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 /* Port Protocol Migration state machine : 17.26 */
24 
25 #include "base.h"
26 #include "stpm.h"
27 
28 #define STATES { \
29   CHOOSE(INIT),     \
30   CHOOSE(SEND_RSTP),    \
31   CHOOSE(SENDING_RSTP), \
32   CHOOSE(SEND_STP), \
33   CHOOSE(SENDING_STP)  \
34 }
35 
36 #define GET_STATE_NAME STP_migrate_get_state_name
37 #include "choose.h"
38 
39 #define MigrateTime 3 /* 17,16.4 */
40 
41 void
42 STP_migrate_enter_state (STATE_MACH_T* this)
43 {
44   register PORT_T*       port = this->owner.port;
45 
46   switch (this->State) {
47     case BEGIN:
48     case INIT:
49       port->initPm = True;
50       port->mcheck = False;
51       break;
52     case SEND_RSTP:
53       port->mdelayWhile = MigrateTime;
54       port->mcheck = port->initPm = False;
55       port->sendRSTP = True;
56       break;
57     case SENDING_RSTP:
58       port->rcvdRSTP = port->rcvdSTP = False;
59       break;
60     case SEND_STP:
61       port->mdelayWhile = MigrateTime;
62       port->sendRSTP = False;
63       port->initPm = False;
64       break;
65     case SENDING_STP:
66       port->rcvdRSTP = port->rcvdSTP = False;
67       break;
68   }
69 }
70 
71 Bool
72 STP_migrate_check_conditions (STATE_MACH_T* this)
73 {
74   register PORT_T*    port = this->owner.port;
75 
76   if ((!port->portEnabled && !port->initPm) || BEGIN == this->State)
77     return STP_hop_2_state (this, INIT);
78 
79   switch (this->State) {
80     case INIT:
81       if (port->portEnabled) {
82         return STP_hop_2_state (this, (port->owner->ForceVersion >= 2) ?
83                                    SEND_RSTP : SEND_STP);
84       }
85       break;
86     case SEND_RSTP:
87       return STP_hop_2_state (this, SENDING_RSTP);
88     case SENDING_RSTP:
89       if (port->mcheck)
90         return STP_hop_2_state (this, SEND_RSTP);
91       if (port->mdelayWhile &&
92           (port->rcvdSTP || port->rcvdRSTP)) {
93         return STP_hop_2_state (this, SENDING_RSTP);
94       }
95 
96       if (!port->mdelayWhile && port->rcvdSTP) {
97         return STP_hop_2_state (this, SEND_STP);
98       }
99 
100       if (port->owner->ForceVersion < 2) {
101         return STP_hop_2_state (this, SEND_STP);
102       }
103 
104       break;
105     case SEND_STP:
106       return STP_hop_2_state (this, SENDING_STP);
107     case SENDING_STP:
108       if (port->mcheck)
109         return STP_hop_2_state (this, SEND_RSTP);
110       if (port->mdelayWhile &&
111           (port->rcvdSTP || port->rcvdRSTP))
112         return STP_hop_2_state (this, SENDING_STP);
113       if (!port->mdelayWhile && port->rcvdRSTP)
114         return STP_hop_2_state (this, SEND_RSTP);
115       break;
116   }
117   return False;
118 }
119 
120