X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=list.h;h=66c6d91525031261ff94cd3028e672cb340c06cd;hp=80f36a1ba58ee0032fb3fbd99c4054a03c917cbd;hb=a35c113e0bb9fa9ac02b77eb01dd32f49cd5c8d0;hpb=05527588bd503e4748d801b641a9e3a6556525ad diff --git a/list.h b/list.h index 80f36a1b..66c6d915 100644 --- a/list.h +++ b/list.h @@ -156,17 +156,6 @@ static inline int list_empty(const struct list_head *head) #define list_entry(ptr, type, member) \ container_of(ptr, type, member) -/** - * iterate over a list safe against removal of list entry - * - * \param pos the &struct list_head to use as a loop counter. - * \param n another &struct list_head to use as temporary storage - * \param head the head for your list. - */ -#define list_for_each_safe(pos, n, head) \ - for (pos = (head)->next, n = pos->next; pos != (head); \ - pos = n, n = pos->next) - /** * iterate over list of given type * @@ -204,3 +193,25 @@ static inline int list_empty(const struct list_head *head) n = list_entry(pos->member.prev, typeof(*pos), member); \ &pos->member != (head); \ pos = n, n = list_entry(n->member.prev, typeof(*n), member)) + +/** + * Get the first element from a list + * \param ptr the list head to take the element from. + * \param type The type of the struct this is embedded in. + * \param member The name of the list_struct within the struct. + * + * Note that list is expected to be not empty. + */ +#define list_first_entry(ptr, type, member) \ + list_entry((ptr)->next, type, member) + +/** + * Test whether a list has just one entry. + * + * \param head The list to test. + */ +static inline int list_is_singular(const struct list_head *head) +{ + return !list_empty(head) && (head->next == head->prev); +} +