rxvt-unicode/src/ptytty.C

/*--------------------------------*-C-*---------------------------------*
 * File:        ptytty.C
 *----------------------------------------------------------------------*
 *
 * All portions of code are copyright by their respective author/s.
 * Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com>
 * Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *---------------------------------------------------------------------*/

#include "../config.h"          /* NECESSARY */
#include "rxvt.h"

#include <cstdlib>
#include <cstring>

#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <fcntl.h>

#ifdef HAVE_SYS_IOCTL_H
# include <sys/ioctl.h>
#endif
#if defined(PTYS_ARE_PTMX) && defined(HAVE_SYS_STROPTS_H)
# include <sys/stropts.h>      /* for I_PUSH */
#endif
#ifdef HAVE_ISASTREAM
# include <stropts.h>
#endif
#if defined(HAVE_PTY_H)
# include <pty.h>
#elif defined(HAVE_LIBUTIL_H)
# include <libutil.h>
#elif defined(HAVE_UTIL_H)
# include <util.h>
#endif

#include <cstdio>
#include <grp.h>

#include "rxvtutil.h"
#include "fdpass.h"
#include "ptytty.h"

/////////////////////////////////////////////////////////////////////////////

/* ------------------------------------------------------------------------- *
 *                  GET PSEUDO TELETYPE - MASTER AND SLAVE                   *
 * ------------------------------------------------------------------------- */
/*
 * Returns pty file descriptor, or -1 on failure 
 * If successful, ttydev is set to the name of the slave device.
 * fd_tty _may_ also be set to an open fd to the slave device
 */
static inline int
get_pty_streams (int *fd_tty, char **ttydev)
{
#if defined(HAVE_GRANTPT) && defined(HAVE_UNLOCKPT)
# if defined(PTYS_ARE_GETPT) || defined(PTYS_ARE_POSIX) || defined(PTYS_ARE_PTMX)
  int pfd;

# if defined(PTYS_ARE_GETPT)
  pfd = getpt();
# elif defined(PTYS_ARE_POSIX)
  pfd = posix_openpt (O_RDWR);
# else
  pfd = open ("/dev/ptmx", O_RDWR | O_NOCTTY, 0);
# endif
  if (pfd >= 0)
    {
      if (grantpt (pfd) == 0    /* change slave permissions */
          && unlockpt (pfd) == 0)
        {       /* slave now unlocked */
          *ttydev = strdup (ptsname (pfd));     /* get slave's name */
          return pfd;
        }

      close (pfd);
    }
# endif
#endif

  return -1;
}

static inline int
get_pty_openpty (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_OPENPTY
  int pfd;
  int res;
  char tty_name[sizeof "/dev/pts/????\0"];
  
  res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
  if (res != -1)
    {
      *ttydev = strdup (tty_name);
      return pfd;
    }
#endif

  return -1;
}

static inline int
get_pty__getpty (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE__GETPTY
  int pfd;

  *ttydev = _getpty (&pfd, O_RDWR | O_NONBLOCK | O_NOCTTY, 0622, 0);
  if (*ttydev != NULL)
    return pfd;
#endif

  return -1;
}

static inline int
get_pty_ptc (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_PTC
  int pfd;

  if ((pfd = open ("/dev/ptc", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ttyname (pfd));
      return pfd;
    }
#endif

  return -1;
}

static inline int
get_pty_clone (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_CLONE
  int pfd;

  if ((pfd = open ("/dev/ptym/clone", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ptsname (pfd));
      return pfd;
    }
#endif

  return -1;
}

static inline int
get_pty_numeric (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_NUMERIC
  int pfd;
  int idx;
  char *c1, *c2;
  char pty_name[] = "/dev/ptyp???";
  char tty_name[] = "/dev/ttyp???";

  c1 = &(pty_name[sizeof (pty_name) - 4]);
  c2 = &(tty_name[sizeof (tty_name) - 4]);

  for (idx = 0; idx < 256; idx++)
    {
      sprintf (c1, "%d", idx);
      sprintf (c2, "%d", idx);

      if (access (tty_name, F_OK) < 0)
        {
          idx = 256;
          break;
        }

      if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) >= 0)
        {
          if (access (tty_name, R_OK | W_OK) == 0)
            {
              *ttydev = strdup (tty_name);
              return pfd;
            }

          close (pfd);
        }
    }
#endif

  return -1;
}

static inline int
get_pty_searched (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_SEARCHED
# ifndef PTYCHAR1
#  define PTYCHAR1      "pqrstuvwxyz"
# endif
# ifndef PTYCHAR2
#  define PTYCHAR2      "0123456789abcdef"
# endif
  int pfd;
  const char *c1, *c2;
  char pty_name[] = "/dev/pty??";
  char tty_name[] = "/dev/tty??";

  for (c1 = PTYCHAR1; *c1; c1++)
    {
      pty_name[ (sizeof (pty_name) - 3)] =
        tty_name[ (sizeof (pty_name) - 3)] = *c1;

      for (c2 = PTYCHAR2; *c2; c2++)
        {
          pty_name[ (sizeof (pty_name) - 2)] =
            tty_name[ (sizeof (pty_name) - 2)] = *c2;

          if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) >= 0)
            {
              if (access (tty_name, R_OK | W_OK) == 0)
                {
                  *ttydev = strdup (tty_name);
                  return pfd;
                }

              close (pfd);
            }
        }
    }
#endif

  return -1;
}

static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

  if ((pfd = get_pty_streams (fd_tty, ttydev)) != -1
      || (pfd = get_pty_openpty (fd_tty, ttydev)) != -1
      || (pfd = get_pty__getpty (fd_tty, ttydev)) != -1
      || (pfd = get_pty_ptc (fd_tty, ttydev)) != -1
      || (pfd = get_pty_clone (fd_tty, ttydev)) != -1
      || (pfd = get_pty_numeric (fd_tty, ttydev)) != -1
      || (pfd = get_pty_searched (fd_tty, ttydev)) != -1)
    return pfd;

  return -1;
}

/*----------------------------------------------------------------------*/
/*
 * Returns tty file descriptor, or -1 on failure 
 */
static int
get_tty (char *ttydev)
{
  return open (ttydev, O_RDWR | O_NOCTTY, 0);
}

/*----------------------------------------------------------------------*/
/*
 * Make our tty a controlling tty so that /dev/tty points to us
 */
static int
control_tty (int fd_tty)
{
  setsid ();

#if defined(PTYS_ARE_PTMX) && defined(I_PUSH)
  /*
   * Push STREAMS modules:
   *    ptem: pseudo-terminal hardware emulation module.
   *    ldterm: standard terminal line discipline.
   *    ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
   *
   * After we push the STREAMS modules, the first open () on the slave side
   * (i.e. the next section between the dashes giving us "tty opened OK")
   * should make the "ptem" (or "ldterm" depending upon either which OS
   * version or which set of manual pages you have) module give us a
   * controlling terminal.  We must already have close ()d the master side
   * fd in this child process before we push STREAMS modules on because the
   * documentation is really unclear about whether it is any close () on
   * the master side or the last close () - i.e. a proper STREAMS dismantling
   * close () - on the master side which causes a hang up to be sent
   * through - Geoff Wing
   */
# ifdef HAVE_ISASTREAM
  if (isastream (fd_tty) == 1)
# endif
    {
      ioctl (fd_tty, I_PUSH, "ptem");
      ioctl (fd_tty, I_PUSH, "ldterm");
      ioctl (fd_tty, I_PUSH, "ttcompat");
    }
#endif

  ioctl (fd_tty, TIOCSCTTY, NULL);

  int fd = open ("/dev/tty", O_WRONLY);
  if (fd < 0)
    return -1;          /* fatal */

  close (fd);

  return 0;
}

void
rxvt_ptytty::close_tty ()
{
  if (tty < 0)
    return;

  close (tty);
  tty = -1;
}

bool
rxvt_ptytty::make_controlling_tty ()
{
  return control_tty (tty) >= 0;
}

void
rxvt_ptytty::set_utf8_mode (bool on)
{
#ifdef IUTF8
  if (pty < 0)
    return;

  struct termios tio;

  if (tcgetattr (pty, &tio) != -1)
    {
      tcflag_t new_cflag = tio.c_iflag;

      if (on)
        new_cflag |= IUTF8;
      else
        new_cflag &= ~IUTF8;

      if (new_cflag != tio.c_iflag)
        {
          tio.c_iflag = new_cflag;
          tcsetattr (pty, TCSANOW, &tio);
        }
    }
#endif
}

static struct ttyconf {
  gid_t gid;
  mode_t mode;

  ttyconf ()
    {
#ifdef TTY_GID_SUPPORT
      struct group *gr = getgrnam ("tty");

      if (gr)
        {           /* change group ownership of tty to "tty" */
          mode = S_IRUSR | S_IWUSR | S_IWGRP;
          gid = gr->gr_gid;
        }
      else
#endif                          /* TTY_GID_SUPPORT */
        {
          mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH;
          gid = 0;
        }
    }
} ttyconf;

rxvt_ptytty_unix::rxvt_ptytty_unix ()
{
  pty = tty = -1;
  name = 0;
#if UTMP_SUPPORT
  cmd_pid = 0;
#endif
}

rxvt_ptytty_unix::~rxvt_ptytty_unix ()
{
#if UTMP_SUPPORT
  logout ();
#endif
  put ();
}

void
rxvt_ptytty_unix::put ()
{
  chmod (name, RESTORE_TTY_MODE);
  chown (name, 0, ttyconf.gid);

  close_tty ();

  if (pty >= 0)
    close (pty);

  free (name);

  pty = tty = -1;
  name = 0;
}

bool
rxvt_ptytty_unix::get ()
{
  /* get master (pty) */
  if ((pty = get_pty (&tty, &name)) < 0)
    return false;

  fcntl (pty, F_SETFL, O_NONBLOCK);

  /* get slave (tty) */
  if (tty < 0)
    {
#ifndef NO_SETOWNER_TTYDEV
      chown (name, getuid (), ttyconf.gid);      /* fail silently */
      chmod (name, ttyconf.mode);
# ifdef HAVE_REVOKE
      revoke (name);
# endif
#endif

      if ((tty = get_tty (name)) < 0)
        {
          put ();
          return false;
        }
    }

  return true;
}

#if PTYTTY_HELPER

static int sock_fd;
static int pid;

struct command
{
  enum { get, login, destroy } type;

  rxvt_ptytty *id;

  bool login_shell;
  int cmd_pid;
  char hostname[512]; // arbitrary, but should be plenty
};

struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
{
  rxvt_ptytty *id;

  ~rxvt_ptytty_proxy ();

  bool get ();
  void login (int cmd_pid, bool login_shell, const char *hostname);
};

bool
rxvt_ptytty_proxy::get ()
{
  command cmd;

  cmd.type = command::get;

  write (sock_fd, &cmd, sizeof (cmd));

  if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
    rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");

  if (!id)
    return false;

  if ((pty = rxvt_recv_fd (sock_fd)) < 0
      || (tty = rxvt_recv_fd (sock_fd)) < 0)
    rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");

  return true;
}

void
rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
{
  command cmd;

  cmd.type = command::login;
  cmd.id = id;
  cmd.cmd_pid = cmd_pid;
  cmd.login_shell = login_shell;
  strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));

  write (sock_fd, &cmd, sizeof (cmd));
}

rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
{
  command cmd;

  cmd.type = command::destroy;
  cmd.id = id;

  write (sock_fd, &cmd, sizeof (cmd));
}

static
void serve ()
{
  command cmd;
  vector<rxvt_ptytty *> ptys;

  while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
    {
      if (cmd.type == command::get)
        {
          // -> id ptyfd ttyfd
          cmd.id = new rxvt_ptytty_unix;

          if (cmd.id->get ())
            {
              write (sock_fd, &cmd.id, sizeof (cmd.id));
              ptys.push_back (cmd.id);

              rxvt_send_fd (sock_fd, cmd.id->pty);
              rxvt_send_fd (sock_fd, cmd.id->tty);
            }
          else
            {
              delete cmd.id;
              cmd.id = 0;
              write (sock_fd, &cmd.id, sizeof (cmd.id));
            }
        }
      else if (cmd.type == command::login)
        {
#if UTMP_SUPPORT
          if (find (ptys.begin (), ptys.end (), cmd.id))
            {
              cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
              cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
            }
#endif
        }
      else if (cmd.type == command::destroy)
        {
          rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);

          if (pty)
            {
              delete *pty;
              ptys.erase (pty);
            }
        }
      else
        break;
    }

  // destroy all ptys
  for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
    delete *i;
}

void rxvt_ptytty_server ()
{
  int sv[2];

  if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
    rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");

  pid = fork ();

  if (pid < 0)
    rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");

  if (pid)
    {
      // client, urxvt
      sock_fd = sv[0];
      close (sv[1]);
      fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
    }
  else
    {
      // server, pty-helper
      sock_fd = sv[1];

      for (int fd = 0; fd < 1023; fd++)
        if (fd != sock_fd)
          close (fd);

      serve ();
      _exit (EXIT_SUCCESS);
    }
}

#endif

// a "factory" *g*
rxvt_ptytty *
rxvt_new_ptytty ()
{
#if PTYTTY_HELPER
  if (pid > 0)
    // use helper process
    return new rxvt_ptytty_proxy;
  else
#endif
    return new rxvt_ptytty_unix;
}

/*----------------------- end-of-file (C source) -----------------------*/

Revision:	1.50
Committed:	Thu Jan 19 16:43:36 2006 UTC (18 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.49:	+5 -1 lines
Log Message:	* empty log message *
#	Content
1	/---------------------------------C----------------------------------
2	* File: ptytty.C
3	----------------------------------------------------------------------
4	*
5	* All portions of code are copyright by their respective author/s.
6	* Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com>
7	* Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
8	*
9	* This program is free software; you can redistribute it and/or modify
10	* it under the terms of the GNU General Public License as published by
11	* the Free Software Foundation; either version 2 of the License, or
12	* (at your option) any later version.
13	*
14	* This program is distributed in the hope that it will be useful,
15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17	* GNU General Public License for more details.
18	*
19	* You should have received a copy of the GNU General Public License
20	* along with this program; if not, write to the Free Software
21	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22	---------------------------------------------------------------------/
23
24	#include "../config.h" /* NECESSARY */
25	#include "rxvt.h"
26
27	#include <cstdlib>
28	#include <cstring>
29
30	#include <sys/types.h>
31	#include <sys/socket.h>
32	#include <unistd.h>
33	#include <fcntl.h>
34
35	#ifdef HAVE_SYS_IOCTL_H
36	# include <sys/ioctl.h>
37	#endif
38	#if defined(PTYS_ARE_PTMX) && defined(HAVE_SYS_STROPTS_H)
39	# include <sys/stropts.h> /* for I_PUSH */
40	#endif
41	#ifdef HAVE_ISASTREAM
42	# include <stropts.h>
43	#endif
44	#if defined(HAVE_PTY_H)
45	# include <pty.h>
46	#elif defined(HAVE_LIBUTIL_H)
47	# include <libutil.h>
48	#elif defined(HAVE_UTIL_H)
49	# include <util.h>
50	#endif
51
52	#include <cstdio>
53	#include <grp.h>
54
55	#include "rxvtutil.h"
56	#include "fdpass.h"
57	#include "ptytty.h"
58
59	/////////////////////////////////////////////////////////////////////////////
60
61	/* ------------------------------------------------------------------------- *
62	* GET PSEUDO TELETYPE - MASTER AND SLAVE *
63	* ------------------------------------------------------------------------- */
64	/*
65	* Returns pty file descriptor, or -1 on failure
66	* If successful, ttydev is set to the name of the slave device.
67	* fd_tty _may_ also be set to an open fd to the slave device
68	*/
69	static inline int
70	get_pty_streams (int fd_tty, char *ttydev)
71	{
72	#if defined(HAVE_GRANTPT) && defined(HAVE_UNLOCKPT)
73	# if defined(PTYS_ARE_GETPT) \|\| defined(PTYS_ARE_POSIX) \|\| defined(PTYS_ARE_PTMX)
74	int pfd;
75
76	# if defined(PTYS_ARE_GETPT)
77	pfd = getpt();
78	# elif defined(PTYS_ARE_POSIX)
79	pfd = posix_openpt (O_RDWR);
80	# else
81	pfd = open ("/dev/ptmx", O_RDWR \| O_NOCTTY, 0);
82	# endif
83	if (pfd >= 0)
84	{
85	if (grantpt (pfd) == 0 /* change slave permissions */
86	&& unlockpt (pfd) == 0)
87	{ /* slave now unlocked */
88	ttydev = strdup (ptsname (pfd)); / get slave's name */
89	return pfd;
90	}
91
92	close (pfd);
93	}
94	# endif
95	#endif
96
97	return -1;
98	}
99
100	static inline int
101	get_pty_openpty (int fd_tty, char *ttydev)
102	{
103	#ifdef PTYS_ARE_OPENPTY
104	int pfd;
105	int res;
106	char tty_name[sizeof "/dev/pts/????\0"];
107
108	res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
109	if (res != -1)
110	{
111	*ttydev = strdup (tty_name);
112	return pfd;
113	}
114	#endif
115
116	return -1;
117	}
118
119	static inline int
120	get_pty__getpty (int fd_tty, char *ttydev)
121	{
122	#ifdef PTYS_ARE__GETPTY
123	int pfd;
124
125	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
126	if (*ttydev != NULL)
127	return pfd;
128	#endif
129
130	return -1;
131	}
132
133	static inline int
134	get_pty_ptc (int fd_tty, char *ttydev)
135	{
136	#ifdef PTYS_ARE_PTC
137	int pfd;
138
139	if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
140	{
141	*ttydev = strdup (ttyname (pfd));
142	return pfd;
143	}
144	#endif
145
146	return -1;
147	}
148
149	static inline int
150	get_pty_clone (int fd_tty, char *ttydev)
151	{
152	#ifdef PTYS_ARE_CLONE
153	int pfd;
154
155	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
156	{
157	*ttydev = strdup (ptsname (pfd));
158	return pfd;
159	}
160	#endif
161
162	return -1;
163	}
164
165	static inline int
166	get_pty_numeric (int fd_tty, char *ttydev)
167	{
168	#ifdef PTYS_ARE_NUMERIC
169	int pfd;
170	int idx;
171	char c1, c2;
172	char pty_name[] = "/dev/ptyp???";
173	char tty_name[] = "/dev/ttyp???";
174
175	c1 = &(pty_name[sizeof (pty_name) - 4]);
176	c2 = &(tty_name[sizeof (tty_name) - 4]);
177
178	for (idx = 0; idx < 256; idx++)
179	{
180	sprintf (c1, "%d", idx);
181	sprintf (c2, "%d", idx);
182
183	if (access (tty_name, F_OK) < 0)
184	{
185	idx = 256;
186	break;
187	}
188
189	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
190	{
191	if (access (tty_name, R_OK \| W_OK) == 0)
192	{
193	*ttydev = strdup (tty_name);
194	return pfd;
195	}
196
197	close (pfd);
198	}
199	}
200	#endif
201
202	return -1;
203	}
204
205	static inline int
206	get_pty_searched (int fd_tty, char *ttydev)
207	{
208	#ifdef PTYS_ARE_SEARCHED
209	# ifndef PTYCHAR1
210	# define PTYCHAR1 "pqrstuvwxyz"
211	# endif
212	# ifndef PTYCHAR2
213	# define PTYCHAR2 "0123456789abcdef"
214	# endif
215	int pfd;
216	const char c1, c2;
217	char pty_name[] = "/dev/pty??";
218	char tty_name[] = "/dev/tty??";
219
220	for (c1 = PTYCHAR1; *c1; c1++)
221	{
222	pty_name[ (sizeof (pty_name) - 3)] =
223	tty_name[ (sizeof (pty_name) - 3)] = *c1;
224
225	for (c2 = PTYCHAR2; *c2; c2++)
226	{
227	pty_name[ (sizeof (pty_name) - 2)] =
228	tty_name[ (sizeof (pty_name) - 2)] = *c2;
229
230	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
231	{
232	if (access (tty_name, R_OK \| W_OK) == 0)
233	{
234	*ttydev = strdup (tty_name);
235	return pfd;
236	}
237
238	close (pfd);
239	}
240	}
241	}
242	#endif
243
244	return -1;
245	}
246
247	static int
248	get_pty (int fd_tty, char *ttydev)
249	{
250	int pfd;
251
252	if ((pfd = get_pty_streams (fd_tty, ttydev)) != -1
253	\|\| (pfd = get_pty_openpty (fd_tty, ttydev)) != -1
254	\|\| (pfd = get_pty__getpty (fd_tty, ttydev)) != -1
255	\|\| (pfd = get_pty_ptc (fd_tty, ttydev)) != -1
256	\|\| (pfd = get_pty_clone (fd_tty, ttydev)) != -1
257	\|\| (pfd = get_pty_numeric (fd_tty, ttydev)) != -1
258	\|\| (pfd = get_pty_searched (fd_tty, ttydev)) != -1)
259	return pfd;
260
261	return -1;
262	}
263
264	/----------------------------------------------------------------------/
265	/*
266	* Returns tty file descriptor, or -1 on failure
267	*/
268	static int
269	get_tty (char *ttydev)
270	{
271	return open (ttydev, O_RDWR \| O_NOCTTY, 0);
272	}
273
274	/----------------------------------------------------------------------/
275	/*
276	* Make our tty a controlling tty so that /dev/tty points to us
277	*/
278	static int
279	control_tty (int fd_tty)
280	{
281	setsid ();
282
283	#if defined(PTYS_ARE_PTMX) && defined(I_PUSH)
284	/*
285	* Push STREAMS modules:
286	* ptem: pseudo-terminal hardware emulation module.
287	* ldterm: standard terminal line discipline.
288	* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
289	*
290	* After we push the STREAMS modules, the first open () on the slave side
291	* (i.e. the next section between the dashes giving us "tty opened OK")
292	* should make the "ptem" (or "ldterm" depending upon either which OS
293	* version or which set of manual pages you have) module give us a
294	* controlling terminal. We must already have close ()d the master side
295	* fd in this child process before we push STREAMS modules on because the
296	* documentation is really unclear about whether it is any close () on
297	* the master side or the last close () - i.e. a proper STREAMS dismantling
298	* close () - on the master side which causes a hang up to be sent
299	* through - Geoff Wing
300	*/
301	# ifdef HAVE_ISASTREAM
302	if (isastream (fd_tty) == 1)
303	# endif
304	{
305	ioctl (fd_tty, I_PUSH, "ptem");
306	ioctl (fd_tty, I_PUSH, "ldterm");
307	ioctl (fd_tty, I_PUSH, "ttcompat");
308	}
309	#endif
310
311	ioctl (fd_tty, TIOCSCTTY, NULL);
312
313	int fd = open ("/dev/tty", O_WRONLY);
314	if (fd < 0)
315	return -1; /* fatal */
316
317	close (fd);
318
319	return 0;
320	}
321
322	void
323	rxvt_ptytty::close_tty ()
324	{
325	if (tty < 0)
326	return;
327
328	close (tty);
329	tty = -1;
330	}
331
332	bool
333	rxvt_ptytty::make_controlling_tty ()
334	{
335	return control_tty (tty) >= 0;
336	}
337
338	void
339	rxvt_ptytty::set_utf8_mode (bool on)
340	{
341	#ifdef IUTF8
342	if (pty < 0)
343	return;
344
345	struct termios tio;
346
347	if (tcgetattr (pty, &tio) != -1)
348	{
349	tcflag_t new_cflag = tio.c_iflag;
350
351	if (on)
352	new_cflag \|= IUTF8;
353	else
354	new_cflag &= ~IUTF8;
355
356	if (new_cflag != tio.c_iflag)
357	{
358	tio.c_iflag = new_cflag;
359	tcsetattr (pty, TCSANOW, &tio);
360	}
361	}
362	#endif
363	}
364
365	static struct ttyconf {
366	gid_t gid;
367	mode_t mode;
368
369	ttyconf ()
370	{
371	#ifdef TTY_GID_SUPPORT
372	struct group *gr = getgrnam ("tty");
373
374	if (gr)
375	{ /* change group ownership of tty to "tty" */
376	mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
377	gid = gr->gr_gid;
378	}
379	else
380	#endif /* TTY_GID_SUPPORT */
381	{
382	mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
383	gid = 0;
384	}
385	}
386	} ttyconf;
387
388	rxvt_ptytty_unix::rxvt_ptytty_unix ()
389	{
390	pty = tty = -1;
391	name = 0;
392	#if UTMP_SUPPORT
393	cmd_pid = 0;
394	#endif
395	}
396
397	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
398	{
399	#if UTMP_SUPPORT
400	logout ();
401	#endif
402	put ();
403	}
404
405	void
406	rxvt_ptytty_unix::put ()
407	{
408	chmod (name, RESTORE_TTY_MODE);
409	chown (name, 0, ttyconf.gid);
410
411	close_tty ();
412
413	if (pty >= 0)
414	close (pty);
415
416	free (name);
417
418	pty = tty = -1;
419	name = 0;
420	}
421
422	bool
423	rxvt_ptytty_unix::get ()
424	{
425	/* get master (pty) */
426	if ((pty = get_pty (&tty, &name)) < 0)
427	return false;
428
429	fcntl (pty, F_SETFL, O_NONBLOCK);
430
431	/* get slave (tty) */
432	if (tty < 0)
433	{
434	#ifndef NO_SETOWNER_TTYDEV
435	chown (name, getuid (), ttyconf.gid); /* fail silently */
436	chmod (name, ttyconf.mode);
437	# ifdef HAVE_REVOKE
438	revoke (name);
439	# endif
440	#endif
441
442	if ((tty = get_tty (name)) < 0)
443	{
444	put ();
445	return false;
446	}
447	}
448
449	return true;
450	}
451
452	#if PTYTTY_HELPER
453
454	static int sock_fd;
455	static int pid;
456
457	struct command
458	{
459	enum { get, login, destroy } type;
460
461	rxvt_ptytty *id;
462
463	bool login_shell;
464	int cmd_pid;
465	char hostname[512]; // arbitrary, but should be plenty
466	};
467
468	struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
469	{
470	rxvt_ptytty *id;
471
472	~rxvt_ptytty_proxy ();
473
474	bool get ();
475	void login (int cmd_pid, bool login_shell, const char *hostname);
476	};
477
478	bool
479	rxvt_ptytty_proxy::get ()
480	{
481	command cmd;
482
483	cmd.type = command::get;
484
485	write (sock_fd, &cmd, sizeof (cmd));
486
487	if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
488	rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
489
490	if (!id)
491	return false;
492
493	if ((pty = rxvt_recv_fd (sock_fd)) < 0
494	\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
495	rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
496
497	return true;
498	}
499
500	void
501	rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
502	{
503	command cmd;
504
505	cmd.type = command::login;
506	cmd.id = id;
507	cmd.cmd_pid = cmd_pid;
508	cmd.login_shell = login_shell;
509	strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
510
511	write (sock_fd, &cmd, sizeof (cmd));
512	}
513
514	rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
515	{
516	command cmd;
517
518	cmd.type = command::destroy;
519	cmd.id = id;
520
521	write (sock_fd, &cmd, sizeof (cmd));
522	}
523
524	static
525	void serve ()
526	{
527	command cmd;
528	vector<rxvt_ptytty *> ptys;
529
530	while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
531	{
532	if (cmd.type == command::get)
533	{
534	// -> id ptyfd ttyfd
535	cmd.id = new rxvt_ptytty_unix;
536
537	if (cmd.id->get ())
538	{
539	write (sock_fd, &cmd.id, sizeof (cmd.id));
540	ptys.push_back (cmd.id);
541
542	rxvt_send_fd (sock_fd, cmd.id->pty);
543	rxvt_send_fd (sock_fd, cmd.id->tty);
544	}
545	else
546	{
547	delete cmd.id;
548	cmd.id = 0;
549	write (sock_fd, &cmd.id, sizeof (cmd.id));
550	}
551	}
552	else if (cmd.type == command::login)
553	{
554	#if UTMP_SUPPORT
555	if (find (ptys.begin (), ptys.end (), cmd.id))
556	{
557	cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
558	cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
559	}
560	#endif
561	}
562	else if (cmd.type == command::destroy)
563	{
564	rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
565
566	if (pty)
567	{
568	delete *pty;
569	ptys.erase (pty);
570	}
571	}
572	else
573	break;
574	}
575
576	// destroy all ptys
577	for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
578	delete *i;
579	}
580
581	void rxvt_ptytty_server ()
582	{
583	int sv[2];
584
585	if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
586	rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
587
588	pid = fork ();
589
590	if (pid < 0)
591	rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
592
593	if (pid)
594	{
595	// client, urxvt
596	sock_fd = sv[0];
597	close (sv[1]);
598	fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
599	}
600	else
601	{
602	// server, pty-helper
603	sock_fd = sv[1];
604
605	for (int fd = 0; fd < 1023; fd++)
606	if (fd != sock_fd)
607	close (fd);
608
609	serve ();
610	_exit (EXIT_SUCCESS);
611	}
612	}
613
614	#endif
615
616	// a "factory" g
617	rxvt_ptytty *
618	rxvt_new_ptytty ()
619	{
620	#if PTYTTY_HELPER
621	if (pid > 0)
622	// use helper process
623	return new rxvt_ptytty_proxy;
624	else
625	#endif
626	return new rxvt_ptytty_unix;
627	}
628
629	/----------------------- end-of-file (C source) -----------------------/
630