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/*
* pty_open_slave: open slave side of terminal, clearing for use.
*
* Copyright 1995, 1996, 2001 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.
*
*/
#include <com_err.h>
#include "libpty.h"
#include "pty-int.h"
long
pty_open_slave(const char *slave, int *fd)
{
int tmpfd;
long retval;
/* Sanity check. */
if (slave == NULL || *slave == '\0')
return PTY_OPEN_SLAVE_TOOSHORT;
/* First, set up a new session and void old associations. */
ptyint_void_association();
/*
* Make a first attempt at acquiring the ctty under certain
* condisions. This is necessary for several reasons:
*
* Under Irix, if you open a pty slave and then close it, a
* subsequent open of the slave will cause the master to read EOF.
* To prevent this, don't close the first fd until we do the real
* open following vhangup().
*
* Under Tru64 v5.0, if there isn't a fd open on the slave,
* revoke() fails with ENOTTY, curiously enough.
*
* Anyway, sshd seems to make a practice of doing this.
*/
#if defined(VHANG_FIRST) || defined(REVOKE_NEEDS_OPEN)
retval = pty_open_ctty(slave, fd);
if (retval)
return retval;
if (*fd < 0)
return PTY_OPEN_SLAVE_OPENFAIL;
#endif
/* chmod and chown the slave. */
if (chmod(slave, 0))
return PTY_OPEN_SLAVE_CHMODFAIL;
if (chown(slave, 0, 0) == -1)
return PTY_OPEN_SLAVE_CHOWNFAIL;
#ifdef HAVE_REVOKE
if (revoke(slave) < 0) {
return PTY_OPEN_SLAVE_REVOKEFAIL;
}
#else /* !HAVE_REVOKE */
#ifdef VHANG_FIRST
ptyint_vhangup();
#endif
#endif /* !HAVE_REVOKE */
/* Open the pty for real. */
retval = pty_open_ctty(slave, &tmpfd);
#if defined(VHANG_FIRST) || defined(REVOKE_NEEDS_OPEN)
close(*fd);
#endif
if (retval) {
*fd = -1;
return PTY_OPEN_SLAVE_OPENFAIL;
}
*fd = tmpfd;
retval = pty_initialize_slave(*fd);
if (retval)
return retval;
/* Make sure it's really our ctty. */
tmpfd = open("/dev/tty", O_RDWR|O_NDELAY);
if (tmpfd < 0) {
close(*fd);
*fd = -1;
return PTY_OPEN_SLAVE_NOCTTY;
}
close(tmpfd);
return 0;
}
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