ckutio.c

C语言核心协议的C语言源代码,用于早期网络通信

/* Got the line, now set the desired value for local. */

    if (*lcl < 0) *lcl = xlocal;

/* Some special stuff for v7... */

#ifdef	V7
	if (kmem[TTY] < 0) {	/*  If open, then skip this.  */
		qaddr[TTY] = initrawq(ttyfd);	/* Init the queue. */
		if ((kmem[TTY] = open("/dev/kmem", 0)) < 0) {
			fprintf(stderr, "Can't read /dev/kmem in ttopen.\n");
			perror("/dev/kmem");
			exit(1);
		}
	}
#endif	V7

/* Request exclusive access on systems that allow it. */

#ifndef XENIX
/* Xenix exclusive access prevents open(close(...)) from working... */
#ifdef TIOCEXCL
    	if (ioctl(ttyfd,TIOCEXCL, NULL) < 0)
	    fprintf(stderr,"Warning, problem getting exclusive access\n");
#endif
#endif

/* Get tty device settings */

#ifndef UXIII
    gtty(ttyfd,&ttold);			/* Get sgtty info */
    gtty(ttyfd,&ttraw);			/* And a copy of it for packets*/
    gtty(ttyfd,&tttvt);			/* And one for virtual tty service */
#else
    ioctl(ttyfd,TCGETA,&ttold);		/* Same deal for Sys III, Sys V */
    ioctl(ttyfd,TCGETA,&ttraw);
    ioctl(ttyfd,TCGETA,&tttvt);
#endif
    debug(F101,"ttopen, ttyfd","",ttyfd);
    debug(F101," lcl","",*lcl);
    debug(F111," lock file",flfnam,lkf);
    return(0);
}

/*  T T C L O S  --  Close the TTY, releasing any lock.  */

ttclos() {
    if (ttyfd < 0) return(0);		/* Wasn't open. */
    if (xlocal) {
	if (tthang())			/* Hang up phone line */
	    fprintf(stderr,"Warning, problem hanging up the phone\n");
    	if (ttunlck())			/* Release uucp-style lock */
	    fprintf(stderr,"Warning, problem releasing lock\n");
    }
    ttres();				/* Reset modes. */
/* Relinquish exclusive access if we might have had it... */
#ifndef XENIX
#ifdef TIOCEXCL
#ifdef TIOCNXCL
    if (ioctl(ttyfd, TIOCNXCL, NULL) < 0)
    	fprintf(stderr,"Warning, problem relinquishing exclusive access\n");
#endif
#endif
#endif
    close(ttyfd);			/* Close it. */
    ttyfd = -1;				/* Mark it as closed. */
    return(0);
}

/*  T T H A N G -- Hangup phone line */

tthang() {
#ifdef UXIII
    unsigned short ttc_save;
#endif

    if (ttyfd < 0) return(0);		/* Not open. */
#ifdef ANYBSD
    ioctl(ttyfd,TIOCCDTR,0);		/* Clear DTR */
    msleep(500);			/* Let things settle */
    ioctl(ttyfd,TIOCSDTR,0);		/* Restore DTR */
#endif
#ifdef UXIII
    ttc_save = ttraw.c_cflag;
    ttraw.c_cflag &= ~CBAUD;		/* swa: set baud rate to 0 to hangup */
    if (ioctl(ttyfd,TCSETAF,&ttraw) < 0) return(-1); /* do it */
    msleep(100);			/* let things settle */
    ttraw.c_cflag = ttc_save;
#ifndef XENIX		/* xenix cannot do close/open when carrier drops */
				/* following corrects a PC/IX defficiency */
    ttc_save = fcntl(ttyfd,F_GETFL,0);
    close(ttyfd);		/* close/reopen file descriptor */
    if ((ttyfd = open(ttnmsv, ttc_save)) < 0) return(-1);
#endif
    if (ioctl(ttyfd,TCSETAF,&ttraw) < 0) return(-1); /* un-do it */
#endif
    return (0);
}


/*  T T R E S  --  Restore terminal to "normal" mode.  */

ttres() {				/* Restore the tty to normal. */
    if (ttyfd < 0) return(-1);		/* Not open. */
#ifndef UXIII				/* except for sIII, */
    sleep(1);				/* Wait for pending i/o to finish. */
#endif					/*   (sIII does wait in ioctls) */
#ifdef KERLD
    if (kerld) ioctl(ttyfd,TIOCSETD,&oldld); /* Restore old line discipline. */
#endif
#ifdef UXIII
    if (ioctl(ttyfd,TCSETAW,&ttold) < 0) return(-1); /* restore termio stuff */
#else
    if (stty(ttyfd,&ttold) < 0) return(-1); /* Restore sgtty stuff */
#endif
#ifdef KERLD
    if (kerld) ioctl(ttyfd,TIOCSETC,&oldc); /* Restore old special chars. */
#endif

    return(0);
}

/* Exclusive uucp file locking control */
/*
 by H. Fischer, creative non-Bell coding !
 copyright rights for lock modules assigned to Columbia University
*/
static char *
xxlast(s,c) char *s; char c; {		/* Equivalent to strrchr() */
    int i;
    for (i = strlen(s); i > 0; i--)
    	if ( s[i-1] == c ) return( s + (i - 1) );
    return(NULL);	    
}
static
look4lk(ttname) char *ttname; {
    extern char *strcat(), *strcpy();
    char *device, *devname;
    char lockfil[50];			/* Max length for lock file name */

#ifdef ISIII
    char *lockdir = "/etc/locks";
#else
#ifdef ATT3BX
    char *lockdir = "/usr/spool/locks";
#else
    char *lockdir = "/usr/spool/uucp";
#endif
#endif

    device = ( (devname=xxlast(ttname,'/')) != NULL ? devname+1 : ttname);

#ifdef ISIII
    (void) strcpy( lockfil, device );
#else
    strcat( strcpy( lockfil, "LCK.." ), device );
#endif

    if (access( lockdir, 04 ) < 0) {	/* read access denied on lock dir */
	fprintf(stderr,"Warning, read access to lock directory denied\n");
	return( 1 );			/* cannot check or set lock file */
    }
	
    strcat(strcat(strcpy(flfnam,lockdir),"/"), lockfil);
    debug(F110,"look4lk",flfnam,0);

    if ( ! access( flfnam, 00 ) ) {	/* print out lock file entry */
	char lckcmd[40] ;
	strcat( strcpy(lckcmd, "ls -l ") , flfnam);
	system(lckcmd);
	if (access(flfnam,02) == 0)
	    printf("(You may type \"! rm %s\" to remove this file)\n",flfnam);
	return( -1 );
    }
    if ( access( lockdir, 02 ) < 0 ) {	/* lock file cannot be written */
	fprintf(stderr,"Warning, write access to lock directory denied\n");
	return( 1 );
    }
    return( 0 );			/* okay to go ahead and lock */
}

/*  T T L O C K  */


static
ttlock(ttyfd) char *ttyfd; {		/* lock uucp if possible */
#ifdef ATT3BX
    FILE *lck_fild;
#endif
    int lck_fil, l4l;
    int pid_buf = getpid();		/* pid to save in lock file */
	
    hasLock = 0;			/* not locked yet */
    l4l = look4lk(ttyfd);
    if (l4l < 0) return (-1);		/* already locked */
    if (l4l == 1) return (0);		/* can't read/write lock directory */
    lck_fil = creat(flfnam, 0444);	/* create lock file ... */
    if (lck_fil < 0) return (-1);	/* create of lockfile failed */
		/* creat leaves file handle open for writing -- hf */
#ifdef ATT3BX
    fprintf((lck_fild = fdopen(lck_fil, "w")), "%10d\n", pid_buf);
    fflush(lck_fild);
#else
    write (lck_fil, &pid_buf, sizeof(pid_buf) ); /* uucp expects int in file */
#endif
    close (lck_fil);
    hasLock = 1;			/* now is locked */
    return(0);
}

/*  T T U N L O C K  */

static
ttunlck() {				/* kill uucp lock if possible */
    if (hasLock) return( unlink( flfnam ) );
}

/*  T T P K T  --  Condition the communication line for packets. */
/*		or for modem dialing */

#define DIALING	4		/* flags (via flow) for modem handling */
#define CONNECT 5

/*  If called with speed > -1, also set the speed.  */

/*  Returns 0 on success, -1 on failure.  */

ttpkt(speed,flow) int speed, flow; {
    int s;
    if (ttyfd < 0) return(-1);		/* Not open. */

#ifdef KERLD
/* Note, KERLD ignores the TANDEM, ECHO, and CRMOD bits */
    if (kerld) {
	ioctl(ttyfd,TIOCGETD,&oldld);	/* Get line discipline */
	ioctl(ttyfd,TIOCGETC,&oldc);	/* Get special chars */
	newc = oldc;			/* Copy special chars */
	newc.t_brkc = '\r';		/* Set CR to be break character */
	if(ioctl(ttyfd,TIOCSETC,&newc) < 0) return(-1);
    }
#endif

    s = ttsspd(speed);			/* Check the speed */

#ifndef UXIII
    if (flow == 1) ttraw.sg_flags |= TANDEM; /* Use XON/XOFF if selected */
    if (flow == 0) ttraw.sg_flags &= ~TANDEM;
    ttraw.sg_flags |= RAW;		/* Go into raw mode */
    ttraw.sg_flags &= ~(ECHO|CRMOD);	/* Use CR for break character */
#ifdef TOWER1
    ttraw.sg_flags &= ~ANYP; 		/* Must tell Tower no parityr */
#endif
    if (s > -1) ttraw.sg_ispeed = ttraw.sg_ospeed = s; /* Do the speed */
    if (stty(ttyfd,&ttraw) < 0) return(-1);	/* Set the new modes. */

#ifdef MYREAD
#ifdef BSD4
/* Try to make reads nonblocking */
    if (kerld == 0) {
	if (fcntl(ttyfd,F_SETFL,fcntl(ttyfd,F_GETFL,0) & FNDELAY) == -1)
    	    return(-1);
	else return(0);
    }
#endif
#endif
#endif

#ifdef UXIII
    if (flow == 1) ttraw.c_iflag |= (IXON|IXOFF);
    if (flow == 0) ttraw.c_iflag &= ~(IXON|IXOFF);

    if (flow == DIALING)  ttraw.c_cflag |= CLOCAL|HUPCL;
    if (flow == CONNECT)  ttraw.c_cflag &= ~CLOCAL;

    ttraw.c_lflag &= ~(ICANON|ECHO);
    ttraw.c_lflag |= ISIG;		/* do check for interrupt */
    ttraw.c_iflag |= (BRKINT|IGNPAR);
    ttraw.c_iflag &= ~(IGNBRK|INLCR|IGNCR|ICRNL|IUCLC|INPCK|ISTRIP|IXANY);
    ttraw.c_oflag &= ~OPOST;
    ttraw.c_cflag &= ~(CSIZE|PARENB);
    ttraw.c_cflag |= (CS8|CREAD);
    ttraw.c_cc[4] = 1;
    ttraw.c_cc[5] = 0;

    if (s > -1) ttraw.c_cflag &= ~CBAUD, ttraw.c_cflag |= s; /* set speed */

    if (ioctl(ttyfd,TCSETAW,&ttraw) < 0) return(-1);  /* set new modes . */
    if (flow == DIALING) {
	if (fcntl(ttyfd,F_SETFL, fcntl(ttyfd, F_GETFL, 0) & ~O_NDELAY) < 0 )
		return(-1);
	close( open(ttnmsv,2) );	/* magic to force mode change!!! */
	}
#endif

#ifdef KERLD
    if (kerld) {
	if (ioctl(ttyfd,TIOCSETD,&ld) < 0)
	    return(-1); /* Set line discpline. */
    }
#endif

    ttflui();				/* Flush any pending input */
    return(0);
}

/*  T T V T -- Condition communication line for use as virtual terminal  */

ttvt(speed,flow) int speed, flow; {
    int s;
    if (ttyfd < 0) return(-1);		/* Not open. */

    s = ttsspd(speed);			/* Check the speed */

#ifndef UXIII
    if (flow == 1) tttvt.sg_flags |= TANDEM; /* XON/XOFF if selected */
    if (flow == 0) tttvt.sg_flags &= ~TANDEM;
    tttvt.sg_flags |= RAW;		/* Raw mode */
#ifdef TOWER1
    tttvt.sg_flags &= ~(ECHO|ANYP);	/* No echo or system III ??? parity */
#else
    tttvt.sg_flags &= ~ECHO;		/* No echo */
#endif    
    if (s > -1) tttvt.sg_ispeed = tttvt.sg_ospeed = s; /* Do the speed */
    if (stty(ttyfd,&tttvt) < 0) return(-1);
#ifdef MYREAD
#ifdef BSD4
/* Make reads nonblocking */
    if (kerld == 0) {
	if (fcntl(ttyfd,F_SETFL,fcntl(ttyfd,F_GETFL,0) & FNDELAY) == -1)
	    return(-1);
	else return(0);
    }
#endif
#endif

#else
    if (flow == 1) tttvt.c_iflag |= (IXON|IXOFF);
    if (flow == 0) tttvt.c_iflag &= ~(IXON|IXOFF);

    if (flow == DIALING)  tttvt.c_cflag |= CLOCAL|HUPCL;
    if (flow == CONNECT)  tttvt.c_cflag &= ~CLOCAL;

    tttvt.c_lflag &= ~(ISIG|ICANON|ECHO);
    tttvt.c_iflag |= (IGNBRK|IGNPAR);
    tttvt.c_iflag &= ~(INLCR|IGNCR|ICRNL|IUCLC|BRKINT|INPCK|ISTRIP|IXANY);
    tttvt.c_oflag &= ~OPOST;
    tttvt.c_cflag &= ~(CSIZE|PARENB);
    tttvt.c_cflag |= (CS8|CREAD);
    tttvt.c_cc[4] = 1;
    tttvt.c_cc[5] = 0;

    if (s > -1) tttvt.c_cflag &= ~CBAUD, tttvt.c_cflag |= s; /* set speed */

    if (ioctl(ttyfd,TCSETAW,&tttvt) < 0) return(-1);  /* set new modes . */
    if (flow == DIALING) {
	if (fcntl(ttyfd,F_SETFL, fcntl(ttyfd, F_GETFL, 0) & ~O_NDELAY) < 0 )
		return(-1);
	close( open(ttnmsv,2) );	/* magic to force mode change!!! */
	}
    return(0);
#endif
}

/*  T T S S P D  --  Return the internal baud rate code for 'speed'.  */

ttsspd(speed) {
    int s, spdok;

    if (speed < 0) return(-1);
	spdok = 1;			/* Assume arg ok */
	switch (speed) {
	    case 0:    s = B0;    break;	/* Just the common ones. */
	    case 110:  s = B110;  break;	/* The others from ttydev.h */
	    case 150:  s = B150;  break;	/* could also be included if */
	    case 300:  s = B300;  break;	/* necessary... */
	    case 600:  s = B600;  break;
	    case 1200: s = B1200; break;
	    case 1800: s = B1800; break;
	    case 2400: s = B2400; break;
	    case 4800: s = B4800; break;
	    case 9600: s = B9600; break;
#ifdef PLEXUS
	    case 19200: s = EXTA; break;
#endif
	    default:
	    	spdok = 0;
		fprintf(stderr,"Unsupported line speed - %d\n",speed);
		fprintf(stderr,"Current speed not changed\n");
		break;
	}	    
	if (spdok) return(s); else return(-1);
 }



/*  T T F L U I  --  Flush tty input buffer */

ttflui() {

#ifndef UXIII
    long n;
#endif
    if (ttyfd < 0) return(-1);		/* Not open. */

    ungotn = -1;			/* Initialize myread() stuff */
    inbufc = 0;

#ifdef UXIII
    if (ioctl(ttyfd,TCFLSH,0) < 0) perror("flush failed");
#else
#ifdef TIOCFLUSH
#ifdef ANYBSD
    n = FREAD;				/* Specify read queue */
    if (ioctl(ttyfd,TIOCFLUSH,&n) < 0) perror("flush failed");
#else
    if (ioctl(ttyfd,TIOCFLUSH,0) < 0) perror("flush failed");
#endif
#endif
#endif
    return(0);
}

/* Interrupt Functions */


/* Timeout handler for communication line input functions */

timerh() {