ospf6d/ospf6_linklist.c

   1
   2 #include <zebra.h>
   3
   4 #include "ospf6_linklist.h"
   5
   6 static struct linklist_node *
   7 linklist_lookup_node (void *data, struct linklist *linklist)
   8 {
   9   struct linklist_node *node;
  10
  11   for (node = linklist->head; node; node = node->next)
  12     {
  13       if (linklist->cmp && (*linklist->cmp) (node->data, data) == 0)
  14         return node;
  15       if (node->data == data)
  16         return node;
  17     }
  18
  19   return NULL;
  20 }
  21
  22 void *
  23 linklist_lookup (void *data, struct linklist *linklist)
  24 {
  25   struct linklist_node *node;
  26
  27   node = linklist_lookup_node (data, linklist);
  28   if (node)
  29     return node->data;
  30   return NULL;
  31 }
  32
  33 int
  34 linklist_add (void *data, struct linklist *linklist)
  35 {
  36   struct linklist_node *node = NULL, *add;
  37
  38   if (linklist_lookup_node (data, linklist))
  39     return -1;
  40
  41   add = malloc (sizeof (struct linklist_node));
  42   if (add == NULL)
  43     return -1;
  44   memset (add, 0, sizeof (struct linklist_node));
  45   add->data = data;
  46
  47   if (linklist->cmp)
  48     {
  49       for (node = linklist->head; node; node = node->next)
  50         {
  51           if ((*linklist->cmp) (node->data, add->data) > 0)
  52             break;
  53         }
  54     }
  55
  56   if (! node)
  57     {
  58       /* add to tail */
  59       if (linklist->tail)
  60         {
  61           linklist->tail->next = add;
  62           add->prev = linklist->tail;
  63         }
  64       else
  65         {
  66           linklist->head = add;
  67           add->prev = NULL;
  68         }
  69
  70       linklist->tail = add;
  71       add->next = NULL;
  72     }
  73   else
  74     {
  75       /* insert just before 'node' */
  76       if (node->prev)
  77         {
  78           node->prev->next = add;
  79           add->prev = node->prev;
  80         }
  81       else
  82         {
  83           linklist->head = add;
  84           add->prev = NULL;
  85         }
  86
  87       add->next = node;
  88       node->prev = add;
  89     }
  90
  91   linklist->count++;
  92   return 0;
  93 }
  94
  95 int
  96 linklist_remove (void *data, struct linklist *linklist)
  97 {
  98   struct linklist_node *rem;
  99
 100   rem = linklist_lookup_node (data, linklist);
 101   if (rem == NULL)
 102     return -1;
 103
 104   if (rem->prev)
 105     rem->prev->next = rem->next;
 106   else
 107     linklist->head = rem->next;
 108
 109   if (rem->next)
 110     rem->next->prev = rem->prev;
 111   else
 112     linklist->tail = rem->prev;
 113
 114   free (rem);
 115   linklist->count--;
 116   return 0;
 117 }
 118
 119 void
 120 linklist_head (struct linklist *linklist, struct linklist_node *node)
 121 {
 122   if (linklist->head == NULL)
 123     {
 124       node->prev = NULL;
 125       node->next = NULL;
 126       node->data = NULL;
 127       return;
 128     }
 129
 130   node->prev = linklist->head->prev;
 131   node->next = linklist->head->next;
 132   node->data = linklist->head->data;
 133 }
 134
 135 int
 136 linklist_end (struct linklist_node *node)
 137 {
 138   if (node->data == NULL && node->next == NULL)
 139     return 1;
 140   return 0;
 141 }
 142
 143 void
 144 linklist_next (struct linklist_node *node)
 145 {
 146   if (node->next == NULL)
 147     {
 148       node->prev = NULL;
 149       node->next = NULL;
 150       node->data = NULL;
 151       return;
 152     }
 153
 154   node->data = node->next->data;
 155   node->prev = node->next->prev;
 156   node->next = node->next->next;
 157 }
 158
 159 struct linklist *
 160 linklist_create ()
 161 {
 162   struct linklist *linklist;
 163
 164   linklist = malloc (sizeof (struct linklist));
 165   if (linklist == NULL)
 166     return NULL;
 167   memset (linklist, 0, sizeof (struct linklist));
 168
 169   return linklist;
 170 }
 171
 172 void
 173 linklist_remove_all (struct linklist *linklist)
 174 {
 175   struct linklist_node node;
 176
 177   for (linklist_head (linklist, &node); ! linklist_end (&node);
 178        linklist_next (&node))
 179     linklist_remove (node.data, linklist);
 180 }
 181
 182 void
 183 linklist_delete (struct linklist *linklist)
 184 {
 185   linklist_remove_all (linklist);
 186   assert (linklist->count == 0);
 187   assert (linklist->head == NULL);
 188   assert (linklist->tail == NULL);
 189
 190   free (linklist);
 191 }
 192
 193