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_node use explicit alloc()/freeOne()
  13  * XXX: convert to MEMPROXY_CLASS() API
  14  */
  15 #include "mem/Pool.h"
  16
  17 dlink_list ClientActiveRequests;
  18
  19 MemAllocator *dlink_node_pool = NULL;
  20
  21 dlink_node *
  22 dlinkNodeNew()
  23 {
  24     if (dlink_node_pool == NULL)
  25         dlink_node_pool = memPoolCreate("Dlink list nodes", sizeof(dlink_node));
  26
  27     /* where should we call delete dlink_node_pool;dlink_node_pool = NULL; */
  28     return (dlink_node *)dlink_node_pool->alloc();
  29 }
  30
  31 /** The node needs to be unlinked FIRST */
  32 void
  33 dlinkNodeDelete(dlink_node * m)
  34 {
  35     if (m == NULL)
  36         return;
  37
  38     dlink_node_pool->freeOne(m);
  39 }
  40
  41 void
  42 dlinkAdd(void *data, dlink_node * m, dlink_list * list)
  43 {
  44     m->data = data;
  45     m->prev = NULL;
  46     m->next = list->head;
  47
  48     if (list->head)
  49         list->head->prev = m;
  50
  51     list->head = m;
  52
  53     if (list->tail == NULL)
  54         list->tail = m;
  55 }
  56
  57 void
  58 dlinkAddAfter(void *data, dlink_node * m, dlink_node * n, dlink_list * list)
  59 {
  60     m->data = data;
  61     m->prev = n;
  62     m->next = n->next;
  63
  64     if (n->next)
  65         n->next->prev = m;
  66     else {
  67         assert(list->tail == n);
  68         list->tail = m;
  69     }
  70
  71     n->next = m;
  72 }
  73
  74 void
  75 dlinkAddTail(void *data, dlink_node * m, dlink_list * list)
  76 {
  77     m->data = data;
  78     m->next = NULL;
  79     m->prev = list->tail;
  80
  81     if (list->tail)
  82         list->tail->next = m;
  83
  84     list->tail = m;
  85
  86     if (list->head == NULL)
  87         list->head = m;
  88 }
  89
  90 void
  91 dlinkDelete(dlink_node * m, dlink_list * list)
  92 {
  93     if (m->next)
  94         m->next->prev = m->prev;
  95
  96     if (m->prev)
  97         m->prev->next = m->next;
  98
  99     if (m == list->head)
 100         list->head = m->next;
 101
 102     if (m == list->tail)
 103         list->tail = m->prev;
 104
 105     m->next = m->prev = NULL;
 106 }
 107