src/dlink.cc

   1 /*
   2  * Copyright (C) 1996-2015 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #include "squid.h"
  10 #include "dlink.h"
  11
  12 dlink_list ClientActiveRequests;
  13
  14 void
  15 dlinkAdd(void *data, dlink_node * m, dlink_list * list)
  16 {
  17     m->data = data;
  18     m->prev = NULL;
  19     m->next = list->head;
  20
  21     if (list->head)
  22         list->head->prev = m;
  23
  24     list->head = m;
  25
  26     if (list->tail == NULL)
  27         list->tail = m;
  28 }
  29
  30 void
  31 dlinkAddAfter(void *data, dlink_node * m, dlink_node * n, dlink_list * list)
  32 {
  33     m->data = data;
  34     m->prev = n;
  35     m->next = n->next;
  36
  37     if (n->next)
  38         n->next->prev = m;
  39     else {
  40         assert(list->tail == n);
  41         list->tail = m;
  42     }
  43
  44     n->next = m;
  45 }
  46
  47 void
  48 dlinkAddTail(void *data, dlink_node * m, dlink_list * list)
  49 {
  50     m->data = data;
  51     m->next = NULL;
  52     m->prev = list->tail;
  53
  54     if (list->tail)
  55         list->tail->next = m;
  56
  57     list->tail = m;
  58
  59     if (list->head == NULL)
  60         list->head = m;
  61 }
  62
  63 void
  64 dlinkDelete(dlink_node * m, dlink_list * list)
  65 {
  66     if (m->next)
  67         m->next->prev = m->prev;
  68
  69     if (m->prev)
  70         m->prev->next = m->next;
  71
  72     if (m == list->head)
  73         list->head = m->next;
  74
  75     if (m == list->tail)
  76         list->tail = m->prev;
  77
  78     m->next = m->prev = NULL;
  79 }
  80