src/hardware/serialport/nullmodem.h

/*
 *  Copyright (C) 2002-2020  The DOSBox Team
 *
 *  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.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */


// include guard
#ifndef DOSBOX_NULLMODEM_WIN32_H
#define DOSBOX_NULLMODEM_WIN32_H

#include "dosbox.h"

#if C_MODEM

#include "misc_util.h"
#include "serialport.h"

#define SERIAL_SERVER_POLLING_EVENT     SERIAL_BASE_EVENT_COUNT+1
#define SERIAL_TX_REDUCTION             SERIAL_BASE_EVENT_COUNT+2
#define SERIAL_NULLMODEM_DTR_EVENT      SERIAL_BASE_EVENT_COUNT+3
#define SERIAL_NULLMODEM_EVENT_COUNT    SERIAL_BASE_EVENT_COUNT+3

class CNullModem : public CSerial {
public:
        CNullModem(Bitu id, CommandLine* cmd);
        ~CNullModem();

        void updatePortConfig(Bit16u divider, Bit8u lcr);
        void updateMSR();
        void transmitByte(Bit8u val, bool first);
        void setBreak(bool value);
        
        void setRTSDTR(bool rts, bool dtr);
        void setRTS(bool val);
        void setDTR(bool val);
        void handleUpperEvent(Bit16u type);

private:
        TCPServerSocket* serversocket;
        TCPClientSocket* clientsocket;

        bool receiveblock;              // It's not a block of data it rather blocks
        Bit16u serverport;              // we are a server if this is nonzero
        Bit16u clientport;

        Bit8u hostnamebuffer[128]; // the name passed to us by the user

        Bitu rx_state;
#define N_RX_IDLE               0
#define N_RX_WAIT               1
#define N_RX_BLOCKED    2
#define N_RX_FASTWAIT   3
#define N_RX_DISC               4

        bool doReceive();
        bool ClientConnect(TCPClientSocket* newsocket);
        bool ServerListen();
        bool ServerConnect();
    void Disconnect();
        Bits readChar();
        void WriteChar(Bit8u data);

        bool DTR_delta;         // with dtrrespect, we try to establish a connection
                                                // whenever DTR switches to 1. This variable is
                                                // used to remember the old state.

        bool tx_block;          // true while the SERIAL_TX_REDUCTION event
                                                // is pending

        Bitu rx_retry;          // counter of retries

        Bitu rx_retry_max;      // how many POLL_EVENTS to wait before causing
                                                // a overrun error.

        Bitu tx_gather;         // how long to gather tx data before
                                                // sending all of them [milliseconds]

        
        bool dtrrespect;        // dtr behavior - only send data to the serial
                                                // port when DTR is on

        bool transparent;       // if true, don't send 0xff 0xXX to toggle
                                                // DSR/CTS.

        bool telnet;            // Do Telnet parsing.

    bool nonlocal;      // Enable connections NOT originating from localhost

        // Telnet's brain
#define TEL_CLIENT 0
#define TEL_SERVER 1

        Bits TelnetEmulation(Bit8u data);

        // Telnet's memory
        struct {
                bool binary[2];
                bool echo[2];
                bool supressGA[2];
                bool timingMark[2];
                                        
                bool inIAC;
                bool recCommand;
                Bit8u command;
        } telClient;
};

#endif  // C_MODEM
#endif  // include guard