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 <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>

#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
 */
#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:	1.2
Committed:	Sat Jan 21 22:01:36 2006 UTC (18 years, 5 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.1:	+342 -267 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 <cstdlib>
27	#include <cstring>
28
29	#include <sys/types.h>
30	#include <sys/socket.h>
31	#include <unistd.h>
32	#include <fcntl.h>
33
34	#ifdef HAVE_SYS_IOCTL_H
35	# include <sys/ioctl.h>
36	#endif
37	#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H)
38	# include <sys/stropts.h> /* for I_PUSH */
39	#endif
40	#ifdef HAVE_ISASTREAM
41	# include <stropts.h>
42	#endif
43	#if defined(HAVE_PTY_H)
44	# include <pty.h>
45	#elif defined(HAVE_LIBUTIL_H)
46	# include <libutil.h>
47	#elif defined(HAVE_UTIL_H)
48	# include <util.h>
49	#endif
50	#ifdef TTY_GID_SUPPORT
51	#include <grp.h>
52	#endif
53
54	#include <cstdio>
55
56	#include "rxvtutil.h"
57	#include "fdpass.h"
58	#include "ptytty.h"
59
60	/////////////////////////////////////////////////////////////////////////////
61
62	/* ------------------------------------------------------------------------- *
63	* GET PSEUDO TELETYPE - MASTER AND SLAVE *
64	* ------------------------------------------------------------------------- */
65	/*
66	* Returns pty file descriptor, or -1 on failure
67	* If successful, ttydev is set to the name of the slave device.
68	* fd_tty _may_ also be set to an open fd to the slave device
69	*/
70	#if defined(UNIX98_PTY)
71	static int
72	get_pty (int fd_tty, char *ttydev)
73	{
74	int pfd;
75
76	# if defined(HAVE_GETPT)
77	pfd = getpt();
78	# elif defined(HAVE_POSIX_OPENPT)
79	pfd = posix_openpt (O_RDWR);
80	# else
81	pfd = open (CLONE_DEVICE, 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
95	return -1;
96	}
97	#elif defined(HAVE_OPENPTY)
98	static int
99	get_pty (int fd_tty, char *ttydev)
100	{
101	int pfd;
102	int res;
103	char tty_name[32];
104
105	res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
106	if (res != -1)
107	{
108	*ttydev = strdup (tty_name);
109	return pfd;
110	}
111
112	return -1;
113	}
114	#elif defined(HAVE__GETPTY)
115	static int
116	get_pty (int fd_tty, char *ttydev)
117	{
118	int pfd;
119
120	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
121	if (*ttydev != NULL)
122	return pfd;
123
124	return -1;
125	}
126	#elif defined(HAVE_DEV_PTC)
127	static int
128	get_pty (int fd_tty, char *ttydev)
129	{
130	int pfd;
131
132	if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
133	{
134	*ttydev = strdup (ttyname (pfd));
135	return pfd;
136	}
137
138	return -1;
139	}
140	#elif defined(HAVE_DEV_CLONE)
141	static int
142	get_pty (int fd_tty, char *ttydev)
143	{
144	int pfd;
145
146	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
147	{
148	*ttydev = strdup (ptsname (pfd));
149	return pfd;
150	}
151
152	return -1;
153	}
154	#else
155	/* Based on the code in openssh/openbsd-compat/bsd-openpty.c */
156	static int
157	get_pty (int fd_tty, char *ttydev)
158	{
159	int pfd;
160	int i;
161	char pty_name[32];
162	char tty_name[32];
163	const char *majors = "pqrstuvwxyzabcde";
164	const char *minors = "0123456789abcdef";
165	for (i = 0; i < 256; i++)
166	{
167	snprintf(pty_name, 32, "/dev/pty%c%c", majors[i / 16], minors[i % 16]);
168	snprintf(tty_name, 32, "/dev/tty%c%c", majors[i / 16], minors[i % 16]);
169	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) == -1)
170	{
171	snprintf(pty_name, 32, "/dev/ptyp%d", i);
172	snprintf(tty_name, 32, "/dev/ttyp%d", i);
173	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) == -1)
174	continue;
175	}
176	if (access (tty_name, R_OK \| W_OK) == 0)
177	{
178	*ttydev = strdup (tty_name);
179	return pfd;
180	}
181
182	close (pfd);
183	}
184	}
185	#endif
186
187	/----------------------------------------------------------------------/
188	/*
189	* Returns tty file descriptor, or -1 on failure
190	*/
191	static int
192	get_tty (char *ttydev)
193	{
194	return open (ttydev, O_RDWR \| O_NOCTTY, 0);
195	}
196
197	/----------------------------------------------------------------------/
198	/*
199	* Make our tty a controlling tty so that /dev/tty points to us
200	*/
201	static int
202	control_tty (int fd_tty)
203	{
204	setsid ();
205
206	#if defined(HAVE_DEV_PTMX) && defined(I_PUSH)
207	/*
208	* Push STREAMS modules:
209	* ptem: pseudo-terminal hardware emulation module.
210	* ldterm: standard terminal line discipline.
211	* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
212	*
213	* After we push the STREAMS modules, the first open () on the slave side
214	* (i.e. the next section between the dashes giving us "tty opened OK")
215	* should make the "ptem" (or "ldterm" depending upon either which OS
216	* version or which set of manual pages you have) module give us a
217	* controlling terminal. We must already have close ()d the master side
218	* fd in this child process before we push STREAMS modules on because the
219	* documentation is really unclear about whether it is any close () on
220	* the master side or the last close () - i.e. a proper STREAMS dismantling
221	* close () - on the master side which causes a hang up to be sent
222	* through - Geoff Wing
223	*/
224	# ifdef HAVE_ISASTREAM
225	if (isastream (fd_tty) == 1)
226	# endif
227	{
228	ioctl (fd_tty, I_PUSH, "ptem");
229	ioctl (fd_tty, I_PUSH, "ldterm");
230	ioctl (fd_tty, I_PUSH, "ttcompat");
231	}
232	#endif
233
234	ioctl (fd_tty, TIOCSCTTY, NULL);
235
236	int fd = open ("/dev/tty", O_WRONLY);
237	if (fd < 0)
238	return -1; /* fatal */
239
240	close (fd);
241
242	return 0;
243	}
244
245	void
246	rxvt_ptytty::close_tty ()
247	{
248	if (tty < 0)
249	return;
250
251	close (tty);
252	tty = -1;
253	}
254
255	bool
256	rxvt_ptytty::make_controlling_tty ()
257	{
258	return control_tty (tty) >= 0;
259	}
260
261	void
262	rxvt_ptytty::set_utf8_mode (bool on)
263	{
264	#ifdef IUTF8
265	if (pty < 0)
266	return;
267
268	struct termios tio;
269
270	if (tcgetattr (pty, &tio) != -1)
271	{
272	tcflag_t new_cflag = tio.c_iflag;
273
274	if (on)
275	new_cflag \|= IUTF8;
276	else
277	new_cflag &= ~IUTF8;
278
279	if (new_cflag != tio.c_iflag)
280	{
281	tio.c_iflag = new_cflag;
282	tcsetattr (pty, TCSANOW, &tio);
283	}
284	}
285	#endif
286	}
287
288	static struct ttyconf {
289	gid_t gid;
290	mode_t mode;
291
292	ttyconf ()
293	{
294	#ifdef TTY_GID_SUPPORT
295	struct group *gr = getgrnam ("tty");
296
297	if (gr)
298	{ /* change group ownership of tty to "tty" */
299	mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
300	gid = gr->gr_gid;
301	}
302	else
303	#endif /* TTY_GID_SUPPORT */
304	{
305	mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
306	gid = 0;
307	}
308	}
309	} ttyconf;
310
311	rxvt_ptytty_unix::rxvt_ptytty_unix ()
312	{
313	name = 0;
314	#if UTMP_SUPPORT
315	cmd_pid = 0;
316	#endif
317	}
318
319	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
320	{
321	#if UTMP_SUPPORT
322	logout ();
323	#endif
324	put ();
325	}
326
327	void
328	rxvt_ptytty_unix::put ()
329	{
330	chmod (name, RESTORE_TTY_MODE);
331	chown (name, 0, ttyconf.gid);
332
333	close_tty ();
334
335	if (pty >= 0)
336	close (pty);
337
338	free (name);
339
340	pty = tty = -1;
341	name = 0;
342	}
343
344	bool
345	rxvt_ptytty_unix::get ()
346	{
347	/* get master (pty) */
348	if ((pty = get_pty (&tty, &name)) < 0)
349	return false;
350
351	fcntl (pty, F_SETFL, O_NONBLOCK);
352
353	/* get slave (tty) */
354	if (tty < 0)
355	{
356	#ifndef NO_SETOWNER_TTYDEV
357	chown (name, getuid (), ttyconf.gid); /* fail silently */
358	chmod (name, ttyconf.mode);
359	# ifdef HAVE_REVOKE
360	revoke (name);
361	# endif
362	#endif
363
364	if ((tty = get_tty (name)) < 0)
365	{
366	put ();
367	return false;
368	}
369	}
370
371	return true;
372	}
373
374	#if PTYTTY_HELPER
375
376	static int sock_fd;
377	static int pid;
378
379	struct command
380	{
381	enum { get, login, destroy } type;
382
383	rxvt_ptytty *id;
384
385	bool login_shell;
386	int cmd_pid;
387	char hostname[512]; // arbitrary, but should be plenty
388	};
389
390	struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
391	{
392	rxvt_ptytty *id;
393
394	~rxvt_ptytty_proxy ();
395
396	bool get ();
397	void login (int cmd_pid, bool login_shell, const char *hostname);
398	};
399
400	bool
401	rxvt_ptytty_proxy::get ()
402	{
403	command cmd;
404
405	cmd.type = command::get;
406
407	write (sock_fd, &cmd, sizeof (cmd));
408
409	if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
410	rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
411
412	if (!id)
413	return false;
414
415	if ((pty = rxvt_recv_fd (sock_fd)) < 0
416	\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
417	rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
418
419	return true;
420	}
421
422	void
423	rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
424	{
425	command cmd;
426
427	cmd.type = command::login;
428	cmd.id = id;
429	cmd.cmd_pid = cmd_pid;
430	cmd.login_shell = login_shell;
431	strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
432
433	write (sock_fd, &cmd, sizeof (cmd));
434	}
435
436	rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
437	{
438	command cmd;
439
440	cmd.type = command::destroy;
441	cmd.id = id;
442
443	write (sock_fd, &cmd, sizeof (cmd));
444	}
445
446	static
447	void serve ()
448	{
449	command cmd;
450	vector<rxvt_ptytty *> ptys;
451
452	while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
453	{
454	if (cmd.type == command::get)
455	{
456	// -> id ptyfd ttyfd
457	cmd.id = new rxvt_ptytty_unix;
458
459	if (cmd.id->get ())
460	{
461	write (sock_fd, &cmd.id, sizeof (cmd.id));
462	ptys.push_back (cmd.id);
463
464	rxvt_send_fd (sock_fd, cmd.id->pty);
465	rxvt_send_fd (sock_fd, cmd.id->tty);
466	}
467	else
468	{
469	delete cmd.id;
470	cmd.id = 0;
471	write (sock_fd, &cmd.id, sizeof (cmd.id));
472	}
473	}
474	else if (cmd.type == command::login)
475	{
476	#if UTMP_SUPPORT
477	if (find (ptys.begin (), ptys.end (), cmd.id))
478	{
479	cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
480	cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
481	}
482	#endif
483	}
484	else if (cmd.type == command::destroy)
485	{
486	rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
487
488	if (pty)
489	{
490	delete *pty;
491	ptys.erase (pty);
492	}
493	}
494	else
495	break;
496	}
497
498	// destroy all ptys
499	for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
500	delete *i;
501	}
502
503	void rxvt_ptytty_server ()
504	{
505	int sv[2];
506
507	if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
508	rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
509
510	pid = fork ();
511
512	if (pid < 0)
513	rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
514
515	if (pid)
516	{
517	// client, urxvt
518	sock_fd = sv[0];
519	close (sv[1]);
520	fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
521	}
522	else
523	{
524	// server, pty-helper
525	sock_fd = sv[1];
526
527	for (int fd = 0; fd < 1023; fd++)
528	if (fd != sock_fd)
529	close (fd);
530
531	serve ();
532	_exit (EXIT_SUCCESS);
533	}
534	}
535
536	#endif
537
538	// a "factory" g
539	rxvt_ptytty *
540	rxvt_new_ptytty ()
541	{
542	#if PTYTTY_HELPER
543	if (pid > 0)
544	// use helper process
545	return new rxvt_ptytty_proxy;
546	else
547	#endif
548	return new rxvt_ptytty_unix;
549	}
550
551	/----------------------- end-of-file (C source) -----------------------/
552