xcxmdm.c

支持X/YModem和cis_b+协议的串口通讯程序

	{
	case CAN:
	  show (2, "Receiver CANcelled");
	  return (ERROR);
	case NAK:
	  show (2, "Got a NAK on sector acknowledge ");
	  break;
	case TIMEOUT:
	  show (2, "Timeout on sector acknowledge   ");
	  break;
	case ACK:
	  assert (g_flag == FALSE);
	  firstsec = FALSE;
	  return (OK);
	  break;
	default:
	  sprintf (Msg, "Got %#x for sector acknowledge ", c);
	  show (2, Msg);

	  if (c == crcheck && crcheck)
	    break;		/* imitate NAK */
	  do
	    {
	      if ((c = readbyte (3)) == CAN)
		{
		  show (2, "Receiver CANcelled");
		  return (ERROR);
		}
	    }
	  while (c != TIMEOUT);
	}
      errct++;
      if (!y_flag && (errct == 3) && (badline == FALSE || stx_soh == STX))
	{
	  show (2, "ATTEMPTING RECOVERY ");
	  return (FALLBACK);
	}

    }
  show (2, "Retry count exceeded");
  return (ERROR);
}

/* Transmit a file using XMODEM protocol */
static int
wctx P_((void))
{
    register c ;
    int sectnum, eoflg, attempts;
    int tmpsize, tmpstxh, tmpbdln, terr, ee;

    if (!(xfp = fopen (word, "r")) && !y_done)
      {
	  sprintf (Msg, "Can't open '%s'", word);
	  show(1, Msg); 
	  return (ERROR);
      }
    firstsec = TRUE;
    attempts = 0;
    amdone = FALSE;
    tmpsize = ksecsize;		/* saves sector size for later restoration */
    tmpstxh = stx_soh;		/* saves sector size for later restoration */
    tmpbdln = badline;
    cl_line();
    show(1,"Sync...");

    while ( (c = readbyte(30) ) != NAK && c != WANTCRC && c != WANTCRG && c != CAN)
	if (c == TIMEOUT && ++attempts > RETRYMAX)
	  {
	      show(1,"Receiver not responding");
	      if(!y_done)
	      fclose (xfp);
	      return (ERROR);
	  }
    if (c == CAN)
      {
	  show(1,"Receiver CANcelled");
	  if(!y_done)
	  fclose (xfp);
	  return (ERROR);
      }
    g_flag = FALSE ;	
    if ( c == WANTCRC )
    	crcheck = WANTCRC; 
    else if ( c == WANTCRG )
    	{ crcheck = WANTCRG; g_flag = TRUE ; } 
    else
    	crcheck = FALSE ;
    
    if( crcheck )
	show (1, "CRC packet validation enabled   ");
    else
	show (1, "ATTENTION: CHECKSUM packet validation requested");
    sectnum = y_flag ? 0 : 1;

    do
      {
	  eoflg = getsec ();
	  fprintf (tfp, "Transmitting sector #%d\r", sectnum);

	  if ((terr = wcputsec (sectnum)) == ERROR)
	    {
		if(!y_done)
		fclose (xfp);
		return (ERROR);
	    }
	  else if (terr == FALLBACK)
	    {
		if (stx_soh == STX)
		  {
		      amdone = TRUE;
		  }
		else
		    badline = TRUE;
		sectnum--;
	    }
	  sectnum++;
      }
    while (eoflg);

    ksecsize = tmpsize;
    stx_soh = tmpstxh;
    badline = tmpbdln;
    attempts = 0;
    if (!y_done){ /*  if xmodem,  or if more ymodem packets */ 
    fclose (xfp);
    do{
    sendbyte (EOT);
    ee=readbyte (10) ;
    } while ( ee != ACK && attempts++ < RETRYMAX) ;
    
    if (attempts >= RETRYMAX)
      {
	  show(1,"Receiver not responding to completion");
	  return (ERROR);
      }
    }
    if ( !y_flag || y_done )
    show(1,"Transmission complete           ");
    return (OK);
}

static int
setmode (c)
     int c;
{
    g_flag = FALSE ;
    switch (tolower (c))
      {
      case 'x':
	  textmode = FALSE;	/* the usual case */
      case 't':
	  ksecsize = 128;	/* default for xmodem */
	  stx_soh = SOH;	/* default for xmodem */
	  if (c == 't')
	      textmode = TRUE;
	  break;
      case 'g':
	  g_flag = TRUE ;
      case 'b':
      case 'o':
	  textmode = FALSE;
	  ksecsize = 1024;	/* old ymodem sector size */
	  stx_soh = STX;	/* transmit flag for 1k byte packet size */
	  break;
      case ' ':
	  break;

      default:
	  return FAILURE;
      }

    sprintf (Msg, "%s %s file transfer mode",(y_flag ?"YMODEM":"XMODEM"),(textmode?"Text":"Binary"));
    show(1,Msg);

    return SUCCESS;
}

/* save old signal handler */
static RETSIGTYPE (*oldvec) P_((int));

void
xsend (c)
     int c;
{
    badline = FALSE ;
    oldvec = signal (SIGINT, xmsigint);

    if (setmode (c))
      {
	  g_flag = FALSE ; /* only receiver can set g_flag */
	  sprintf(Msg,"Sending %s",ksecsize == 128 ?"128 byte small packet   "
	          : "1K byte packets XMODEM  ") ; show(1,Msg) ;
	  if (!setjmp (our_env))
	    {
		if (wctx () == ERROR)
		  {
		      sprintf (Msg, "Error transmitting file %s", word);
		      show(1,Msg) ;
		      purge(); 
		      /* return; why isn't signal restored? *??*/
		  }
	    }
      }

    signal (SIGINT, oldvec);
}


/* ymodem -- normalize file name, assume *filn is at least 128 chars */
static char *
getfname( filn, strpflg )
  char *filn; 
  int strpflg ;
{
	char *wtp, *utp ;

	wtp = filn ;
	utp = wtp + 128 ; /* length is 128 */

	while ( *wtp == 0x20 ) { 	/* strip leading spaces */
		wtp++ ;
		if ( wtp == utp )
		    return 0 ; 		/* just spaces, no file name */
	}
	if ( ! filn[0] || ! wtp[0] )
		return 0 ; 		/* empty string */
	if ( *wtp == '.' )
		while( *++wtp == '/' ) 
			; /* increment pointer beyond '/' character */ 

	/* normalize string:  strip away path, etc */ 

	if((utp = strrchr( wtp, '/' )) != NULL) {
		if ( strpflg ) {   
			wtp = utp + 1 ;	/* strip path */
		}
		if ( utp[1] == 0 ) {
			return 0 ;  /* no file name */
		}
	}
	return wtp ;
}


/* parse ymodem header for file name and attributes */

static int
yparse P_((void))
{
	int i = 0 ;
	char *wtp, *utp ;

	phdr.fnam = NULL ;
	phdr.fsiz = 0 ;
	phdr.fdat = 0 ;
	phdr.fprm = 0 ;

	while ( i < 128 && wcbuf[i] ) i++ ;	/*!! fix the 128 thingy!*/
	if ( i == 0 || i >= ksecsize ) {
		y_done = TRUE ;
		return OK ;
	}
	/* need some error checking here: */
        utp = getfname( wcbuf, TRUE );	
	strcpy ( Name, utp );	
	phdr.fnam = Name ;
	if ( (xfp = QueryCreate (Resume_Not_Allowed)) == NULL) {
		return (ERROR);			/* can't open file */
	}
	while ( *utp != 0 ) utp++ ; utp++ ;	/* point to start of len*/ 
	phdr.fsiz = strtol( utp, &wtp, 10 ); 	/* get file length 	*/
	if ( *wtp == 0x20 ) { 			/* file date is included */
		phdr.fdat = strtol( wtp, &utp, 8 );
		if ( *utp == 0x20 ){
			phdr.fprm = strtoul( utp, &wtp, 8 ) & 07777 ;
			*wtp = 0 ; /* terminate string */
		} 
	}
	cl_line();
	sprintf(Msg,"%s %ld %s",phdr.fnam, phdr.fsiz,(phdr.fprm ? utp : " ")); 
	fprintf(stderr,"\r%s\n\r",Msg);
	return OK ;

}


/* Receive a file using XMODEM protocol */
static int
wcrx P_((void))
{
    register sectnum, sectcurr;

    if ( !y_flag ){
    	/* open file for xmodem reception */
    	strcpy (Name, word);
    	xfp = QueryCreate (Resume_Not_Allowed) ;
    	if ( xfp == NULL)
		return (ERROR); 
    }

    firstsec = TRUE;
    sectnum = y_flag ? -1 : 0 ;
    sendchar = g_flag? WANTCRG : WANTCRC ;
    sync = FALSE;
    y_done = FALSE;
    crcheck = TRUE;
    show(2,"Sync...");

    while (TRUE)
      {
	  if (badline)
	      purge ();
	  if ( g_flag == FALSE && sync ) /* g-mode doesn't ACK */
	      sendbyte (sendchar);
	  if ( y_done )
	      { cl_line(); return OK; }
	  /* 
	     Here we are at this if() on the second pass through the loop.
	     Here we start the ymodem transmission body after we have grabbed
	     the intial header with file name. Presumably crcheck
	     equals 'G' or 'C' or 0 at this juncture in time . . . 
	  */
	  if ( sectnum == 0 && y_flag ) {
		assert(!crcheck || crcheck == WANTCRG || crcheck == WANTCRC);
	        sendbyte((crcheck ? crcheck : NAK));
	  }

	  sectcurr = wcgetsec (Maxtime);

	  if (sectcurr == ((sectnum + 1) & 0xff))
	    {
		if ( firstsec ){
			if ( y_flag ){	/* open file for rx */
				if (yparse() == ERROR ) return ERROR;
			}
			else{ 
				fprintf(stderr,"\r%s\n\r", Name );
			}
			firstsec = FALSE ;
		}
		sectnum++;
	        if (sectnum == 1)
	            show (1,(ksecsize == 128 ? "Sender using 128 byte packets   ":"Sender using 1K byte packets    "));
		if ( sectnum > 0 )
		    putsec ();
		fprintf (tfp, "Received sector #%d\r", sectnum);
		sendchar = ACK;
		continue;
	    }

	  if (sectcurr == (sectnum & 0xff))
	    {
		sprintf (Msg, "Received duplicate sector #%d", sectnum);
		show(2,Msg);
		sendchar = ACK;
		continue;
	    }

	  fclose(xfp);
	  if( y_flag ) set_dp( phdr.fnam, phdr.fdat, phdr.fprm );

	  if (sectcurr == WCEOT)
	    {
		show( 1,"File received OK                ");
		sendbyte (ACK);
		return (OK);
	    }

	  if (sectcurr == ERROR)
	      return (ERROR);

	  sprintf (Msg, "Sync error ... expected %d(%d), got %d",
		   (sectnum + 1) & 0xff, sectnum, sectcurr);
	  show(1,Msg);
	  return (ERROR);
      }
}


/*      Put received WC sector into a UNIX file
        using text translations if neccesary.
*/

void
xreceive (c)
     int c;
{
    badline = FALSE ;
    oldvec = signal (SIGINT, xmsigint);

    if (setmode (c))
      {
	  if (!setjmp (our_env))
	    {
		if (wcrx () == ERROR)
		    canit ();
		/* return; why isn't signal restored first? *??*/
	    }
      }

    signal (SIGINT, oldvec);
}

static int
build_hdr P_((void))
{
	int retcode = 0, i = 0;
	struct stat sbuf ;
	char *fname, *tpr = wcbuf ;

        while ( i < SECSIZ ) tpr[i] = 0, i++ ;  /* clear buffer */
	getword();
	fname = getfname( word, TRUE );

	if ( fname )
	{
		if ( stat( word, &sbuf ))
		{
			perror( fname );
			fprintf(stderr, "\rCan't stat()  %s\n\r", fname );
			retcode = -1 ;
		}
		else
		{
			smallhdr = TRUE ;
			strcpy( wcbuf, fname );
			while( *tpr ) tpr++ ; tpr++ ; 
			sprintf(tpr,"%ld %lo %o", sbuf.st_size, sbuf.st_mtime, sbuf.st_mode);
			fprintf(stderr,"%s %ld %-25o\n\r", fname, sbuf.st_size, sbuf.st_mode);
			while( *tpr ) tpr++ ;
			if ( 128 < (tpr - wcbuf) ) smallhdr = FALSE ;
		}	
	}
	else 
	{
		y_done = smallhdr = TRUE ;
	}
	return retcode ;
}



void
ysend P_((void))
{
    y_done = FALSE ;
    badline = FALSE ;
    oldvec = signal (SIGINT, xmsigint);

    if (setmode ('b'))
      {
	
	  g_flag = FALSE ; /* only receiver can set g_flag */
	  sprintf (Msg, "Sending %s", ksecsize == 128 ? "128 byte small packet YMODEM"
	          : "1K byte packets YMODEM  ") ; show(1,Msg) ;
	  if (!setjmp (our_env))
	    {
		while( !y_done )
		{
			if( !build_hdr() ) 
			{
				if (wctx () == ERROR)
		  		{
		      		sprintf (Msg, "Error transmitting file %s", word);
		      		show(1,Msg) ;
		      		purge(); 
				y_done = TRUE ;
		      		/* return; why isn't signal restored? *??*/
		  		}
			}
		}
	    }
	    purge(); 
      }
    signal (SIGINT, oldvec);
    g_flag = smallhdr = FALSE ;
}


void
yreceive( e )
 int e ;
{
    y_done = FALSE ;
    badline = FALSE ;
    oldvec = signal (SIGINT, xmsigint);
    
    purge();
    if (setmode ('b'))
    {
	  if (!setjmp (our_env))
	    {
    		g_flag = (e == 'g' ? TRUE : FALSE ); 
		while( y_done == FALSE )
		{
			if (wcrx () == ERROR)
			{
			cl_line();
			sprintf (Msg, "Error receiving file %s", word);
			show(1,Msg) ;
			purge(); 
			y_done = TRUE ;
			/* return; why isn't signal restored? *??*/
			}
		}
	    }
      }
    signal (SIGINT, oldvec);
    g_flag = smallhdr = FALSE ;
}