int
listObserverAttach(LIST_OBSERVER_T *observer, LIST_T *list)
{
int cc;
if (! list->allowObservers) {
listerrno = (int) LIST_ERR_NOOBSVR;
return -1;
}
cc = listInsertEntryBefore(list->observers,
(LIST_ENTRY_T *)list->observers,
(LIST_ENTRY_T *)observer);
if (cc < 0)
return cc;
observer->list = list;
return 0;
}
/* listInsertEntryAtBack()
*
* before:
*
* L->1->2->3
*
* after:
*
* L->1->2->3->4
*
*/
int
listInsertEntryAtBack(LIST_T * list, LIST_ENTRY_T *entry)
{
return listInsertEntryBefore(list, (LIST_ENTRY_T *)list, entry);
}
/* listInsertEntryAtFront()
*
* Push items in from of the list:
*
* before:
*
* L->3->2->1
*
* after:
*
* L->4->3->2->1
*
*/
int
listInsertEntryAtFront(LIST_T * list, LIST_ENTRY_T *entry)
{
return listInsertEntryBefore(list, list->forw, entry);
}
int
listInsertEntryAfter(LIST_T * list, LIST_ENTRY_T *pred, LIST_ENTRY_T *entry)
{
return listInsertEntryBefore(list, pred->forw, entry);
}
