/*% cc -g -DNOCOPYTX -DMANYREGS -DZSTAB -DUNIX -DDIAGS %  -o isz; size isz;
 ****************************************************************************
 *
 * isz.c By Chuck Forsberg,  Omen Technology INC
 *  Copyright 2004 2011 Omen Technology INC All Rights Reserved
 *     This is UNPUBLISHED PROPRIETARY SOURCE CODE of Omen Technology INC.
 *     The Copyright notice above does not evidence any actual or intended
 *     publication such source code.
 *  Entry: see sample main() in code below
 *
 *  External functions called:
 *
 * sendline(c)  sends a character to host
 *
 * purgeline()	empty receive queue
 * int readline(tenths) read char from host, timeout in seconds/10
	return received byte 0 to 0377
	negative return values indicate error:
		return -1 on recoverable error
		return -2 on timeout
	trap fatal errors (loss of carrier, etc.), close file
 * checkline() return non 0 if readline has 1 or more bytes ready
 *
 * zfilbuf() fill buffer with blklen bytes, set Eofseen if EOT, return count
 *	(See #ifdef NOCOPYTX for alternate version)
 * zseek(whence) clear EOF, errors, seek
 * zclose(status) close the input dataset associated with zfilbuf() et al.
 *	N.B: zclose might be called after the file is closed.
 *
 * When trapping on errors, close file, call canit() unless line dropped
 *
 ****************************************************************************
 */

#ifndef IZOK
#include "izm.h"
#endif

#define LOGFILE "/tmp/szlog"
int Verbose=0;
int Fullpath=0;

#ifdef NOCOPYTX
#ifdef KKSIZE
char privsecbuf[KKSIZE];
#else
char privsecbuf[1025];
#endif
#endif

int Zmodem=0;		/* ZMODEM protocol requested by receiver */
unsigned Txwindow=0;	/* Control the size of the transmitted window if non-zero */
unsigned Txwspac;	/* Spacing between zcrcq requests */
unsigned Txwcnt;	/* Counter used to space ack requests */
long vpos = 0;		/* Number of bytes read from file */
long Lrxpos;		/* Receiver's last reported offset */
#ifdef ADDRLE
int Lztrans;
#endif

int wctxpn(), wcs(), getnak(), zsendfile(), getzrxinit(), zsendfdata();
int getinsync(), zfilbuf(), zseek(), zfilbuf(), checkline();
void zclose(int);

//#include "icrctab.c"
//to keep compiler from complaining I inserted icrctab.c instead of "including" it

/*
 *  Crc calculation stuff
 */

/* crctab calculated by Mark G. Mendel, Network Systems Corporation */
static unsigned short icrctab[256] = {
    0x0000,  0x1021,  0x2042,  0x3063,  0x4084,  0x50a5,  0x60c6,  0x70e7,
    0x8108,  0x9129,  0xa14a,  0xb16b,  0xc18c,  0xd1ad,  0xe1ce,  0xf1ef,
    0x1231,  0x0210,  0x3273,  0x2252,  0x52b5,  0x4294,  0x72f7,  0x62d6,
    0x9339,  0x8318,  0xb37b,  0xa35a,  0xd3bd,  0xc39c,  0xf3ff,  0xe3de,
    0x2462,  0x3443,  0x0420,  0x1401,  0x64e6,  0x74c7,  0x44a4,  0x5485,
    0xa56a,  0xb54b,  0x8528,  0x9509,  0xe5ee,  0xf5cf,  0xc5ac,  0xd58d,
    0x3653,  0x2672,  0x1611,  0x0630,  0x76d7,  0x66f6,  0x5695,  0x46b4,
    0xb75b,  0xa77a,  0x9719,  0x8738,  0xf7df,  0xe7fe,  0xd79d,  0xc7bc,
    0x48c4,  0x58e5,  0x6886,  0x78a7,  0x0840,  0x1861,  0x2802,  0x3823,
    0xc9cc,  0xd9ed,  0xe98e,  0xf9af,  0x8948,  0x9969,  0xa90a,  0xb92b,
    0x5af5,  0x4ad4,  0x7ab7,  0x6a96,  0x1a71,  0x0a50,  0x3a33,  0x2a12,
    0xdbfd,  0xcbdc,  0xfbbf,  0xeb9e,  0x9b79,  0x8b58,  0xbb3b,  0xab1a,
    0x6ca6,  0x7c87,  0x4ce4,  0x5cc5,  0x2c22,  0x3c03,  0x0c60,  0x1c41,
    0xedae,  0xfd8f,  0xcdec,  0xddcd,  0xad2a,  0xbd0b,  0x8d68,  0x9d49,
    0x7e97,  0x6eb6,  0x5ed5,  0x4ef4,  0x3e13,  0x2e32,  0x1e51,  0x0e70,
    0xff9f,  0xefbe,  0xdfdd,  0xcffc,  0xbf1b,  0xaf3a,  0x9f59,  0x8f78,
    0x9188,  0x81a9,  0xb1ca,  0xa1eb,  0xd10c,  0xc12d,  0xf14e,  0xe16f,
    0x1080,  0x00a1,  0x30c2,  0x20e3,  0x5004,  0x4025,  0x7046,  0x6067,
    0x83b9,  0x9398,  0xa3fb,  0xb3da,  0xc33d,  0xd31c,  0xe37f,  0xf35e,
    0x02b1,  0x1290,  0x22f3,  0x32d2,  0x4235,  0x5214,  0x6277,  0x7256,
    0xb5ea,  0xa5cb,  0x95a8,  0x8589,  0xf56e,  0xe54f,  0xd52c,  0xc50d,
    0x34e2,  0x24c3,  0x14a0,  0x0481,  0x7466,  0x6447,  0x5424,  0x4405,
    0xa7db,  0xb7fa,  0x8799,  0x97b8,  0xe75f,  0xf77e,  0xc71d,  0xd73c,
    0x26d3,  0x36f2,  0x0691,  0x16b0,  0x6657,  0x7676,  0x4615,  0x5634,
    0xd94c,  0xc96d,  0xf90e,  0xe92f,  0x99c8,  0x89e9,  0xb98a,  0xa9ab,
    0x5844,  0x4865,  0x7806,  0x6827,  0x18c0,  0x08e1,  0x3882,  0x28a3,
    0xcb7d,  0xdb5c,  0xeb3f,  0xfb1e,  0x8bf9,  0x9bd8,  0xabbb,  0xbb9a,
    0x4a75,  0x5a54,  0x6a37,  0x7a16,  0x0af1,  0x1ad0,  0x2ab3,  0x3a92,
    0xfd2e,  0xed0f,  0xdd6c,  0xcd4d,  0xbdaa,  0xad8b,  0x9de8,  0x8dc9,
    0x7c26,  0x6c07,  0x5c64,  0x4c45,  0x3ca2,  0x2c83,  0x1ce0,  0x0cc1,
    0xef1f,  0xff3e,  0xcf5d,  0xdf7c,  0xaf9b,  0xbfba,  0x8fd9,  0x9ff8,
    0x6e17,  0x7e36,  0x4e55,  0x5e74,  0x2e93,  0x3eb2,  0x0ed1,  0x1ef0
};

/*
 * updcrc macro derived from article Copyright (C) 1986 Stephen Satchell. 
 *  NOTE: First srgument must be in range 0 to 255.
 *        Second argument is referenced twice.
 * 
 * Programmers may incorporate any or all code into their programs, 
 * giving proper credit within the source. Publication of the 
 * source routines is permitted so long as proper credit is given 
 * to Stephen Satchell, Satchell Evaluations and Chuck Forsberg, 
 * Omen Technology.
 */

#define updcrc(cp, crc) ( icrctab[((crc >> 8) & 255)] ^ (crc << 8) ^ cp)

/*
 * Copyright (C) 1986 Gary S. Brown.  You may use this program, or
 * code or tables extracted from it, as desired without restriction.
 */

/* First, the polynomial itself and its table of feedback terms.  The  */
/* polynomial is                                                       */
/* X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0 */
/* Note that we take it "backwards" and put the highest-order term in  */
/* the lowest-order bit.  The X^32 term is "implied"; the LSB is the   */
/* X^31 term, etc.  The X^0 term (usually shown as "+1") results in    */
/* the MSB being 1.                                                    */

/* Note that the usual hardware shift register implementation, which   */
/* is what we're using (we're merely optimizing it by doing eight-bit  */
/* chunks at a time) shifts bits into the lowest-order term.  In our   */
/* implementation, that means shifting towards the right.  Why do we   */
/* do it this way?  Because the calculated CRC must be transmitted in  */
/* order from highest-order term to lowest-order term.  UARTs transmit */
/* characters in order from LSB to MSB.  By storing the CRC this way,  */
/* we hand it to the UART in the order low-byte to high-byte; the UART */
/* sends each low-bit to hight-bit; and the result is transmission bit */
/* by bit from highest- to lowest-order term without requiring any bit */
/* shuffling on our part.  Reception works similarly.                  */

/* The feedback terms table consists of 256, 32-bit entries.  Notes:   */
/*                                                                     */
/*     The table can be generated at runtime if desired; code to do so */
/*     is shown later.  It might not be obvious, but the feedback      */
/*     terms simply represent the results of eight shift/xor opera-    */
/*     tions for all combinations of data and CRC register values.     */
/*                                                                     */
/*     The values must be right-shifted by eight bits by the "updcrc"  */
/*     logic; the shift must be unsigned (bring in zeroes).  On some   */
/*     hardware you could probably optimize the shift in assembler by  */
/*     using byte-swap instructions.                                   */

static unsigned long icr3tab[] = { /* CRC polynomial 0xedb88320 */
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

#ifdef NFGM
unsigned long
UPDC32(b, c)
long c;
{
	return (icr3tab[((int)c ^ b) & 0xff] ^ ((c >> 8) & 0x00FFFFFF));
}

#else

#define UPDC32(b, c) (icr3tab[((int)c ^ b) & 0xff] ^ ((c >> 8) & 0x00FFFFFF))
#endif


/* End of icrctab.c */

int Lastrx;
char Lzconv;	/* Local ZMODEM file conversion request */
#ifdef KKSIZE
int blklen=KKSIZE;	/* length of transmitted records */
#else
int blklen=1024;	/* length of transmitted records */
#endif
int Eofseen;		/* EOF seen on input set by zfilbuf */
unsigned Rxbuflen = 16384;	/* Receiver's max buffer length */
unsigned Tframlen = 0;	/* Override for tx frame length */
int Rxflags = 0;
long Lastsync;		/* Last offset to which we got a ZRPOS */
int Beenhereb4;		/* How many times we've been ZRPOS'd same place */
int Zctlesc;	/* Encode control characters */
int Zrwindow = 1400;	/* RX window size (controls garbage count) */
int Rxtimeout = 600;
void saybibi(), startz();

int Exitcode;
int errcnt=0;		/* number of files unreadable */
#ifdef UNIX
#include "rbunix.c"	/* most of the system dependent stuff here */
#endif

#include "izm.c"
#ifdef ADDRLE
#include "izmr.c"
#endif


#ifdef UNIX
FILE *in;

/* called by signal interrupt or terminate to clean things up */
void
bibi(n)
{
	canit(); mode(0);
	fprintf(stderr, "sz: caught signal %d; exiting\n", n);
	if (n == SIGQUIT)
		abort();
	if (n == 99)
		fprintf(stderr, "mode(2) in rbsb.c not implemented!!\n");
	exit(128+n);
}

main(argc, argv)
char *argv[];
{
	register char *cp;
	register npats;
	int dm;
	char **patts;

	if (cp = getenv("VERBOSE"))
		Verbose = atoi(cp);

	npats=0;
	if (argc<2)
		usage();
	while (--argc) {
		cp = *++argv;
		if (*cp++ == '-' && *cp) {
			while ( *cp) {
				switch(*cp++) {
				case 'f':
					++Fullpath; break;
				case 'l':
					if (--argc < 1)
						usage();
					Tframlen = atol(*++argv);
					if (Tframlen<32 || Tframlen>1024)
						usage();
					break;
				case 'r':
					Lzconv = ZCRESUM;
				case 'v':
					++Verbose; break;
				case 'w':
					if (--argc < 1)
						usage();
					Txwindow = atoi(*++argv);
					if (Txwindow < 256)
						Txwindow = 256;
					Txwindow = (Txwindow/64) * 64;
					Txwspac = Txwindow/4;
					if (blklen > Txwspac)
						blklen = Txwspac;
					break;
#ifdef ADDRLE
				case 'Z':
				case 'z':
					Lztrans = ZTRLE;  break;
#endif
				default:
					usage();
				}
			}
		}
		else if ( !npats && argc>0) {
			if (argv[0][0]) {
				npats=argc;
				patts=argv;
			}
		}
	}
	if (npats < 1)
		usage();
	if (Verbose) {
		if (freopen(LOGFILE, "w", stderr)==NULL) {
			printf("Can't open log file %s\n",LOGFILE);
			exit(0200);
		}
		setbuf(stderr, NULL);
	}

	mode(1);

	signal(SIGKILL, bibi);
	signal(SIGINT, SIG_IGN);
	signal(SIGQUIT, SIG_IGN);
	signal(SIGTERM, bibi);

	startz();

	if (wcsend(npats, patts)==IZERROR) {
		Exitcode=0200;
		canit();
	}
	mode(0);
	dm = ((errcnt != 0) | Exitcode);
#ifdef DIAGS
	vfile("isz finished with transfers dm=%x", dm);
#endif
	if (dm) {
		exit(dm);
	}
	exit(0);
	/*NOTREACHED*/
}

wcsend(argc, argp)
char *argp[];
{
	register n;

	bytcnt = -1;
	for (n=0; n<argc; ++n) {
		if (wcs(argp[n])==IZERROR)
			return IZERROR;
	}
	saybibi();
	return IZOK;
}
#endif /* UNIX */


#ifdef SAMPLE
main()
{
	startz();		/* Initialize receiver */

	/*
	 *  To ask receiver for crash rocovery, set
	 *		Lzconv = ZCRESUM;
	 *
	 * call wcs() once for each file.
	 *  Initialize zfilbuf before calling wcs()
	 *  The string is the file name, null terminated
	 *    file length is not sent
	 */
	if (wcs("file.ext"))
		return 1;

	saybibi();		/* Orderly conclusion of ZMODEM session */

	return 0;
	
}
#endif



void
startz()
{
#ifdef BOTH
	Rxtimeout = 600;
#endif
	Zmodem = 0;
#ifdef LDP
	Zldpactive = 0;
	Zcrcpreset = 0xFFFFFFFFL;	/* CRC preset from filename header */
#endif
	mputs("rz\r"); 
	stohdr(0L);
	zshhdr(ZRQINIT, Txhdr);
}

#ifdef UNIX
struct stat filestat;
#endif

int
wcs(name)
char *name;
{
	int ret;

#ifdef UNIX
#ifdef NOCOPYTX
	secbuf = privsecbuf;
#endif
	if ((in=fopen(name, "r"))==NULL) {
		++errcnt;
		return IZOK;	/* pass over it, there may be others */
	}
	fstat(fileno(in), &filestat);
#endif

// COLETTI mod (9/29/15): secbuf needs to be assigned prior to calling wctxpn(), if you want fullpath info to be sent
#ifdef NOCOPYTX
	secbuf = privsecbuf;
#endif

	Eofseen = 0;  vpos = 0;
	
	ret =  wctxpn(name);
#ifdef DIAGS
	vfile("wctxpn returned %d", ret);
#endif
	switch (ret) {
	case ZSKIP:
	case ZFERR:
		return IZOK;
	case IZOK:
		break;
	default:
		return IZERROR;
	}
	return 0;
}

/*
 * generate and transmit pathname block consisting of
 *  pathname (null terminated),
 */
wctxpn(name)
char *name;
{
	register char *p, *q;
	int n;

	if ( !Zmodem)
		if (getnak())
			return IZERROR;
	Zmodem = 1;

	for (p=name, q=secbuf ; *p; ) {
		switch(*q++ = *p++) {
// COLETTI mod (9/29/15): PicoDOS uses back-slahes, not forward-slashes			
		case '\\':
			if (!Fullpath)
				q = secbuf;
		};
	}
	*q++ = 0;
#ifdef UNIX
	sprintf(q, "%lu %lo", filestat.st_size, filestat.st_mtime);
	q += strlen(q);
#else
#ifdef HAVE_STAT
	q += insertStat(q);
#endif
#endif
	*q++ = 0;
	*q++ = 0;
	n = q-secbuf;
	
	return zsendfile(secbuf, n);
}

getnak()
{
	register firstch;

#ifdef DIAGS
	vfile("entering getnak");
#endif
	Lastrx = 0;
	for (;;) {
		switch (firstch = readline(800)) {
		case ZPAD:
			if (getzrxinit())
				return IZERROR;
			return FALSE;
		case TIMEOUT:
			return TRUE;
		case CAN:
			if ((firstch = readline(20)) == CAN && Lastrx == CAN)
				return IZERROR;
		default:
			break;
		}
		Lastrx = firstch;
	}
}


#ifdef UNIX
void
zclose(status)
{
#ifdef DIAGS
	vfile("zclose: status=%d", status);
#endif
	if (in) {
		fclose(in);
#ifdef DIAGS
		vfile("fclose returned");
#endif
	} else {
#ifdef DIAGS
	vfile("file already closed!!");
#endif
	}

	in = 0;
}

int
zseek(n)
long n;
{
	clearerr(in);	/* Clear EOF */
	return (fseek(in, n, 0));
}

/* Fill buffer with blklen chars */
int
zfilbuf()
{
	size_t n;

#ifdef NOCOPYTX
	n = fread(secbuf=privsecbuf, 1, blklen, in);
#else
	n = fread(secbuf, 1, blklen, in);
#endif
	if (n < blklen)
		Eofseen = 1;
	return n;
}


usage()
{
	char **pp;

	fprintf(stderr, "Usage: isz [-l blklen] [-f] [-r] [-v] [-w window] file ...\n");
	exit(0);
}
#endif



/*
 * Get the receiver's init parameters
 */
getzrxinit()
{
	register triesleft;

	for (triesleft=10; --triesleft>=0; ) {
		
		switch (zgethdr()) {
		case ZCHALLENGE:	/* Echo receiver's challenge numbr */
			stohdr(Rxpos);
			zshhdr(ZACK, Txhdr);
			continue;
		case ZRINIT:
#ifdef LDP
			/* LDP protection active */
			Zldpactive = Rxhdr[ZF1] & CANLDP;
#ifdef DIAGS
			vfile("Zldpactive=%d", Zldpactive);
#endif
#endif
			Rxflags = 0377 & Rxhdr[ZF0];
			Txfcs32 = (Rxflags & CANFC32)?1:0;
			Zctlesc |= Rxflags & TESCCTL;
			Rxbuflen = (0377 & Rxhdr[ZP0])+((0377 & Rxhdr[ZP1])<<8);
			if ( !(Rxflags & CANFDX))
				Txwindow = 0;
#ifdef DIAGS
			vfile("Rxbuflen=%d Tframlen=%u", Rxbuflen, Tframlen);
#endif
			/* Override to force shorter frame length */
			if (Rxbuflen && (Rxbuflen>Tframlen) && (Tframlen>=32))
				Rxbuflen = Tframlen;
			if ( !Rxbuflen && (Tframlen>=32) && (Tframlen<=1024))
				Rxbuflen = Tframlen;
#ifdef DIAGS
			vfile("Rxbuflen=%d", Rxbuflen);
#endif

			/* Set initial subpacket length */
			if (Rxbuflen && ((unsigned)blklen)>Rxbuflen)
				blklen = Rxbuflen;
#ifdef DIAGS
			vfile("Rxbuflen=%d blklen=%d", Rxbuflen, blklen);
			vfile("Txwindow = %u Txwspac = %d", Txwindow, Txwspac);
#endif
#ifdef ADDRLE
			if (Lztrans == ZTRLE && (Rxflags & CANRLE))
				Txfcs32 = 2;
			else
				Lztrans = 0;
#endif
#ifdef DIAGS
			vfile("Rxflags=%X Txfcs32=%d", Rxflags, Txfcs32);
#endif

			return IZOK;
		case ZCAN:
		case TIMEOUT:
			return IZERROR;
		default:
			zshhdr(ZNAK, Txhdr);
			continue;
		}
	}
	return IZERROR;
}


/* Send file name and related info */
zsendfile(buf, blen)
char *buf;
{
	register c;
#ifdef LDP
	long crc;
	char *p;
#endif

	for (;;) {
		stohdr(0L);
		Txhdr[ZF0] = Lzconv;	/* file conversion request */
#ifdef LDP
		Zcrcpreset = crc = 0xFFFFFFFFL;
		bytcnt = 0;
		if (Zldpactive)
			Txhdr[ZF3] |= ZSLDP;
#ifdef KKSIZE
		Txhdr[ZF3] |= ZSRWKK;
#endif
#endif
		zsbhdr(ZFILE, Txhdr);
		zsdata(buf, blen, ZCRCW);
#ifdef DIAGS
		vfile("zsendfile: %d %s", blen, buf);
#endif
//	flushmo(); exit(0); // ----------------------
#ifdef LDP
		if (Zldpactive) {
			for (p=buf, c=blen; --c >=0; ++p) {
				crc = UPDC32(*p, crc);
#ifdef DIAGS
				vfile("crc=%lX", crc);
#endif
			}
			for (p = zcpyrldp; *p; ++p)
				crc = UPDC32(*p, crc);
			Zcrcpreset = crc;
#ifdef DIAGS
			vfile("Zcrcpreset=%lX", Zcrcpreset);
#endif
		}
#endif
again:
		c = zgethdr();
		switch (c) {
		case ZRINIT:
#ifdef DIAGS
		vfile("spurious ZRINIT 1");
#endif
			continue;
		case IZERROR:
			continue;
		default:
		case ZCAN:
		case TIMEOUT:
		case ZABORT:
		case ZFIN:
			return IZERROR;
		case ZSKIP:
#ifdef DIAGS
			vfile("1zskip");
#endif
			zclose(IZERROR); return c;
		case ZRPOS:
			/*
			 * Suppress zcrcw request otherwise triggered by
			 * lastyunc==bytcnt
			 */
			if (Rxpos && zseek(Rxpos))
				return IZERROR;
			Lastsync = (bytcnt = Txpos = Rxpos) -1;
			return zsendfdata();
		}
	}
}

#ifdef UNIX
char* pknames[] = {"CRC-16", "CRC-32", "RLE", ""};
#endif
/* Send the data in the file */
zsendfdata()
{
	register c, e, n;
	register newcnt;
	int junkcount;		/* Counts garbage chars received by TX */

	Lrxpos = 0;
	junkcount = 0;
	Beenhereb4 = FALSE;
	goto somemore;

waitack:
	junkcount = 0;
	c = getinsync(0);
gotack:
#ifdef DIAGS
	vfile("gotack: c=%d", c);
#endif
	switch (c) {
	default:
	case ZCAN:
#ifdef DIAGS
		vfile("zcan");
#endif
		zclose(IZERROR);
		return IZERROR;
	case ZSKIP:
#ifdef DIAGS
		vfile("2zskip");
#endif
		zclose(IZERROR);
		return c;
	case ZACK:
	case ZRPOS:
		break;
	case ZRINIT:
#ifdef DIAGS
		vfile("spurious ZRINIT 2");
#endif
		zclose(IZERROR);
		return IZOK;
	}
	while (checkline()) {
		switch (readline(1))
		{
		case XOFF:		/* Wait a while for an XON */
		case XOFF|0200:
			readline(100); continue;
		case CAN:
		case ZPAD:
			c = getinsync(1);
			goto gotack;
		}
	}

somemore:
	newcnt = Rxbuflen;
	Txwcnt = 0;
	e = ZCRCE;


	do {
		if (e == ZCRCE) {
			stohdr(Txpos);
			zsbhdr(ZDATA, Txhdr);
		}
		n = zfilbuf();
		if (Eofseen)
			e = ZCRCE;
		else if (junkcount > 3)
			e = ZCRCW;
		else if (bytcnt == Lastsync)
			e = ZCRCW;
		else if (Rxbuflen && (newcnt -= n) <= 0)
			e = ZCRCW;
		else if (Txwindow) {
#ifdef UNIX
			if (Verbose>1)
				fprintf(stderr, "Txwcnt=%lX\n", Txwcnt);
#endif
			if ((Txwcnt += n) >= Txwspac) {
				Txwcnt = 0;  e = ZCRCQ;
			}
		}
		else
			e = ZCRCG;
#ifdef UNIX
		if (Verbose>1)
			fprintf(stderr, "%7lX ZMODEM %s\n", Txpos, pknames[Crc32t&3]);
#endif
		zsdata(secbuf, n, e);
		bytcnt = Txpos += n;
		if (e == ZCRCW) {
			for (n = 20; --n >=0;)
				sendline(021);
			flushmo();
			goto waitack;
		}
		while (checkline()) {
			switch (readline(1))
			{
			case CAN:
			case ZPAD:
				c = getinsync(1);
				if (c == ZACK)
					break;
#ifdef TCFLSH
				ioctl(wrfd, TCFLSH, 1);
#endif
				/* zcrce - dinna wanna starta ping-pong game */
				zsdata(secbuf, 0, ZCRCE);
				goto gotack;
			case XOFF:		/* Wait a while for an XON */
			case XOFF|0200:
				readline(100);
			case TIMEOUT:
#ifdef UNIX
				vfile("junktest: TIMEOUT");
#endif
				goto nojunk;
			default:
				++junkcount;
			}
		}
nojunk:
		if (Txwindow) {
			while (((unsigned)(Txpos - Lrxpos)) >= Txwindow) {
				if (e != ZCRCQ)
					zsdata(secbuf, 0, e = ZCRCQ);
				c = getinsync(1);
				if (c != ZACK) {
#ifdef TCFLSH
					ioctl(wrfd, TCFLSH, 1);
#endif
					zsdata(secbuf, 0, ZCRCE);
					goto gotack;
				}
			}
		}
	} while (!Eofseen);

	stohdr(Txpos);
	zshhdr(ZEOF, Txhdr);
	for (;;) {
		switch (getinsync(0)) {
		case ZACK:
			continue;
		case ZRPOS:
			goto somemore;
		case ZRINIT:
#ifdef DIAGS
			vfile("ZRINIT on eof");
#endif

#ifdef LDP
#ifdef DIAGS
			vfile("ZGOTFILEOK=%d", Rxhdr[ZF2]);
#endif
			if ((!Zldpactive) || (Rxhdr[ZF2] & ZGOTFILEOK)) {  /* Last file received and closed */
				zclose(IZOK);
				return IZOK;
			} else {
				zclose(IZERROR);
				return IZERROR;
			}
#else
			zclose(IZOK);
			return IZOK;
#endif

		case ZSKIP:
#ifdef DIAGS
			vfile("3zskip");
#endif
			zclose(IZERROR);
			return c;
		default:
#ifdef DIAGS
			vfile("DEFAULT on eof");
#endif
			zclose(IZERROR);
			return IZERROR;
		}
	}
}

/*
 * Respond to receiver's complaint, get back in sync with receiver
 */
getinsync(flag)
{
	register c;

	for (;;) {
		c = zgethdr();
		switch (c) {
		case ZCAN:
		case ZABORT:
		case ZFIN:
		case TIMEOUT:
			return IZERROR;
		case ZRPOS:
#if 1
refoo:			c = readline(1);
			switch (c) {
			case '*':
				continue;
			case 015:  case 012: case 021: case 0221:
				goto refoo;
			default:
				break;
			}
#endif
			/* ************************************* */
			/*  If sending to a buffered modem, you  */
			/*   might send a break at this point to */
			/*   dump the modem's buffer.		 */
			if (zseek(Rxpos))
				return IZERROR;
			Eofseen = 0;
			bytcnt = Lrxpos = Txpos = Rxpos;
			if (Lastsync == Rxpos) {
				if (++Beenhereb4 > 4)
					if (blklen > 64)
						blklen /= 2;
			}
			Lastsync = Rxpos;
			stohdr(Txpos);		// CAF 9-7-2011
			return ZRPOS;
		case ZACK:
			Lrxpos = Rxpos;
			if (flag || Txpos == Rxpos)
				return ZACK;
			continue;
		case ZRINIT:
#ifdef DIAGS
			vfile("zrinit2");
#endif
			return c;
		case ZSKIP:
#ifdef DIAGS
			vfile("4zskip");
#endif
			return c;
		case IZERROR:
		default:
			zshhdr(ZNAK, Txhdr);
			continue;
		}
	}
}


/* Say "bibi" to the receiver, try to do it cleanly */
void
saybibi()
{
	for (;;) {
		stohdr(0L);		/* CAF Was zsbhdr - minor change */
		zshhdr(ZFIN, Txhdr);	/*  to make debugging easier */
		switch (zgethdr()) {
		case ZFIN:
			sendline('O'); sendline('O');
#ifdef FLUSH
			flushmo();
#endif
		/*FALLTHRU*/
		case ZCAN:
		case TIMEOUT:
			return;
		}
	}
}

/* End of isz.c */