libptytty/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 "fdpass.h"
#include "ptytty.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(HAVE_DEV_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
#ifdef TTY_GID_SUPPORT
#include <grp.h>
#endif

#include <cstdio>

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

/* ------------------------------------------------------------------------- *
 *                  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
 */
#if defined(UNIX98_PTY)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

# if defined(HAVE_GETPT)
  pfd = getpt();
# elif defined(HAVE_POSIX_OPENPT)
  pfd = posix_openpt (O_RDWR);
# else
  pfd = open (CLONE_DEVICE, 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);
    }

  return -1;
}
#elif defined(HAVE_OPENPTY)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;
  int res;
  char tty_name[32];
  
  res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
  if (res != -1)
    {
      *ttydev = strdup (tty_name);
      return pfd;
    }

  return -1;
}
#elif defined(HAVE__GETPTY)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

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

  return -1;
}
#elif defined(HAVE_DEV_PTC)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

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

  return -1;
}
#elif defined(HAVE_DEV_CLONE)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

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

  return -1;
}
#else
/* Based on the code in openssh/openbsd-compat/bsd-openpty.c */
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;
  int i;
  char pty_name[32];
  char tty_name[32];
  const char *majors = "pqrstuvwxyzabcde";
  const char *minors = "0123456789abcdef";
  for (i = 0; i < 256; i++)
    {
      snprintf(pty_name, 32, "/dev/pty%c%c", majors[i / 16], minors[i % 16]);
      snprintf(tty_name, 32, "/dev/tty%c%c", majors[i / 16], minors[i % 16]);
      if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) == -1)
        {
          snprintf(pty_name, 32, "/dev/ptyp%d", i);
          snprintf(tty_name, 32, "/dev/ttyp%d", i);
          if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) == -1)
            continue;
        }
      if (access (tty_name, R_OK | W_OK) == 0)
        {
          *ttydev = strdup (tty_name);
          return pfd;
        }

      close (pfd);
    }
}
#endif

/*----------------------------------------------------------------------*/
/*
 * 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(HAVE_DEV_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 ()
{
  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:	1.3
Committed:	Sat Jan 21 22:06:16 2006 UTC (18 years, 5 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.2:	+3 -4 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
26	#include "fdpass.h"
27	#include "ptytty.h"
28
29	#include <cstdlib>
30	#include <cstring>
31
32	#include <sys/types.h>
33	#include <sys/socket.h>
34	#include <unistd.h>
35	#include <fcntl.h>
36
37	#ifdef HAVE_SYS_IOCTL_H
38	# include <sys/ioctl.h>
39	#endif
40	#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H)
41	# include <sys/stropts.h> /* for I_PUSH */
42	#endif
43	#ifdef HAVE_ISASTREAM
44	# include <stropts.h>
45	#endif
46	#if defined(HAVE_PTY_H)
47	# include <pty.h>
48	#elif defined(HAVE_LIBUTIL_H)
49	# include <libutil.h>
50	#elif defined(HAVE_UTIL_H)
51	# include <util.h>
52	#endif
53	#ifdef TTY_GID_SUPPORT
54	#include <grp.h>
55	#endif
56
57	#include <cstdio>
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	#if defined(UNIX98_PTY)
70	static int
71	get_pty (int fd_tty, char *ttydev)
72	{
73	int pfd;
74
75	# if defined(HAVE_GETPT)
76	pfd = getpt();
77	# elif defined(HAVE_POSIX_OPENPT)
78	pfd = posix_openpt (O_RDWR);
79	# else
80	pfd = open (CLONE_DEVICE, O_RDWR \| O_NOCTTY, 0);
81	# endif
82	if (pfd >= 0)
83	{
84	if (grantpt (pfd) == 0 /* change slave permissions */
85	&& unlockpt (pfd) == 0)
86	{ /* slave now unlocked */
87	ttydev = strdup (ptsname (pfd)); / get slave's name */
88	return pfd;
89	}
90
91	close (pfd);
92	}
93
94	return -1;
95	}
96	#elif defined(HAVE_OPENPTY)
97	static int
98	get_pty (int fd_tty, char *ttydev)
99	{
100	int pfd;
101	int res;
102	char tty_name[32];
103
104	res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
105	if (res != -1)
106	{
107	*ttydev = strdup (tty_name);
108	return pfd;
109	}
110
111	return -1;
112	}
113	#elif defined(HAVE__GETPTY)
114	static int
115	get_pty (int fd_tty, char *ttydev)
116	{
117	int pfd;
118
119	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
120	if (*ttydev != NULL)
121	return pfd;
122
123	return -1;
124	}
125	#elif defined(HAVE_DEV_PTC)
126	static int
127	get_pty (int fd_tty, char *ttydev)
128	{
129	int pfd;
130
131	if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
132	{
133	*ttydev = strdup (ttyname (pfd));
134	return pfd;
135	}
136
137	return -1;
138	}
139	#elif defined(HAVE_DEV_CLONE)
140	static int
141	get_pty (int fd_tty, char *ttydev)
142	{
143	int pfd;
144
145	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
146	{
147	*ttydev = strdup (ptsname (pfd));
148	return pfd;
149	}
150
151	return -1;
152	}
153	#else
154	/* Based on the code in openssh/openbsd-compat/bsd-openpty.c */
155	static int
156	get_pty (int fd_tty, char *ttydev)
157	{
158	int pfd;
159	int i;
160	char pty_name[32];
161	char tty_name[32];
162	const char *majors = "pqrstuvwxyzabcde";
163	const char *minors = "0123456789abcdef";
164	for (i = 0; i < 256; i++)
165	{
166	snprintf(pty_name, 32, "/dev/pty%c%c", majors[i / 16], minors[i % 16]);
167	snprintf(tty_name, 32, "/dev/tty%c%c", majors[i / 16], minors[i % 16]);
168	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) == -1)
169	{
170	snprintf(pty_name, 32, "/dev/ptyp%d", i);
171	snprintf(tty_name, 32, "/dev/ttyp%d", i);
172	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) == -1)
173	continue;
174	}
175	if (access (tty_name, R_OK \| W_OK) == 0)
176	{
177	*ttydev = strdup (tty_name);
178	return pfd;
179	}
180
181	close (pfd);
182	}
183	}
184	#endif
185
186	/----------------------------------------------------------------------/
187	/*
188	* Returns tty file descriptor, or -1 on failure
189	*/
190	static int
191	get_tty (char *ttydev)
192	{
193	return open (ttydev, O_RDWR \| O_NOCTTY, 0);
194	}
195
196	/----------------------------------------------------------------------/
197	/*
198	* Make our tty a controlling tty so that /dev/tty points to us
199	*/
200	static int
201	control_tty (int fd_tty)
202	{
203	setsid ();
204
205	#if defined(HAVE_DEV_PTMX) && defined(I_PUSH)
206	/*
207	* Push STREAMS modules:
208	* ptem: pseudo-terminal hardware emulation module.
209	* ldterm: standard terminal line discipline.
210	* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
211	*
212	* After we push the STREAMS modules, the first open () on the slave side
213	* (i.e. the next section between the dashes giving us "tty opened OK")
214	* should make the "ptem" (or "ldterm" depending upon either which OS
215	* version or which set of manual pages you have) module give us a
216	* controlling terminal. We must already have close ()d the master side
217	* fd in this child process before we push STREAMS modules on because the
218	* documentation is really unclear about whether it is any close () on
219	* the master side or the last close () - i.e. a proper STREAMS dismantling
220	* close () - on the master side which causes a hang up to be sent
221	* through - Geoff Wing
222	*/
223	# ifdef HAVE_ISASTREAM
224	if (isastream (fd_tty) == 1)
225	# endif
226	{
227	ioctl (fd_tty, I_PUSH, "ptem");
228	ioctl (fd_tty, I_PUSH, "ldterm");
229	ioctl (fd_tty, I_PUSH, "ttcompat");
230	}
231	#endif
232
233	ioctl (fd_tty, TIOCSCTTY, NULL);
234
235	int fd = open ("/dev/tty", O_WRONLY);
236	if (fd < 0)
237	return -1; /* fatal */
238
239	close (fd);
240
241	return 0;
242	}
243
244	void
245	rxvt_ptytty::close_tty ()
246	{
247	if (tty < 0)
248	return;
249
250	close (tty);
251	tty = -1;
252	}
253
254	bool
255	rxvt_ptytty::make_controlling_tty ()
256	{
257	return control_tty (tty) >= 0;
258	}
259
260	void
261	rxvt_ptytty::set_utf8_mode (bool on)
262	{
263	#ifdef IUTF8
264	if (pty < 0)
265	return;
266
267	struct termios tio;
268
269	if (tcgetattr (pty, &tio) != -1)
270	{
271	tcflag_t new_cflag = tio.c_iflag;
272
273	if (on)
274	new_cflag \|= IUTF8;
275	else
276	new_cflag &= ~IUTF8;
277
278	if (new_cflag != tio.c_iflag)
279	{
280	tio.c_iflag = new_cflag;
281	tcsetattr (pty, TCSANOW, &tio);
282	}
283	}
284	#endif
285	}
286
287	static struct ttyconf {
288	gid_t gid;
289	mode_t mode;
290
291	ttyconf ()
292	{
293	#ifdef TTY_GID_SUPPORT
294	struct group *gr = getgrnam ("tty");
295
296	if (gr)
297	{ /* change group ownership of tty to "tty" */
298	mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
299	gid = gr->gr_gid;
300	}
301	else
302	#endif /* TTY_GID_SUPPORT */
303	{
304	mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
305	gid = 0;
306	}
307	}
308	} ttyconf;
309
310	rxvt_ptytty_unix::rxvt_ptytty_unix ()
311	{
312	name = 0;
313	#if UTMP_SUPPORT
314	cmd_pid = 0;
315	#endif
316	}
317
318	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
319	{
320	#if UTMP_SUPPORT
321	logout ();
322	#endif
323	put ();
324	}
325
326	void
327	rxvt_ptytty_unix::put ()
328	{
329	chmod (name, RESTORE_TTY_MODE);
330	chown (name, 0, ttyconf.gid);
331
332	close_tty ();
333
334	if (pty >= 0)
335	close (pty);
336
337	free (name);
338
339	pty = tty = -1;
340	name = 0;
341	}
342
343	bool
344	rxvt_ptytty_unix::get ()
345	{
346	/* get master (pty) */
347	if ((pty = get_pty (&tty, &name)) < 0)
348	return false;
349
350	fcntl (pty, F_SETFL, O_NONBLOCK);
351
352	/* get slave (tty) */
353	if (tty < 0)
354	{
355	#ifndef NO_SETOWNER_TTYDEV
356	chown (name, getuid (), ttyconf.gid); /* fail silently */
357	chmod (name, ttyconf.mode);
358	# ifdef HAVE_REVOKE
359	revoke (name);
360	# endif
361	#endif
362
363	if ((tty = get_tty (name)) < 0)
364	{
365	put ();
366	return false;
367	}
368	}
369
370	return true;
371	}
372
373	#if PTYTTY_HELPER
374
375	static int sock_fd;
376	static int pid;
377
378	struct command
379	{
380	enum { get, login, destroy } type;
381
382	rxvt_ptytty *id;
383
384	bool login_shell;
385	int cmd_pid;
386	char hostname[512]; // arbitrary, but should be plenty
387	};
388
389	struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
390	{
391	rxvt_ptytty *id;
392
393	~rxvt_ptytty_proxy ();
394
395	bool get ();
396	void login (int cmd_pid, bool login_shell, const char *hostname);
397	};
398
399	bool
400	rxvt_ptytty_proxy::get ()
401	{
402	command cmd;
403
404	cmd.type = command::get;
405
406	write (sock_fd, &cmd, sizeof (cmd));
407
408	if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
409	rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
410
411	if (!id)
412	return false;
413
414	if ((pty = rxvt_recv_fd (sock_fd)) < 0
415	\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
416	rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
417
418	return true;
419	}
420
421	void
422	rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
423	{
424	command cmd;
425
426	cmd.type = command::login;
427	cmd.id = id;
428	cmd.cmd_pid = cmd_pid;
429	cmd.login_shell = login_shell;
430	strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
431
432	write (sock_fd, &cmd, sizeof (cmd));
433	}
434
435	rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
436	{
437	command cmd;
438
439	cmd.type = command::destroy;
440	cmd.id = id;
441
442	write (sock_fd, &cmd, sizeof (cmd));
443	}
444
445	static
446	void serve ()
447	{
448	command cmd;
449	vector<rxvt_ptytty *> ptys;
450
451	while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
452	{
453	if (cmd.type == command::get)
454	{
455	// -> id ptyfd ttyfd
456	cmd.id = new rxvt_ptytty_unix;
457
458	if (cmd.id->get ())
459	{
460	write (sock_fd, &cmd.id, sizeof (cmd.id));
461	ptys.push_back (cmd.id);
462
463	rxvt_send_fd (sock_fd, cmd.id->pty);
464	rxvt_send_fd (sock_fd, cmd.id->tty);
465	}
466	else
467	{
468	delete cmd.id;
469	cmd.id = 0;
470	write (sock_fd, &cmd.id, sizeof (cmd.id));
471	}
472	}
473	else if (cmd.type == command::login)
474	{
475	#if UTMP_SUPPORT
476	if (find (ptys.begin (), ptys.end (), cmd.id))
477	{
478	cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
479	cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
480	}
481	#endif
482	}
483	else if (cmd.type == command::destroy)
484	{
485	rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
486
487	if (pty)
488	{
489	delete *pty;
490	ptys.erase (pty);
491	}
492	}
493	else
494	break;
495	}
496
497	// destroy all ptys
498	for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
499	delete *i;
500	}
501
502	void rxvt_ptytty_server ()
503	{
504	int sv[2];
505
506	if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
507	rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
508
509	pid = fork ();
510
511	if (pid < 0)
512	rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
513
514	if (pid)
515	{
516	// client, urxvt
517	sock_fd = sv[0];
518	close (sv[1]);
519	fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
520	}
521	else
522	{
523	// server, pty-helper
524	sock_fd = sv[1];
525
526	for (int fd = 0; fd < 1023; fd++)
527	if (fd != sock_fd)
528	close (fd);
529
530	serve ();
531	_exit (EXIT_SUCCESS);
532	}
533	}
534
535	#endif
536
537	// a "factory" g
538	rxvt_ptytty *
539	rxvt_new_ptytty ()
540	{
541	#if PTYTTY_HELPER
542	if (pid > 0)
543	// use helper process
544	return new rxvt_ptytty_proxy;
545	else
546	#endif
547	return new rxvt_ptytty_unix;
548	}
549
550	/----------------------- end-of-file (C source) -----------------------/
551