sz.c

ZMODEM协议的实现

	if (in==NULL) {
		++errcnt;
		return OK;	/* pass over it, there may be others */
	}
	BEofseen = Eofseen = 0;  vpos = 0;

#ifdef STAT
	/* Check for directory or block special files */
	fstat(fileno(in), &f);
	c = f.st_mode & S_IFMT;
	if (c == S_IFDIR || c == S_IFBLK) {
		fclose(in);
		return OK;
	}
#endif

	++Filcnt;
	switch (wctxpn(name)) {
	case ERROR:
		return ERROR;
	case ZSKIP:
		return OK;
	}
#ifdef STAT
	if (!Zmodem && wctx(f.st_size)==ERROR)
		return ERROR;
#else
	if (!Zmodem && wctx(1000000000L)==ERROR)
		return ERROR;
#endif

#ifndef vax11c
#ifndef GENIE
	if (Unlinkafter)
		unlink(oname);
#endif
#endif

	return 0;
}

/*
 * generate and transmit pathname block consisting of
 *  pathname (null terminated),
 *  file length, mode time and file mode in octal
 *  as provided by the Unix fstat call.
 *  N.B.: modifies the passed name, may extend it!
 */
wctxpn(name)
char *name;
{
	register char *p, *q;
	char name2[PATHLEN];
#ifdef STAT
	struct stat f;
#endif

	if (Modem2) {
#ifdef STAT
		if (*name && fstat(fileno(in), &f)!= -1) {
			fprintf(stderr, "Sending %s, %ld XMODEM blocks. ",
			  name, (127+f.st_size)>>7);
		}
#endif
		fprintf(stderr, "Give your local XMODEM receive command now.\r\n");
		fflush(stderr);
		return OK;
	}
	zperr("Awaiting pathname nak for %s", *name?name:"<END>");
	if ( !Zmodem)
		if (getnak())
			return ERROR;

	q = (char *) 0;
	if (Dottoslash) {		/* change . to . */
		for (p=name; *p; ++p) {
			if (*p == '/')
				q = p;
			else if (*p == '.')
				*(q=p) = '/';
		}
		if (q && strlen(++q) > 8) {	/* If name>8 chars */
			q += 8;			/*   make it .ext */
			strcpy(name2, q);	/* save excess of name */
			*q = '.';
			strcpy(++q, name2);	/* add it back */
		}
	}

	for (p=name, q=txbuf ; *p; )
		if ((*q++ = *p++) == '/' && !Fullname)
			q = txbuf;
	*q++ = 0;
	p=q;
	while (q < (txbuf + 1024))
		*q++ = 0;
	if (*name) {
#ifdef XX
		if (Thisflen >= 0) {
			sprintf(p, "%u 0 0 0 %d %ld",
			  Thisflen, Filesleft, Totalleft);
			Totalleft -= Thisflen;
		}
#endif
#ifdef GENIE
		else
			sprintf(p, "%d", fdes.current_file_size * 1260);
		vfile("%s open Binfile=%d size=%ld", name, Binfile,
		  fdes.current_file_size * 1260);
#endif

#ifdef STAT
#ifndef XX
		if (fstat(fileno(in), &f)!= -1)
			sprintf(p, "%lu %lo %o 0 %d %ld", f.st_size, f.st_mtime,
			  f.st_mode, Filesleft, Totalleft);
		Totalleft -= f.st_size;
#endif
#endif

	}
	if (--Filesleft <= 0)
		Totalleft = 0;
	if (Totalleft < 0)
		Totalleft = 0;

#ifdef STAT
	/* force 1k blocks if name won't fit in 128 byte block */
	if (txbuf[125])
		blklen=1024;
	else {		/* A little goodie for IMP/KMD */
		txbuf[127] = (f.st_size + 127) >>7;
		txbuf[126] = (f.st_size + 127) >>15;
	}
#endif
	if (Zmodem)
		return zsendfile(txbuf, 1+strlen(p)+(p-txbuf));
	if (wcputsec(txbuf, 0, 128)==ERROR)
		return ERROR;
	return OK;
}

getnak()
{
	register firstch;

	Lastrx = 0;
	for (;;) {
		switch (firstch = readline(800)) {
		case ZPAD:
			if (getzrxinit())
				return ERROR;
			Ascii = 0;	/* Receiver does the conversion */
			return FALSE;
		case TIMEOUT:
			zperr("Timeout on pathname");
			return TRUE;
		case WANTG:
#ifdef MODE2OK
			mode(2);	/* Set cbreak, XON/XOFF, etc. */
#endif
			Optiong = TRUE;
			blklen=1024;
		case WANTCRC:
			Crcflg = TRUE;
		case NAK:
			return FALSE;
		case CAN:
			if ((firstch = readline(20)) == CAN && Lastrx == CAN)
				return TRUE;
		default:
			break;
		}
		Lastrx = firstch;
	}
}


wctx(flen)
long flen;
{
	register int thisblklen;
	register int sectnum, attempts, firstch;
	long charssent;

	charssent = 0;  firstsec=TRUE;  thisblklen = blklen;
	vfile("wctx:file length=%ld", flen);

	while ((firstch=readline(Rxtimeout))!=NAK && firstch != WANTCRC
	  && firstch != WANTG && firstch!=TIMEOUT && firstch!=CAN)
		;
	if (firstch==CAN) {
		zperr("Receiver CANcelled");
		return ERROR;
	}
	if (firstch==WANTCRC)
		Crcflg=TRUE;
	if (firstch==WANTG)
		Crcflg=TRUE;
	sectnum=0;
	for (;;) {
		if (flen <= (charssent + 896L))
			thisblklen = 128;
		if ( !filbuf(txbuf, thisblklen))
			break;
		if (wcputsec(txbuf, ++sectnum, thisblklen)==ERROR)
			return ERROR;
		charssent += thisblklen;
	}
	fclose(in);
	attempts=0;
	do {
		purgeline();
		sendline(EOT);
		flushmo();
		++attempts;
	}
		while ((firstch=(readline(Rxtimeout)) != ACK) && attempts < RETRYMAX);
	if (attempts == RETRYMAX) {
		zperr("No ACK on EOT");
		return ERROR;
	}
	else
		return OK;
}

wcputsec(buf, sectnum, cseclen)
char *buf;
int sectnum;
int cseclen;	/* data length of this sector to send */
{
	register checksum, wcj;
	register char *cp;
	unsigned oldcrc;
	int firstch;
	int attempts;

	firstch=0;	/* part of logic to detect CAN CAN */

	if (Verbose>2)
		fprintf(stderr, "Sector %3d %2dk\n", Totsecs, Totsecs/8 );
	else if (Verbose>1)
		fprintf(stderr, "\rSector %3d %2dk ", Totsecs, Totsecs/8 );
	for (attempts=0; attempts <= RETRYMAX; attempts++) {
		Lastrx= firstch;
		sendline(cseclen==1024?STX:SOH);
		sendline(sectnum);
		sendline(-sectnum -1);
		oldcrc=checksum=0;
		for (wcj=cseclen,cp=buf; --wcj>=0; ) {
			sendline(*cp);
			oldcrc=updcrc((0377& *cp), oldcrc);
			checksum += *cp++;
		}
		if (Crcflg) {
			oldcrc=updcrc(0,updcrc(0,oldcrc));
			sendline((int)oldcrc>>8);
			sendline((int)oldcrc);
		}
		else
			sendline(checksum);
		flushmo();

		if (Optiong) {
			firstsec = FALSE; return OK;
		}
		firstch = readline(Rxtimeout);
gotnak:
		switch (firstch) {
		case CAN:
			if(Lastrx == CAN) {
cancan:
				zperr("Cancelled");  return ERROR;
			}
			break;
		case TIMEOUT:
			zperr("Timeout on sector ACK"); continue;
		case WANTCRC:
			if (firstsec)
				Crcflg = TRUE;
		case NAK:
			zperr("NAK on sector"); continue;
		case ACK: 
			firstsec=FALSE;
			Totsecs += (cseclen>>7);
			return OK;
		case ERROR:
			zperr("Got burst for sector ACK"); break;
		default:
			zperr("Got %02x for sector ACK", firstch); break;
		}
		for (;;) {
			Lastrx = firstch;
			if ((firstch = readline(Rxtimeout)) == TIMEOUT)
				break;
			if (firstch == NAK || firstch == WANTCRC)
				goto gotnak;
			if (firstch == CAN && Lastrx == CAN)
				goto cancan;
		}
	}
	zperr("Retry Count Exceeded");
	return ERROR;
}

/* fill buf with count chars padding with ^Z for CPM */
filbuf(buf, count)
register char *buf;
{
	register c, m;

	if ( !Ascii) {
		m = read(fileno(in), buf, count);
		if (m <= 0)
			return 0;
		while (m < count)
			buf[m++] = 032;
		return count;
	}
	m=count;
	if (Lfseen) {
		*buf++ = 012; --m; Lfseen = 0;
	}
	while ((c=getc(in))!=EOF) {
		if (c == 012) {
			*buf++ = 015;
			if (--m == 0) {
				Lfseen = TRUE; break;
			}
		}
		*buf++ =c;
		if (--m == 0)
			break;
	}
	if (m==count)
		return 0;
	else
		while (--m>=0)
			*buf++ = CPMEOF;
	return count;
}

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

#ifdef TXBSIZE
	vfile("zfilbuf: bytcnt =%lu vpos=%lu blklen=%d", bytcnt, vpos, blklen);
	/* We assume request is within buffer, or just beyond */
	txbuf = Txb + (bytcnt & TXBMASK);
	if (vpos <= bytcnt) {
#ifdef GENIE
		if (Binfile) {
			long l, m;  char *p;

			for (p=txbuf, n=0, l=blklen;  l;  l -= 128, p+= 128) {
				n += m = fgetb(p, 128, in);
				if (m == 0)
					break;
			}
		} else
#endif
		n = fread(txbuf, 1, blklen, in);

		vpos += n;
		if (n < blklen)
			Eofseen = 1;
		vfile("zfilbuf: n=%d vpos=%lu Eofseen=%d", n, vpos, Eofseen);
		return n;
	}
	if (vpos >= (bytcnt+blklen))
		return blklen;
	/* May be a short block if crash recovery etc. */
	Eofseen = BEofseen;
	return (vpos - bytcnt);
#else
	n = fread(txbuf, 1, blklen, in);
	if (n < blklen)
		Eofseen = 1;
	return n;
#endif
}

#ifdef TXBSIZE
/* Replacement for brain damaged fseek function.  Returns 0==success */
fooseek(fptr, pos, whence)
FILE *fptr;
long pos;
{
	long m, n;
#ifdef GENIE
	long l, k;  char *p;
#endif

	vfile("fooseek: pos =%lu vpos=%lu Canseek=%d", pos, vpos, Canseek);
	/* Seek offset < current buffer */
	if (pos < (vpos -TXBSIZE +1024)) {
		BEofseen = 0;
		if (Canseek > 0) {
			vpos = pos & ~TXBMASK;
			if (vpos >= pos)
				vpos -= TXBSIZE;
			if (fseek(fptr, vpos, 0))
				return 1;
		}
		else if (Canseek == 0) {
#ifdef GENIE
			if (Binfile) {
				if (fseekb(fptr, vpos = 0L, 0))
					return 1;
				} else
#endif
			if (fseek(fptr, vpos = 0L, 0))
				return 1;
		} else
			return 1;
		while (vpos < pos) {
#ifdef GENIE
			if (Binfile) {
				for (p=Txb,n=0,l=TXBSIZE; l; l -= 128,p+= 128) {
					n += (k = fgetb(p, 128, fptr));
					vfile("bsk1: l=%d k=%d", l, k);
					if (k == 0)
						break;
				}
			} else
#endif
			n = fread(Txb, 1, TXBSIZE, fptr);
			vpos += n;
			vfile("n=%d vpos=%ld", n, vpos);
			if (n < TXBSIZE) {
				BEofseen = 1;
				break;
			}
		}
		vfile("vpos=%ld", vpos);
		return 0;
	}
	/* Seek offset > current buffer (Crash Recovery, etc.) */
	if (pos > vpos) {
		if (Canseek)
			if (fseek(fptr, vpos = (pos & ~TXBMASK), 0))
				return 1;
		while (vpos <= pos) {
			txbuf = Txb + (vpos & TXBMASK);
			m = TXBSIZE - (vpos & TXBMASK);
			vfile("m=%ld vpos=%ld", m,vpos);
#ifdef GENIE
			if (Binfile) {
				for (p=txbuf,n=0,l=m; l; l -= 128,p+= 128) {
					n += (k = fgetb(p, 128, fptr));
					vfile("bsk2: l=%d k=%d n=%d", l, k, n);
					if (k == 0)
						break;
				}
			} else
#endif
				n = fread(txbuf, 1, m, fptr);
			vfile("n=%ld vpos=%ld", n,vpos);
			vpos += n;
			vfile("bo=%d m=%ld vpos=%ld", txbuf-Txb,m,vpos);
			if (n < m) {
				BEofseen = 1;
				break;
			}
		}
		return 0;
	}
	/* Seek offset is within current buffer */
	vfile("within buffer: vpos=%ld", vpos);
	return 0;
}
#define fseek fooseek
#endif


/* VARARGS1 */
vfile(f, a, b, c, d)
register char *f;
{
	if (Verbose > 2) {
		fprintf(stderr, f, a, b, c, d);
		fprintf(stderr, "\n");
	}
}


alrm()
{
	longjmp(tohere, -1);
}


#ifndef GENIE
#ifndef vax11c
/*
 * readline(timeout) reads character(s) from file descriptor 0
 * timeout is in tenths of seconds
 */
readline(timeout)
{
	register int c;
	static char byt[1];

	fflush(stdout);
	if (setjmp(tohere)) {
		zperr("TIMEOUT");
		return TIMEOUT;
	}
	c = timeout/10;
	if (c<2)
		c=2;
	if (Verbose>5) {
		fprintf(stderr, "Timeout=%d Calling alarm(%d) ", timeout, c);
	}
	signal(SIGALRM, alrm); alarm(c);
	c=read(0, byt, 1);
	alarm(0);
	if (Verbose>5)
		fprintf(stderr, "ret %x\n", byt[0]);
	if (c<1)
		return TIMEOUT;
	return (byt[0]&0377);
}

flushmo()
{
	fflush(stdout);
}


purgeline()
{
#ifdef USG
	ioctl(0, TCFLSH, 0);
#else
	lseek(0, 0L, 2);
#endif
}
#endif
#endif

/* send cancel string to get the other end to shut up */
canit()
{
	static char canistr[] = {
	 24,24,24,24,24,24,24,24,24,24,8,8,8,8,8,8,8,8,8,8,0
	};

#ifdef vax11c
	raw_wbuf(strlen(canistr), canistr);
	purgeline();
#else
	printf(canistr);
	fflush(stdout);
#endif
}


/*
 * Log an error
 */
/*VARARGS1*/
zperr(s,p,u)
char *s, *p, *u;
{
	if (Verbose <= 0)
		return;
	fprintf(stderr, "Retry %d: ", errors);
	fprintf(stderr, s, p, u);
	fprintf(stderr, "\n");
}

/*
 * substr(string, token) searches for token in string s
 * returns pointer to token within string if found, NULL otherwise
 */
char *
substr(s, t)
register char *s,*t;
{
	register char *ss,*tt;
	/* search for first char of token */
	for (ss=s; *s; s++)
		if (*s == *t)
			/* compare token with substring */
			for (ss=s,tt=t; ;) {
				if (*tt == 0)
					return s;
				if (*ss++ != *tt++)
					break;
			}
	return NULL;
}

char *babble[] = {
#ifdef vax11c
	"Send file(s) with ZMODEM/YMODEM/XMODEM Protocol",
	"	(Y) = Option applies to YMODEM only",
	"	(Z) = Option applies to ZMODEM only",
	"Usage:	sz [-2+abdefkLlNnquvwYy] [-] file ...",
	"	sz [-2Ceqv] -c COMMAND",
	"	\\ Force next option letter to upper case",
	"	sb [-2adfkquv] [-] file ...",
	"	sx [-2akquv] [-] file",
#endif
#ifndef vax11c
	"Send file(s) with ZMODEM/YMODEM/XMODEM Protocol",
	"	(Y) = Option applies to YMODEM only",
	"	(Z) = Option applies to ZMODEM only",
	"Usage:	sz [-2+abdefkLlNnquvwYy] [-] file ...",
	"	sz [-2Ceqv] -c COMMAND",
	"	sb [-2adfkquv] [-] file ...",
	"	sx [-2akquv] [-] file",
#endif
#ifdef CSTOPB
	"	2   Use 2 stop bits",
#endif
	"	+   Append to existing destination file (Z)",
	"	a   (ASCII) change NL to CR/LF",
	"	b   Binary file transfer override",
	"	c   send COMMAND (Z)",
#ifndef vax11c
	"	d   Change '.' to '/' in pathnames (Y/Z)",
#endif
	"	e   Escape all control characters (Z)",
	"	f   send Full pathname (Y/Z)",
	"	i   send COMMAND, ack Immediately (Z)",
	"	k   Send 1024 byte packets (Y)",
	"	L N Limit subpacket length to N bytes (Z)",
	"	l N Limit frame length to N bytes (l>=L) (Z)",
	"	n   send file only if source newer (Z)",
	"	N   send file only if source newer or longer (Z)",
	"	o   Use 16 bit CRC instead of 32 bit CRC (Z)",
	"	p   Protect existing destination file (Z)",
	"	r   Resume/Recover interrupted file transfer (Z)",
	"	q   Quiet (no progress reports)",
#ifndef vax11c
	"	u   Unlink (remove) file after transmission",
#endif
	"	v   Verbose - provide debugging information",
	"	w N restrict Window to N bytes (Z)",
	"	Y   Yes, overwrite existing file, skip if not present at rx (Z)",
	"	y   Yes, overwrite existing file (Z)",
	"	Z   Activate ZMODEM compression(Z)",
	""
};

usage()
{
	char **pp;

	for (pp=babble; **pp; ++pp)
		fprintf(stderr, "%s\n", *pp);
	fprintf(stderr, "%s for %s by Chuck Forsberg, Omen Technology INC\n",
	 VERSION, OS);
	fprintf(stderr, "\t\t\042The High Reliability Software\042\n");
	cucheck();
	exit(SS_NORMAL);
}

/*
 * Get the receiver's init parameters
 */
getzrxinit()
{
	register n;
#ifdef STAT
	struct stat f;
#endif

	for (n=10; --n>=0; ) {
		
		switch (zgethdr(Rxhdr, 1)) {
		case ZCHALLENGE:	/* Echo receiver's challenge numbr */
			stohdr(Rxpos);
			zshhdr(4, ZACK, Txhdr);
			continue;
		case ZCOMMAND:		/* They didn't see out ZRQINIT */
			stohdr(0L);
			zshhdr(4, ZRQINIT, Txhdr);
			continue;
		case ZRINIT:
			Rxflags = 0377 & Rxhdr[ZF0];
			Usevhdrs = Rxhdr[ZF1] & CANVHDR;
			Txfcs32 = (Wantfcs32 && (Rxflags & CANFC32));
			Zctlesc |= Rxflags & TESCCTL;
			Rxbuflen = (0377 & Rxhdr[ZP0])+((0377 & Rxhdr[ZP1])<<8);
			if ( !(Rxflags & CANFDX))
				Txwindow = 0;
			vfile("Rxbuflen=%d Tframlen=%d", Rxbuflen, Tframlen);
			if ( !Fromcu)
				signal(SIGINT, SIG_IGN);
#ifdef MODE2OK
			mode(2);	/* Set cbreak, XON/XOFF, etc. */