1 #ifndef _LISTHELP_H
2 #define _LISTHELP_H
3 #include <linux/config.h>
4 #include <linux/list.h>
5 #include <linux/netfilter_ipv4/lockhelp.h>
6
7 /* Header to do more comprehensive job than linux/list.h; assume list
8 is first entry in structure. */
9
10 /* Return pointer to first true entry, if any, or NULL. A macro
11 required to allow inlining of cmpfn. */
12 #define LIST_FIND(head, cmpfn, type, args...) \
13 ({ \
14 const struct list_head *__i, *__j = NULL; \
15 \
16 ASSERT_READ_LOCK(head); \
17 list_for_each(__i, (head)) \
18 if (cmpfn((const type)__i , ## args)) { \
19 __j = __i; \
20 break; \
21 } \
22 (type)__j; \
23 })
24
25 #define LIST_FIND_W(head, cmpfn, type, args...) \
26 ({ \
27 const struct list_head *__i, *__j = NULL; \
28 \
29 ASSERT_WRITE_LOCK(head); \
30 list_for_each(__i, (head)) \
31 if (cmpfn((type)__i , ## args)) { \
32 __j = __i; \
33 break; \
34 } \
35 (type)__j; \
36 })
37
38 /* Just like LIST_FIND but we search backwards */
39 #define LIST_FIND_B(head, cmpfn, type, args...) \
40 ({ \
41 const struct list_head *__i, *__j = NULL; \
42 \
43 ASSERT_READ_LOCK(head); \
44 list_for_each_prev(__i, (head)) \
45 if (cmpfn((const type)__i , ## args)) { \
46 __j = __i; \
47 break; \
48 } \
49 (type)__j; \
50 })
51
52 static inline int
__list_cmp_same(const void * p1,const void * p2)53 __list_cmp_same(const void *p1, const void *p2) { return p1 == p2; }
54
55 /* Is this entry in the list? */
56 static inline int
list_inlist(struct list_head * head,const void * entry)57 list_inlist(struct list_head *head, const void *entry)
58 {
59 return LIST_FIND(head, __list_cmp_same, void *, entry) != NULL;
60 }
61
62 /* Delete from list. */
63 #ifdef CONFIG_NETFILTER_DEBUG
64 #define LIST_DELETE(head, oldentry) \
65 do { \
66 ASSERT_WRITE_LOCK(head); \
67 if (!list_inlist(head, oldentry)) \
68 printk("LIST_DELETE: %s:%u `%s'(%p) not in %s.\n", \
69 __FILE__, __LINE__, #oldentry, oldentry, #head); \
70 else list_del((struct list_head *)oldentry); \
71 } while(0)
72 #else
73 #define LIST_DELETE(head, oldentry) list_del((struct list_head *)oldentry)
74 #endif
75
76 /* Append. */
77 static inline void
list_append(struct list_head * head,void * new)78 list_append(struct list_head *head, void *new)
79 {
80 ASSERT_WRITE_LOCK(head);
81 list_add((new), (head)->prev);
82 }
83
84 /* Prepend. */
85 static inline void
list_prepend(struct list_head * head,void * new)86 list_prepend(struct list_head *head, void *new)
87 {
88 ASSERT_WRITE_LOCK(head);
89 list_add(new, head);
90 }
91
92 /* Insert according to ordering function; insert before first true. */
93 #define LIST_INSERT(head, new, cmpfn) \
94 do { \
95 struct list_head *__i; \
96 ASSERT_WRITE_LOCK(head); \
97 list_for_each(__i, (head)) \
98 if ((new), (typeof (new))__i) \
99 break; \
100 list_add((struct list_head *)(new), __i->prev); \
101 } while(0)
102
103 /* If the field after the list_head is a nul-terminated string, you
104 can use these functions. */
__list_cmp_name(const void * i,const char * name)105 static inline int __list_cmp_name(const void *i, const char *name)
106 {
107 return strcmp(name, i+sizeof(struct list_head)) == 0;
108 }
109
110 /* Returns false if same name already in list, otherwise does insert. */
111 static inline int
list_named_insert(struct list_head * head,void * new)112 list_named_insert(struct list_head *head, void *new)
113 {
114 if (LIST_FIND(head, __list_cmp_name, void *,
115 new + sizeof(struct list_head)))
116 return 0;
117 list_prepend(head, new);
118 return 1;
119 }
120
121 /* Find this named element in the list. */
122 #define list_named_find(head, name) \
123 LIST_FIND(head, __list_cmp_name, void *, name)
124
125 #endif /*_LISTHELP_H*/
126