/*% 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 *     This is UNPUBLISHED PROPRIETARY SOURCE CODE of Omen Technology INC.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"

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
	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++) {
		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 */