release/src/router/nginx/src/core/ngx_queue.h

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  * Copyright (C) Nginx, Inc.
   5  */
   6
   7
   8 #include <ngx_config.h>
   9 #include <ngx_core.h>
  10
  11
  12 #ifndef _NGX_QUEUE_H_INCLUDED_
  13 #define _NGX_QUEUE_H_INCLUDED_
  14
  15
  16 typedef struct ngx_queue_s  ngx_queue_t;
  17
  18 struct ngx_queue_s {
  19     ngx_queue_t  *prev;
  20     ngx_queue_t  *next;
  21 };
  22
  23
  24 #define ngx_queue_init(q)                                                     \
  25     (q)->prev = q;                                                            \
  26     (q)->next = q
  27
  28
  29 #define ngx_queue_empty(h)                                                    \
  30     (h == (h)->prev)
  31
  32
  33 #define ngx_queue_insert_head(h, x)                                           \
  34     (x)->next = (h)->next;                                                    \
  35     (x)->next->prev = x;                                                      \
  36     (x)->prev = h;                                                            \
  37     (h)->next = x
  38
  39
  40 #define ngx_queue_insert_after   ngx_queue_insert_head
  41
  42
  43 #define ngx_queue_insert_tail(h, x)                                           \
  44     (x)->prev = (h)->prev;                                                    \
  45     (x)->prev->next = x;                                                      \
  46     (x)->next = h;                                                            \
  47     (h)->prev = x
  48
  49
  50 #define ngx_queue_head(h)                                                     \
  51     (h)->next
  52
  53
  54 #define ngx_queue_last(h)                                                     \
  55     (h)->prev
  56
  57
  58 #define ngx_queue_sentinel(h)                                                 \
  59     (h)
  60
  61
  62 #define ngx_queue_next(q)                                                     \
  63     (q)->next
  64
  65
  66 #define ngx_queue_prev(q)                                                     \
  67     (q)->prev
  68
  69
  70 #if (NGX_DEBUG)
  71
  72 #define ngx_queue_remove(x)                                                   \
  73     (x)->next->prev = (x)->prev;                                              \
  74     (x)->prev->next = (x)->next;                                              \
  75     (x)->prev = NULL;                                                         \
  76     (x)->next = NULL
  77
  78 #else
  79
  80 #define ngx_queue_remove(x)                                                   \
  81     (x)->next->prev = (x)->prev;                                              \
  82     (x)->prev->next = (x)->next
  83
  84 #endif
  85
  86
  87 #define ngx_queue_split(h, q, n)                                              \
  88     (n)->prev = (h)->prev;                                                    \
  89     (n)->prev->next = n;                                                      \
  90     (n)->next = q;                                                            \
  91     (h)->prev = (q)->prev;                                                    \
  92     (h)->prev->next = h;                                                      \
  93     (q)->prev = n;
  94
  95
  96 #define ngx_queue_add(h, n)                                                   \
  97     (h)->prev->next = (n)->next;                                              \
  98     (n)->next->prev = (h)->prev;                                              \
  99     (h)->prev = (n)->prev;                                                    \
 100     (h)->prev->next = h;
 101
 102
 103 #define ngx_queue_data(q, type, link)                                         \
 104     (type *) ((u_char *) q - offsetof(type, link))
 105
 106
 107 ngx_queue_t *ngx_queue_middle(ngx_queue_t *queue);
 108 void ngx_queue_sort(ngx_queue_t *queue,
 109     ngx_int_t (*cmp)(const ngx_queue_t *, const ngx_queue_t *));
 110
 111
 112 #endif /* _NGX_QUEUE_H_INCLUDED_ */