Implementing ex32 List copy, split, and join

lcthw-remnants-2/liblcthw/src/lcthw/list.c

@@ -129,7 +129,7 @@ void *List_remove(List *list, ListNode *node)
     list->first->prev = NULL;
   } else if(node == list->last) {
     list->last = node->prev;
-    check(list->last != NULL, "INvalid list, somehow got a next that is NULL.");
+    check(list->last != NULL, "Invalid list, somehow got a next that is NULL.");
     list->last->next = NULL;
   } else {
     ListNode *after = node->next;
@@ -145,3 +145,68 @@ void *List_remove(List *list, ListNode *node)
 error:
   return result;
 }
+
+
+List *List_copy(List *list)
+{
+  List_validate(list);
+
+  List *out = List_create();
+  LIST_FOREACH(list, first, next, cur) {
+    List_push(out, cur->value);
+  }
+
+  return out;
+}
+
+
+int List_split(List *list, void *split, List *a, List *b)
+{
+  List_validate(list);
+
+  check(list->first && list->last, "List is empty.");
+  check(split, "split can't be NULL");
+
+  if(split == list->last->value || (split == list->first->value && split == list->last->value)) {
+    (*a) = *List_copy(list);
+    return 0;
+  } else if(split == list->first->value) {
+    (*b) = *List_copy(list);
+    List_push(a, List_shift(b));
+    return 0;
+  } else {
+    int past_split = 0;
+    LIST_FOREACH(list, first, next, cur) {
+      if(past_split) {
+        List_push(b, cur->value);
+        continue;
+      }
+
+      if(cur->value == split) {
+        past_split = 1;
+      }
+
+      List_push(a, cur->value);
+    }
+  }
+
+  return 0;
+
+error:
+  return -1;
+}
+
+
+void List_join(List *list, List *b)
+{
+  List_validate(list);
+  List_validate(b);
+
+  List *tail = List_copy(b);
+
+  list->last->next = tail->first;
+  list->count += tail->count;
+  free(tail);
+
+  return;
+}

lcthw-remnants-2/liblcthw/src/lcthw/list.h

@@ -35,6 +35,10 @@ void *List_shift(List *list);
 
 void *List_remove(List *list, ListNode *node);
 
+List *List_copy(List *list);
+int List_split(List *list, void *split, List *a, List *b);
+void List_join(List *list, List *b);
+
 #define List_validate(A) (assert(A != NULL && List_count(A) > -1 &&\
       (List_count(A) > 0 && List_first(A) != NULL) && "invalid *List"))