alist: Add a way to get the next element
Add a new function which returns the next element after the one
provided, if it exists in the list.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/alist.c b/lib/alist.c
index b7928ca..7730fe0 100644
--- a/lib/alist.c
+++ b/lib/alist.c
@@ -106,6 +106,27 @@
return lst->data + index * lst->obj_size;
}
+int alist_calc_index(const struct alist *lst, const void *ptr)
+{
+ uint index;
+
+ if (!lst->count || ptr < lst->data)
+ return -1;
+
+ index = (ptr - lst->data) / lst->obj_size;
+
+ return index;
+}
+
+const void *alist_next_ptrd(const struct alist *lst, const void *ptr)
+{
+ int index = alist_calc_index(lst, ptr);
+
+ assert(index != -1);
+
+ return alist_get_ptr(lst, index + 1);
+}
+
void *alist_ensure_ptr(struct alist *lst, uint index)
{
uint minsize = index + 1;