我有一个通用列表，它 100% 有效并保持：
/**
* Generic List Container
*
* Implements a list container type.
* The list his an internal iterator for external use. For all functions
* where the state of the iterator after calling that function is not stated,
* it is undefined. That is you cannot assume anything about it.
*
* The following functions are available:
*
* listCreate - Creates a new empty list
* listDestroy - Deletes an existing list and frees all resources
* listCopy - Copies an existing list
* listGetSize - Returns the size of a given list
* listFirst - Sets the internal iterator to the first element
* in the list, and returns it.
* listInsertFirst - Inserts an element in the beginning of the list
* listInsertLast - Inserts an element in the end of the list
* listInsertBeforeCurrent - Inserts an element right before the place of
* internal iterator
* listInsertAfterCurrent - Inserts an element right after the place of the
* internal iterator
* listRemoveCurrent - Removes the element pointed by the internal
* iterator
* listGetCurrent - Return the current element (pointed by the
* internal iterator)
* listGetFirst - Sets the internal iterator (also called current
* element) to be the first element in the list and
* return it.
* listGetNext - Advances the list's iterator to the next element
* and return it
* listSort - Sorts the list according to a given criteria
* listFilter - Creates a copy of an existing list, filtered by
* a boolean predicate
* listClear - Clears all the data from the list
*/
我提供
/** Element data type for list container */
typedef void* ListElement;
/** Type of function for copying an element of the list */
typedef ListElement (*CopyListElement)(ListElement);
/** Type of function for deallocating an element of the list */
typedef void (*FreeListElement)(ListElement);
List listCreate(CopyListElement copyElement, FreeListElement freeElement);
现在，我想使用这个列表来保存指向数据的指针，而不是数据本身。例如，我想要一个类型的结构列表
struct CASH_element {
int id;
int passengers;
int unpaidPassengers;
bool reset;
int profit;
} Cash;
struct Transportation_element {
List cashes; //list of cashes
int travels;
int profit;
};
所以当我创建我使用的运输类型时：
Transportation* systemToAdd;
systemToAdd->cashes = listCreate(cashCopy, DestroyCash);
/* MORE CODE*/
现在，有趣的函数是 copyElement 函数：
void* cashCopy(void* cashCopy) {
Cash* toCopy = (Cash*) cashCopy;
if (toCopy == NULL) {
return NULL;
}
Cash* toAdd = (Cash*) malloc(sizeof(*toAdd));
if (toAdd == NULL) {
return NULL;
}
toAdd->id = toCopy->id;
toAdd->passengers=toCopy->passengers;
toAdd->unpaidPassengers = toCopy->unpaidPassengers;
toAdd->reset=toCopy->reset;
toAdd->unpaidPassengers=toCopy->unpaidPassengers;
toAdd->profit=toCopy->profit;
return (Cash*) toAdd;;
显然，这会按价值复制现金及其所有数据，一旦我独立更新现金，列表节点就不会更新。我希望它被更新。我想我必须使用指针。我试过修改函数但失败了：
void* cashCopy(void* cashCopy) {
return (Cash*)&cashCopy;
}
and adding is straightforward:
TransportationStatus trAddCash(Transportation* system, Cash c) {
if (system == NULL) {
return TR_FAIL;
}
Cash* cash=&c;
if (LIST_SUCCESS != listInsertLast(system->cashes, cash)) {
return TR_FAIL;
}
return TR_SUCCESS;
}
有一个我想要工作的代码示例：
cs1 = cashCreate(&c1, 123);
Transportation trans1;
TransportationStatus tr1;
tr1=trCreate(&trans1);
ASSERT_TEST(tr1==TR_SUCCESS);
cs1 = cashTravel(&c1, &rq1, 660, "09/08/2011-02:51"); //THE FIRST TRAVEL
tr1=trAddCash(&trans1,c1); //ADD THE CASH TO THE TRANSPORTATION STRUCT
ASSERT_TEST(tr1==TR_SUCCESS);
tr1=getTotalTravels(trans1, &result);
ASSERT_TEST(result==1); //THAT'S OKAY BECAUSE TRAVEL BEFORE COPYING
cs1 = cashTravel(&c1, &rq1, 660, "13/08/2011-02:51"); //THE SECOND TRAVEL
tr1=getTotalTravels(trans1, &result);
ASSERT_TEST(result==2); //FAIL!!!!
cashTravel(listGetFirst(trans1.cashes), &rq1, 660, "13/08/2010-02:51"); //TRAVEL WITH THE LIST NODE
tr1=getTotalTravels(trans1, &result);
ASSERT_TEST(result==2); //SUCCESS!!!!
所以基本上，我想修改我的复制功能，以便我可以独立更新节点