usr/src/lib/librstp/common/statmch.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 /* Generic (abstract) state machine : 17.13, 17.14 */
  24
  25 #include "base.h"
  26 #include "statmch.h"
  27 #include "stp_vectors.h"
  28
  29 #if STP_DBG
  30 #  include "stpm.h"
  31 #endif
  32
  33 STATE_MACH_T *
  34 STP_state_mach_create (void (*concreteEnterState) (STATE_MACH_T*),
  35                        Bool (*concreteCheckCondition) (STATE_MACH_T*),
  36                        char *(*concreteGetStatName) (int),
  37                        void *owner, char *name)
  38 {
  39   STATE_MACH_T *this;
  40
  41   STP_MALLOC(this, STATE_MACH_T, "state machine");
  42
  43   this->State = BEGIN;
  44   this->name = (char*) strdup (name);
  45   this->changeState = False;
  46 #if STP_DBG
  47   this->debug = False;
  48   this->ignoreHop2State = BEGIN;
  49 #endif
  50   this->concreteEnterState = concreteEnterState;
  51   this->concreteCheckCondition = concreteCheckCondition;
  52   this->concreteGetStatName = concreteGetStatName;
  53   this->owner.owner = owner;
  54
  55   return this;
  56 }
  57
  58 void
  59 STP_state_mach_delete (STATE_MACH_T *this)
  60 {
  61   free (this->name);
  62   STP_FREE(this, "state machine");
  63 }
  64
  65 Bool
  66 STP_check_condition (STATE_MACH_T* this)
  67 {
  68   Bool bret;
  69
  70   bret = (*(this->concreteCheckCondition)) (this);
  71   if (bret) {
  72     this->changeState = True;
  73   }
  74
  75   return bret;
  76 }
  77
  78 Bool
  79 STP_change_state (STATE_MACH_T* this)
  80 {
  81   register int number_of_loops;
  82
  83   for (number_of_loops = 0; ; number_of_loops++) {
  84     if (! this->changeState) break;
  85     (*(this->concreteEnterState)) (this);
  86     this->changeState = False;
  87     (void) STP_check_condition (this);
  88   }
  89
  90   return number_of_loops;
  91 }
  92
  93 Bool
  94 STP_hop_2_state (STATE_MACH_T* this, unsigned int new_state)
  95 {
  96 #ifdef STP_DBG
  97   switch (this->debug) {
  98     case 0: break;
  99     case 1:
 100       if (new_state == this->State || new_state == this->ignoreHop2State) break;
 101       stp_trace ("%-8s(%s-%s): %s=>%s",
 102         this->name,
 103         *this->owner.port->owner->name ? this->owner.port->owner->name : "Glbl",
 104         this->owner.port->port_name,
 105         (*(this->concreteGetStatName)) (this->State),
 106         (*(this->concreteGetStatName)) (new_state));
 107       break;
 108     case 2:
 109       if (new_state == this->State) break;
 110       stp_trace ("%s(%s): %s=>%s",
 111         this->name,
 112         *this->owner.stpm->name ? this->owner.stpm->name : "Glbl",
 113         (*(this->concreteGetStatName)) (this->State),
 114         (*(this->concreteGetStatName)) (new_state));
 115       break;
 116   }
 117 #endif
 118
 119   this->State = new_state;
 120   this->changeState = True;
 121   return True;
 122 }
 123