blob: 3cacaf3a883853e4c9fce0bd60222bb7cf637fbc (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
/*
* Copyright (C) Igor Sysoev
* Copyright (C) Nginx, Inc.
*/
#include <ngx_config.h>
#include <ngx_core.h>
/*
* find the middle queue element if the queue has odd number of elements
* or the first element of the queue's second part otherwise
*/
ngx_queue_t *
ngx_queue_middle(ngx_queue_t *queue)
{
ngx_queue_t *middle, *next;
middle = ngx_queue_head(queue);
if (middle == ngx_queue_last(queue)) {
return middle;
}
next = ngx_queue_head(queue);
for ( ;; ) {
middle = ngx_queue_next(middle);
next = ngx_queue_next(next);
if (next == ngx_queue_last(queue)) {
return middle;
}
next = ngx_queue_next(next);
if (next == ngx_queue_last(queue)) {
return middle;
}
}
}
/* the stable insertion sort */
void
ngx_queue_sort(ngx_queue_t *queue,
ngx_int_t (*cmp)(const ngx_queue_t *, const ngx_queue_t *))
{
ngx_queue_t *q, *prev, *next;
q = ngx_queue_head(queue);
if (q == ngx_queue_last(queue)) {
return;
}
for (q = ngx_queue_next(q); q != ngx_queue_sentinel(queue); q = next) {
prev = ngx_queue_prev(q);
next = ngx_queue_next(q);
ngx_queue_remove(q);
do {
if (cmp(prev, q) <= 0) {
break;
}
prev = ngx_queue_prev(prev);
} while (prev != ngx_queue_sentinel(queue));
ngx_queue_insert_after(prev, q);
}
}
|
