1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
|
/* $OpenBSD: hd_timer.c,v 1.4 2003/12/10 07:22:42 itojun Exp $ */
/* $NetBSD: hd_timer.c,v 1.6 1996/02/13 22:04:33 christos Exp $ */
/*
* Copyright (c) University of British Columbia, 1984
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Laboratory for Computation Vision and the Computer Science Department
* of the University of British Columbia.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)hd_timer.c 8.1 (Berkeley) 6/10/93
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/socket.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <netccitt/hdlc.h>
#include <netccitt/hd_var.h>
#include <netccitt/x25.h>
#include <netccitt/pk_extern.h>
/*
* these can be patched with adb if the
* default values are inappropriate
*/
int hd_t1 = T1;
int hd_t3 = T3;
int hd_n2 = N2;
/*
* HDLC TIMER
*
* This routine is called every 500ms by the kernel. Decrement timer by this
* amount - if expired then process the event.
*/
void
hd_timer()
{
struct hdcb *hdp;
int s = splimp();
for (hdp = hdcbhead; hdp; hdp = hdp->hd_next) {
if (hdp->hd_rrtimer && (--hdp->hd_rrtimer == 0)) {
if (hdp->hd_lasttxnr != hdp->hd_vr)
hd_writeinternal(hdp, RR, POLLOFF);
}
if (!(hdp->hd_timer && --hdp->hd_timer == 0))
continue;
switch (hdp->hd_state) {
case INIT:
case DISC_SENT:
hd_writeinternal(hdp, DISC, POLLON);
break;
case ABM:
if (hdp->hd_lastrxnr != hdp->hd_vs) { /* XXX */
hdp->hd_timeouts++;
hd_resend_iframe(hdp);
}
break;
case WAIT_SABM:
hd_writeinternal(hdp, FRMR, POLLOFF);
if (++hdp->hd_retxcnt == hd_n2) {
hdp->hd_retxcnt = 0;
hd_writeinternal(hdp, SABM, POLLOFF);
hdp->hd_state = WAIT_UA;
}
break;
case DM_SENT:
if (++hdp->hd_retxcnt == hd_n2) {
/* Notify the packet level. */
(void) pk_ctlinput(PRC_LINKDOWN,
(struct sockaddr *) hdp->hd_pkp, NULL);
hdp->hd_retxcnt = 0;
hdp->hd_state = SABM_SENT;
hd_writeinternal(hdp, SABM, POLLOFF);
} else
hd_writeinternal(hdp, DM, POLLOFF);
break;
case WAIT_UA:
if (++hdp->hd_retxcnt == hd_n2) {
hdp->hd_retxcnt = 0;
hd_writeinternal(hdp, DM, POLLOFF);
hdp->hd_state = DM_SENT;
} else
hd_writeinternal(hdp, SABM, POLLOFF);
break;
case SABM_SENT:
/* Do this indefinitely. */
hd_writeinternal(hdp, SABM, POLLON);
break;
case DISCONNECTED:
/*
* Poll the interface driver flags waiting
* for the IFF_UP bit to come on.
*/
if (hdp->hd_ifp->if_flags & IFF_UP)
hdp->hd_state = INIT;
}
SET_TIMER(hdp);
}
splx(s);
}
|
