rstplib/vector.c

   1 /************************************************************************
   2  * RSTP library - Rapid Spanning Tree (802.1t, 802.1w)
   3  * Copyright (C) 2001-2003 Optical Access
   4  * Author: Alex Rozin
   5  *
   6  * This file is part of RSTP library.
   7  *
   8  * RSTP library is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by the
  10  * Free Software Foundation; version 2.1
  11  *
  12  * RSTP library is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public License
  18  * along with RSTP library; see the file COPYING.  If not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20  * 02111-1307, USA.
  21  **********************************************************************/
  22
  23 /* STP priority vectors API : 17.4.2 */
  24
  25 #include "base.h"
  26 #include "stp_bpdu.h"
  27 #include "vector.h"
  28
  29 int
  30 STP_VECT_compare_bridge_id (BRIDGE_ID* b1, BRIDGE_ID* b2)
  31 {
  32   if (b1->prio < b2->prio)
  33     return -1;
  34
  35   if (b1->prio > b2->prio)
  36     return 1;
  37   return memcmp (b1->addr, b2->addr, 6);
  38 }
  39
  40 void
  41 STP_VECT_copy (OUT PRIO_VECTOR_T* t, IN PRIO_VECTOR_T* f)
  42 {
  43   memcpy (t, f, sizeof (PRIO_VECTOR_T));
  44 }
  45
  46 void
  47 STP_VECT_create (OUT PRIO_VECTOR_T* t,
  48                  IN BRIDGE_ID* root_br,
  49                  IN unsigned long root_path_cost,
  50                  IN BRIDGE_ID* design_bridge,
  51                  IN PORT_ID design_port,
  52                  IN PORT_ID bridge_port)
  53 {
  54   memcpy (&t->root_bridge, root_br, sizeof (BRIDGE_ID));
  55   t->root_path_cost = root_path_cost;
  56   memcpy (&t->design_bridge, design_bridge, sizeof (BRIDGE_ID));
  57   t->design_port = design_port;
  58   t->bridge_port = bridge_port;
  59 }
  60
  61 int
  62 STP_VECT_compare_vector (PRIO_VECTOR_T* v1, PRIO_VECTOR_T* v2)
  63 {
  64   int bridcmp;
  65
  66   bridcmp = STP_VECT_compare_bridge_id (&v1->root_bridge, &v2->root_bridge);
  67   if (bridcmp < 0) return bridcmp;
  68
  69   if (! bridcmp) {
  70     bridcmp = v1->root_path_cost - v2->root_path_cost;
  71     if (bridcmp < 0) return bridcmp;
  72     if (! bridcmp) {
  73       bridcmp = STP_VECT_compare_bridge_id (&v1->design_bridge, &v2->design_bridge);
  74       if (bridcmp < 0) return bridcmp;
  75       if (! bridcmp) {
  76         bridcmp = v1->design_port - v2->design_port;
  77         if (bridcmp < 0) return bridcmp;
  78         if (! bridcmp)
  79           return v1->bridge_port - v2->bridge_port;
  80       }
  81     }
  82   }
  83
  84   return bridcmp;
  85 }
  86
  87 static unsigned short
  88 stp_vect_get_short (IN unsigned char* f)
  89 {
  90   return ntohs (*(unsigned short *)f);
  91 }
  92
  93 static void
  94 stp_vect_set_short (IN unsigned short f, OUT unsigned char* t)
  95 {
  96   *(unsigned short *)t = htons (f);
  97 }
  98
  99 static void
 100 stp_vect_get_bridge_id (IN unsigned char* c_br, OUT BRIDGE_ID* bridge_id)
 101 {
 102   bridge_id->prio = stp_vect_get_short (c_br);
 103   memcpy (bridge_id->addr, c_br + 2, 6);
 104 }
 105
 106 static void
 107 stp_vect_set_bridge_id (IN BRIDGE_ID* bridge_id, OUT unsigned char* c_br)
 108 {
 109   stp_vect_set_short (bridge_id->prio, c_br);
 110   memcpy (c_br + 2, bridge_id->addr, 6);
 111 }
 112
 113 void
 114 STP_VECT_get_vector (IN BPDU_BODY_T* b, OUT PRIO_VECTOR_T* v)
 115 {
 116   stp_vect_get_bridge_id (b->root_id, &v->root_bridge);
 117
 118   v->root_path_cost = ntohl (*((long*) b->root_path_cost));
 119
 120   stp_vect_get_bridge_id (b->bridge_id, &v->design_bridge);
 121
 122   v->design_port = stp_vect_get_short (b->port_id);
 123 }
 124
 125 void
 126 STP_VECT_set_vector (IN PRIO_VECTOR_T* v, OUT BPDU_BODY_T* b)
 127 {
 128   unsigned long root_path_cost;
 129
 130   stp_vect_set_bridge_id (&v->root_bridge, b->root_id);
 131
 132   root_path_cost = htonl (v->root_path_cost);
 133   memcpy (b->root_path_cost, &root_path_cost, 4);
 134
 135   stp_vect_set_bridge_id (&v->design_bridge, b->bridge_id);
 136
 137   stp_vect_set_short (v->design_port, b->port_id);
 138 }
 139
 140 #ifdef STP_DBG
 141
 142 void
 143 STP_VECT_br_id_print (IN char *title, IN BRIDGE_ID* br_id, IN Bool cr)
 144 {
 145   Print ("%s=%04lX-%02x%02x%02x%02x%02x%02x",
 146             title,
 147           (unsigned long) br_id->prio,
 148           (unsigned char) br_id->addr[0],
 149           (unsigned char) br_id->addr[1],
 150           (unsigned char) br_id->addr[2],
 151           (unsigned char) br_id->addr[3],
 152           (unsigned char) br_id->addr[4],
 153           (unsigned char) br_id->addr[5]);
 154   Print (cr ? "\n" : " ");
 155 }
 156
 157 void
 158 STP_VECT_print (IN char *title, IN PRIO_VECTOR_T *v)
 159 {
 160   Print ("%s:", title);
 161   STP_VECT_br_id_print ("rootBr", &v->root_bridge, False);
 162
 163 /****
 164   Print (" rpc=%ld ", (long) v->root_path_cost);
 165 ****/
 166
 167   STP_VECT_br_id_print ("designBr", &v->design_bridge, False);
 168
 169 /****/
 170   Print (" dp=%lx bp=%lx ",
 171           (unsigned long) v->design_port,
 172           (unsigned long) v->bridge_port);
 173 /***********/
 174   Print ("\n");
 175 }
 176 #endif
 177