xref: /titanic_41/usr/src/lib/librstp/common/edge.c (revision c037192b037119c9fd354732fc29b38ce097d356)
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 /* Note: this state mashine distinkts from described in P802.1t Clause 18. */
24 /* I am ready to discuss it                                                */
25 
26 #include "base.h"
27 #include "stpm.h"
28 #include "stp_vectors.h"
29 
30 #define STATES {        \
31   CHOOSE(DISABLED),         \
32   CHOOSE(DETECTED),     \
33   CHOOSE(DELAYED),     \
34   CHOOSE(RESOLVED)     \
35 }
36 
37 #define GET_STATE_NAME STP_edge_get_state_name
38 #include "choose.h"
39 
40 #define DEFAULT_LINK_DELAY  3
41 
42 void
43 STP_edge_enter_state (STATE_MACH_T *s)
44 {
45   register PORT_T *port = s->owner.port;
46 
47   switch (s->State) {
48     case BEGIN:
49       break;
50     case DISABLED:
51       port->operEdge = port->adminEdge;
52       port->wasInitBpdu = False;
53       port->lnkWhile = 0;
54       port->portEnabled = False;
55       break;
56     case DETECTED:
57       port->portEnabled = True;
58       port->lnkWhile = port->LinkDelay;
59       port->operEdge = False;
60       break;
61     case DELAYED:
62       break;
63     case RESOLVED:
64       if (! port->wasInitBpdu) {
65           port->operEdge = port->adminEdge;
66       }
67       break;
68   }
69 }
70 
71 Bool
72 STP_edge_check_conditions (STATE_MACH_T *s)
73 {
74   register PORT_T *port = s->owner.port;
75 
76   /* If we're disabled, then stay that way. */
77   if (!port->adminEnable) {
78     if (s->State == DISABLED)
79       return False;
80     else
81       return STP_hop_2_state (s, DISABLED);
82   }
83 
84   switch (s->State) {
85     case BEGIN:
86       return STP_hop_2_state (s, DISABLED);
87     case DISABLED:
88       if (port->adminEnable) {
89         return STP_hop_2_state (s, DETECTED);
90       }
91       break;
92     case DETECTED:
93       return STP_hop_2_state (s, DELAYED);
94     case DELAYED:
95       if (port->wasInitBpdu) {
96 #ifdef STP_DBG
97         if (s->debug)
98             stp_trace ("port %s 'edge' resolved by BPDU", port->port_name);
99 #endif
100         return STP_hop_2_state (s, RESOLVED);
101       }
102 
103       if (! port->lnkWhile)  {
104 #ifdef STP_DBG
105         if (s->debug)
106           stp_trace ("port %s 'edge' resolved by timer", port->port_name);
107 #endif
108         return STP_hop_2_state (s, RESOLVED);
109       }
110       break;
111     case RESOLVED:
112       break;
113   }
114   return False;
115 }
116