1 /*
2 * Copyright (c) 2017 Fastly, Kazuho Oku
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to
6 * deal in the Software without restriction, including without limitation the
7 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
8 * sell copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
20 * IN THE SOFTWARE.
21 */
22 #ifndef quicly_linklist_h
23 #define quicly_linklist_h
24
25 #ifdef __cplusplus
26 extern "C" {
27 #endif
28
29 #include <assert.h>
30
31 typedef struct st_quicly_linklist_t {
32 struct st_quicly_linklist_t *prev;
33 struct st_quicly_linklist_t *next;
34 } quicly_linklist_t;
35
36 static void quicly_linklist_init(quicly_linklist_t *l);
37 static int quicly_linklist_is_linked(quicly_linklist_t *l);
38 static void quicly_linklist_insert(quicly_linklist_t *prev, quicly_linklist_t *n);
39 static void quicly_linklist_unlink(quicly_linklist_t *l);
40 static void quicly_linklist_insert_list(quicly_linklist_t *prev, quicly_linklist_t *l);
41
42 /* inline functions */
43
quicly_linklist_init(quicly_linklist_t * l)44 inline void quicly_linklist_init(quicly_linklist_t *l)
45 {
46 l->prev = l->next = l;
47 }
48
quicly_linklist_is_linked(quicly_linklist_t * l)49 inline int quicly_linklist_is_linked(quicly_linklist_t *l)
50 {
51 return l->prev != l;
52 }
53
quicly_linklist_insert(quicly_linklist_t * prev,quicly_linklist_t * n)54 inline void quicly_linklist_insert(quicly_linklist_t *prev, quicly_linklist_t *n)
55 {
56 assert(!quicly_linklist_is_linked(n));
57 n->prev = prev;
58 n->next = prev->next;
59 n->prev->next = n;
60 n->next->prev = n;
61 }
62
quicly_linklist_unlink(quicly_linklist_t * l)63 inline void quicly_linklist_unlink(quicly_linklist_t *l)
64 {
65 l->prev->next = l->next;
66 l->next->prev = l->prev;
67 quicly_linklist_init(l);
68 }
69
quicly_linklist_insert_list(quicly_linklist_t * prev,quicly_linklist_t * l)70 inline void quicly_linklist_insert_list(quicly_linklist_t *prev, quicly_linklist_t *l)
71 {
72 if (quicly_linklist_is_linked(l)) {
73 l->next->prev = prev;
74 l->prev->next = prev->next;
75 prev->next->prev = l->prev;
76 prev->next = l->next;
77 quicly_linklist_init(l);
78 }
79 }
80
81 #ifdef __cplusplus
82 }
83 #endif
84
85 #endif
86