1 /* Copyright (c) 2013, Ben Noordhuis <info@bnoordhuis.nl>
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
10 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
12 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
13 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14 */
15
16 #ifndef QUEUE_H_
17 #define QUEUE_H_
18
19 #include <stddef.h>
20
21 #define uv__queue_data(pointer, type, field) \
22 ((type*) ((char*) (pointer) - offsetof(type, field)))
23
24 #define uv__queue_foreach(q, h) \
25 for ((q) = (h)->next; (q) != (h); (q) = (q)->next)
26
uv__queue_init(struct uv__queue * q)27 static inline void uv__queue_init(struct uv__queue* q) {
28 q->next = q;
29 q->prev = q;
30 }
31
uv__queue_empty(const struct uv__queue * q)32 static inline int uv__queue_empty(const struct uv__queue* q) {
33 return q == q->next;
34 }
35
uv__queue_head(const struct uv__queue * q)36 static inline struct uv__queue* uv__queue_head(const struct uv__queue* q) {
37 return q->next;
38 }
39
uv__queue_next(const struct uv__queue * q)40 static inline struct uv__queue* uv__queue_next(const struct uv__queue* q) {
41 return q->next;
42 }
43
uv__queue_add(struct uv__queue * h,struct uv__queue * n)44 static inline void uv__queue_add(struct uv__queue* h, struct uv__queue* n) {
45 h->prev->next = n->next;
46 n->next->prev = h->prev;
47 h->prev = n->prev;
48 h->prev->next = h;
49 }
50
uv__queue_split(struct uv__queue * h,struct uv__queue * q,struct uv__queue * n)51 static inline void uv__queue_split(struct uv__queue* h,
52 struct uv__queue* q,
53 struct uv__queue* n) {
54 n->prev = h->prev;
55 n->prev->next = n;
56 n->next = q;
57 h->prev = q->prev;
58 h->prev->next = h;
59 q->prev = n;
60 }
61
uv__queue_move(struct uv__queue * h,struct uv__queue * n)62 static inline void uv__queue_move(struct uv__queue* h, struct uv__queue* n) {
63 if (uv__queue_empty(h))
64 uv__queue_init(n);
65 else
66 uv__queue_split(h, h->next, n);
67 }
68
uv__queue_insert_head(struct uv__queue * h,struct uv__queue * q)69 static inline void uv__queue_insert_head(struct uv__queue* h,
70 struct uv__queue* q) {
71 q->next = h->next;
72 q->prev = h;
73 q->next->prev = q;
74 h->next = q;
75 }
76
uv__queue_insert_tail(struct uv__queue * h,struct uv__queue * q)77 static inline void uv__queue_insert_tail(struct uv__queue* h,
78 struct uv__queue* q) {
79 q->next = h;
80 q->prev = h->prev;
81 q->prev->next = q;
82 h->prev = q;
83 }
84
uv__queue_remove(struct uv__queue * q)85 static inline void uv__queue_remove(struct uv__queue* q) {
86 q->prev->next = q->next;
87 q->next->prev = q->prev;
88 }
89
90 #endif /* QUEUE_H_ */
91
