/**  receive a file  **/
rfile(name)
char *name;
{
	char mode;
	int fd, j, firstchar, sectnum, sectcurr, tmode;
	int sectcomp, errors, errorflag, recfin;
	register int bufctr, checksum;
	register int c;
	int errorchar, fatalerror, startstx, inchecksum, endetx, endenq;
	long recvsectcnt;

	mode = XMITTYPE;  /* set t/b mode */
	if ((fd = creat(name, CREATMODE)) < 0)
	  	error("Can't create file for receive", FALSE);
	setmodes();  /* setup tty modes for xfer */
	printf("\r\nUMODEM:  File Name: %s", name);
	if (LOGFLAG)
	{    fprintf(LOGFP, "\n----\nUMODEM Receive Function\n");
	     fprintf(LOGFP, "File Name: %s\n", name);
	     if (FTP1)
		if (!BIT7)
	         fprintf(LOGFP, "TERM II File Transfer Protocol 1 Selected\n");
		else
		 fprintf(LOGFP, "TERM II File Transfer Protocol 4 Selected\n");
	     else
		fprintf(LOGFP,
		  "TERM II File Transfer Protocol 3 (CP/M UG) Selected\n");
	     if (BIT7)
		fprintf(LOGFP, "7-Bit Transmission Enabled\n");
	     else
		fprintf(LOGFP, "8-Bit Transmission Enabled\n");
	}
	printf("\r\nUMODEM:  ");
	if (BIT7)
		printf("7-Bit");
	else
		printf("8-Bit");
	printf(" Transmission Enabled");
	printf("\r\nUMODEM:  Ready to RECEIVE File\r\n");

	recfin = FALSE;
	sectnum = errors = 0;
	fatalerror = FALSE;  /* NO fatal errors */
	recvsectcnt = 0;  /* number of received sectors */

	if (mode == 't')
		tmode = TRUE;
	else
		tmode = FALSE;

	if (FTP1)
	{
	  while (readbyte(4) != SYN);
	  sendbyte(ACK);  /* FTP 1 Sync */
	}
	else sendbyte(NAK);  /* FTP 3 Sync */

        do
        {   errorflag = FALSE;
            do {
                  firstchar = readbyte(6);
            } while ((firstchar != SOH) && (firstchar != EOT) && (firstchar 
		     != TIMEOUT));
            if (firstchar == TIMEOUT)
	    {  if (LOGFLAG)
		fprintf(LOGFP, "Timeout on Sector %d\n", sectnum);
               errorflag = TRUE;
	    }

            if (firstchar == SOH)
	    {  if (FTP1) readbyte(5);  /* discard leading zero */
               sectcurr = readbyte(delay);
               sectcomp = readbyte(delay);
	       if (FTP1) startstx = readbyte(delay);  /* get leading STX */
               if ((sectcurr + sectcomp) == BITMASK)
               {  if (sectcurr == ((sectnum+1)&BITMASK))
		  {  checksum = 0;
		     for (j = bufctr = 0; j < BBUFSIZ; j++)
	      	     {  buff[bufctr] = c = readbyte(delay);
		        checksum = ((checksum+c)&BITMASK);
			if (!tmode)  /* binary mode */
			{  bufctr++;
		           continue;
		        }
			if (c == CR)
			   continue;  /* skip CR's */
			if (c == CTRLZ)  /* skip CP/M EOF char */
			{  recfin = TRUE;  /* flag EOF */
		           continue;
		        }
		        if (!recfin)
			   bufctr++;
		     }
		     if (FTP1) endetx = readbyte(delay);  /* get ending ETX */
		     inchecksum = readbyte(delay);  /* get checksum */
		     if (FTP1) endenq = readbyte(delay); /* get ENQ */
		     if (checksum == inchecksum)  /* good checksum */
		     {  errors = 0;
			recvsectcnt++;
		        sectnum = sectcurr;  /* update sector counter */
			if (write(fd, buff, bufctr) < 0)
			   error("File Write Error", TRUE);
		        else
			{  if (FTP1) sendbyte(ESC);  /* FTP 1 requires <ESC> */
			   sendbyte(ACK);
			}
		     }
		     else
		     {  if (LOGFLAG)
				fprintf(LOGFP, "Checksum Error on Sector %d\n",
				sectnum);
		        errorflag = TRUE;
		     }
                  }
                  else
                  { if (sectcurr == sectnum)
                    {  while(readbyte(3) != TIMEOUT);
		       if (FTP1) sendbyte(ESC);  /* FTP 1 requires <ESC> */
            	       sendbyte(ACK);
                    }
                    else
		    {  if (LOGFLAG)
			{ fprintf(LOGFP, "Phase Error - Received Sector is ");
			  fprintf(LOGFP, "%d while Expected Sector is %d\n",
			   sectcurr, ((sectnum+1)&BITMASK));
			}
			errorflag = TRUE;
			fatalerror = TRUE;
			if (FTP1) sendbyte(ESC);  /* FTP 1 requires <ESC> */
			sendbyte(CAN);
		    }
	          }
           }
           else
	   {  if (LOGFLAG)
		fprintf(LOGFP, "Header Sector Number Error on Sector %d\n",
		   sectnum);
               errorflag = TRUE;
	   }
        }
	if (FTP1 && !errorflag)
	{  if (startstx != STX)
	   {  errorflag = TRUE;  /* FTP 1 STX missing */
	      errorchar = STX;
	   }
	   if (endetx != ETX)
	   {  errorflag = TRUE;  /* FTP 1 ETX missing */
	      errorchar = ETX;
	   }
	   if (endenq != ENQ)
	   {  errorflag = TRUE;  /* FTP 1 ENQ missing */
	      errorchar = ENQ;
	   }
	   if (errorflag && LOGFLAG)
	   {  fprintf(LOGFP, "Invalid Packet-Control Character:  ");
	      switch (errorchar) {
		case STX : fprintf(LOGFP, "STX"); break;
		case ETX : fprintf(LOGFP, "ETX"); break;
		case ENQ : fprintf(LOGFP, "ENQ"); break;
		default  : fprintf(LOGFP, "Error"); break;
	      }
	      fprintf(LOGFP, "\n");
	   }
	}
        if (errorflag == TRUE)
        {  errors++;
	   while (readbyte(3) != TIMEOUT);
           sendbyte(NAK);
        }
  }
  while ((firstchar != EOT) && (errors != ERRORMAX) && !fatalerror);
  if ((firstchar == EOT) && (errors < ERRORMAX))
  {  if (!FTP1) sendbyte(ACK);
     close(fd);
     restoremodes(FALSE);  /* restore normal tty modes */
     if (FTP1)
	while (readbyte(3) != TIMEOUT);  /* flush EOT's */
     sleep(3);  /* give other side time to return to terminal mode */
     if (LOGFLAG)
     {  fprintf(LOGFP, "\nReceive Complete\n");
	fprintf(LOGFP,"Number of Received CP/M Records is %ld\n", recvsectcnt);
     }
     printf("\n");
  }
  else
  {  if (LOGFLAG && FTP1 && fatalerror) fprintf(LOGFP,
	"Synchronization Error");
     error("TIMEOUT -- Too Many Errors", TRUE);
  }
}

/**  send a file  **/
sfile(name)
char *name;
{
	char mode;
	int fd, attempts;
	int nlflag, sendfin, tmode;
	register int bufctr, checksum, sectnum;
	char c;
	int sendresp;  /* response char to sent block */

	nbchr = 0;  /* clear buffered read char count */
	mode = XMITTYPE;  /* set t/b mode */
	if ((fd = open(name, 0)) < 0)
	{  if (LOGFLAG) fprintf(LOGFP, "Can't Open File\n");
     	   error("Can't open file for send", FALSE);
	}
	setmodes();  /* setup tty modes for xfer */	
	printf("\r\nUMODEM:  File Name: %s", name);
	if (LOGFLAG)
	{   fprintf(LOGFP, "\n----\nUMODEM Send Function\n");
	    fprintf(LOGFP, "File Name: %s\n", name);
	}
	printf("\r\n"); prfilestat(name);  /* print file size statistics */
	if (LOGFLAG)
	{  if (FTP1)
	      if (!BIT7)
		fprintf(LOGFP, "TERM II File Transfer Protocol 1 Selected\n");
	      else
		fprintf(LOGFP, "TERM II File Transfer Protocol 4 Selected\n");
	   else
		fprintf(LOGFP,
		   "TERM II File Transfer Protocol 3 (CP/M UG) Selected\n");
	   if (BIT7)
		fprintf(LOGFP, "7-Bit Transmission Enabled\n");
	   else
		fprintf(LOGFP, "8-Bit Transmission Enabled\n");
	}
	printf("\r\nUMODEM:  ");
	if (BIT7)
		printf("7-Bit");
	else
		printf("8-Bit");
	printf(" Transmission Enabled");
	printf("\r\nUMODEM:  Ready to SEND File\r\n");

	if (mode == 't')
	   tmode = TRUE;
	else
	   tmode = FALSE;

        sendfin = nlflag = FALSE;
  	attempts = 0;

	if (FTP1)
	{  sendbyte(SYN);  /* FTP 1 Synchronize with Receiver */
	   while (readbyte(5) != ACK)
	   {  if(++attempts > RETRYMAX*6) error("Remote System Not Responding",
		TRUE);
	      sendbyte(SYN);
	   }
	}
	else
	{  while (readbyte(30) != NAK)  /* FTP 3 Synchronize with Receiver */
	   if (++attempts > RETRYMAX) error("Remote System Not Responding",
		TRUE);
	}

	sectnum = 1;  /* first sector number */
	attempts = 0;

        do 
	{   for (bufctr=0; bufctr < BBUFSIZ;)
	    {   if (nlflag)
	        {  buff[bufctr++] = LF;  /* leftover newline */
	           nlflag = FALSE;
	        }
		if (getbyte(fd, &c) == EOF)
		{  sendfin = TRUE;  /* this is the last sector */
		   if (!bufctr)  /* if EOF on sector boundary */
		      break;  /* avoid sending extra sector */
		   if (tmode)
		      buff[bufctr++] = CTRLZ;  /* Control-Z for CP/M EOF */
	           else
		      bufctr++;
		   continue;
	        }
		if (tmode && c == LF)  /* text mode & Unix newline? */
	    	{  if (c == LF)  /* Unix newline? */
		   {  buff[bufctr++] = CR;  /* insert carriage return */
		      if (bufctr < BBUFSIZ)
	                 buff[bufctr++] = LF;  /* insert Unix newline */
	 	      else
		         nlflag = TRUE;  /* insert newline on next sector */
		   }
		   continue;
	   	}	
		buff[bufctr++] = c;  /* copy the char without change */
	    }
            attempts = 0;
	
	    if (!bufctr)  /* if EOF on sector boundary */
   	       break;  /* avoid sending empty sector */

            do
            {   sendbyte(SOH);  /* send start of packet header */
		if (FTP1) sendbyte(0);  /* FTP 1 Type 0 Packet */
                sendbyte(sectnum);  /* send current sector number */
                sendbyte(-sectnum-1);  /* and its complement */
		if (FTP1) sendbyte(STX);  /* send STX */
                checksum = 0;  /* init checksum */
                for (bufctr=0; bufctr < BBUFSIZ; bufctr++)
                {  sendbyte(buff[bufctr]);  /* send the byte */
		   if (ARPA && (buff[bufctr]==0xff))  /* ARPA Net FFH esc */
			sendbyte(buff[bufctr]);  /* send 2 FFH's for one */
                   checksum = ((checksum+buff[bufctr])&BITMASK);
	        }
/*		while (readbyte(3) != TIMEOUT);   flush chars from line */
		if (FTP1) sendbyte(ETX);  /* send ETX */
                sendbyte(checksum);  /* send the checksum */
		if (FTP1) sendbyte(ENQ);  /* send ENQ */
                attempts++;
		if (FTP1)
		{  sendresp = NAK;  /* prepare for NAK */
		   if (readbyte(10) == ESC) sendresp = readbyte(10);
		}
		else
		   sendresp = readbyte(10);  /* get response */
		if ((sendresp != ACK) && LOGFLAG)
		   { fprintf(LOGFP, "Non-ACK Received on Sector %d\n",
		      sectnum);
		     if (sendresp == TIMEOUT)
			fprintf(LOGFP, "This Non-ACK was a TIMEOUT\n");
		   }
            }   while((sendresp != ACK) && (attempts != RETRYMAX));
            sectnum++;  /* increment to next sector number */
    }  while (!sendfin && (attempts != RETRYMAX));

    if (attempts == RETRYMAX)
	error("Remote System Not Responding", TRUE);

    attempts = 0;
    if (FTP1)
	while (attempts++ < 10) sendbyte(EOT);
    else
    {	sendbyte(EOT);  /* send 1st EOT */
	while ((readbyte(15) != ACK) && (attempts++ < RETRYMAX))
	   sendbyte(EOT);
	if (attempts >= RETRYMAX)
	   error("Remote System Not Responding on Completion", TRUE);
    }

    close(fd);
    restoremodes(FALSE);  
    sleep(5);  /* give other side time to return to terminal mode */
    if (LOGFLAG)
    {  fprintf(LOGFP, "\nSend Complete\n");
    }
    printf("\n");

}

/*  print file size status information  */
prfilestat(name)
char *name;
{
	struct stat filestatbuf; /* file status info */

	stat(name, &filestatbuf);  /* get file status bytes */
	printf("  Estimated File Size %ldK, %ld Records, %ld Bytes",
	  (filestatbuf.st_size/1024)+1, (filestatbuf.st_size/128)+1,
	  filestatbuf.st_size);
	if (LOGFLAG)
	  fprintf(LOGFP,"Estimated File Size %ldK, %ld Records, %ld Bytes\n",
	  (filestatbuf.st_size/1024)+1, (filestatbuf.st_size/128)+1,
	  filestatbuf.st_size);
	return;
}

/* get a byte from data stream -- timeout if "seconds" elapses */
readbyte(seconds)
unsigned seconds;
{
	char c;
	
	signal(SIGALRM,alarmfunc);  /* catch alarms */	
	alarm(seconds);  /* set the alarm clock */
	if (read(0, &c, 1) < 0)  /* get a char; error means we timed out */
	  {
	     return(TIMEOUT);
	  }
	alarm(0);  /* turn off the alarm */
	return((c&BITMASK));  /* return the char */
}

/* send a byte to data stream */
sendbyte(data)
char data;
{
	char dataout;
	dataout = (data&BITMASK);  /* mask for 7 or 8 bits */
	write(1, &dataout, 1);  /* write the byte */
	return;
}

/* function for alarm clock timeouts */
alarmfunc()
{
	return;  /* this is basically a dummy function to force error */
		 /* status return on the "read" call in "readbyte"    */
}

/* print data on TTY setting */
ttyparams()
{
	
/*  Obtain TTY parameters for JHU UNIX  */
#ifdef JHU	
	gtty(0, &ttystemp);  /* get current tty params */
#endif

/*  Obtain TTY parameters for Version 7 UNIX  */
#ifdef VER7
	ioctl(0,TIOCGETP,&ttystemp);
#endif

/*  Obtain TTY parameters for UNIX SYSTEM III  */
#ifdef SYS3
	gtty(0, &ttystemp);  /* get current tty params */
#endif

	tty = ttyname(0);  /* get name of tty */
	stat(tty, &statbuf);  /* get more tty params */

	printf("\r\n\nTTY Device Parameter Display");
	  printf("\r\n\tTTY Device Name is %s\r\n\n", tty);
	  printf("\tAny Parity Allowed "); pryn(ANYP);
	  printf("\tEven Parity Allowed"); pryn(EVENP);
	  printf("\tOdd Parity Allowed "); pryn(ODDP);
	  printf("\tEcho Enabled       "); pryn(ECHO);
	  printf("\tLower Case Map     "); pryn(LCASE);
	  printf("\tTabs Expanded      "); pryn(XTABS);
	  printf("\tCR Mode Enabled    "); pryn(CRMOD);
	  printf("\tRAW Mode Enabled   "); pryn(RAW);

/*  Print extended terminal characteristics for JHU UNIX  */
#ifdef JHU
	  printf("\tBinary Mode Enabled"); pryn1(NB8);
	  printf("\tCR/LF in Col 72    "); pryn1(FOLD);
	  printf("\tRecognize ^S/^Q    "); pryn1(STALL);
	  printf("\tSend ^S/^Q         "); pryn1(TAPE);
	  printf("\tTerminal can BS    "); pryn1(SCOPE);
	  printf("\r\n");  /* New line to separate topics */
	  printf("\tTerminal Paging is "); pryn1(PAGE);
	    if (ttystemp.xflags&PAGE)
		printf("\t  Lines/Page is %d\r\n", ttystemp.xflags&PAGE);
	  printf("\r\n");  /* New line to separate topics */
	  printf("\tTTY Input Rate     :   ");
	    prbaud(ttystemp.ispeed);  /* print baud rate */
	  printf("\tTTY Output Rate    :   ");
	    prbaud(ttystemp.ospeed);  /* print output baud rate */
	  printf("\r\n");  /* New line to separate topics */
	  printf("\tMessages Enabled   ");
		if (statbuf.st_mode&011)
		   printf(":   Yes\r\n");
		else
		   printf(":   No\r\n");
#endif

/*  Print extended characteristics for Version 7 UNIX  */
#ifdef VER7
	  printf("\tTTY Input Rate     :   ");
	    prbaud(ttystemp.sg_ispeed);
	  printf("\tTTY Output Rate    :   ");
	    prbaud(ttystemp.sg_ospeed);  /* print output baud rate */
#endif

/*  Print extended characteristics for UNIX SYSTEM III  */
#ifdef SYS3
	  printf("\tTTY Input Rate     :   ");
	    prbaud(ttystemp.sg_ispeed);
	  printf("\tTTY Output Rate    :   ");
	    prbaud(ttystemp.sg_ospeed);  /* print output baud rate */
#endif

}

pryn(iflag)
int iflag;
{

/*  JHU UNIX flag test  */
#ifdef JHU
	if (ttystemp.mode&iflag)
#endif

/*  Version 7 UNIX flag test  */
#ifdef VER7
	if (ttystemp.sg_flags&iflag)
#endif

/*  UNIX SYSTEM III flag test  */
#ifdef SYS3
	if (ttystemp.sg_flags&iflag)
#endif

	   printf(":   Yes\r\n");
	else
	   printf(":   No\r\n");
}

/*  Extended flag test for JHU UNIX only  */
#ifdef JHU
pryn1(iflag)
int iflag;
{
	if (ttystemp.xflags&iflag)
	   printf(":   Yes\r\n");
	else
	   printf(":   No\r\n");
}
#endif

prbaud(speed)
char speed;
{
	switch (speed) {

/*  JHU UNIX speed flag cases  */
#ifdef JHU		
		case B0050 : printf("50"); break;
		case B0075 : printf("75"); break;
		case B0110 : printf("110"); break;
		case B0134 : printf("134.5"); break;
		case B0150 : printf("150"); break;
		case B0200 : printf("200"); break;
		case B0300 : printf("300"); break;
		case B0600 : printf("600"); break;
		case B1200 : printf("1200"); break;
		case B1800 : printf("1800"); break;
		case B2400 : printf("2400"); break;
		case B4800 : printf("4800"); break;
		case B9600 : printf("9600"); break;
		case EXT_A : printf("External A"); break;
		case EXT_B : printf("External B"); break;
#endif

/*  Version 7 UNIX speed flag cases  */
#ifdef VER7
		case B50 : printf("50"); break;
		case B75 : printf("75"); break;
		case B110 : printf("110"); break;
		case B134 : printf("134.5"); break;
		case B150 : printf("150"); break;
		case B200 : printf("200"); break;
		case B300 : printf("300"); break;
		case B600 : printf("600"); break;
		case B1200 : printf("1200"); break;
		case B1800 : printf("1800"); break;
		case B2400 : printf("2400"); break;
		case B4800 : printf("4800"); break;
		case B9600 : printf("9600"); break;
		case EXTA : printf("External A"); break;
		case EXTB : printf("External B"); break;
#endif

/*  UNIX SYSTEM III speed flag cases  */
#ifdef SYS3
		case B50 : printf("50"); break;
		case B75 : printf("75"); break;
		case B110 : printf("110"); break;
		case B134 : printf("134.5"); break;
		case B150 : printf("150"); break;
		case B200 : printf("200"); break;
		case B300 : printf("300"); break;
		case B600 : printf("600"); break;
		case B1200 : printf("1200"); break;
		case B1800 : printf("1800"); break;
		case B2400 : printf("2400"); break;
		case B4800 : printf("4800"); break;
		case B9600 : printf("9600"); break;
		case EXTA : printf("External A"); break;
		case EXTB : printf("External B"); break;
#endif

		default    : printf("Error"); break;
	}
	printf(" Baud\r\n");
}