NetBSD/sys/netccitt/pk_output.c

220 lines
6.2 KiB
C

/* $NetBSD: pk_output.c,v 1.8 1996/10/10 23:02:28 christos Exp $ */
/*
* Copyright(c) University of British Columbia, 1984
* Copyright(C) Computer Science Department IV,
* University of Erlangen-Nuremberg, Germany, 1992
* Copyright(c) 1991, 1992, 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 the University of British Columbia and the Computer Science
* Department(IV) of the University of Erlangen-Nuremberg, Germany.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* @(#)pk_output.c 8.1(Berkeley) 6/10/93
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <net/if.h>
#include <netccitt/x25.h>
#include <netccitt/pk.h>
#include <netccitt/pk_var.h>
#include <netccitt/pk_extern.h>
struct mbuf_cache pk_output_cache = {0}, pk_input_cache;
void
pk_output(lcp)
register struct pklcd *lcp;
{
register struct x25_packet *xp;
register struct mbuf *m;
register struct pkcb *pkp = lcp->lcd_pkp;
if (lcp == 0 || pkp == 0) {
kprintf("pk_output: zero arg\n");
return;
}
while ((m = nextpk(lcp)) != NULL) {
xp = mtod(m, struct x25_packet *);
switch (pk_decode(xp) + lcp->lcd_state) {
/*
* All the work is already done - just set the state
* and pass to peer.
*/
case PK_CALL + READY:
lcp->lcd_state = SENT_CALL;
lcp->lcd_timer = pk_t21;
break;
/*
* Just set the state to allow packet to flow and send the
* confirmation.
*/
case PK_CALL_ACCEPTED + RECEIVED_CALL:
lcp->lcd_state = DATA_TRANSFER;
break;
/*
* Just set the state. Keep the LCD around till the
* clear confirmation is returned.
*/
case PK_CLEAR + RECEIVED_CALL:
case PK_CLEAR + SENT_CALL:
case PK_CLEAR + DATA_TRANSFER:
lcp->lcd_state = SENT_CLEAR;
lcp->lcd_retry = 0;
/* fall through */
case PK_CLEAR + SENT_CLEAR:
lcp->lcd_timer = pk_t23;
lcp->lcd_retry++;
break;
case PK_CLEAR_CONF + RECEIVED_CLEAR:
case PK_CLEAR_CONF + SENT_CLEAR:
case PK_CLEAR_CONF + READY:
lcp->lcd_state = READY;
break;
case PK_DATA + DATA_TRANSFER:
SPS(xp, lcp->lcd_ssn);
lcp->lcd_input_window =
(lcp->lcd_rsn + 1) % MODULUS;
SPR(xp, lcp->lcd_input_window);
lcp->lcd_last_transmitted_pr = lcp->lcd_input_window;
lcp->lcd_ssn = (lcp->lcd_ssn + 1) % MODULUS;
if (lcp->lcd_ssn == ((lcp->lcd_output_window + lcp->lcd_windowsize) % MODULUS))
lcp->lcd_window_condition = TRUE;
break;
case PK_INTERRUPT + DATA_TRANSFER:
#ifdef ancient_history
xp->packet_data = 0;
#endif
lcp->lcd_intrconf_pending = TRUE;
break;
case PK_INTERRUPT_CONF + DATA_TRANSFER:
break;
case PK_RR + DATA_TRANSFER:
case PK_RNR + DATA_TRANSFER:
lcp->lcd_input_window =
(lcp->lcd_rsn + 1) % MODULUS;
SPR(xp, lcp->lcd_input_window);
lcp->lcd_last_transmitted_pr = lcp->lcd_input_window;
break;
case PK_RESET + DATA_TRANSFER:
lcp->lcd_reset_condition = TRUE;
break;
case PK_RESET_CONF + DATA_TRANSFER:
lcp->lcd_reset_condition = FALSE;
break;
/*
* A restart should be only generated internally.
* Therefore all logic for restart is in the
* pk_restart routine.
*/
case PK_RESTART + READY:
lcp->lcd_timer = pk_t20;
break;
/*
* Restarts are all handled internally. Therefore
* all the logic for the incoming restart packet is
* handled in the pk_input routine.
*/
case PK_RESTART_CONF + READY:
break;
default:
m_freem(m);
return;
}
/* Trace the packet. */
pk_trace(pkp->pk_xcp, m, "P-Out");
/* Pass the packet on down to the link layer */
if (pk_input_cache.mbc_size || pk_input_cache.mbc_oldsize) {
m->m_flags |= 0x08;
mbuf_cache(&pk_input_cache, m);
}
(*pkp->pk_lloutput) (m, pkp->pk_llnext, pkp->pk_rt);
}
}
/*
* This procedure returns the next packet to send or null. A packet is
* composed of one or more mbufs.
*/
struct mbuf *
nextpk(lcp)
struct pklcd *lcp;
{
register struct mbuf *m, *n;
struct socket *so = lcp->lcd_so;
register struct sockbuf *sb = (so ? &so->so_snd : &lcp->lcd_sb);
if (lcp->lcd_template) {
m = lcp->lcd_template;
lcp->lcd_template = NULL;
} else {
if (lcp->lcd_rnr_condition || lcp->lcd_window_condition ||
lcp->lcd_reset_condition)
return (NULL);
if ((m = sb->sb_mb) == 0)
return (NULL);
sb->sb_mb = m->m_nextpkt;
m->m_act = 0;
for (n = m; n; n = n->m_next)
sbfree(sb, n);
}
return (m);
}