int DListInsert_Prev(DList *list, DListElmt *element, const void *data)
{
DListElmt *element_new;
if (element == NULL &&
DListSize(list) != 0)
{
return -1;
}
if ((element_new = (DListElmt*)malloc(sizeof(DListElmt))) == NULL)
{
return -1;
}
element_new->data = (void*)data;
if (DListSize(list) == 0)
{
list->Head = element_new;
list->Head->prev = NULL;
list->Head->next = NULL;
list->Tail = element_new;
}
else
{
element_new->next = element;
element_new->prev = element->prev;
if (element->prev == NULL)
{
list->Head = element_new;
}
else
{
element->prev->next = element;
}
element->prev = element_new;
}
list->nSize++;
return 0;
}
void DListDestory(DList *list)
{
void *data;
while (0 < DListSize(list))
{
if (DListRemove(list, DListTail(list), (void**)&data) == 0 &&
list->destory != NULL)
{
list->destory(data);
}
}
memset(list, 0, sizeof(DList));
return;
}
int DListRemove(DList *list, DListElmt *element, void **data)
{
if (element == NULL || DListSize(list) == 0)
{
return -1;
}
*data = element->data;
if (element == list->Head)
{
list->Head = element->next;
if (list->Head == NULL)
{
list->Tail = NULL;
}
else
{
element->next->prev = NULL;
}
}
else
{
element->prev->next = element->next;
if (element->next == NULL)
{
list->Tail = element->prev;
}
else
{
element->next->prev = element->prev;
}
}
free(element);
list->nSize--;
return 0;
}
/* Checks if the list is empty. If true returns 1, else - returns 0. */
int DListIsEmpty(const dlist_t *dlist)
{
return(DListSize(dlist) == 0);
}