What is the problem with mapPut ? I cannot find the problem - c

Question

map contains - returns whether or not a key exists inside the map.
mapPut - Gives a specific key a given value and adding it to the map by order, if the key exists, the value is overridden.
mapRemove - Removes a pair of (key, data) elements for which the key matches a given element (by the key compare function).
mapGetFirst - Sets the internal iterator to the first key in the map, and returns it.
MapKeyElement mapGetFirst(Map map){
if(map == NULL){
return NULL;
}
if (map->head == NULL){
return NULL;
}
map->iterator = map->head;
return (map->copyMapKeyElements(map->iterator->key));
}
mapGetNext - Advances the internal iterator to the next key and
returns it.
MapKeyElement mapGetNext(Map map){
if(map == NULL){
return NULL;
}
if((map->iterator->next)== NULL) {
return NULL;
}
map->iterator = map->iterator->next;
return (map->copyMapKeyElements(map->iterator->key));
}
typedef struct MapElements_t{
MapDataElement data;
MapKeyElement key;
struct MapElements_t* next;
} *MapElements;
struct Map_t{
copyMapDataElements copyMapDataElements;
copyMapKeyElements copyMapKeyElements;
freeMapDataElements freeMapDataElements;
freeMapKeyElements freeMapKeyElements;
compareMapKeyElements compareMapKeyElements;
MapElements head;
MapElements iterator;
};
/* ...... */
MapResult mapPut(Map map, MapKeyElement keyElement, MapDataElement dataElement) {
if ((map == NULL) || (keyElement == NULL) || (dataElement == NULL)) {
return MAP_NULL_ARGUMENT;
}
if (mapContains(map, keyElement)) {
mapRemove(map, keyElement);
}
MapElements new_map_element = malloc(sizeof(new_map_element));
if (new_map_element == NULL) {
return MAP_OUT_OF_MEMORY;
}
new_map_element->data = dataElement;
new_map_element->key = keyElement;
new_map_element->next = NULL;
if(map->head == NULL){
map->head = new_map_element;
map->iterator = map->head;
return MAP_SUCCESS;
}
mapGetFirst(map);
if (map->compareMapKeyElements(keyElement, map->iterator->key) < 0){
new_map_element->next = map->iterator;
map->head = new_map_element;
return MAP_SUCCESS;
}
while(map->iterator->next != NULL) {
if (map->compareMapKeyElements(keyElement, map->iterator->next->key) < 0) {
new_map_element->next = map->iterator->next;
map->iterator = new_map_element;
return MAP_SUCCESS;
}
mapGetNext(map);
}
map->iterator->next = new_map_element;
return MAP_SUCCESS;
}

Answer 1

You have typedefs that include a pointer, such as typedef struct MapElements_t{...} *MapElements; which makes the type MapElements a pointer.
This is discouraged and for the following reason:
When you do
MapElements new_map_element = malloc(sizeof(new_map_element));
you are allocating the size of a pointer, not the size of the thing pointed to. In your case you should do:
MapElements new_map_element = malloc(sizeof(*new_map_element));
but preferably you would do:
typedef struct MapElements_t
{
//...
struct MapElements_t* next;
} MapElements;
so you make a variable that is a pointer to the thing have explicitly the *.
MapElements *new_map_element = malloc(sizeof(*new_map_element));

Answer 2

The fault was here; I have to replace this code:
new_map_element->data = dataElement;
new_map_element->key = keyElement;
with this code:
new_map_element->data = map->copyMapDataElements(dataElement);
new_map_element->key = map->copyMapKeyElements(keyElement);