xref: /titanic_41/usr/src/lib/librstp/common/statmch.c (revision e4d060fb4c00d44cd578713eb9a921f594b733b8)
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 
124