Making a generic ArrayLIst in C

Question

I am trying to implement a java like arraylist in C and now I am trying to make it generic. I am new to C and pointer arithmetic but I triedusing void* pointer for container, th

Answer 1

It looks like you're pretty close, but there were some issues with your add function.

Since list is a pointer you need list->numElements not list.numElements and the same for list->elementSize. Also since you are only inserting one element, the third argument to memcpy should just be list->elementSize.

void add(ArrayList *list, void *input) {
    if (list->numElements >= list->conSize) {
        resize(list);
        printf("resized\n");
    }
    memcpy((char*)list->con + list->numElements * list->elementSize, input, list->elementSize);
    list->numElements++;
}

The resize function looks almost correct, except that if realloc fails it just returns. It should probably either error out or return a value indicating an error to the caller.