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/* $OpenBSD: hd_timer.c,v 1.3 2003/06/02 23:28:13 millert 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()
{
register struct hdcb *hdp;
register 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);
}
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