source: trunk/packages/xen-3.1/xen-3.1/tools/vnet/vnetd/list.h @ 34

Last change on this file since 34 was 34, checked in by hartmans, 18 years ago

Add xen and xen-common

File size: 7.8 KB
Line 
1#ifndef _VNETD_LIST_H_
2#define _VNETD_LIST_H_
3
4/* Taken from Linux kernel code, but de-kernelized for userspace. */
5#include <stddef.h>
6
7/*
8 * These are non-NULL pointers that will result in page faults
9 * under normal circumstances, used to verify that nobody uses
10 * non-initialized list entries.
11 */
12#define LIST_POISON1  ((void *) 0x00100100)
13#define LIST_POISON2  ((void *) 0x00200200)
14
15#define container_of(ptr, type, member) ({                      \
16        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
17        (type *)( (char *)__mptr - offsetof(type,member) );})
18
19/*
20 * Simple doubly linked list implementation.
21 *
22 * Some of the internal functions ("__xxx") are useful when
23 * manipulating whole lists rather than single entries, as
24 * sometimes we already know the next/prev entries and we can
25 * generate better code by using them directly rather than
26 * using the generic single-entry routines.
27 */
28
29struct list_head {
30        struct list_head *next, *prev;
31};
32
33#define LIST_HEAD_INIT(name) { &(name), &(name) }
34
35#define LIST_HEAD(name) \
36        struct list_head name = LIST_HEAD_INIT(name)
37
38#define INIT_LIST_HEAD(ptr) do { \
39        (ptr)->next = (ptr); (ptr)->prev = (ptr); \
40} while (0)
41
42/*
43 * Insert a new entry between two known consecutive entries.
44 *
45 * This is only for internal list manipulation where we know
46 * the prev/next entries already!
47 */
48static inline void __list_add(struct list_head *new,
49                              struct list_head *prev,
50                              struct list_head *next)
51{
52        next->prev = new;
53        new->next = next;
54        new->prev = prev;
55        prev->next = new;
56}
57
58/**
59 * list_add - add a new entry
60 * @new: new entry to be added
61 * @head: list head to add it after
62 *
63 * Insert a new entry after the specified head.
64 * This is good for implementing stacks.
65 */
66static inline void list_add(struct list_head *new, struct list_head *head)
67{
68        __list_add(new, head, head->next);
69}
70
71/**
72 * list_add_tail - add a new entry
73 * @new: new entry to be added
74 * @head: list head to add it before
75 *
76 * Insert a new entry before the specified head.
77 * This is useful for implementing queues.
78 */
79static inline void list_add_tail(struct list_head *new, struct list_head *head)
80{
81        __list_add(new, head->prev, head);
82}
83
84/*
85 * Delete a list entry by making the prev/next entries
86 * point to each other.
87 *
88 * This is only for internal list manipulation where we know
89 * the prev/next entries already!
90 */
91static inline void __list_del(struct list_head * prev, struct list_head * next)
92{
93        next->prev = prev;
94        prev->next = next;
95}
96
97/**
98 * list_del - deletes entry from list.
99 * @entry: the element to delete from the list.
100 * Note: list_empty on entry does not return true after this, the entry is
101 * in an undefined state.
102 */
103static inline void list_del(struct list_head *entry)
104{
105        __list_del(entry->prev, entry->next);
106        entry->next = LIST_POISON1;
107        entry->prev = LIST_POISON2;
108}
109
110/**
111 * list_del_rcu - deletes entry from list without re-initialization
112 * @entry: the element to delete from the list.
113 *
114 * Note: list_empty on entry does not return true after this,
115 * the entry is in an undefined state. It is useful for RCU based
116 * lockfree traversal.
117 *
118 * In particular, it means that we can not poison the forward
119 * pointers that may still be used for walking the list.
120 */
121static inline void list_del_rcu(struct list_head *entry)
122{
123        __list_del(entry->prev, entry->next);
124        entry->prev = LIST_POISON2;
125}
126
127/**
128 * list_del_init - deletes entry from list and reinitialize it.
129 * @entry: the element to delete from the list.
130 */
131static inline void list_del_init(struct list_head *entry)
132{
133        __list_del(entry->prev, entry->next);
134        INIT_LIST_HEAD(entry); 
135}
136
137/**
138 * list_move - delete from one list and add as another's head
139 * @list: the entry to move
140 * @head: the head that will precede our entry
141 */
142static inline void list_move(struct list_head *list, struct list_head *head)
143{
144        __list_del(list->prev, list->next);
145        list_add(list, head);
146}
147
148/**
149 * list_move_tail - delete from one list and add as another's tail
150 * @list: the entry to move
151 * @head: the head that will follow our entry
152 */
153static inline void list_move_tail(struct list_head *list,
154                                  struct list_head *head)
155{
156        __list_del(list->prev, list->next);
157        list_add_tail(list, head);
158}
159
160/**
161 * list_empty - tests whether a list is empty
162 * @head: the list to test.
163 */
164static inline int list_empty(struct list_head *head)
165{
166        return head->next == head;
167}
168
169static inline void __list_splice(struct list_head *list,
170                                 struct list_head *head)
171{
172        struct list_head *first = list->next;
173        struct list_head *last = list->prev;
174        struct list_head *at = head->next;
175
176        first->prev = head;
177        head->next = first;
178
179        last->next = at;
180        at->prev = last;
181}
182
183/**
184 * list_splice - join two lists
185 * @list: the new list to add.
186 * @head: the place to add it in the first list.
187 */
188static inline void list_splice(struct list_head *list, struct list_head *head)
189{
190        if (!list_empty(list))
191                __list_splice(list, head);
192}
193
194/**
195 * list_splice_init - join two lists and reinitialise the emptied list.
196 * @list: the new list to add.
197 * @head: the place to add it in the first list.
198 *
199 * The list at @list is reinitialised
200 */
201static inline void list_splice_init(struct list_head *list,
202                                    struct list_head *head)
203{
204        if (!list_empty(list)) {
205                __list_splice(list, head);
206                INIT_LIST_HEAD(list);
207        }
208}
209
210/**
211 * list_entry - get the struct for this entry
212 * @ptr:        the &struct list_head pointer.
213 * @type:       the type of the struct this is embedded in.
214 * @member:     the name of the list_struct within the struct.
215 */
216#define list_entry(ptr, type, member) \
217        container_of(ptr, type, member)
218
219/**
220 * list_for_each        -       iterate over a list
221 * @pos:        the &struct list_head to use as a loop counter.
222 * @head:       the head for your list.
223 */
224#define list_for_each(pos, head) \
225        for (pos = (head)->next; pos != (head); pos = pos->next)
226
227/**
228 * list_for_each_prev   -       iterate over a list backwards
229 * @pos:        the &struct list_head to use as a loop counter.
230 * @head:       the head for your list.
231 */
232#define list_for_each_prev(pos, head) \
233        for (pos = (head)->prev; pos != (head); pos = pos->prev)
234               
235/**
236 * list_for_each_safe   -       iterate over a list safe against removal of list entry
237 * @pos:        the &struct list_head to use as a loop counter.
238 * @n:          another &struct list_head to use as temporary storage
239 * @head:       the head for your list.
240 */
241#define list_for_each_safe(pos, n, head) \
242        for (pos = (head)->next, n = pos->next; pos != (head); \
243                pos = n, n = pos->next)
244
245/**
246 * list_for_each_entry  -       iterate over list of given type
247 * @pos:        the type * to use as a loop counter.
248 * @head:       the head for your list.
249 * @member:     the name of the list_struct within the struct.
250 */
251#define list_for_each_entry(pos, head, member)                          \
252        for (pos = list_entry((head)->next, typeof(*pos), member);      \
253             &pos->member != (head);                                    \
254             pos = list_entry(pos->member.next, typeof(*pos), member))
255
256/**
257 * list_for_each_entry_reverse - iterate backwards over list of given type.
258 * @pos:        the type * to use as a loop counter.
259 * @head:       the head for your list.
260 * @member:     the name of the list_struct within the struct.
261 */
262#define list_for_each_entry_reverse(pos, head, member)                  \
263        for (pos = list_entry((head)->prev, typeof(*pos), member);      \
264             &pos->member != (head);                                    \
265             pos = list_entry(pos->member.prev, typeof(*pos), member))
266
267
268/**
269 * list_for_each_entry_safe - iterate over list of given type safe against
270 *  removal of list entry
271 * @pos:        the type * to use as a loop counter.
272 * @n:          another type * to use as temporary storage
273 * @head:       the head for your list.
274 * @member:     the name of the list_struct within the struct.
275 */
276#define list_for_each_entry_safe(pos, n, head, member)                  \
277        for (pos = list_entry((head)->next, typeof(*pos), member),      \
278                n = list_entry(pos->member.next, typeof(*pos), member); \
279             &pos->member != (head);                                    \
280             pos = n, n = list_entry(n->member.next, typeof(*n), member))
281
282
283
284#endif /* _VNETD_LIST_H_ */
Note: See TracBrowser for help on using the repository browser.