statmch.c revision 10491:8893b747ecdf 
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
33STATE_MACH_T *
34STP_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
58void
59STP_state_mach_delete (STATE_MACH_T *this)
60{
61  free (this->name);
62  STP_FREE(this, "state machine");
63}
64
65Bool
66STP_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
78Bool
79STP_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
93Bool
94STP_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
124