#define LIST_ENTRY(__type, __item, __field) \
((__type *)(((char *)(__item)) - offsetof(__type, __field)))
-
+#define LIST_IS_EMPTY(__list) \
+ ((__list)->next == (__list))
+
+#ifndef container_of
+#define container_of(ptr, sample, member) \
+ (void *)((char *)(ptr) \
+ - ((char *)&(sample)->member - (char *)(sample)))
+#endif
+
+#define LIST_FOR_EACH_ENTRY(pos, head, member) \
+ for (pos = container_of((head)->next, pos, member); \
+ &pos->member != (head); \
+ pos = container_of(pos->member.next, pos, member))
+
+#define LIST_FOR_EACH_ENTRY_SAFE(pos, storage, head, member) \
+ for (pos = container_of((head)->next, pos, member), \
+ storage = container_of(pos->member.next, pos, member); \
+ &pos->member != (head); \
+ pos = storage, storage = container_of(storage->member.next, storage, member))
#endif /*_U_DOUBLE_LIST_H_*/