ckupty.c

C-Kermit源码。是使用串口/Modem和网络通讯的程序

/*  C K U P T Y  --  C-Kermit pseudoterminal control functions for UNIX  */

/*
  Copyright 1995 by the Massachusetts Institute of Technology.

  Permission to use, copy, modify, and distribute this software and its
  documentation for any purpose and without fee is hereby granted, provided
  that the above copyright notice appear in all copies and that both that
  copyright notice and this permission notice appear in supporting
  documentation, and that the name of M.I.T. not be used in advertising or
  publicity pertaining to distribution of the software without specific,
  written prior permission.  Furthermore if you modify this software you must
  label your software as modified software and not distribute it in such a
  fashion that it might be confused with the original M.I.T. software.
  M.I.T. makes no representations about the suitability of this software for
  any purpose.  It is provided "as is" without express or implied warranty.

  Modified for use in C-Kermit, and new material added, by:

  Jeffrey Altman <[e-mail]>
  The Kermit Project, Columbia University, New York City
  November 1999
*/

/*
  Built and tested successully on:
   . 4.4BSD, including BSDI/OS, NetBSD, FreeBSD, OpenBSD, Mac OS X
   . AIX 4.1 and later
   . DG/UX 5.4R4.11
   . Digital UNIX 3.2 and 4.0
   . HP-UX 9.00 and later
   . IRIX 6.0 and later
   . Linux
   . NeXTSTEP 3.x
   . QNX 4.25 (except PTY process termination not detected)
   . SCO OSR5.0.5
   . SCO Unixware 7
   . SINIX 5.42
   . Solaris 2.x and 7
   . SunOS 4.1.3

  Included but not tested yet in:
   . Macintosh OSX, OpenBSD, and any other BSD44-based system not listed above

  Failures include:
   . SCO UNIX 3.2v4.2 (compile fails with syntax error in <memory.h>)
   . HP-UX 8.00 and earlier (no vhangup or ptsname routines)
*/

#include "ckcdeb.h"			/* To pick up NETPTY definition */

#ifndef NETPTY				/* Selector for PTY support */

char * ptyver = "No PTY support";

#else  /* (rest of this module...) */

char * ptyver = "PTY support 7.0.011, 28 Nov 1999";

/* These will no doubt need adjustment... */

#ifndef NEXT
#define HAVE_SETSID
#endif /* NEXT */
#define HAVE_KILLPG
#define HAVE_TTYNAME
#define HAVE_WAITPID

#ifndef USE_TERMIO
#ifdef LINUX
#define USE_TERMIO
#else
#ifdef ATTSV
#define USE_TERMIO
#else
#ifdef HPUX
#define USE_TERMIO
#else
#ifdef AIX
#define USE_TERMIO
#else
#ifdef BSD44ORPOSIX
#define USE_TERMIO
#else
#ifdef IRIX60
#define USE_TERMIO
#else
#ifdef QNX
#define USE_TERMIO
#endif /* QNX */
#endif /* IRIX60 */
#endif /* BSD44ORPOSIX */
#endif /* AIX */
#endif /* HPUX */
#endif /* ATTSV */
#endif /* LINUX */
#endif /* USE_TERMIO */

#ifdef QNX
#include <fcntl.h>
#endif /* QNX */

#ifdef USE_TERMIO
#define POSIX_TERMIOS			/* Seems to be a misnomer */
#endif /* USE_TERMIO */

#ifdef NEXT
#ifndef GETPGRP_ONEARG
#define GETPGRP_ONEARG
#endif /* GETPGRP_ONEARG */
#endif /* NEXT */

#ifdef WANT_UTMP			/* See ckupty.h */
/*
  WANT_UTMP is not defined because (a) the utmp/wtmp junk is the most
  nonportable part of this module, and (b) we're not logging anybody
  in, we're just running a process, and don't need to write utmp/wtmp records.
*/
#ifndef HAVE_SETUTXENT			/* Who has <utmpx.h> */
#ifdef SOLARIS
#define HAVE_SETUTXENT
#else
#ifdef IRIX60
#define HAVE_SETUTXENT
#else
#ifdef CK_SCOV5
#define HAVE_SETUTXENT
#else
#ifdef HPUX10
#define HAVE_SETUTXENT
#else
#ifdef UNIXWARE
#define HAVE_SETUTXENT
#else
#ifdef IRIX60
#define HAVE_SETUTXENT
#endif /* IRIX60 */
#endif /* UNIXWARE */
#endif /* HPUX10 */
#endif /* CK_SCOV5 */
#endif /* IRIX60 */
#endif /* SOLARIS */
#endif /* HAVE_SETUTXENT */

#ifndef HAVE_UTHOST			/* Does utmp include ut_host[]? */
#ifdef HAVE_SETUTXENT			/* utmpx always does */
#define HAVE_UTHOST
#else
#ifdef LINUX				/* Linux does */
#define HAVE_UTHOST
#else
#ifdef SUNOS4				/* SunOS does */
#define HAVE_UTHOST
#else
#ifdef AIX41				/* AIX 4.1 and later do */
#define HAVE_UTHOST
#endif /* AIX41 */
#endif /* SUNOS4 */
#endif /* LINUX */
#endif /* HAVE_SETUTXENT */
#endif /* HAVE_UTHOST */

#ifndef HAVE_UT_HOST
#ifndef NO_UT_HOST
#define NO_UT_HOST
#endif /* NO_UT_HOST */
#endif /* HAVE_UT_HOST */

#endif /* WANT_UTMP */

#ifdef LINUX
#define CK_VHANGUP
#define HAVE_SYS_SELECT_H
#define HAVE_GETUTENT
#define HAVE_SETUTENT
#define HAVE_UPDWTMP
#endif /* LINUX */

#ifdef HPUX10
#define CK_VHANGUP
#define VHANG_FIRST
#define HAVE_PTSNAME
#ifndef HAVE_PTYTRAP
#define HAVE_PTYTRAP
#endif /* HAVE_PTYTRAP */
#else
#ifdef HPUX9
#define CK_VHANGUP
#define VHANG_FIRST
#define HAVE_PTSNAME
#ifndef HAVE_PTYTRAP
#define HAVE_PTYTRAP
#endif /* HAVE_PTYTRAP */
#endif /* HPUX9 */
#endif /* HPUX10 */

#ifdef SUNOS4
#define CK_VHANGUP
#define NO_UT_PID
#define VHANG_FIRST
#endif /* SUNOS4 */

#ifdef IRIX60
#define CK_VHANGUP
#define HAVE__GETPTY
#endif /* IRIX60 */

#ifdef SINIX
#define HAVE_STREAMS
#define HAVE_GRANTPT
#define HAVE_PTSNAME
#define PUSH_PTEM
#define PUSH_LDTERM
#define PUSH_TTCOMPAT
#endif /* SINIX */

#ifdef ultrix
#define MUST_SETPGRP
#endif /* ultrix */

#ifdef QNX
#define MUST_SETPGRP
#define NO_DEVTTY
#define INIT_SPTY
#endif /* QNX */

#include "ckupty.h"

#ifndef O_NDELAY
#ifdef O_NONBLOCK
#define O_NDELAY O_NONBLOCK
#endif /* O_NONBLOCK */
#endif /* O_NDELAY */

#ifndef ONLCR
#define ONLCR 0
#endif /* ONLCR */

#ifdef CK_WAIT_H
#include <sys/wait.h>
#endif /* CK_WAIT_H */

#ifdef STREAMSPTY
#ifndef INIT_SPTY
#define INIT_SPTY
#endif /* INIT_SPTY */

#include <sys/stream.h>
#include <stropts.h>
#include <termio.h>

/* Make sure we don't get the BSD version */

#ifdef HAVE_SYS_TTY_H
#include "/usr/include/sys/tty.h"
#endif /* HAVE_SYS_TTY_H */

#ifdef HAS_PTYVAR			/* Where is this set? */

#include <sys/ptyvar.h>

#else /* HAS_PTYVAR */

#ifndef TIOCPKT_FLUSHWRITE
#define TIOCPKT_FLUSHWRITE 0x02
#define TIOCPKT_NOSTOP     0x10
#define TIOCPKT_DOSTOP     0x20
#define TIOCPKT_IOCTL      0x40
#endif /* TIOCPKT_FLUSHWRITE */

#endif /* HAS_PTYVAR */

#ifdef HAVE_TTY_H
#include <tty.h>
#endif /* HAVE_TTY_H */
/*
  Because of the way ptyibuf is used with streams messages, we need
  ptyibuf+1 to be on a full-word boundary.  The following weirdness
  is simply to make that happen.
*/
long ptyibufbuf[BUFSIZ/sizeof(long)+1];
char *ptyibuf = ((char *)&ptyibufbuf[1])-1;
char *ptyip = ((char *)&ptyibufbuf[1])-1;
char ptyibuf2[BUFSIZ];
unsigned char ctlbuf[BUFSIZ];
struct strbuf strbufc, strbufd;

int readstream();

#else  /* ! STREAMSPTY */

/* I/O data buffers, pointers, and counters. */

char ptyibuf[BUFSIZ], *ptyip = ptyibuf;
char ptyibuf2[BUFSIZ];

#endif /* ! STREAMSPTY */

#ifndef USE_TERMIO
struct termbuf {
    struct sgttyb sg;
    struct tchars tc;
    struct ltchars ltc;
    int state;
    int lflags;
} termbuf, termbuf2;

#define cfsetospeed(tp,val) (tp)->sg.sg_ospeed = (val)
#define cfsetispeed(tp,val) (tp)->sg.sg_ispeed = (val)
#define cfgetospeed(tp)     (tp)->sg.sg_ospeed
#define cfgetispeed(tp)     (tp)->sg.sg_ispeed

#else  /* USE_TERMIO */

#ifdef SYSV_TERMIO
#define termios termio
#endif /* SYSV_TERMIO */

#ifndef TCSANOW

#ifdef TCSETS

#define TCSANOW TCSETS
#define TCSADRAIN TCSETSW
#define tcgetattr(f, t) ioctl(f, TCGETS, (char *)t)

#else /* TCSETS */

#ifdef TCSETA
#define TCSANOW TCSETA
#define TCSADRAIN TCSETAW
#define tcgetattr(f,t) ioctl(f,TCGETA,(char *)t)
#else /* TCSETA */
#define TCSANOW TIOCSETA
#define TCSADRAIN TIOCSETAW
#define tcgetattr(f,t) ioctl(f,TIOCGETA,(char *)t)
#endif /* TCSETA */

#endif /* TCSETS */

#define tcsetattr(f,a,t) ioctl(f,a,t)
#define cfsetospeed(tp,val) (tp)->c_cflag &= ~CBAUD;(tp)->c_cflag|=(val)
#define cfgetospeed(tp) ((tp)->c_cflag & CBAUD)

#ifdef CIBAUD
#define cfsetispeed(tp,val) \
 (tp)->c_cflag &= ~CIBAUD; (tp)->c_cflag |= ((val)<<IBSHIFT)
#define cfgetispeed(tp) (((tp)->c_cflag & CIBAUD)>>IBSHIFT)
#else /* CIBAUD */
#define cfsetispeed(tp,val) (tp)->c_cflag &= ~CBAUD; (tp)->c_cflag|=(val)
#define cfgetispeed(tp) ((tp)->c_cflag & CBAUD)
#endif /* CIBAUD */

#endif /* TCSANOW */

struct termios termbuf, termbuf2;       /* pty control structure */

#ifdef INIT_SPTY
static int spty = -1;
#endif /* INIT_SPTY */

#endif /* USE_TERMIO */

extern int ttyfd;                       /* Standard Kermit usage */
static int msg = 0;

/* termbuf routines (begin) */
/*
  init_termbuf()
  copy_termbuf(cp)
  set_termbuf()

  These three routines are used to get and set the "termbuf" structure
  to and from the kernel.  init_termbuf() gets the current settings.
  copy_termbuf() hands in a new "termbuf" to write to the kernel, and
  set_termbuf() writes the structure into the kernel.
*/
VOID
init_termbuf() {
    int rc = 0;
    memset(&termbuf,0,sizeof(termbuf));
    memset(&termbuf2,0,sizeof(termbuf2));
#ifndef	USE_TERMIO
    rc = ioctl(ttyfd, TIOCGETP, (char *)&termbuf.sg);
    rc |= ioctl(ttyfd, TIOCGETC, (char *)&termbuf.tc);
    rc |= ioctl(ttyfd, TIOCGLTC, (char *)&termbuf.ltc);
#ifdef TIOCGSTATE
    rc |= ioctl(ttyfd, TIOCGSTATE, (char *)&termbuf.state);
#endif /* TIOCGSTATE */
#else /* USE_TERMIO */
    errno = 0;
#ifdef INIT_SPTY
    rc = tcgetattr(spty, &termbuf);
    debug(F111,"init_termbuf() tcgetattr(spty)",ckitoa(rc),errno);
#else
    rc = tcgetattr(ttyfd, &termbuf);
    debug(F111,"init_termbuf() tcgetattr(ttyfd)",ckitoa(rc),errno);
#endif /* INIT_SPTY */
#endif /* USE_TERMIO */
    if (!rc)
      termbuf2 = termbuf;
}

#ifdef TIOCPKT_IOCTL
VOID
copy_termbuf(cp, len) char *cp; int len; {
    if (len > sizeof(termbuf))
      len = sizeof(termbuf);
    memcpy((char *)&termbuf, cp, len);
    termbuf2 = termbuf;
}
#endif /* TIOCPKT_IOCTL */

VOID
set_termbuf() {				/* Only make the necessary changes. */
#ifndef	USE_TERMIO
    if (memcmp((char *)&termbuf.sg, (char *)&termbuf2.sg, sizeof(termbuf.sg)))
      ioctl(ttyfd, TIOCSETN, (char *)&termbuf.sg);
    if (memcmp((char *)&termbuf.tc, (char *)&termbuf2.tc, sizeof(termbuf.tc)))
      ioctl(ttyfd, TIOCSETC, (char *)&termbuf.tc);
    if (memcmp((char *)&termbuf.ltc, (char *)&termbuf2.ltc,
	       sizeof(termbuf.ltc)))
      ioctl(ttyfd, TIOCSLTC, (char *)&termbuf.ltc);
    if (termbuf.lflags != termbuf2.lflags)
      ioctl(ttyfd, TIOCLSET, (char *)&termbuf.lflags);
#else  /* USE_TERMIO */
    if (memcmp((char *)&termbuf, (char *)&termbuf2, sizeof(termbuf))) {
	int x;
	errno = 0;
#ifdef INIT_SPTY
	x = tcsetattr(spty, TCSANOW, &termbuf);
	debug(F111,"set_termbuf tcsetattr(spty)",ckitoa(x),errno);
#else
	x = tcsetattr(ttyfd, TCSANOW, &termbuf);
	debug(F111,"set_termbuf tcsetattr(ttyfd)",ckitoa(x),errno);
#endif /* INIT_SPTY */
    }
#endif /* USE_TERMIO */
}
/* termbuf routines (end) */

VOID
ptyint_vhangup() {
#ifdef CK_VHANGUP
#ifdef CK_POSIX_SIG
    struct sigaction sa;
    /* Initialize "sa" structure. */
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = 0;
    sa.sa_handler = SIG_IGN;
    sigaction(SIGHUP, &sa, (struct sigaction *)0);
    vhangup();
    sa.sa_handler = SIG_DFL;
    sigaction(SIGHUP, &sa, (struct sigaction *)0);
#else /* CK_POSIX_SIG */
    signal(SIGHUP,SIG_IGN);
    vhangup();
    signal(SIGHUP,SIG_DFL);
#endif /* CK_POSIX_SIG */
#endif /* CK_VHANGUP */
}

/*
  This routine is called twice.  It's not particularly important that the
  setsid() or TIOCSTTY ioctls succeed (they may not the second time), but
  rather that we have a controlling terminal at the end.  It is assumed that
  vhangup doesn't exist and confuse the process's notion of controlling
  terminal on any system without TIOCNOTTY.  That is, either vhangup() leaves
  the controlling terminal in tact, breaks the association completely, or the
  system provides TIOCNOTTY to get things back into a reasonable state.  In
  practice, vhangup() either breaks the association completely or doesn't
  effect controlling terminals, so this condition is met.
*/
long
ptyint_void_association() {
    int con_fd;
#ifdef HAVE_SETSID
    debug(F110,
	  "ptyint_void_association()",
	  "setsid()",
	  0
	  );
    setsid();
#endif /* HAVE_SETSID */

#ifndef NO_DEVTTY
    /* Void tty association first */
#ifdef TIOCNOTTY
    con_fd = open("/dev/tty", O_RDWR);
    debug(F111,
	  "ptyint_void_association() open(/dev/tty,O_RDWR)",
	  "/dev/tty",
	  con_fd);
    if (con_fd >= 0) {
        ioctl(con_fd, TIOCNOTTY, 0);
        close(con_fd);
    }
#endif /* TIOCNOTTY */
#endif /* NO_DEVTTY */
    return(0);
}

/* PID may be zero for unknown.*/

long
pty_cleanup(slave, pid, update_utmp) char *slave; int pid; int update_utmp; {
    int retval, fd;

    debug(F111,"pty_cleanup()",slave,pid);
#ifdef WANT_UTMP
    if (update_utmp)
      pty_update_utmp(PTY_DEAD_PROCESS,
		      0,
		      "",
		      slave,
		      (char *)0,
		      PTY_UTMP_USERNAME_VALID
		      );
#endif /* WANT_UTMP */

#ifdef SETUID
    chmod(slave, 0666);
    chown(slave, 0, 0);
#endif /* SETUID */

#ifdef HAVE_REVOKE
    revoke(slave);
    /*
       Revoke isn't guaranteed to send a SIGHUP to the processes it
       dissociates from the terminal.  The best solution without a Posix
       mechanism for forcing a hangup is to killpg() the process group of the
       pty.  This will at least kill the shell and hopefully, the child
       processes.  This is not always the case, however.  If the shell puts
       each job in a process group and doesn't pass along SIGHUP, all
       processes may not die.
    */
    if (pid > 0) {
#ifdef HAVE_KILLPG
	killpg(pid, SIGHUP);
#else
	kill(-(pid), SIGHUP);
#endif /*HAVE_KILLPG*/
    }
#else /* HAVE_REVOKE*/
#ifdef VHANG_LAST
    {
        int status;
#ifdef CK_POSIX_SIG
        sigset_t old, new;
        sigemptyset(&new);
        sigaddset(&new, SIGCHLD);
        sigprocmask(SIG_BLOCK, &new, &old);
#else /*CK_POSIX_SIG*/
        int mask = sigblock(sigmask(SIGCHLD));
#endif /*CK_POSIX_SIG*/
        switch (retval = fork()) {
	  case -1:
#ifdef CK_POSIX_SIG
            sigprocmask(SIG_SETMASK, &old, 0);
#else /*CK_POSIX_SIG*/
            sigsetmask(mask);
#endif /*CK_POSIX_SIG*/
            return errno;
	  case 0:
            ptyint_void_association();
            if (retval = (pty_open_ctty(slave, &fd)))
	      exit(retval);
            ptyint_vhangup();
            exit(0);
	    break;