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/*--------------------------------*-C-*---------------------------------* |
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* File: ptytty.C |
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*----------------------------------------------------------------------* |
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* |
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* All portions of code are copyright by their respective author/s. |
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* Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com> |
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* Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com> |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
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*---------------------------------------------------------------------*/ |
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|
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#include "../config.h" /* NECESSARY */ |
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|
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#include "fdpass.h" |
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#include "ptytty.h" |
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|
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#include <cstdlib> |
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#include <cstring> |
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|
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <unistd.h> |
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#include <fcntl.h> |
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|
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#ifdef HAVE_SYS_IOCTL_H |
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# include <sys/ioctl.h> |
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#endif |
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#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H) |
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# include <sys/stropts.h> /* for I_PUSH */ |
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#endif |
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#ifdef HAVE_ISASTREAM |
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# include <stropts.h> |
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#endif |
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#if defined(HAVE_PTY_H) |
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# include <pty.h> |
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#elif defined(HAVE_LIBUTIL_H) |
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# include <libutil.h> |
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#elif defined(HAVE_UTIL_H) |
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# include <util.h> |
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#endif |
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#ifdef TTY_GID_SUPPORT |
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#include <grp.h> |
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#endif |
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|
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#include <cstdio> |
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|
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///////////////////////////////////////////////////////////////////////////// |
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|
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/* ------------------------------------------------------------------------- * |
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* GET PSEUDO TELETYPE - MASTER AND SLAVE * |
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* ------------------------------------------------------------------------- */ |
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/* |
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* Returns pty file descriptor, or -1 on failure |
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* If successful, ttydev is set to the name of the slave device. |
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* fd_tty _may_ also be set to an open fd to the slave device |
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*/ |
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#if defined(UNIX98_PTY) |
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static int |
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get_pty (int *fd_tty, char **ttydev) |
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{ |
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int pfd; |
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|
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# if defined(HAVE_GETPT) |
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pfd = getpt(); |
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# elif defined(HAVE_POSIX_OPENPT) |
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pfd = posix_openpt (O_RDWR); |
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# else |
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pfd = open (CLONE_DEVICE, O_RDWR | O_NOCTTY, 0); |
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# endif |
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if (pfd >= 0) |
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{ |
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if (grantpt (pfd) == 0 /* change slave permissions */ |
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&& unlockpt (pfd) == 0) |
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{ /* slave now unlocked */ |
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*ttydev = strdup (ptsname (pfd)); /* get slave's name */ |
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return pfd; |
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} |
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|
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close (pfd); |
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} |
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|
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return -1; |
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} |
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#elif defined(HAVE_OPENPTY) |
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static int |
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get_pty (int *fd_tty, char **ttydev) |
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{ |
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int pfd; |
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int res; |
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char tty_name[32]; |
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|
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res = openpty (&pfd, fd_tty, tty_name, NULL, NULL); |
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if (res != -1) |
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{ |
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*ttydev = strdup (tty_name); |
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return pfd; |
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} |
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|
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return -1; |
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} |
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#elif defined(HAVE__GETPTY) |
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static int |
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get_pty (int *fd_tty, char **ttydev) |
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{ |
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int pfd; |
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|
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*ttydev = _getpty (&pfd, O_RDWR | O_NONBLOCK | O_NOCTTY, 0622, 0); |
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if (*ttydev != NULL) |
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return pfd; |
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|
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return -1; |
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} |
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#elif defined(HAVE_DEV_PTC) |
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static int |
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get_pty (int *fd_tty, char **ttydev) |
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{ |
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int pfd; |
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|
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if ((pfd = open ("/dev/ptc", O_RDWR | O_NOCTTY, 0)) >= 0) |
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{ |
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*ttydev = strdup (ttyname (pfd)); |
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return pfd; |
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} |
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|
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return -1; |
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} |
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#elif defined(HAVE_DEV_CLONE) |
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static int |
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get_pty (int *fd_tty, char **ttydev) |
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{ |
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int pfd; |
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|
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if ((pfd = open ("/dev/ptym/clone", O_RDWR | O_NOCTTY, 0)) >= 0) |
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{ |
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*ttydev = strdup (ptsname (pfd)); |
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return pfd; |
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} |
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|
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return -1; |
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} |
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#else |
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/* Based on the code in openssh/openbsd-compat/bsd-openpty.c */ |
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static int |
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get_pty (int *fd_tty, char **ttydev) |
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{ |
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int pfd; |
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int i; |
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char pty_name[32]; |
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char tty_name[32]; |
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const char *majors = "pqrstuvwxyzabcde"; |
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const char *minors = "0123456789abcdef"; |
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for (i = 0; i < 256; i++) |
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{ |
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snprintf(pty_name, 32, "/dev/pty%c%c", majors[i / 16], minors[i % 16]); |
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snprintf(tty_name, 32, "/dev/tty%c%c", majors[i / 16], minors[i % 16]); |
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if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) == -1) |
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{ |
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snprintf(pty_name, 32, "/dev/ptyp%d", i); |
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snprintf(tty_name, 32, "/dev/ttyp%d", i); |
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if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) == -1) |
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continue; |
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} |
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if (access (tty_name, R_OK | W_OK) == 0) |
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{ |
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*ttydev = strdup (tty_name); |
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return pfd; |
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} |
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|
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close (pfd); |
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} |
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} |
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#endif |
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|
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/*----------------------------------------------------------------------*/ |
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/* |
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* Returns tty file descriptor, or -1 on failure |
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*/ |
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static int |
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get_tty (char *ttydev) |
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{ |
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return open (ttydev, O_RDWR | O_NOCTTY, 0); |
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} |
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|
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/*----------------------------------------------------------------------*/ |
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/* |
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* Make our tty a controlling tty so that /dev/tty points to us |
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*/ |
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static int |
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control_tty (int fd_tty) |
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{ |
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setsid (); |
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|
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#if defined(HAVE_DEV_PTMX) && defined(I_PUSH) |
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/* |
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* Push STREAMS modules: |
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* ptem: pseudo-terminal hardware emulation module. |
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* ldterm: standard terminal line discipline. |
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* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module. |
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* |
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* After we push the STREAMS modules, the first open () on the slave side |
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* (i.e. the next section between the dashes giving us "tty opened OK") |
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* should make the "ptem" (or "ldterm" depending upon either which OS |
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* version or which set of manual pages you have) module give us a |
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* controlling terminal. We must already have close ()d the master side |
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* fd in this child process before we push STREAMS modules on because the |
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* documentation is really unclear about whether it is any close () on |
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* the master side or the last close () - i.e. a proper STREAMS dismantling |
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* close () - on the master side which causes a hang up to be sent |
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* through - Geoff Wing |
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*/ |
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# ifdef HAVE_ISASTREAM |
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if (isastream (fd_tty) == 1) |
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# endif |
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{ |
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ioctl (fd_tty, I_PUSH, "ptem"); |
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ioctl (fd_tty, I_PUSH, "ldterm"); |
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ioctl (fd_tty, I_PUSH, "ttcompat"); |
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} |
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#endif |
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|
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ioctl (fd_tty, TIOCSCTTY, NULL); |
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|
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int fd = open ("/dev/tty", O_WRONLY); |
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if (fd < 0) |
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return -1; /* fatal */ |
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|
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close (fd); |
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|
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return 0; |
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} |
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|
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void |
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ptytty::close_tty () |
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{ |
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if (tty < 0) |
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return; |
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|
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close (tty); |
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tty = -1; |
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} |
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|
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bool |
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ptytty::make_controlling_tty () |
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{ |
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return control_tty (tty) >= 0; |
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} |
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|
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void |
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ptytty::set_utf8_mode (bool on) |
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{ |
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#ifdef IUTF8 |
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if (pty < 0) |
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return; |
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|
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struct termios tio; |
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|
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if (tcgetattr (pty, &tio) != -1) |
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{ |
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tcflag_t new_cflag = tio.c_iflag; |
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|
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if (on) |
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new_cflag |= IUTF8; |
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else |
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new_cflag &= ~IUTF8; |
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|
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if (new_cflag != tio.c_iflag) |
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{ |
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tio.c_iflag = new_cflag; |
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tcsetattr (pty, TCSANOW, &tio); |
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} |
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} |
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#endif |
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} |
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|
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static struct ttyconf { |
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gid_t gid; |
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mode_t mode; |
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|
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ttyconf () |
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{ |
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#ifdef TTY_GID_SUPPORT |
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struct group *gr = getgrnam ("tty"); |
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|
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if (gr) |
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{ /* change group ownership of tty to "tty" */ |
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mode = S_IRUSR | S_IWUSR | S_IWGRP; |
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gid = gr->gr_gid; |
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} |
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else |
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#endif /* TTY_GID_SUPPORT */ |
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{ |
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mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH; |
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gid = 0; |
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} |
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} |
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} ttyconf; |
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|
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ptytty_unix::ptytty_unix () |
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{ |
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name = 0; |
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#if UTMP_SUPPORT |
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cmd_pid = 0; |
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#endif |
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} |
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|
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ptytty_unix::~ptytty_unix () |
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{ |
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#if UTMP_SUPPORT |
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logout (); |
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#endif |
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put (); |
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} |
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|
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void |
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ptytty_unix::put () |
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{ |
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chmod (name, RESTORE_TTY_MODE); |
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chown (name, 0, ttyconf.gid); |
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|
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close_tty (); |
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|
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if (pty >= 0) |
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close (pty); |
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|
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free (name); |
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|
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pty = tty = -1; |
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name = 0; |
| 341 |
} |
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|
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bool |
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ptytty_unix::get () |
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{ |
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/* get master (pty) */ |
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if ((pty = get_pty (&tty, &name)) < 0) |
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return false; |
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|
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fcntl (pty, F_SETFL, O_NONBLOCK); |
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|
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/* get slave (tty) */ |
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if (tty < 0) |
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{ |
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#ifndef NO_SETOWNER_TTYDEV |
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chown (name, getuid (), ttyconf.gid); /* fail silently */ |
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chmod (name, ttyconf.mode); |
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# ifdef HAVE_REVOKE |
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revoke (name); |
| 360 |
# endif |
| 361 |
#endif |
| 362 |
|
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if ((tty = get_tty (name)) < 0) |
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{ |
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put (); |
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return false; |
| 367 |
} |
| 368 |
} |
| 369 |
|
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return true; |
| 371 |
} |
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|
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#if PTYTTY_HELPER |
| 374 |
|
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static int sock_fd; |
| 376 |
static int pid; |
| 377 |
|
| 378 |
struct command |
| 379 |
{ |
| 380 |
enum { get, login, destroy } type; |
| 381 |
|
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ptytty *id; |
| 383 |
|
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bool login_shell; |
| 385 |
int cmd_pid; |
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char hostname[512]; // arbitrary, but should be plenty |
| 387 |
}; |
| 388 |
|
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struct ptytty_proxy : ptytty |
| 390 |
{ |
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ptytty *id; |
| 392 |
|
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ptytty_proxy () |
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: id(0) |
| 395 |
{ |
| 396 |
} |
| 397 |
|
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~ptytty_proxy (); |
| 399 |
|
| 400 |
bool get (); |
| 401 |
void login (int cmd_pid, bool login_shell, const char *hostname); |
| 402 |
}; |
| 403 |
|
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bool |
| 405 |
ptytty_proxy::get () |
| 406 |
{ |
| 407 |
command cmd; |
| 408 |
|
| 409 |
cmd.type = command::get; |
| 410 |
|
| 411 |
write (sock_fd, &cmd, sizeof (cmd)); |
| 412 |
|
| 413 |
if (read (sock_fd, &id, sizeof (id)) != sizeof (id)) |
| 414 |
fatal ("protocol error while creating pty using helper process, aborting.\n"); |
| 415 |
|
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if (!id) |
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return false; |
| 418 |
|
| 419 |
if ((pty = ptytty_recv_fd (sock_fd)) < 0 |
| 420 |
|| (tty = ptytty_recv_fd (sock_fd)) < 0) |
| 421 |
fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n"); |
| 422 |
|
| 423 |
return true; |
| 424 |
} |
| 425 |
|
| 426 |
void |
| 427 |
ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname) |
| 428 |
{ |
| 429 |
command cmd; |
| 430 |
|
| 431 |
cmd.type = command::login; |
| 432 |
cmd.id = id; |
| 433 |
cmd.cmd_pid = cmd_pid; |
| 434 |
cmd.login_shell = login_shell; |
| 435 |
strncpy (cmd.hostname, hostname, sizeof (cmd.hostname)); |
| 436 |
|
| 437 |
write (sock_fd, &cmd, sizeof (cmd)); |
| 438 |
} |
| 439 |
|
| 440 |
ptytty_proxy::~ptytty_proxy () |
| 441 |
{ |
| 442 |
if (id) |
| 443 |
{ |
| 444 |
command cmd; |
| 445 |
|
| 446 |
cmd.type = command::destroy; |
| 447 |
cmd.id = id; |
| 448 |
|
| 449 |
write (sock_fd, &cmd, sizeof (cmd)); |
| 450 |
} |
| 451 |
} |
| 452 |
|
| 453 |
static |
| 454 |
void serve () |
| 455 |
{ |
| 456 |
command cmd; |
| 457 |
vector<ptytty *> ptys; |
| 458 |
|
| 459 |
while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command)) |
| 460 |
{ |
| 461 |
if (cmd.type == command::get) |
| 462 |
{ |
| 463 |
// -> id ptyfd ttyfd |
| 464 |
cmd.id = new ptytty_unix; |
| 465 |
|
| 466 |
if (cmd.id->get ()) |
| 467 |
{ |
| 468 |
write (sock_fd, &cmd.id, sizeof (cmd.id)); |
| 469 |
ptys.push_back (cmd.id); |
| 470 |
|
| 471 |
ptytty_send_fd (sock_fd, cmd.id->pty); |
| 472 |
ptytty_send_fd (sock_fd, cmd.id->tty); |
| 473 |
} |
| 474 |
else |
| 475 |
{ |
| 476 |
delete cmd.id; |
| 477 |
cmd.id = 0; |
| 478 |
write (sock_fd, &cmd.id, sizeof (cmd.id)); |
| 479 |
} |
| 480 |
} |
| 481 |
else if (cmd.type == command::login) |
| 482 |
{ |
| 483 |
#if UTMP_SUPPORT |
| 484 |
if (find (ptys.begin (), ptys.end (), cmd.id)) |
| 485 |
{ |
| 486 |
cmd.hostname[sizeof (cmd.hostname) - 1] = 0; |
| 487 |
cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname); |
| 488 |
} |
| 489 |
#endif |
| 490 |
} |
| 491 |
else if (cmd.type == command::destroy) |
| 492 |
{ |
| 493 |
ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id); |
| 494 |
|
| 495 |
if (pty) |
| 496 |
{ |
| 497 |
delete *pty; |
| 498 |
ptys.erase (pty); |
| 499 |
} |
| 500 |
} |
| 501 |
else |
| 502 |
break; |
| 503 |
} |
| 504 |
|
| 505 |
// destroy all ptys |
| 506 |
for (ptytty **i = ptys.end (); i-- > ptys.begin (); ) |
| 507 |
delete *i; |
| 508 |
} |
| 509 |
|
| 510 |
void ptytty_server () |
| 511 |
{ |
| 512 |
int sv[2]; |
| 513 |
|
| 514 |
if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv)) |
| 515 |
fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n"); |
| 516 |
|
| 517 |
pid = fork (); |
| 518 |
|
| 519 |
if (pid < 0) |
| 520 |
fatal ("could not create pty/sessiondb helper process, aborting.\n"); |
| 521 |
|
| 522 |
if (pid) |
| 523 |
{ |
| 524 |
// client, process |
| 525 |
sock_fd = sv[0]; |
| 526 |
close (sv[1]); |
| 527 |
fcntl (sock_fd, F_SETFD, FD_CLOEXEC); |
| 528 |
} |
| 529 |
else |
| 530 |
{ |
| 531 |
// server, pty-helper |
| 532 |
sock_fd = sv[1]; |
| 533 |
|
| 534 |
for (int fd = 0; fd < 1023; fd++) |
| 535 |
if (fd != sock_fd) |
| 536 |
close (fd); |
| 537 |
|
| 538 |
serve (); |
| 539 |
_exit (EXIT_SUCCESS); |
| 540 |
} |
| 541 |
} |
| 542 |
|
| 543 |
#endif |
| 544 |
|
| 545 |
// a "factory" *g* |
| 546 |
ptytty * |
| 547 |
new_ptytty () |
| 548 |
{ |
| 549 |
#if PTYTTY_HELPER |
| 550 |
if (pid > 0) |
| 551 |
// use helper process |
| 552 |
return new ptytty_proxy; |
| 553 |
else |
| 554 |
#endif |
| 555 |
return new ptytty_unix; |
| 556 |
} |
| 557 |
|
| 558 |
/*----------------------- end-of-file (C source) -----------------------*/ |
| 559 |
|
