1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * erofs-utils/include/erofs/list.h
4 *
5 * Copyright (C) 2018 HUAWEI, Inc.
6 * http://www.huawei.com/
7 * Created by Li Guifu <bluce.liguifu@huawei.com>
8 */
9 #ifndef __EROFS_LIST_HEAD_H
10 #define __EROFS_LIST_HEAD_H
11
12 #include "defs.h"
13
14 struct list_head {
15 struct list_head *prev;
16 struct list_head *next;
17 };
18
19 #define LIST_HEAD_INIT(name) \
20 { \
21 &(name), &(name) \
22 }
23
24 #define LIST_HEAD(name) struct list_head name = LIST_HEAD_INIT(name)
25
init_list_head(struct list_head * list)26 static inline void init_list_head(struct list_head *list)
27 {
28 list->prev = list;
29 list->next = list;
30 }
31
__list_add(struct list_head * entry,struct list_head * prev,struct list_head * next)32 static inline void __list_add(struct list_head *entry,
33 struct list_head *prev,
34 struct list_head *next)
35 {
36 entry->prev = prev;
37 entry->next = next;
38 prev->next = entry;
39 next->prev = entry;
40 }
41
list_add(struct list_head * entry,struct list_head * head)42 static inline void list_add(struct list_head *entry, struct list_head *head)
43 {
44 __list_add(entry, head, head->next);
45 }
46
list_add_tail(struct list_head * entry,struct list_head * head)47 static inline void list_add_tail(struct list_head *entry,
48 struct list_head *head)
49 {
50 __list_add(entry, head->prev, head);
51 }
52
__list_del(struct list_head * prev,struct list_head * next)53 static inline void __list_del(struct list_head *prev, struct list_head *next)
54 {
55 prev->next = next;
56 next->prev = prev;
57 }
58
list_del(struct list_head * entry)59 static inline void list_del(struct list_head *entry)
60 {
61 __list_del(entry->prev, entry->next);
62 entry->prev = entry->next = NULL;
63 }
64
list_empty(struct list_head * head)65 static inline int list_empty(struct list_head *head)
66 {
67 return head->next == head;
68 }
69
70 #define list_entry(ptr, type, member) container_of(ptr, type, member)
71
72 #define list_first_entry(ptr, type, member) \
73 list_entry((ptr)->next, type, member)
74
75 #define list_last_entry(ptr, type, member) \
76 list_entry((ptr)->prev, type, member)
77
78 #define list_next_entry(pos, member) \
79 list_entry((pos)->member.next, typeof(*(pos)), member)
80
81 #define list_prev_entry(pos, member) \
82 list_entry((pos)->member.prev, typeof(*(pos)), member)
83
84 #define list_for_each(pos, head) \
85 for (pos = (head)->next; pos != (head); pos = pos->next)
86
87 #define list_for_each_safe(pos, n, head) \
88 for (pos = (head)->next, n = pos->next; pos != (head); \
89 pos = n, n = pos->next)
90
91 #define list_for_each_entry(pos, head, member) \
92 for (pos = list_first_entry(head, typeof(*pos), member); \
93 &pos->member != (head); \
94 pos = list_next_entry(pos, member))
95
96 #define list_for_each_entry_reverse(pos, head, member) \
97 for (pos = list_last_entry(head, typeof(*pos), member); \
98 &pos->member != (head); \
99 pos = list_prev_entry(pos, member))
100
101 #define list_for_each_entry_from(pos, head, member) \
102 for (; &pos->member != (head); pos = list_next_entry(pos, member))
103
104 #define list_for_each_entry_safe(pos, n, head, member) \
105 for (pos = list_first_entry(head, typeof(*pos), member), \
106 n = list_next_entry(pos, member); \
107 &pos->member != (head); \
108 pos = n, n = list_next_entry(n, member))
109
110 #endif
111