ckutio.c

linux终端仿真程序

/* leave ttopen() with an error condition. */

    lkf = 0;                            /* Check lock */
    if (xlocal > 0) {
	int xx; int xpid;
        if ((xx = ttlock(ttname)) < 0) { /* Can't lock it. */
            debug(F111,"ttopen ttlock fails",ttname,xx);
	    /* WARNING - This close() can hang if tty is an empty socket... */
            close(ttyfd);		/* Close the device. */
	    ttyfd = -1;			/* Erase its file descriptor. */
	    signal(SIGINT,occt);	/* Put old SIGINT back. */
	    if (xx == -2) {		/* If lockfile says device in use, */
#ifndef NOUUCP
		debug(F111,"ttopen reading lockfile pid",flfnam,xx);
		priv_on();
		xpid = ttrpid(flfnam);	/* Try to read pid from lockfile */
		priv_off();		/* Turn privs back off. */
		if (xpid > -1) {	/* If we got a pid */
		    printf("Locked by process %d\n",xpid); /* tell them. */
		} else if (*flfnam) {
		    char *p = malloc(280); /* Print a directory listing. */
/*
  Note: priv_on() won't help here, because we do not pass privs along to
  to inferior processes, in this case ls.  So if the real user does not have
  directory-listing access to the lockfile directory, this will result in
  something like "not found".  That's why we try this only as a last resort.
*/
		    if (p) {		/* If we got the space... */
			extern char *DIRCMD;
			sprintf(p,"%s %s",DIRCMD,flfnam);
			zsyscmd(p);	/* Get listing. */
			if (p) {	/* free the space */
			    free(p);
			    p = NULL;
			}
		    }
		}
#endif /* NOUUCP */
		return(-5);		/* Code for device in use */
	    } else return(-3);		/* Access denied */
        } else lkf = 1;
    }

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

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

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

#ifdef  V7
#ifndef MINIX
    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 /* !MINIX */
#endif /* V7 */

/* No failure returns after this point */

#ifdef ultrix
    ioctl(ttyfd, TIOCMODEM, &temp);
#ifdef TIOCSINUSE
    if (xlocal && ioctl(ttyfd, TIOCSINUSE, NULL) < 0) {
	fprintf(stderr, "Can't set in-use flag on %s.\n",ttname);
	perror("TIOCSINUSE");
    }
#endif /* TIOCSINUSE */
#endif /* ultrix */

/* Get tty device settings */

#ifdef BSD44ORPOSIX			/* POSIX */
    tcgetattr(ttyfd,&ttold);
    debug(F101,"ttopen tcgetattr ttold.c_lflag","",ttold.c_lflag);
    tcgetattr(ttyfd,&ttraw);
    tcgetattr(ttyfd,&tttvt);
#else					/* BSD, V7, and all others */
#ifdef ATTSV				/* AT&T UNIX */
    ioctl(ttyfd,TCGETA,&ttold);
    debug(F101,"ttopen ioctl TCGETA ttold.c_lflag","",ttold.c_lflag);
    ioctl(ttyfd,TCGETA,&ttraw);
    ioctl(ttyfd,TCGETA,&tttvt);
#else
#ifdef BELLV10
    ioctl(ttyfd,TIOCGETP,&ttold);
    debug(F101,"ttopen BELLV10 ttold.sg_flags","",ttold.sg_flags);
    ioctl(ttyfd,TIOCGDEV,&tdold);
    debug(F101,"ttopen BELLV10 tdold.flags","",tdold.flags);
#else
    gtty(ttyfd,&ttold);
    debug(F101,"ttopen gtty ttold.sg_flags","",ttold.sg_flags);
#endif /* BELLV10 */

#ifdef sony_news			/* Sony NEWS */
    if (ioctl(ttyfd,TIOCKGET,&km_ext) < 0) { /* Get console Kanji mode */
	perror("ttopen error getting Kanji mode");
	debug(F101,"ttopen error getting Kanji mode","",0);
	km_ext = -1;			/* Make sure this stays undefined. */
    }
#endif /* sony_news */

#ifdef TIOCGETC
    tcharf = 0;				/* In remote mode, also get */
    if (xlocal == 0) {			/* special characters */
	if (ioctl(ttyfd,TIOCGETC,&tchold) < 0) {
	    debug(F100,"ttopen TIOCGETC failed","",0);
	} else {
	    tcharf = 1;			/* It worked. */
	    ioctl(ttyfd,TIOCGETC,&tchnoi); /* Get another copy */
	    debug(F100,"ttopen TIOCGETC ok","",0);
	}
    }	
#else
    debug(F100,"ttopen TIOCGETC not defined","",0);
#endif /* TIOCGETC */

#ifdef TIOCGLTC
    ltcharf = 0;			/* In remote mode, also get */
    if (xlocal == 0) {			/* local special characters */
	if (ioctl(ttyfd,TIOCGLTC,&ltchold) < 0) {
	    debug(F100,"ttopen TIOCGLTC failed","",0);
	} else {
	    ltcharf = 1;		/* It worked. */
	    ioctl(ttyfd,TIOCGLTC,&ltchnoi); /* Get another copy */
	    debug(F100,"ttopen TIOCGLTC ok","",0);
	}
    }	
#else
    debug(F100,"ttopen TIOCGLTC not defined","",0);
#endif /* TIOCGLTC */

#ifdef TIOCLGET
    lmodef = 0;
    if (ioctl(ttyfd,TIOCLGET,&lmode) < 0) {
	debug(F100,"ttopen TIOCLGET failed","",0);
    } else {
	lmodef = 1;
	debug(F100,"ttopen TIOCLGET ok","",0);
    }
#endif /* TIOCLGET */

#ifdef BELLV10
    ioctl(ttyfd,TIOCGETP,&ttraw);
    ioctl(ttyfd,TIOCGETP,&tttvt);
#else
    gtty(ttyfd,&ttraw);                 /* And a copy of it for packets*/
    gtty(ttyfd,&tttvt);                 /* And one for virtual tty service */
#endif /* BELLV10 */

#endif /* ATTSV */
#endif /* BSD44ORPOSIX */

/* Section for changing line discipline.  It's restored in ttres(). */

#ifdef AIXRS
#ifndef AIX41
    { union txname ld_name; int ld_idx = 0;
      ttld = 0;
        do {
  	  ld_name.tx_which = ld_idx++;
  	  ioctl(ttyfd, TXGETCD, &ld_name);
	  if (!strncmp(ld_name.tx_name, "rts", 3))
  	    ttld |= 1;
        } while (*ld_name.tx_name);
        debug(F101,"AIX line discipline","",ttld);
      }
#endif /* AIX41 */
#endif /* AIXRS */

#ifdef BSD41
/* For 4.1BSD only, force "old" tty driver, new one botches TANDEM. */
    { int k;
      ioctl(ttyfd, TIOCGETD, &ttld);	/* Get and save line discipline */
      debug(F101,"4.1bsd line discipline","",ttld);
      k = OTTYDISC;			/* Switch to "old" discipline */
      k = ioctl(ttyfd, TIOCSETD, &k);
      debug(F101,"4.1bsd tiocsetd","",k);
    }
#endif /* BSD41 */

#ifdef aegis
    /* This was previously done before the last two TCGETA or gtty above,
     * in both the ATTSV and not-ATTSV case.  If it is not okay to have only
     * one copy if it here instead, give us a shout!
     */
    sio_$control((short)ttyfd, sio_$raw_nl, false, st);
    if (xlocal) {       /* ignore breaks from local line */
        sio_$control((short)ttyfd, sio_$int_enable, false, st);
        sio_$control((short)ttyfd, sio_$quit_enable, false, st);
    }
#endif /* aegis */

#ifdef VXVE
    ttraw.c_line = 0;                   /* STTY line 0 for VX/VE */
    tttvt.c_line = 0;                   /* STTY line 0 for VX/VE */
    ioctl(ttyfd,TCSETA,&ttraw);
#endif /* vxve */

/* If O_NDELAY was used during open(), then remove it now. */

#ifdef O_NDELAY
    if (fcntl(ttyfd, F_GETFL, 0) & O_NDELAY) {

#ifndef aegis
	if (fcntl(ttyfd,F_SETFL, fcntl(ttyfd, F_GETFL, 0) & ~O_NDELAY) < 0 )
	    perror("Can't unset O_NDELAY");
#endif /* aegis */
	/* Some systems, notably Xenix (don't know how common this is in
	 * other systems), need special treatment to get rid of the O_NDELAY
	 * behaviour on read() with respect to carrier presence (i.e. read()
	 * returning 0 when carrier absent), even though the above fcntl()
	 * is enough to make read() wait for input when carrier is present.
	 * This magic, in turn, requires CLOCAL for working when the carrier
	 * is absent. But if xlocal == 0, presumably you already have CLOCAL
	 * or you have a carrier, otherwise you wouldn't be running this.
	 */
#ifdef ATTSV
#ifdef BSD44
#ifdef __bsdi__
	if (xlocal)
	  ttraw.c_cflag |= CLOCAL;
#else
#ifdef __FreeBSD__
	if (xlocal)
	  ttraw.c_cflag |= CLOCAL;
#endif /* __FreeBSD__ */
#endif /* __bsdi__ */
	if (tcsetattr(ttyfd, TCSADRAIN, &ttraw) < 0)
	  perror("tcsetattr");
#else /* !BSD44 */
	if (xlocal) {
	    ttraw.c_cflag |= CLOCAL;
	    ioctl(ttyfd, TCSETA, &ttraw);
	}
#endif /* BSD44 */
#endif /* ATTSV */
#ifndef NOCOTFMC /* = NO Close(Open()) To Force Mode Change */
/* Reportedly lets uugetty grab the device in SCO UNIX 3.2 / XENIX 2.3 */
	close( priv_opn(ttname, O_RDWR) ); /* Magic to force change. */
#endif /* NOCOTFMC */
    }
#endif /* O_NDELAY */

/* Instruct the system how to treat the carrier, and set a few other tty
 * parameters.
 *
 * This also undoes the temporary setting of CLOCAL that may have been done
 * for the close(open()) above (except in Xenix).  Also throw in ~ECHO, to
 * prevent the other end of the line from sitting there talking to itself,
 * producing garbage when the user performs a connect.
 *
 * SCO Xenix unfortunately seems to ignore the actual state of CLOCAL.
 * Now it thinks CLOCAL is always on. It seems the only real solution for
 * Xenix is to switch between the lower and upper case device names.
 *
 * This section may at some future time expand into setting a complete
 * collection of tty parameters, or call a function shared with ttpkt()/
 * ttvt() that does so.  On the other hand, the initial parameters are not
 * that important, since ttpkt() or ttvt() should always fix that before
 * any communication is done.  Well, we'll see...
 */
    if (xlocal) {
    	curcarr = -2;
	carrctl(&ttraw, ttcarr == CAR_ON);

#ifdef COHERENT
#define SVORPOSIX
#endif /* COHERENT */

#ifdef SVORPOSIX
	ttraw.c_lflag &= ~ECHO;
	ttold.c_lflag &= ~ECHO;
#ifdef BSD44ORPOSIX
	tcsetattr(ttyfd, TCSADRAIN, &ttraw);
#else
	ioctl(ttyfd, TCSETA, &ttraw);
#endif /* BSD44ORPOSIX */

#else /* BSD, etc */
	ttraw.sg_flags &= ~ECHO;
	ttold.sg_flags &= ~ECHO;
#ifdef BELLV10
	ioctl(ttyfd,TIOCSETP,&ttraw);
#else
	stty(ttyfd,&ttraw);
#endif /* BELLV10 */
#endif /* SVORPOSIX */

#ifdef COHERENT
#undef SVORPOSIX
#endif /* COHERENT */

	/* ttflui(); */  /*  This fails for some reason.  */
    }
    
    /* Get current speed */

#ifndef BEBOX
    ttspeed = ttgspd();
#else
    ttspeed = 19200;
#endif /* !BEBOX */
    debug(F101,"ttopen ttspeed","",ttspeed);

    /* Done, make entries in debug log, restore Ctrl-C trap, and return. */

    debug(F101,"ttopen, ttyfd","",ttyfd);
    debug(F101," lcl","",*lcl);
    debug(F111," lock file",flfnam,lkf);
    signal(SIGINT,occt);
    return(0);
}


/*  D O _ O P E N  --  Do the right kind of open() call for the tty. */

int
do_open(ttname) char *ttname; {

#ifndef	O_NDELAY			/* O_NDELAY not defined */
    return(priv_opn(ttname,2));
#else					/* O_NDELAY defined */

#ifdef ATT7300
/*
 Open comms line without waiting for carrier so initial call does not hang
 because state of "modem" is likely unknown at the initial call  -jrd.
 If this is needed for the getty stuff to work, and the open would not work
 without O_NDELAY when getty is still on, then this special case is ok.
 Otherwise, get rid of it. -ske
*/
    return(priv_opn(ttname, O_RDWR | O_NDELAY));

#else	/* !ATT7300 */

    /* Normal case. Use O_NDELAY according to SET CARRIER. See ttscarr(). */
  
    return(priv_opn(ttname, O_RDWR | ((ttcarr != CAR_ON) ? O_NDELAY : 0) ));

#endif	/* !ATT7300 */
#endif	/* O_NDELAY */
}

/*  T T C L O S  --  Close the TTY, releasing any lock.  */

int
ttclos(foo) int foo; {			/* Arg req'd for signal() prototype */
    int xx, x = 0;

    debug(F101,"ttclos ttyfd","",ttyfd);
    if (ttyfd < 0) return(0);           /* Wasn't open. */

    if (ttfdflg)			/* If we inherited ttyfd from */
      return(0);			/* another process, don't close it. */

    tvtflg = 0;				/* (some day get rid of this...) */

#ifdef	NETCONN
    if (netconn) {			/* If it's a network connection. */
	debug(F100,"ttclos closing net","",0);
	netclos();			/* Let the network module close it. */
	netconn = 0;			/* No more network connection. */
	debug(F101,"ttclos ttyfd after netclos","",ttyfd);
	return(0);
    }
#endif	/* NETCONN */

    if (xlocal) {			/* We're closing a SET LINE device */
#ifdef FT21				/* Fortune 2.1-specific items ... */
	ioctl(ttyfd,TIOCHPCL, NULL);
#endif /* FT21 */
#ifdef ultrix				/* Ultrix-specific items ... */
#ifdef TIOCSINUSE
	/* Unset the INUSE flag that we set in ttopen() */
	ioctl(ttyfd, TIOCSINUSE, NULL);
#endif /* TIOCSINUSE */
	ioctl(ttyfd, TIOCNMODEM, &x);
#ifdef COMMENT
	/* What was this? */
	ioctl(ttyfd, TIOCNCAR, NULL);
#endif /* COMMENT */
#endif /* ultrix */
	debug(F100,"ttclos about to call ttunlck","",0);
        if (ttunlck())                  /* Release uucp-style lock */
	  fprintf(stderr,"Warning, problem releasing lock\r\n");

    }
    if (
	xlocal
#ifdef NOFDZERO
	|| ttyfd > 0
#endif /* NOFDZERO */
	) {
	saval = signal(SIGALRM,timerh); /* Enable timer interrupt. */
	xx = alarm(8);			/* Allow 8 seconds for this. */
	debug(F101,"ttclos alarm","",xx);
	if (
#ifdef CK_POSIX_SIG
	    sigsetjmp(sjbuf,1)
#else
	    setjmp(sjbuf)
#endif /* CK_POSIX_SIG */
	    ) {				/* Timer went off? */
	    x = -1;
	} else {			/* What we're really trying to do */
	    debug(F100,"ttclos calling tthang()","",0);
	    tthang();			/* Hang up first, then... */
	    debug(F100,"ttclos calling ttres()","",0);
	    ttres();			/* Reset device modes. */
	}
	debug(F101,"ttclos about to call close","",ttyfd);
	close(ttyfd);			/* Close the device. */
	x = 1;
	ttimoff();			/* Turn off timer. */
	if (x < 0) {
	    fprintf(stderr,"?Timed out closing device: %s\n",ttnmsv);
	    debug(F100,"ttclos timed out","",0);
	}
    }

/* For bidirectional lines, restore getty if it was there before. */

    if (xlocal) {

#ifdef ACUCNTRL				/* 4.3BSD acucntrl() method. */
	acucntrl("enable",ttnmsv);	/* Enable getty on the device. */
#else
#ifdef ATT7300				/* ATT UNIX PC (3B1, 7300) method. */
	if (attmodem & DOGETY)		/* Was getty(1m) running before us? */
	  ongetty(ttnmsv);		/* Yes, restart getty on tty line */
	attmodem &= ~DOGETY;		/* No phone in use, getty restored */
#endif /* ATT7300 */
#endif /* System-dependent getty-restoring methods */
    }

#ifdef sony_news
    km_ext = -1;			/* Invalidate device's Kanji-mode */
#endif /* sony_news */

    ttyfd = -1;                         /* Invalidate the file descriptor. */
    debug(F100,"ttclos done","",0);
    return(0);
}

/*  T T H A N G  --  Hangup phone line or network connection.  */
/*
  Returns:
  0 if it does nothing.
  1 if it believes that it hung up successfully.
 -1 if it believes that the hangup attempt failed