From f1025bbf3292c8c199e23e618c062ec1e9f2f055 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Thu, 9 Jan 2014 10:59:16 +0100 Subject: [PATCH] list: add list_first_entry_or_null() Signed-off-by: Sascha Hauer --- include/linux/list.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/include/linux/list.h b/include/linux/list.h index 5ae90b43a..bc63ece95 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -291,6 +291,17 @@ static inline void list_splice_init(struct list_head *list, #define list_last_entry(head, type, member) \ list_entry((head)->prev, type, member) +/** + * list_first_entry_or_null - get the first element from a list + * @ptr: the list head to take the element from. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_struct within the struct. + * + * Note that if the list is empty, it returns NULL. + */ +#define list_first_entry_or_null(ptr, type, member) \ + (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) + /** * list_for_each - iterate over a list * @pos: the &struct list_head to use as a loop cursor.