git.meshlink.io Git - meshlink/blob - src/edge.c

   1 /*
   2     edge.c -- edge tree management
   3     Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License along
  16     with this program; if not, write to the Free Software Foundation, Inc.,
  17     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "system.h"
  21
  22 #include "splay_tree.h"
  23 #include "edge.h"
  24 #include "logger.h"
  25 #include "netutl.h"
  26 #include "node.h"
  27 #include "utils.h"
  28 #include "xalloc.h"
  29
  30 splay_tree_t *edge_weight_tree;
  31
  32 static int edge_compare(const edge_t *a, const edge_t *b) {
  33         return strcmp(a->to->name, b->to->name);
  34 }
  35
  36 static int edge_weight_compare(const edge_t *a, const edge_t *b) {
  37         int result;
  38
  39         result = a->weight - b->weight;
  40
  41         if(result)
  42                 return result;
  43
  44         result = strcmp(a->from->name, b->from->name);
  45
  46         if(result)
  47                 return result;
  48
  49         return strcmp(a->to->name, b->to->name);
  50 }
  51
  52 void init_edges(void) {
  53         edge_weight_tree = splay_alloc_tree((splay_compare_t) edge_weight_compare, NULL);
  54 }
  55
  56 splay_tree_t *new_edge_tree(void) {
  57         return splay_alloc_tree((splay_compare_t) edge_compare, (splay_action_t) free_edge);
  58 }
  59
  60 void free_edge_tree(splay_tree_t *edge_tree) {
  61         splay_delete_tree(edge_tree);
  62 }
  63
  64 void exit_edges(void) {
  65         splay_delete_tree(edge_weight_tree);
  66 }
  67
  68 /* Creation and deletion of connection elements */
  69
  70 edge_t *new_edge(void) {
  71         return xzalloc(sizeof(edge_t));
  72 }
  73
  74 void free_edge(edge_t *e) {
  75         sockaddrfree(&e->address);
  76
  77         free(e);
  78 }
  79
  80 void edge_add(edge_t *e) {
  81         splay_insert(edge_weight_tree, e);
  82         splay_insert(e->from->edge_tree, e);
  83
  84         e->reverse = lookup_edge(e->to, e->from);
  85
  86         if(e->reverse)
  87                 e->reverse->reverse = e;
  88 }
  89
  90 void edge_del(edge_t *e) {
  91         if(e->reverse)
  92                 e->reverse->reverse = NULL;
  93
  94         splay_delete(edge_weight_tree, e);
  95         splay_delete(e->from->edge_tree, e);
  96 }
  97
  98 edge_t *lookup_edge(node_t *from, node_t *to) {
  99         edge_t v;
 100
 101         v.from = from;
 102         v.to = to;
 103
 104         return splay_search(from->edge_tree, &v);
 105 }