Commit 99602572 authored Apr 28, 2008 by Masami Hiramatsu Committed by Linus Torvalds Apr 28, 2008

list.h: add list_is_singular()



Add list_is_singular() to check a list has just one entry.

list_is_singular() is useful to check whether a list_head which have been
temporarily allocated for listing objects can be released or not.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 3d8d996e

include/linux/list.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -319,6 +319,15 @@ static inline int list_empty_careful(const struct list_head *head)
		return (next == head) && (next == head->prev);
		}

		/**
		* list_is_singular - tests whether a list has just one entry.
		* @head: the list to test.
		*/
		static inline int list_is_singular(const struct list_head *head)
		{
		return !list_empty(head) && (head->next == head->prev);
		}

		static inline void __list_splice(struct list_head *list,
		struct list_head *head)
		{