lrz.c

Debian Linux下的通讯程序

 * Wcgetsec fetches a Ward Christensen type sector.
 * Returns sector number encountered or ERROR if valid sector not received,
 * or CAN CAN received
 * or WCEOT if eot sector
 * time is timeout for first char, set to 4 seconds thereafter
 ***************** NO ACK IS SENT IF SECTOR IS RECEIVED OK **************
 *    (Caller must do that when he is good and ready to get next sector)
 */

wcgetsec(rxbuf, maxtime)
char *rxbuf;
int maxtime;
{
	register checksum, wcj, firstch;
	register unsigned short oldcrc;
	register char *p;
	int sectcurr;

	for (Lastrx=errors=0; errors<RETRYMAX; errors++) {

		if ((firstch=readline(maxtime))==STX) {
			Blklen=1024; goto get2;
		}
		if (firstch==SOH) {
			Blklen=128;
get2:
			sectcurr=readline(1);
			if ((sectcurr+(oldcrc=readline(1)))==0377) {
				oldcrc=checksum=0;
				for (p=rxbuf,wcj=Blklen; --wcj>=0; ) {
					if ((firstch=readline(1)) < 0)
						goto bilge;
					oldcrc=updcrc(firstch, oldcrc);
					checksum += (*p++ = firstch);
				}
				if ((firstch=readline(1)) < 0)
					goto bilge;
				if (Crcflg) {
					oldcrc=updcrc(firstch, oldcrc);
					if ((firstch=readline(1)) < 0)
						goto bilge;
					oldcrc=updcrc(firstch, oldcrc);
					if (oldcrc & 0xFFFF)
						zperr( "CRC");
					else {
						Firstsec=FALSE;
						return sectcurr;
					}
				}
				else if (((checksum-firstch)&0377)==0) {
					Firstsec=FALSE;
					return sectcurr;
				}
				else
					zperr( "Checksum");
			}
			else
				zperr("Sector number garbled");
		}
		/* make sure eot really is eot and not just mixmash */
#ifdef NFGVMIN
		else if (firstch==EOT && readline(1)==TIMEOUT)
			return WCEOT;
#else
		else if (firstch==EOT && Lleft==0)
			return WCEOT;
#endif
		else if (firstch==CAN) {
			if (Lastrx==CAN) {
				zperr( "Sender CANcelled");
				return ERROR;
			} else {
				Lastrx=CAN;
				continue;
			}
		}
		else if (firstch==TIMEOUT) {
			if (Firstsec)
				goto humbug;
bilge:
			zperr( "TIMEOUT");
		}
		else
			zperr( "Got 0%o sector header", firstch);

humbug:
		Lastrx=0;
		while(readline(1)!=TIMEOUT)
			;
		if (Firstsec) {
			sendline(Crcflg?WANTCRC:NAK);
			Lleft=0;	/* Do read next time ... */
		} else {
			maxtime=40; sendline(NAK);
			Lleft=0;	/* Do read next time ... */
		}
	}
	/* try to stop the bubble machine. */
	canit();
	return ERROR;
}

/*
 * This version of readline is reasoably well suited for
 * reading many characters.
 *  (except, currently, for the Regulus version!)
 *
 * timeout is in tenths of seconds
 */
readline(timeout)
int timeout;
{
	register n;
#ifndef READLINE_PF
	static char *readline_ptr;	/* pointer for removing chars from linbuf */
#endif

	if (--Lleft >= 0) {
		if (Verbose > 8) {
			fprintf(stderr, "%02x ", *readline_ptr&0377);
		}
		return (*readline_ptr++ & 0377);
	}

	if (!no_timeout)
	{
		n = timeout/10;
		if (n < 2)
			n = 3;
		if (Verbose > 5)
			fprintf(stderr, "Calling read: alarm=%d  Readnum=%d ",
			  n, Readnum);
		signal(SIGALRM, alrm); alarm(n);
	}
	else if (Verbose > 5)
		fprintf(stderr, "Calling read: Readnum=%d ",
		  Readnum);

	Lleft=read(iofd, readline_ptr=linbuf, Readnum);
	if (!no_timeout)
		alarm(0);
	if (Verbose > 5) {
		fprintf(stderr, "Read returned %d bytes\n", Lleft);
	}
	if (Lleft < 1)
		return TIMEOUT;
	--Lleft;
	if (Verbose > 8) {
		fprintf(stderr, "%02x ", *readline_ptr&0377);
	}
	return (*readline_ptr++ & 0377);
}



/*
 * Purge the modem input queue of all characters
 */
purgeline()
{
	Lleft = 0;
#ifdef TCFLSH
	ioctl(iofd, TCFLSH, 0);
#else
	lseek(iofd, 0L, 2);
#endif
}

/*
 * Process incoming file information header
 */
procheader(name)
char *name;
{
	register char *openmode, *p, **pp;
	int tabs, tab_num;

	/* set default parameters and overrides */
	openmode = "w";
	Thisbinary = (!Rxascii) || Rxbinary;
	if (Lzmanag)
		zmanag = Lzmanag;

	/*
	 *  Process ZMODEM remote file management requests
	 */
	if (!Rxbinary && zconv == ZCNL)	/* Remote ASCII override */
		Thisbinary = 0;
	if (zconv == ZCBIN)	/* Remote Binary override */
		Thisbinary = TRUE;
	else if (zmanag == ZMAPND)
		openmode = "a";
	if (Thisbinary && zconv == ZCBIN && try_resume)
		zconv=ZCRESUM;

#ifdef ENABLE_TIMESYNC
	in_timesync=0;
	if (timesync_flag && 0==strcmp(name,"$time$.t"))
		in_timesync=1;
#endif
	/* Check for existing file */
	if (zconv != ZCRESUM && !Rxclob && (zmanag&ZMMASK) != ZMCLOB && (fout=fopen(name, "r"))) {
#ifdef ENABLE_TIMESYNC
	    if (!in_timesync)
#endif
		fclose(fout);  return ERROR;
	}

	Bytesleft = DEFBYTL; Filemode = 0; Modtime = 0L;

	p = name + 1 + strlen(name);
	if (*p) {	/* file coming from Unix or DOS system */
		sscanf(p, "%ld%lo%o", &Bytesleft, &Modtime, &Filemode);
		if (Filemode & UNIXFILE)
			++Thisbinary;
	} else {		/* File coming from CP/M system */
		for (p=name; *p; ++p)		/* change / to _ */
			if ( *p == '/')
				*p = '_';

		if ( *--p == '.')		/* zap trailing period */
			*p = 0;
	}

#ifdef ENABLE_TIMESYNC
	if (in_timesync)
	{
		long t=time(0);
		long d=t-Modtime;
		if (d<0)
			d=0;
		if ((Verbose && d>60) || Verbose > 1)
			fprintf(stderr,  
	"TIMESYNC: here %ld, remote %ld, diff %d seconds\n",
			(long) t, (long) Modtime, (long) d);
#ifdef HAVE_SETTIMEOFDAY
		if (timesync_flag > 1 && d > 10)
		{
			struct timeval tv;
			tv.tv_sec=Modtime;
			tv.tv_usec=0;
			if (settimeofday(&tv,NULL))
				fprintf(stderr, "TIMESYNC: cannot set time: %s\n",
				strerror(errno));
		}
#endif
		return ERROR; /* skips file */
	}
#endif /* ENABLE_TIMESYNC */

	if (!Zmodem && MakeLCPathname && !IsAnyLower(name)
	  && !(Filemode&UNIXFILE))
		uncaps(name);
	if (Topipe > 0) {
		sprintf(Pathname, "%s %s", Progname+2, name);
		if (Verbose)
			fprintf(stderr,  "Topipe: %s %s\n",
			  Pathname, Thisbinary?"BIN":"ASCII");
		if ((fout=popen(Pathname, "w")) == NULL)
			return ERROR;
	} else {
		strcpy(Pathname, name);
		if (Verbose)
			fprintf(stderr, "\nReceiving: %s\n", name);
		timing(1);
		checkpath(name);
		if (Nflag)
			name = "/dev/null";
#ifdef OMEN
		if (name[0] == '!' || name[0] == '|') {
			if ( !(fout = popen(name+1, "w"))) {
				return ERROR;
			}
			Topipe = -1;  return(OK);
		}
#endif
		if (Thisbinary && zconv==ZCRESUM) {
			struct stat st;
			fout = fopen(name, "r+");
			if (fout && 0==fstat(fileno(fout),&st))
			{
				/* retransfer whole blocks */
				rxbytes = st.st_size & ~(1024);
				/* Bytesleft == filelength on remote */
				if (rxbytes < Bytesleft) {
					if (fseek(fout, rxbytes, 0)) {
						fclose(fout);
						return ZFERR;
					}
				}
				goto buffer_it;
			}
			rxbytes=0;
			if (fout)
				fclose(fout);
		}
#ifdef ENABLE_MKDIR
		fout = fopen(name, openmode);
		if ( !fout && Restricted < 2)
			if (make_dirs(name))
				fout = fopen(name, openmode);
#else
		fout = fopen(name, openmode);
#endif
		if ( !fout)
		{
			int e=errno;
			fprintf(stderr, "lrz: cannot open %s: %s\n", name,
				strerror(e));
			return ERROR;
		}
	}
buffer_it:
	if (Topipe == 0) {
		static char *s=NULL;
		if (!s) {
			s=malloc(16384);
			if (!s) {
				fprintf(stderr,"lrz: out of memory\r\n");
				exit(1);
			}
#ifdef SETVBUF_REVERSED
			setvbuf(fout,_IOFBF,s,16384);
#else
			setvbuf(fout,s,_IOFBF,16384);
#endif
		}
	}

	return OK;
}

#ifdef ENABLE_MKDIR
/*
 *  Directory-creating routines from Public Domain TAR by John Gilmore
 */

/*
 * After a file/link/symlink/dir creation has failed, see if
 * it's because some required directory was not present, and if
 * so, create all required dirs.
 */
make_dirs(pathname)
register char *pathname;
{
	register char *p;		/* Points into path */
	int madeone = 0;		/* Did we do anything yet? */
	int save_errno = errno;		/* Remember caller's errno */
	char *strchr();

	if (errno != ENOENT)
		return 0;		/* Not our problem */

	for (p = strchr(pathname, '/'); p != NULL; p = strchr(p+1, '/')) {
		/* Avoid mkdir of empty string, if leading or double '/' */
		if (p == pathname || p[-1] == '/')
			continue;
		/* Avoid mkdir where last part of path is '.' */
		if (p[-1] == '.' && (p == pathname+1 || p[-2] == '/'))
			continue;
		*p = 0;				/* Truncate the path there */
		if ( !mkdir(pathname, 0777)) {	/* Try to create it as a dir */
			vfile("Made directory %s\n", pathname);
			madeone++;		/* Remember if we made one */
			*p = '/';
			continue;
		}
		*p = '/';
		if (errno == EEXIST)		/* Directory already exists */
			continue;
		/*
		 * Some other error in the mkdir.  We return to the caller.
		 */
		break;
	}
	errno = save_errno;		/* Restore caller's errno */
	return madeone;			/* Tell them to retry if we made one */
}

#endif /* ENABLE_MKDIR */

/*
 * Putsec writes the n characters of buf to receive file fout.
 *  If not in binary mode, carriage returns, and all characters
 *  starting with CPMEOF are discarded.
 */
putsec(buf, n)
     char *buf;
     register n;
{
	register char *p;

	if (n == 0)
		return OK;
	if (Thisbinary) {
		if (fwrite(buf,n,1,fout)!=1)
			return ERROR;
	}
	else {
		if (Eofseen)
			return OK;
		for (p=buf; --n>=0; ++p ) {
			if ( *p == '\r')
				continue;
			if (*p == CPMEOF) {
				Eofseen=TRUE; return OK;
			}
			putc(*p ,fout);
		}
	}
	return OK;
}

/*
 *  Send a character to modem.  Small is beautiful.
 */
sendline(c)
{
	char d;

	d = c;
	if (Verbose>6)
		fprintf(stderr, "Sendline: %x\n", c);
	write(1, &d, 1);
}

flushmo() {}

/* make string s lower case */
uncaps(s)
register char *s;
{
	for ( ; *s; ++s)
		if (isupper(*s))
			*s = tolower(*s);
}
/*
 * IsAnyLower returns TRUE if string s has lower case letters.
 */
IsAnyLower(s)
register char *s;
{
	for ( ; *s; ++s)
		if (islower(*s))
			return TRUE;
	return FALSE;
}

/*
 * 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");
}

/* 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
	};

	printf(canistr);
	Lleft=0;	/* Do read next time ... */
	fflush(stdout);
}


report(sct)
int sct;
{
	if (Verbose>1)
		fprintf(stderr,"Blocks received: %d\r",sct);
}

/*
 * If called as [-][dir/../]vrzCOMMAND set Verbose to 1
 * If called as [-][dir/../]rzCOMMAND set the pipe flag
 * If called as rb use YMODEM protocol
 */
chkinvok(s)
char *s;
{
	register char *p;

	p = s;
	while (*p == '-')
		s = ++p;
	while (*p)
		if (*p++ == '/')
			s = p;
	if (*s == 'v') {
		Verbose=1; ++s;
	}
	Progname = s;
	if (*s == 'l') {
		/* lrz -> rz */
		++s;
	}
	if (s[0]=='r' && s[1]=='z')
		Batch = TRUE;
	if (s[0]=='r' && s[1]=='b')
		Batch = Nozmodem = TRUE;
	if (s[2] && s[0]=='r' && s[1]=='b')
		Topipe = 1;
	if (s[2] && s[0]=='r' && s[1]=='z')
		Topipe = 1;
}