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//
// PLP - An implementation of the PSION link protocol
//
// Copyright (C) 1999 Philip Proudman
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// e-mail philip.proudman@btinternet.com
#include <stream.h>
#include <stdlib.h>
#include <stdio.h>
#include "defs.h"
#include "bool.h"
#include "link.h"
#include "packet.h"
#include "bufferstore.h"
#include "bufferarray.h"
link::link(const char *fname, int baud, IOWatch & iow, bool _s5, bool _verbose):
s5(_s5)
{
p = new packet(fname, baud, iow, PACKET_LAYER_DIAGNOSTICS);
verbose = _verbose;
idSent = 0;
idLastGot = -1;
newLink = true;
somethingToSend = false;
timesSent = 0;
failed = false;
}
link::~link()
{
delete p;
}
void link::
send(const bufferStore & buff)
{
if (buff.getLen() > 300)
failed = true;
else
sendQueue.pushBuffer(buff);
}
bufferArray link::
poll()
{
bufferArray ret;
bufferStore buff;
unsigned char type;
while (p->get(type, buff)) {
if ((type & 0xf0) == 0x30) {
// Data
int ser = type & 0x0f;
if (verbose)
cout << "link: Got data ser " << ser << " : " << buff << endl;
// Send ack
if (idLastGot != ser) {
idLastGot = ser;
ret.pushBuffer(buff);
} else {
if (verbose)
cout << "link: Duplicated data - not passing back, repeating ack\n";
}
if (verbose)
cout << "link: Send ack ser " << ser << endl;
bufferStore blank;
p->send(ser, blank);
break;
} else if ((type & 0xf0) == 0x00) {
// Ack
int ser = type & 0x0f;
if (ser == idSent) {
if (verbose)
cout << "link: Got ack " << ser << " : " << buff << endl;
somethingToSend = false;
timesSent = 0;
}
} else if ((type & 0xf0) == 0x20) {
// New link
int ser = type & 0x0f;
if (verbose)
cout << "link: got New link request " << ser << " : " << buff << endl;
idLastGot = 0;
bufferStore blank;
if (verbose)
cout << "link: Sending ack of new link\n";
somethingToSend = false;
p->send(idLastGot, blank);
} else if ((type & 0xf0) == 0x10) {
// Disconnect
cerr << "Disconnect?\n";
failed = true;
return ret;
}
}
if (!somethingToSend) {
countToResend = 0;
if (newLink) {
somethingToSend = true;
toSend.init();
newLink = false;
idSent = 0;
} else {
if (!sendQueue.empty()) {
somethingToSend = true;
toSend = sendQueue.popBuffer();
idSent++;
if (idSent > 7)
idSent = 0;
}
}
}
if (somethingToSend) {
if (countToResend == 0) {
timesSent++;
if (timesSent == 5) {
failed = true;
} else {
if (toSend.empty()) {
// Request for new link
if (verbose)
cout << "link: Send req new session ser " << idSent << endl;
p->send(0x20 + idSent, toSend);
} else {
if (verbose)
cout << "link: Send data packet ser " << idSent << " : " << toSend << endl;
p->send(0x30 + idSent, toSend);
}
countToResend = 5;
}
} else {
countToResend--;
}
}
return ret;
}
bool link::
stuffToSend()
{
return (somethingToSend || !sendQueue.empty());
}
bool link::
hasFailed()
{
return failed;
}
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