1 struct list_head {
2 	struct list_head *next;
3 };
4 
5 #define LIST_HEAD(name) \
6 	struct list_head name = { &(name) }
7 
list_empty(const struct list_head * head)8 static inline int list_empty(const struct list_head *head)
9 {
10 	return head->next == head;
11 }
12 
list_add(struct list_head * new,struct list_head * head)13 static inline void list_add(struct list_head *new, struct list_head *head)
14 {
15 	new->next = head->next;
16 	head->next = new;
17 }
18 
list_del(struct list_head * entry,struct list_head * prev)19 static inline void list_del(struct list_head *entry, struct list_head *prev)
20 {
21 	prev->next = entry->next;
22 	entry->next = entry;
23 }
24 
25 #define list_for_each_safe(pos, n, head) \
26 	for (n = (head), pos = (head)->next; pos != (head); \
27 	     n = pos, pos = n->next)
28 
29 #undef offsetof
30 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
31 
32 #define container_of(ptr, type, member) ({			\
33 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
34 	(type *)( (char *)__mptr - offsetof(type,member) );})
35 
36 #ifdef DEBUG
37 #define pynl_dbg(fmt, ...) \
38 	fprintf(stderr, "%s: " fmt, __func__, __VA_ARGS__)
39 #else
40 #define pynl_dbg(fmt, ...)
41 #endif
42