xref: /aosp_15_r20/external/erofs-utils/include/erofs/list.h (revision 33b1fccf6a0fada2c2875d400ed01119b7676ee5)
1 /* SPDX-License-Identifier: GPL-2.0+ OR Apache-2.0 */
2 /*
3  * Copyright (C) 2018 HUAWEI, Inc.
4  *             http://www.huawei.com/
5  * Created by Li Guifu <[email protected]>
6  */
7 #ifndef __EROFS_LIST_HEAD_H
8 #define __EROFS_LIST_HEAD_H
9 
10 #ifdef __cplusplus
11 extern "C"
12 {
13 #endif
14 
15 #include "defs.h"
16 
17 struct list_head {
18 	struct list_head *prev;
19 	struct list_head *next;
20 };
21 
22 #define LIST_HEAD_INIT(name)                                                   \
23 	{                                                                      \
24 		&(name), &(name)                                               \
25 	}
26 
27 #define LIST_HEAD(name) struct list_head name = LIST_HEAD_INIT(name)
28 
init_list_head(struct list_head * list)29 static inline void init_list_head(struct list_head *list)
30 {
31 	list->prev = list;
32 	list->next = list;
33 }
34 
__list_add(struct list_head * entry,struct list_head * prev,struct list_head * next)35 static inline void __list_add(struct list_head *entry,
36 			      struct list_head *prev,
37 			      struct list_head *next)
38 {
39 	entry->prev = prev;
40 	entry->next = next;
41 	prev->next  = entry;
42 	next->prev  = entry;
43 }
44 
list_add(struct list_head * entry,struct list_head * head)45 static inline void list_add(struct list_head *entry, struct list_head *head)
46 {
47 	__list_add(entry, head, head->next);
48 }
49 
list_add_tail(struct list_head * entry,struct list_head * head)50 static inline void list_add_tail(struct list_head *entry,
51 				 struct list_head *head)
52 {
53 	__list_add(entry, head->prev, head);
54 }
55 
__list_del(struct list_head * prev,struct list_head * next)56 static inline void __list_del(struct list_head *prev, struct list_head *next)
57 {
58 	prev->next = next;
59 	next->prev = prev;
60 }
61 
list_del(struct list_head * entry)62 static inline void list_del(struct list_head *entry)
63 {
64 	__list_del(entry->prev, entry->next);
65 	entry->prev = entry->next = NULL;
66 }
67 
list_empty(struct list_head * head)68 static inline int list_empty(struct list_head *head)
69 {
70 	return head->next == head;
71 }
72 
__list_splice(struct list_head * list,struct list_head * prev,struct list_head * next)73 static inline void __list_splice(struct list_head *list,
74 		struct list_head *prev, struct list_head *next)
75 {
76 	struct list_head *first = list->next;
77 	struct list_head *last = list->prev;
78 
79 	first->prev = prev;
80 	prev->next = first;
81 
82 	last->next = next;
83 	next->prev = last;
84 }
85 
list_splice_tail(struct list_head * list,struct list_head * head)86 static inline void list_splice_tail(struct list_head *list,
87 				    struct list_head *head)
88 {
89 	if (!list_empty(list))
90 		__list_splice(list, head->prev, head);
91 }
92 
93 #define list_entry(ptr, type, member) container_of(ptr, type, member)
94 
95 #define list_first_entry(ptr, type, member)                                    \
96 	list_entry((ptr)->next, type, member)
97 
98 #define list_last_entry(ptr, type, member)                                     \
99 	list_entry((ptr)->prev, type, member)
100 
101 #define list_next_entry(pos, member)                                           \
102 	list_entry((pos)->member.next, typeof(*(pos)), member)
103 
104 #define list_prev_entry(pos, member)                                           \
105 	list_entry((pos)->member.prev, typeof(*(pos)), member)
106 
107 #define list_for_each(pos, head)                                               \
108 	for (pos = (head)->next; pos != (head); pos = pos->next)
109 
110 #define list_for_each_safe(pos, n, head)                                       \
111 	for (pos = (head)->next, n = pos->next; pos != (head);                 \
112 	     pos = n, n = pos->next)
113 
114 #define list_for_each_entry(pos, head, member)                                 \
115 	for (pos = list_first_entry(head, typeof(*pos), member);               \
116 	     &pos->member != (head);                                           \
117 	     pos = list_next_entry(pos, member))
118 
119 #define list_for_each_entry_reverse(pos, head, member)                         \
120 	for (pos = list_last_entry(head, typeof(*pos), member);               \
121 	     &pos->member != (head);                                           \
122 	     pos = list_prev_entry(pos, member))
123 
124 #define list_for_each_entry_from(pos, head, member)                            \
125 	for (; &pos->member != (head); pos = list_next_entry(pos, member))
126 
127 #define list_for_each_entry_safe(pos, n, head, member)                         \
128 	for (pos = list_first_entry(head, typeof(*pos), member),               \
129 	    n    = list_next_entry(pos, member);                               \
130 	     &pos->member != (head);                                           \
131 	     pos = n, n = list_next_entry(n, member))
132 
133 #ifdef __cplusplus
134 }
135 #endif
136 
137 #endif
138