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Subject[PATCH 1/2] list: add list_for_each_entry_del
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I have seen a lot of boilerplate code that either follows the pattern of
while (!list_empty(head)) {
pos = list_entry(head->next, struct foo, list);
list_del(pos->list);
...
}
or some variant thereof.

With this patch in, people can use
list_for_each_entry_del(pos, head, list) {
...
}

The patch also adds a list_for_each_del variant, even though I have
only found a single user for that one so far.

Signed-off-by: Joern Engel <joern@logfs.org>
---
include/linux/list.h | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/include/linux/list.h b/include/linux/list.h
index 6a1f8df..e09fe10 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -361,6 +361,17 @@ static inline void list_splice_tail_init(struct list_head *list,
#define list_first_entry(ptr, type, member) \
list_entry((ptr)->next, type, member)

+static inline struct list_head *list_first_del(struct list_head *head)
+{
+ struct list_head *item;
+
+ if (list_empty(head))
+ return NULL;
+ item = head->next;
+ list_del(item);
+ return item;
+}
+
/**
* list_for_each - iterate over a list
* @pos: the &struct list_head to use as a loop cursor.
@@ -483,6 +494,28 @@ static inline void list_splice_tail_init(struct list_head *list,
pos = list_entry(pos->member.next, typeof(*pos), member))

/**
+ * list_for_each_remove - iterate over a list, deleting each entry
+ * @pos: the &struct list_head to use as a loop cursor.
+ * @head: the head of your list.
+ *
+ * Calls list_del() on pos on each iteration
+ */
+#define list_for_each_del(pos, head) \
+ while ((pos = list_first_del(head)))
+
+/**
+ * list_for_each_entry_remove - iterate over a list of given type, deleting each entry
+ * @pos: the type * to use as loop cursor.
+ * @head: the head of your list.
+ * @member: the name of the list_struct within the struct
+ *
+ * Calls list_del() on pos on each iteration
+ */
+#define list_for_each_entry_del(pos, head, member) \
+ while (pos = list_entry(list_first_del(head), typeof(*pos), member), \
+ &pos->member)
+
+/**
* list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
* @pos: the type * to use as a loop cursor.
* @n: another type * to use as temporary storage
--
1.7.10.4


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