teraterm/teraterm/commlib.c

/* Tera Term
 Copyright(C) 1994-1998 T. Teranishi
 All rights reserved. */
/* IPv6 modification is Copyright (C) 2000, 2001 Jun-ya KATO <kato@win6.jp> */

/* TERATERM.EXE, Communication routines */
#include "teraterm.h"
#include "tttypes.h"
#include "tt_res.h"
#include <process.h>

#include "ttcommon.h"
#include "ttwsk.h"
#include "ttlib.h"
#include "ttfileio.h"
#include "ttplug.h" /* TTPLUG */

#include "commlib.h"
#ifndef NO_INET6
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdio.h> /* for _snprintf() */
#include "WSAAsyncGetAddrInfo.h"
#endif /* NO_INET6 */
#include <time.h>

static SOCKET OpenSocket(PComVar);
static void AsyncConnect(PComVar);
static int CloseSocket(SOCKET);

/* create socket */
static SOCKET OpenSocket(PComVar cv)
{
        cv->s = cv->res->ai_family;
        cv->s = Psocket(cv->res->ai_family, cv->res->ai_socktype, cv->res->ai_protocol);
        return cv->s;
}

/* connect with asynchronous mode */
static void AsyncConnect(PComVar cv)
{
        int Err;
        BOOL BBuf;
        BBuf = TRUE;
        /* set synchronous mode */
        PWSAAsyncSelect(cv->s,cv->HWin,0,0);
        Psetsockopt(cv->s,(int)SOL_SOCKET,SO_OOBINLINE,(char FAR *)&BBuf,sizeof(BBuf));
        /* set asynchronous mode */
        PWSAAsyncSelect(cv->s,cv->HWin,WM_USER_COMMOPEN, FD_CONNECT);

        // �z�X�g���������������������������A�����I���\�P�b�g���N���[�Y�����A
        // �����������L�����Z���������B�l��0�������������������B
        // (2007.1.11 yutaka)
        if (*cv->ConnetingTimeout > 0) {
                SetTimer(cv->HWin, IdCancelConnectTimer, *cv->ConnetingTimeout * 1000, NULL);
        }

        /* WM_USER_COMMOPEN occurs, CommOpen is called, then CommStart is called */
        Err = Pconnect(cv->s, cv->res->ai_addr, cv->res->ai_addrlen);
        if (Err != 0) {
                Err = PWSAGetLastError();
                if (Err == WSAEWOULDBLOCK)  {
                        /* Do nothing */
                } else if (Err!=0 ) {
                        PostMessage(cv->HWin, WM_USER_COMMOPEN,0,
                                    MAKELONG(FD_CONNECT,Err));
                }
        }
}

/* close socket */
static int CloseSocket(SOCKET s)
{
        return Pclosesocket(s);
}

#define CommInQueSize 8192
#define CommOutQueSize 2048
#define CommXonLim 2048
#define CommXoffLim 2048

#define READENDNAME "ReadEnd"
#define WRITENAME "Write"
#define READNAME "Read"
#define PRNWRITENAME "PrnWrite"

static HANDLE ReadEnd;
static OVERLAPPED wol, rol;

// Winsock async operation handle
static HANDLE HAsync=0;

BOOL TCPIPClosed = TRUE;

/* Printer port handle for
   direct pass-thru printing */
static HANDLE PrnID = INVALID_HANDLE_VALUE;
static BOOL LPTFlag;

// Initialize ComVar.
// This routine is called only once
// by the initialization procedure of Tera Term.
void CommInit(PComVar cv)
{
        cv->Open = FALSE;
        cv->Ready = FALSE;

// log-buffer variables
        cv->HLogBuf = 0;
        cv->HBinBuf = 0;
        cv->LogBuf = NULL;
        cv->BinBuf = NULL;
        cv->LogPtr = 0;
        cv->LStart = 0;
        cv->LCount = 0;
        cv->BinPtr = 0;
        cv->BStart = 0;
        cv->BCount = 0;
        cv->DStart = 0;
        cv->DCount = 0;
        cv->BinSkip = 0;
        cv->FilePause = 0;
        cv->ProtoFlag = FALSE;
/* message flag */
        cv->NoMsg = 0;
}

/* reset a serial port which is already open */
void CommResetSerial(PTTSet ts, PComVar cv, BOOL ClearBuff)
{
        DCB dcb;
        DWORD DErr;
        COMMTIMEOUTS ctmo;

        if (! cv->Open ||
                (cv->PortType != IdSerial)) {
                        return;
        }

        ClearCommError(cv->ComID,&DErr,NULL);
        SetupComm(cv->ComID,CommInQueSize,CommOutQueSize);
        /* flush input and output buffers */
        if (ClearBuff) {
                PurgeComm(cv->ComID, PURGE_TXABORT | PURGE_RXABORT |
                                     PURGE_TXCLEAR | PURGE_RXCLEAR);
        }

        memset(&ctmo,0,sizeof(ctmo));
        ctmo.ReadIntervalTimeout = MAXDWORD;
        ctmo.WriteTotalTimeoutConstant = 500;
        SetCommTimeouts(cv->ComID,&ctmo);
        cv->InBuffCount = 0;
        cv->InPtr = 0;
        cv->OutBuffCount = 0;
        cv->OutPtr = 0;

        cv->DelayPerChar = ts->DelayPerChar;
        cv->DelayPerLine = ts->DelayPerLine;

        memset(&dcb,0,sizeof(DCB));
        dcb.DCBlength = sizeof(DCB);
        dcb.BaudRate = ts->Baud;
        dcb.fBinary = TRUE;
        switch (ts->Parity) {
                case IdParityEven:
                        dcb.fParity = TRUE;
                        dcb.Parity = EVENPARITY;
                        break;
                case IdParityOdd:
                        dcb.fParity = TRUE;
                        dcb.Parity = ODDPARITY;
                        break;
                case IdParityNone:
                        dcb.Parity = NOPARITY;
                        break;
        }

        dcb.fDtrControl = DTR_CONTROL_ENABLE;
        dcb.fRtsControl = RTS_CONTROL_ENABLE;
        switch (ts->Flow) {
                case IdFlowX:
                        dcb.fOutX = TRUE;
                        dcb.fInX = TRUE;
                        dcb.XonLim = CommXonLim;
                        dcb.XoffLim = CommXoffLim;
                        dcb.XonChar = XON;
                        dcb.XoffChar = XOFF;
                        break;
                case IdFlowHard:
                        dcb.fOutxCtsFlow = TRUE;
                        dcb.fRtsControl = RTS_CONTROL_HANDSHAKE;
                        break;
        }

        switch (ts->DataBit) {
                case IdDataBit7:
                        dcb.ByteSize = 7;
                        break;
                case IdDataBit8:
                        dcb.ByteSize = 8;
                        break;
        }
        switch (ts->StopBit) {
                case IdStopBit1:
                        dcb.StopBits = ONESTOPBIT;
                        break;
                case IdStopBit2:
                        dcb.StopBits = TWOSTOPBITS;
                        break;
        }

        SetCommState(cv->ComID, &dcb);

        /* enable receive request */
        SetCommMask(cv->ComID,0);
        SetCommMask(cv->ComID,EV_RXCHAR);
}

void CommOpen(HWND HW, PTTSet ts, PComVar cv)
{
#ifdef NO_INET6
        int Err;
#endif /* NO_INET6 */
        char ErrMsg[21];
        char P[50];

        MSG Msg;
#ifndef NO_INET6
        ADDRINFO hints;
        char pname[NI_MAXSERV];
#else
        char HEntBuff[MAXGETHOSTSTRUCT];
        u_long addr;
        SOCKADDR_IN saddr;
#endif /* NO_INET6 */

        BOOL InvalidHost;
#ifdef NO_INET6
        BOOL BBuf;
#endif /* NO_INET6 */

        char uimsg[MAX_UIMSG];

        /* initialize ComVar */
        cv->InBuffCount = 0;
        cv->InPtr = 0;
        cv->OutBuffCount = 0;
        cv->OutPtr = 0;
        cv->HWin = HW;
        cv->Ready = FALSE;
        cv->Open = FALSE;
        cv->PortType = ts->PortType;
        cv->ComPort = 0;
        cv->RetryCount = 0;
#ifndef NO_INET6
        cv->RetryWithOtherProtocol = TRUE;
#endif /* NO_INET6 */
        cv->s = INVALID_SOCKET;
        cv->ComID = INVALID_HANDLE_VALUE;
        cv->CanSend = TRUE;
        cv->RRQ = FALSE;
        cv->SendKanjiFlag = FALSE;
        cv->SendCode = IdASCII;
        cv->EchoKanjiFlag = FALSE;
        cv->EchoCode = IdASCII;
        cv->Language = ts->Language;
        cv->CRSend = ts->CRSend;
        cv->KanjiCodeEcho = ts->KanjiCode;
        cv->JIS7KatakanaEcho = ts->JIS7Katakana;
        cv->KanjiCodeSend = ts->KanjiCodeSend;
        cv->JIS7KatakanaSend = ts->JIS7KatakanaSend;
        cv->KanjiIn = ts->KanjiIn;
        cv->KanjiOut = ts->KanjiOut;
        cv->RussHost = ts->RussHost;
        cv->RussClient = ts->RussClient;
        cv->DelayFlag = TRUE;
        cv->DelayPerChar = ts->DelayPerChar;
        cv->DelayPerLine = ts->DelayPerLine;
        cv->TelBinRecv = FALSE;
        cv->TelBinSend = FALSE;
        cv->TelFlag = FALSE;
        cv->TelMode = FALSE;
        cv->IACFlag = FALSE;
        cv->TelCRFlag = FALSE;
        cv->TelCRSend = FALSE;
        cv->TelCRSendEcho = FALSE;
        cv->TelAutoDetect = ts->TelAutoDetect; /* TTPLUG */
        cv->Locale = ts->Locale;
        cv->CodePage = &ts->CodePage;
        cv->ConnetingTimeout = &ts->ConnectingTimeout;
        cv->LastSendTime = time(NULL);
        cv->LineModeBuffCount = 0;
        cv->Flush = FALSE;
        cv->FlushLen = 0;
        cv->TelLineMode = FALSE;

        if ((ts->PortType!=IdSerial) && (strlen(ts->HostName)==0))
        {
                PostMessage(cv->HWin, WM_USER_COMMNOTIFY, 0, FD_CLOSE);
                return;
        }

        switch (ts->PortType) {
                case IdTCPIP:
                        cv->TelFlag = (ts->Telnet > 0);
                        if (ts->EnableLineMode) {
                                cv->TelLineMode = TRUE;
                        }
                        if (! LoadWinsock()) {
                                if (cv->NoMsg==0) {
                                        get_lang_msg("MSG_TT_ERROR", uimsg, sizeof(uimsg), "Tera Term: Error", ts->UILanguageFile);
                                        get_lang_msg("MSG_WINSOCK_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Cannot use winsock", ts->UILanguageFile);
                                        MessageBox(cv->HWin,ts->UIMsg,uimsg,MB_TASKMODAL | MB_ICONEXCLAMATION);
                                }
                                InvalidHost = TRUE;
                        }
                        else {
                                TTXOpenTCP(); /* TTPLUG */
                                cv->Open = TRUE;
#ifndef NO_INET6
                                /* resolving address */
                                memset(&hints, 0, sizeof(hints));
                                hints.ai_family = ts->ProtocolFamily;
                                hints.ai_socktype = SOCK_STREAM;
                                hints.ai_protocol = IPPROTO_TCP;
                                _snprintf_s(pname, sizeof(pname), _TRUNCATE, "%d", ts->TCPPort);

                                HAsync = WSAAsyncGetAddrInfo(HW, WM_USER_GETHOST,
                                                             ts->HostName, pname, &hints, &cv->res0);
                                if (HAsync == 0)
                                        InvalidHost = TRUE;
                                else {
                                        cv->ComPort = 1; // set "getting host" flag
                                                         //  (see CVTWindow::OnSysCommand())
                                        do {
                                                if (GetMessage(&Msg,0,0,0)) {
                                                        if ((Msg.hwnd==HW) &&
                                                            ((Msg.message == WM_SYSCOMMAND) &&
                                                             ((Msg.wParam & 0xfff0) == SC_CLOSE) ||
                                                             (Msg.message == WM_COMMAND) &&
                                                             (LOWORD(Msg.wParam) == ID_FILE_EXIT) ||
                                                             (Msg.message == WM_CLOSE))) { /* Exit when the user closes Tera Term */
                                                                PWSACancelAsyncRequest(HAsync);
                                                                CloseHandle(HAsync);
                                                                HAsync = 0;
                                                                cv->ComPort = 0; // clear "getting host" flag
                                                                PostMessage(HW,Msg.message,Msg.wParam,Msg.lParam);
                                                                return;
                                                        }
                                                        if (Msg.message != WM_USER_GETHOST) { /* Prosess messages */
                                                                TranslateMessage(&Msg);
                                                                DispatchMessage(&Msg);
                                                        }
                                                }
                                                else {
                                                        return;
                                                }
                                        } while (Msg.message!=WM_USER_GETHOST);
                                        cv->ComPort = 0; // clear "getting host" flag
                                        CloseHandle(HAsync);
                                        HAsync = 0;
                                        InvalidHost = WSAGETASYNCERROR(Msg.lParam) != 0;
                                }
                        } /* if (!LoadWinsock()) */

                        if (InvalidHost) {
                                if (cv->NoMsg==0) {
                                        get_lang_msg("MSG_TT_ERROR", uimsg, sizeof(uimsg), "Tera Term: Error", ts->UILanguageFile);
                                        get_lang_msg("MSG_INVALID_HOST_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Invalid host", ts->UILanguageFile);
                                        MessageBox(cv->HWin,ts->UIMsg,uimsg,MB_TASKMODAL | MB_ICONEXCLAMATION);
                                }
                                goto BreakSC;
                        }
                        for (cv->res = cv->res0; cv->res; cv->res = cv->res->ai_next) {
                                cv->s =  OpenSocket(cv);
                                if (cv->s == INVALID_SOCKET) {
                                        CloseSocket(cv->s);
                                        continue;
                                }
                                /* start asynchronous connect */
                                AsyncConnect(cv);
                                break; /* break for-loop immediately */
                        }
                        break;
#else
        if ((ts->HostName[0] >= 0x30) && (ts->HostName[0] <= 0x39))
        {
          addr = Pinet_addr(ts->HostName);
          InvalidHost = (addr == 0xffffffff);
        }
        else {
          HAsync = PWSAAsyncGetHostByName(HW,WM_USER_GETHOST,
          ts->HostName,HEntBuff,sizeof(HEntBuff));
          if (HAsync == 0)
            InvalidHost = TRUE;
          else {
            cv->ComPort = 1; // set "getting host" flag
                             //  (see CVTWindow::OnSysCommand())
            do {
              if (GetMessage(&Msg,0,0,0))
              {
                if ((Msg.hwnd==HW) &&
                    ((Msg.message == WM_SYSCOMMAND) &&
                     ((Msg.wParam & 0xfff0) == SC_CLOSE) ||
                     (Msg.message == WM_COMMAND) &&
                     (LOWORD(Msg.wParam) == ID_FILE_EXIT) ||
                     (Msg.message == WM_CLOSE)))
                { /* Exit when the user closes Tera Term */
                  PWSACancelAsyncRequest(HAsync);
                  HAsync = 0;
                  cv->ComPort = 0; // clear "getting host" flag
                  PostMessage(HW,Msg.message,Msg.wParam,Msg.lParam);
                  return;
                }
                if (Msg.message != WM_USER_GETHOST)
                { /* Prosess messages */
                  TranslateMessage(&Msg);
                  DispatchMessage(&Msg);
                }
              }
              else {
                return;
              }
            } while (Msg.message!=WM_USER_GETHOST);
            cv->ComPort = 0; // clear "getting host" flag
            HAsync = 0;
            InvalidHost = WSAGETASYNCERROR(Msg.lParam) != 0;
            if (! InvalidHost)
            {
              if (((PHOSTENT)HEntBuff)->h_addr_list != NULL)
                memcpy(&addr,
                  ((PHOSTENT)HEntBuff)->h_addr_list[0],sizeof(addr));
              else
                InvalidHost = TRUE;
            }
          }

        }

        if (InvalidHost)
        {
          if (cv->NoMsg==0)
            MessageBox(cv->HWin,"Invalid host",ErrorCaption,
              MB_TASKMODAL | MB_ICONEXCLAMATION);
        }
        else {
          cv->s= Psocket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
          if (cv->s==INVALID_SOCKET)
          {
            InvalidHost = TRUE;
            if (cv->NoMsg==0)
              MessageBox(cv->HWin,ErrorCantConn,ErrorCaption,
                MB_TASKMODAL | MB_ICONEXCLAMATION);
          }
          else {
            BBuf = TRUE;
            Psetsockopt(cv->s,(int)SOL_SOCKET,SO_OOBINLINE,(char FAR *)&BBuf,sizeof(BBuf));

            PWSAAsyncSelect(cv->s,cv->HWin,WM_USER_COMMOPEN, FD_CONNECT);
            saddr.sin_family = AF_INET;
            saddr.sin_port = Phtons(ts->TCPPort);
            saddr.sin_addr.s_addr = addr;
            memset(saddr.sin_zero,0,8);

            Err = Pconnect(cv->s,(LPSOCKADDR)&saddr,sizeof(saddr));
            if (Err!=0 ) Err = PWSAGetLastError();
            if (Err==WSAEWOULDBLOCK )
            {
              /* Do nothing */
            }
            else if (Err!=0 )
              PostMessage(cv->HWin, WM_USER_COMMOPEN,0,
                          MAKELONG(FD_CONNECT,Err));
          }
        }
      }
      break;
#endif /* NO_INET6 */

                case IdSerial:
                        InitFileIO(IdSerial);  /* TTPLUG */
                        TTXOpenFile(); /* TTPLUG */
                        _snprintf_s(P, sizeof(P), _TRUNCATE, "COM%d", ts->ComPort);
                        strncpy_s(ErrMsg, sizeof(ErrMsg),P, _TRUNCATE);
                        strncpy_s(P, sizeof(P),"\\\\.\\", _TRUNCATE);
                        strncat_s(P, sizeof(P),ErrMsg, _TRUNCATE);
                        cv->ComID =
                        PCreateFile(P,GENERIC_READ | GENERIC_WRITE,
                                    0,NULL,OPEN_EXISTING,
                                    FILE_FLAG_OVERLAPPED,NULL);
                        if (cv->ComID == INVALID_HANDLE_VALUE ) {
                                get_lang_msg("MSG_CANTOEPN_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Cannot open %s", ts->UILanguageFile);
                                _snprintf_s(ErrMsg, sizeof(ErrMsg), _TRUNCATE, ts->UIMsg, &P[4]);

                                if (cv->NoMsg==0) {
                                        get_lang_msg("MSG_TT_ERROR", uimsg, sizeof(uimsg), "Tera Term: Error", ts->UILanguageFile);
                                        MessageBox(cv->HWin,ErrMsg,uimsg,MB_TASKMODAL | MB_ICONEXCLAMATION);
                                }
                                InvalidHost = TRUE;
                        }
                        else {
                                cv->Open = TRUE;
                                cv->ComPort = ts->ComPort;
                                CommResetSerial(ts, cv, ts->ClearComBuffOnOpen);
                                if (!ts->ClearComBuffOnOpen) {
                                        cv->RRQ = TRUE;
                                }

                                /* notify to VT window that Comm Port is open */
                                PostMessage(cv->HWin, WM_USER_COMMOPEN, 0, 0);
                                InvalidHost = FALSE;

                                SetCOMFlag(ts->ComPort);
                        }
                        break; /* end of "case IdSerial:" */

                case IdFile:
                        InitFileIO(IdFile);  /* TTPLUG */
                        TTXOpenFile(); /* TTPLUG */
                        cv->ComID = PCreateFile(ts->HostName,GENERIC_READ,0,NULL,
                                                OPEN_EXISTING,0,NULL);
                        InvalidHost = (cv->ComID == INVALID_HANDLE_VALUE);
                        if (InvalidHost) {
                                if (cv->NoMsg==0) {
                                        get_lang_msg("MSG_TT_ERROR", uimsg, sizeof(uimsg), "Tera Term: Error", ts->UILanguageFile);
                                        get_lang_msg("MSG_CANTOEPN_FILE_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Cannot open file", ts->UILanguageFile);
                                        MessageBox(cv->HWin,ts->UIMsg,uimsg,MB_TASKMODAL | MB_ICONEXCLAMATION);
                                }
                        }
                        else {
                                cv->Open = TRUE;
                                PostMessage(cv->HWin, WM_USER_COMMOPEN, 0, 0);
                        }
                        break;
        } /* end of "switch" */

#ifndef NO_INET6
BreakSC:
#endif /* NO_INET6 */
        if (InvalidHost) {
                PostMessage(cv->HWin, WM_USER_COMMNOTIFY, 0, FD_CLOSE);
                if ( (ts->PortType==IdTCPIP) && cv->Open ) {
                        if ( cv->s!=INVALID_SOCKET ) {
                                Pclosesocket(cv->s);
                        }
                        FreeWinsock();
                }
                return;
        }
}

void CommThread(void *arg)
{
        DWORD Evt;
        PComVar cv = (PComVar)arg;
        DWORD DErr;
        HANDLE REnd;
        char Temp[20];

        _snprintf_s(Temp, sizeof(Temp), _TRUNCATE, "%s%d", READENDNAME, cv->ComPort);
        REnd = OpenEvent(EVENT_ALL_ACCESS,FALSE, Temp);
        while (TRUE) {
                if (WaitCommEvent(cv->ComID,&Evt,NULL)) {
                        if (! cv->Ready) {
                                _endthread();
                        }
                        if (! cv->RRQ) {
                                PostMessage(cv->HWin, WM_USER_COMMNOTIFY, 0, FD_READ);
                        }
                        WaitForSingleObject(REnd,INFINITE);
                }
                else {
                        DErr = GetLastError();  // this returns 995 (operation aborted) if a USB com port is removed
                        if (! cv->Ready || ERROR_OPERATION_ABORTED == DErr) {
                                _endthread();
                        }
                        ClearCommError(cv->ComID,&DErr,NULL);
                }
        }
}

void CommStart(PComVar cv, LONG lParam, PTTSet ts)
{
        char ErrMsg[31];
        char Temp[20];
        char uimsg[MAX_UIMSG];

        if (! cv->Open ) {
                return;
        }
        if ( cv->Ready ) {
                return;
        }

        // �L�����Z���^�C�}�����������������B�������A�������_�� WM_TIMER �����������������\���������B
        if (*cv->ConnetingTimeout > 0) {
                KillTimer(cv->HWin, IdCancelConnectTimer);
        }

        switch (cv->PortType) {
                case IdTCPIP:
                        ErrMsg[0] = 0;
                        switch (HIWORD(lParam)) {
                                case WSAECONNREFUSED:
                                        get_lang_msg("MSG_COMM_REFUSE_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Connection refused", ts->UILanguageFile);
                                        _snprintf_s(ErrMsg, sizeof(ErrMsg), _TRUNCATE, "%s", ts->UIMsg);
                                        break;
                                case WSAENETUNREACH:
                                        get_lang_msg("MSG_COMM_REACH_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Network cannot be reached", ts->UILanguageFile);
                                        _snprintf_s(ErrMsg, sizeof(ErrMsg), _TRUNCATE, "%s", ts->UIMsg);
                                        break;
                                case WSAETIMEDOUT:
                                        get_lang_msg("MSG_COMM_CONNECT_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Connection timed out", ts->UILanguageFile);
                                        _snprintf_s(ErrMsg, sizeof(ErrMsg), _TRUNCATE, "%s", ts->UIMsg);
                                        break;
                                default:
                                        get_lang_msg("MSG_COMM_TIMEOUT_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Cannot connect the host", ts->UILanguageFile);
                                        _snprintf_s(ErrMsg, sizeof(ErrMsg), _TRUNCATE, "%s", ts->UIMsg);
                        }
                        if (HIWORD(lParam)>0) {
#ifndef NO_INET6
                                /* connect() failed */
                                if (cv->res->ai_next != NULL) {
                                        /* try to connect with other protocol */
                                        CloseSocket(cv->s);
                                        for (cv->res = cv->res->ai_next; cv->res; cv->res = cv->res->ai_next) {
                                                cv->s = OpenSocket(cv);
                                                if (cv->s == INVALID_SOCKET) {
                                                        CloseSocket(cv->s);
                                                        continue;
                                                }
                                                AsyncConnect(cv);
                                                cv->Ready = FALSE;
                                                cv->RetryWithOtherProtocol = TRUE; /* retry with other procotol */
                                                return;
                                        }
                                } else {
                                        /* trying with all protocol family are failed */
                                        if (cv->NoMsg==0)
                                        {
                                                get_lang_msg("MSG_TT_ERROR", uimsg, sizeof(uimsg), "Tera Term: Error", ts->UILanguageFile);
                                                MessageBox(cv->HWin,ErrMsg,uimsg,MB_TASKMODAL | MB_ICONEXCLAMATION);
                                        }
                                        PostMessage(cv->HWin, WM_USER_COMMNOTIFY, 0, FD_CLOSE);
                                        cv->RetryWithOtherProtocol = FALSE;
                                        return;
                                }
#else
        if (cv->NoMsg==0)
          MessageBox(cv->HWin,ErrMsg,ErrorCaption,
            MB_TASKMODAL | MB_ICONEXCLAMATION);
        PostMessage(cv->HWin, WM_USER_COMMNOTIFY, 0, FD_CLOSE);
        return;
#endif /* NO_INET6 */
                        }

#ifndef NO_INET6
                        /* here is connection established */
                        cv->RetryWithOtherProtocol = FALSE;
#endif /* NO_INET6 */
                        PWSAAsyncSelect(cv->s,cv->HWin,WM_USER_COMMNOTIFY, FD_READ | FD_OOB | FD_CLOSE);
                        TCPIPClosed = FALSE;
                        break;

                case IdSerial:
                        _snprintf_s(Temp, sizeof(Temp), _TRUNCATE, "%s%d", READENDNAME, cv->ComPort);
                        ReadEnd = CreateEvent(NULL,FALSE,FALSE,Temp);
                        _snprintf_s(Temp, sizeof(Temp), _TRUNCATE, "%s%d", WRITENAME, cv->ComPort);
                        memset(&wol,0,sizeof(OVERLAPPED));
                        wol.hEvent = CreateEvent(NULL,TRUE,TRUE,Temp);
                        _snprintf_s(Temp, sizeof(Temp), _TRUNCATE, "%s%d", READNAME, cv->ComPort);
                        memset(&rol,0,sizeof(OVERLAPPED));
                        rol.hEvent = CreateEvent(NULL,TRUE,FALSE,Temp);

                        /* create the receiver thread */
                        if (_beginthread(CommThread,0,cv) == -1) {
                                get_lang_msg("MSG_TT_ERROR", uimsg, sizeof(uimsg), "Tera Term: Error", ts->UILanguageFile);
                                get_lang_msg("MSG_TT_ERROR", ts->UIMsg, sizeof(ts->UIMsg), "Can't create thread", ts->UILanguageFile);
                                MessageBox(cv->HWin,ts->UIMsg,uimsg,MB_TASKMODAL | MB_ICONEXCLAMATION);
                        }
                        break;

                case IdFile:
                        cv->RRQ = TRUE;
                        break;
        }
        cv->Ready = TRUE;
}

BOOL CommCanClose(PComVar cv)
{ // check if data remains in buffer
        if (! cv->Open) {
                return TRUE;
        }
        if (cv->InBuffCount>0) {
                return FALSE;
        }
        if ((cv->HLogBuf!=NULL) &&
            ((cv->LCount>0) ||
             (cv->DCount>0))) {
                return FALSE;
        }
        if ((cv->HBinBuf!=NULL) &&
            (cv->BCount>0)) {
                return FALSE;
        }
        return TRUE;
}

void CommClose(PComVar cv)
{
        if ( ! cv->Open ) {
                return;
        }
        cv->Open = FALSE;

        /* disable event message posting & flush buffer */
        cv->RRQ = FALSE;
        cv->Ready = FALSE;
        cv->InPtr = 0;
        cv->InBuffCount = 0;
        cv->OutPtr = 0;
        cv->OutBuffCount = 0;
        cv->LineModeBuffCount = 0;
        cv->FlushLen = 0;
        cv->Flush = FALSE;

        /* close port & release resources */
        switch (cv->PortType) {
                case IdTCPIP:
                        if (HAsync!=0) {
                                PWSACancelAsyncRequest(HAsync);
                        }
                        HAsync = 0;
#ifndef NO_INET6
                        freeaddrinfo(cv->res0);
#endif /* NO_INET6 */
                        if ( cv->s!=INVALID_SOCKET ) {
                                Pclosesocket(cv->s);
                        }
                        cv->s = INVALID_SOCKET;
                        TTXCloseTCP(); /* TTPLUG */
                        FreeWinsock();
                        break;
                case IdSerial:
                        if ( cv->ComID != INVALID_HANDLE_VALUE ) {
                                CloseHandle(ReadEnd);
                                CloseHandle(wol.hEvent);
                                CloseHandle(rol.hEvent);
                                PurgeComm(cv->ComID, PURGE_TXABORT | PURGE_RXABORT |
                                                     PURGE_TXCLEAR | PURGE_RXCLEAR);
                                EscapeCommFunction(cv->ComID,CLRDTR);
                                SetCommMask(cv->ComID,0);
                                PCloseFile(cv->ComID);
                                ClearCOMFlag(cv->ComPort);
                        }
                        TTXCloseFile(); /* TTPLUG */
                        break;
                case IdFile:
                        if (cv->ComID != INVALID_HANDLE_VALUE) {
                                PCloseFile(cv->ComID);
                        }
                        TTXCloseFile(); /* TTPLUG */
                        break;
        }
        cv->ComID = INVALID_HANDLE_VALUE;
        cv->PortType = 0;
}

void CommProcRRQ(PComVar cv)
{
        if ( ! cv->Ready ) {
                return;
        }
        /* disable receive request */
        switch (cv->PortType) {
                case IdTCPIP:
                        if (! TCPIPClosed) {
                                PWSAAsyncSelect(cv->s,cv->HWin,WM_USER_COMMNOTIFY, FD_OOB | FD_CLOSE);
                        }
                        break;
                case IdSerial:
                        break;
        }
        cv->RRQ = TRUE;
        CommReceive(cv);
}

void CommReceive(PComVar cv)
{
        DWORD C;
        DWORD DErr;

        if (! cv->Ready || ! cv->RRQ ||
            (cv->InBuffCount>=InBuffSize)) {
                return;
        }

        /* Compact buffer */
        if ((cv->InBuffCount>0) && (cv->InPtr>0)) {
                memmove(cv->InBuff,&(cv->InBuff[cv->InPtr]),cv->InBuffCount);
                cv->InPtr = 0;
        }

        if (cv->InBuffCount<InBuffSize) {
                switch (cv->PortType) {
                        case IdTCPIP:
                                C = Precv(cv->s, &(cv->InBuff[cv->InBuffCount]),
                                          InBuffSize-cv->InBuffCount, 0);
                                if (C == SOCKET_ERROR) {
                                        C = 0;
                                        PWSAGetLastError();
                                }
                                cv->InBuffCount = cv->InBuffCount + C;
                                break;
                        case IdSerial:
                                do {
                                        ClearCommError(cv->ComID,&DErr,NULL);
                                        if (! PReadFile(cv->ComID,&(cv->InBuff[cv->InBuffCount]),
                                                        InBuffSize-cv->InBuffCount,&C,&rol)) {
                                                if (GetLastError() == ERROR_IO_PENDING) {
                                                        if (WaitForSingleObject(rol.hEvent, 1000) != WAIT_OBJECT_0) {
                                                                C = 0;
                                                        }
                                                        else {
                                                                GetOverlappedResult(cv->ComID,&rol,&C,FALSE);
                                                        }
                                                }
                                                else {
                                                        C = 0;
                                                }
                                        }
                                        cv->InBuffCount = cv->InBuffCount + C;
                                } while ((C!=0) && (cv->InBuffCount<InBuffSize));
                                ClearCommError(cv->ComID,&DErr,NULL);
                                break;
                        case IdFile:
                                if (PReadFile(cv->ComID,&(cv->InBuff[cv->InBuffCount]),
                                              InBuffSize-cv->InBuffCount,&C,NULL)) {
                                        if (C == 0) {
                                                DErr = ERROR_HANDLE_EOF;
                                        }
                                        else {
                                                cv->InBuffCount = cv->InBuffCount + C;
                                        }
                                }
                                else {
                                        DErr = GetLastError();
                                }
                                break;
                }
        }

        if (cv->InBuffCount==0) {
                switch (cv->PortType) {
                        case IdTCPIP:
                                if (! TCPIPClosed) {
                                        PWSAAsyncSelect(cv->s,cv->HWin, WM_USER_COMMNOTIFY,
                                                        FD_READ | FD_OOB | FD_CLOSE);
                                }
                                break;
                        case IdSerial:
                                cv->RRQ = FALSE;
                                SetEvent(ReadEnd);
                                return;
                        case IdFile:
                                if (DErr != ERROR_IO_PENDING) {
                                        PostMessage(cv->HWin, WM_USER_COMMNOTIFY, 0, FD_CLOSE);
                                        cv->RRQ = FALSE;
                                }
                                else {
                                        cv->RRQ = TRUE;
                                }
                                return;
                }
                cv->RRQ = FALSE;
        }
}

void CommSend(PComVar cv)
{
        int delay;
        COMSTAT Stat;
        BYTE LineEnd;
        int C, D, Max;
        DWORD DErr;

        if ((! cv->Open) || (! cv->Ready)) {
                cv->OutBuffCount = 0;  
                return;
        }

        if ((cv->OutBuffCount == 0) || (! cv->CanSend)) {
                return;
        }

        /* Max num of bytes to be written */
        switch (cv->PortType) {
                case IdTCPIP:
                        if (TCPIPClosed) {
                                cv->OutBuffCount = 0;
                        }
                        Max = cv->OutBuffCount;
                        break;
                case IdSerial:
                        ClearCommError(cv->ComID,&DErr,&Stat);
                        Max = OutBuffSize - Stat.cbOutQue;
                        break;
                case IdFile:
                        Max = cv->OutBuffCount;
                        break;
        }

        if ( Max<=0 ) {
                return;
        }
        if ( Max > cv->OutBuffCount ) {
                Max = cv->OutBuffCount;
        }

        if (cv->PortType == IdTCPIP && cv->TelFlag) {
                cv->LastSendTime = time(NULL);
        }

        C = Max;
        delay = 0;

        if ( cv->DelayFlag && (cv->PortType==IdSerial) ) {
                if ( cv->DelayPerLine > 0 ) {
                        if ( cv->CRSend==IdCR ) {
                                LineEnd = 0x0d;
                        }
                        else {
                                LineEnd = 0x0a;
                        }
                        C = 1;
                        if ( cv->DelayPerChar==0 ) {
                                while ((C<Max) && (cv->OutBuff[cv->OutPtr+C-1]!=LineEnd)) {
                                        C++;
                                }
                        }
                        if ( cv->OutBuff[cv->OutPtr+C-1]==LineEnd ) {
                                delay = cv->DelayPerLine;
                        }
                        else {
                                delay = cv->DelayPerChar;
                        }
                }
                else if ( cv->DelayPerChar > 0 ) {
                        C = 1;
                        delay = cv->DelayPerChar;
                }
        }

        /* Write to comm driver/Winsock */
        switch (cv->PortType) {
                case IdTCPIP:
                        D = Psend(cv->s, &(cv->OutBuff[cv->OutPtr]), C, 0);
                        if ( D==SOCKET_ERROR ) { /* if error occurs */
                                PWSAGetLastError(); /* Clear error */
                                D = 0;
                        }
                        break;

                case IdSerial:
                        if (! PWriteFile(cv->ComID,&(cv->OutBuff[cv->OutPtr]),C,(LPDWORD)&D,&wol)) {
                                if (GetLastError() == ERROR_IO_PENDING) {
                                        if (WaitForSingleObject(wol.hEvent,1000) != WAIT_OBJECT_0) {
                                                D = C; /* Time out, ignore data */
                                        }
                                        else {
                                                GetOverlappedResult(cv->ComID,&wol,(LPDWORD)&D,FALSE);
                                        }
                                }
                                else { /* I/O error */
                                        D = C; /* ignore error */
                                }
                        }
                        ClearCommError(cv->ComID,&DErr,&Stat);
                        break;

                case IdFile:
                        if (! PWriteFile(cv->ComID, &(cv->OutBuff[cv->OutPtr]), C, (LPDWORD)&D, NULL)) {
                                if (! GetLastError() == ERROR_IO_PENDING) {
                                        D = C; /* ignore data */
                                }
                        }
                        break;
        }

        cv->OutBuffCount = cv->OutBuffCount - D;
        if ( cv->OutBuffCount==0 ) {
                cv->OutPtr = 0;
        }
        else {
                cv->OutPtr = cv->OutPtr + D;
        }

        if ( (C==D) && (delay>0) ) {
                cv->CanSend = FALSE;
                SetTimer(cv->HWin, IdDelayTimer, delay, NULL);
        }
}

void CommSendBreak(PComVar cv)
/* for only serial ports */
{
        MSG DummyMsg;

        if ( ! cv->Ready ) {
                return;
        }

        switch (cv->PortType) {
                case IdSerial:
                        /* Set com port into a break state */
                        SetCommBreak(cv->ComID);

                        /* pause for 1 sec */
                        if (SetTimer(cv->HWin, IdBreakTimer, 1000, NULL) != 0) {
                                GetMessage(&DummyMsg,cv->HWin,WM_TIMER,WM_TIMER);
                        }

                        /* Set com port into the nonbreak state */
                        ClearCommBreak(cv->ComID);
                        break;
        }
}

void CommLock(PTTSet ts, PComVar cv, BOOL Lock)
{
        BYTE b;
        DWORD Func;

        if (! cv->Ready) {
                return;
        }
        if ((cv->PortType==IdTCPIP) ||
            (cv->PortType==IdSerial) &&
            (ts->Flow!=IdFlowHard)) {
                if (Lock) {
                        b = XOFF;
                }
                else {
                        b = XON;
                }
                CommBinaryOut(cv,&b,1);
        }
        else if ((cv->PortType==IdSerial) &&
                 (ts->Flow==IdFlowHard)) {
                if (Lock) {
                        Func = CLRRTS;
                }
                else {
                        Func = SETRTS;
                }
                EscapeCommFunction(cv->ComID,Func);
        }
}

BOOL PrnOpen(PCHAR DevName)
{
        char Temp[MAXPATHLEN];
        DCB dcb;
        DWORD DErr;
        COMMTIMEOUTS ctmo;

        strncpy_s(Temp, sizeof(Temp),DevName, _TRUNCATE);
        Temp[4] = 0; // COMn or LPTn
        LPTFlag = (Temp[0]=='L') ||
                  (Temp[0]=='l');
        PrnID = CreateFile(Temp,GENERIC_WRITE,
                           0,NULL,OPEN_EXISTING,
                           0,NULL);
        if (PrnID == INVALID_HANDLE_VALUE) {
                return FALSE;
        }

        if (GetCommState(PrnID,&dcb)) {
                BuildCommDCB(DevName,&dcb);
                SetCommState(PrnID,&dcb);
        }
        ClearCommError(PrnID,&DErr,NULL);
        if (! LPTFlag) {
                SetupComm(PrnID,0,CommOutQueSize);
        }
        /* flush output buffer */
        PurgeComm(PrnID, PURGE_TXABORT | PURGE_TXCLEAR);
        memset(&ctmo,0,sizeof(ctmo));
        ctmo.WriteTotalTimeoutConstant = 1000;
        SetCommTimeouts(PrnID,&ctmo);
        if (! LPTFlag) {
                EscapeCommFunction(PrnID,SETDTR);
        }
        return TRUE;
}

int PrnWrite(PCHAR b, int c)
{
        int d;
        DWORD DErr;
        COMSTAT Stat;

        if (PrnID == INVALID_HANDLE_VALUE ) {
                return c;
        }

        ClearCommError(PrnID,&DErr,&Stat);
        if (! LPTFlag &&
                (OutBuffSize - (int)Stat.cbOutQue < c)) {
                c = OutBuffSize - Stat.cbOutQue;
        }
        if (c<=0) {
                return 0;
        }
        if (! WriteFile(PrnID,b,c,(LPDWORD)&d,NULL)) {
                d = 0;
        }
        ClearCommError(PrnID,&DErr,NULL);
        return d;
}

void PrnCancel()
{
        PurgeComm(PrnID, PURGE_TXABORT | PURGE_TXCLEAR);
        PrnClose();
}

void PrnClose()
{
        if (PrnID != INVALID_HANDLE_VALUE) {
                if (!LPTFlag) {
                        EscapeCommFunction(PrnID,CLRDTR);
                }
                CloseHandle(PrnID);
        }
        PrnID = INVALID_HANDLE_VALUE;
}