void* arrayElement;
// ...........................................................................
// generate hash using key
// ...........................................................................
hash = IndexStaticHashKey(array, key);
i = hash % array->_nrAlloc;
// ...........................................................................
// update statistics
// ...........................................................................
array->_nrRems++;
// ...........................................................................
// search the table -- we can only match keys
// ...........................................................................
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize) &&
! IndexStaticIsEqualKeyElementMulti(array, key, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesD++;
}
arrayElement = array->_table + (i * array->_elementSize);
// ...........................................................................
// if we did not find such an item return false
// ...........................................................................
found = ! IndexStaticIsEmptyElement(array, arrayElement);
if (! found) {
return false;
}
// ...........................................................................
// remove item
// ...........................................................................
IndexStaticDestroyElement(array, arrayElement);
array->_nrUsed--;
// ...........................................................................
// and now check the following places for items to move here
// ...........................................................................
k = (i + 1) % array->_nrAlloc;
while (! IndexStaticIsEmptyElement(array, array->_table + k * array->_elementSize)) {
uint64_t j = IndexStaticHashElement(array, array->_table + k * array->_elementSize) % array->_nrAlloc;
if ((i < k && !(i < j && j <= k)) || (k < i && !(i < j || j <= k))) {
memcpy(array->_table + i * array->_elementSize, array->_table + k * array->_elementSize, array->_elementSize);
IndexStaticClearElement(array, array->_table + k * array->_elementSize);
i = k;
}
k = (k + 1) % array->_nrAlloc;
}
return true;
}
// -----------------------------------------------------------------------------
// --SECTION-- forward declared private functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup HashArray
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief adds a new element
////////////////////////////////////////////////////////////////////////////////
static void AddNewElement (TRI_hasharray_t* array, void* element) {
uint64_t hash;
uint64_t i;
// ...........................................................................
// compute the hash
// ...........................................................................
hash = IndexStaticHashElement(array, element);
// ...........................................................................
// search the table
// ...........................................................................
i = hash % array->_nrAlloc;
while (! IndexStaticIsEmptyElement(array, array->_table + i * array->_elementSize)) {
i = (i + 1) % array->_nrAlloc;
array->_nrProbesR++;
}
// ...........................................................................
// add a new element to the associative array
// memcpy ok here since are simply moving array items internally
// ...........................................................................
memcpy(array->_table + i * array->_elementSize, element, array->_elementSize);
array->_nrUsed++;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief resizes the array
////////////////////////////////////////////////////////////////////////////////
static bool ResizeHashArray (TRI_hasharray_t* array) {
char * oldTable;
uint64_t oldAlloc;
uint64_t j;
oldTable = array->_table;
oldAlloc = array->_nrAlloc;
array->_nrAlloc = 2 * array->_nrAlloc + 1;
array->_nrUsed = 0;
array->_nrResizes++;
array->_table = TRI_Allocate(TRI_UNKNOWN_MEM_ZONE, array->_nrAlloc * array->_elementSize, true);
if (array->_table == NULL) {
array->_table = oldTable;
return false;
}
for (j = 0; j < array->_nrAlloc; j++) {
IndexStaticClearElement(array, array->_table + j * array->_elementSize);
}
for (j = 0; j < oldAlloc; j++) {
if (! IndexStaticIsEmptyElement(array, oldTable + j * array->_elementSize)) {
AddNewElement(array, oldTable + j * array->_elementSize);
}
}
TRI_Free(TRI_UNKNOWN_MEM_ZONE, oldTable);
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief resizes the array
////////////////////////////////////////////////////////////////////////////////
static bool ResizeHashArrayMulti (TRI_hasharray_t* array) {
char* oldTable;
uint64_t oldAlloc;
uint64_t j;
oldTable = array->_table;
oldAlloc = array->_nrAlloc;
array->_nrAlloc = 2 * array->_nrAlloc + 1;
array->_nrUsed = 0;
array->_nrResizes++;
array->_table = TRI_Allocate(TRI_UNKNOWN_MEM_ZONE, array->_nrAlloc * array->_elementSize, true);
if (array->_table == NULL) {
array->_table = oldTable;
return false;
}
for (j = 0; j < array->_nrAlloc; j++) {
IndexStaticClearElement(array, array->_table + j * array->_elementSize);
}
for (j = 0; j < oldAlloc; j++) {
if (! IndexStaticIsEmptyElement(array, oldTable + j * array->_elementSize)) {
AddNewElement(array, oldTable + j * array->_elementSize);
}
}
TRI_Free(TRI_UNKNOWN_MEM_ZONE, oldTable);
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
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