Re: [PATCH] add safe version of list_for_each_entry() to list.h

[Kevin Corry]

On Thursday 03 October 2002 18:44, Greg KH wrote:
> On Thu, Oct 03, 2002 at 06:42:09PM -0500, Mark Peloquin wrote:
> > Please consider adding the following patch to list.h.
>
> This patch had the tabs mangled and would not apply.
>
> Yeah, Notes sucks for sending patches...

It does indeed. Avoid Notes at all costs. :)

Here is the patch again. Should apply cleanly this time.

-Kevin

=========================================================
diff -Naur linux-2.5.40a/include/linux/list.h linux-2.5.40b/include/linux/list.h
--- linux-2.5.40a/include/linux/list.h	Tue Oct  1 02:05:48 2002
+++ linux-2.5.40b/include/linux/list.h	Thu Oct  3 19:17:27 2002
@@ -137,6 +137,15 @@
 	return head->next == head;
 }
 
+/**
+ * list_member - tests whether a list member is currently on a list
+ * @member:	member to evaulate
+ */
+static inline int list_member(struct list_head *member)
+{
+	return ((!member->next || !member->prev) ? 0 : 1);
+}
+
 static inline void __list_splice(struct list_head *list,
 				 struct list_head *head)
 {
@@ -240,6 +249,20 @@
 	     &pos->member != (head); 					\
 	     pos = list_entry(pos->member.next, typeof(*pos), member),	\
 		     prefetch(pos->member.next))
+
+/**
+ * list_for_each_entry_safe - iterate over list safe against removal of list entry
+ * @pos:	the type * to use as a loop counter.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe(pos, n, head, member)			\
+	for (pos = list_entry((head)->next, typeof(*pos), member),	\
+		n = list_entry(pos->member.next, typeof(*pos), member);	\
+	     &pos->member != (head);					\
+	     pos = n,							\
+		n = list_entry(pos->member.next, typeof(*pos), member))
 
 #endif /* __KERNEL__ || _LVM_H_INCLUDE */