2 Concurrent shell support for the Midnight Commander
4 Copyright (C) 1994, 1995, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
5 2005, 2006, 2007, 2011, 2013
6 The Free Software Foundation, Inc.
9 Slava Zanko <slavazanko@gmail.com>, 2013
11 This file is part of the Midnight Commander.
13 The Midnight Commander is free software: you can redistribute it
14 and/or modify it under the terms of the GNU General Public License as
15 published by the Free Software Foundation, either version 3 of the License,
16 or (at your option) any later version.
18 The Midnight Commander is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License for more details.
23 You should have received a copy of the GNU General Public License
24 along with this program. If not, see <http://www.gnu.org/licenses/>.
28 * \brief Source: concurrent shell support
44 #include <sys/types.h>
46 #ifdef HAVE_SYS_IOCTL_H
47 #include <sys/ioctl.h>
53 #include <stropts.h> /* For I_PUSH */
54 #endif /* HAVE_STROPTS_H */
56 #include "lib/global.h"
58 #include "lib/tty/tty.h" /* LINES */
59 #include "lib/tty/key.h" /* XCTRL */
60 #include "lib/vfs/vfs.h"
61 #include "lib/strutil.h"
62 #include "lib/mcconfig.h"
64 #include "lib/widget.h"
66 #include "filemanager/midnight.h" /* current_panel */
68 #include "consaver/cons.saver.h" /* handle_console() */
72 /*** global variables ****************************************************************************/
74 /* State of the subshell:
75 * INACTIVE: the default state; awaiting a command
76 * ACTIVE: remain in the shell until the user hits 'subshell_switch_key'
77 * RUNNING_COMMAND: return to MC when the current command finishes */
78 enum subshell_state_enum subshell_state
;
80 /* Holds the latest prompt captured from the subshell */
81 GString
*subshell_prompt
= NULL
;
83 /* Subshell: if set, then the prompt was not saved on CONSOLE_SAVE */
84 /* We need to paint it after CONSOLE_RESTORE, see: load_prompt */
85 gboolean update_subshell_prompt
= FALSE
;
87 /*** file scope macro definitions ****************************************************************/
90 #define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
94 #define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
98 #define STDIN_FILENO 0
101 #ifndef STDOUT_FILENO
102 #define STDOUT_FILENO 1
105 #ifndef STDERR_FILENO
106 #define STDERR_FILENO 2
109 /* Initial length of the buffer for the subshell's prompt */
110 #define INITIAL_PROMPT_SIZE 10
112 /* Used by the child process to indicate failure to start the subshell */
113 #define FORK_FAILURE 69 /* Arbitrary */
115 /* Length of the buffer for all I/O with the subshell */
116 #define PTY_BUFFER_SIZE BUF_SMALL /* Arbitrary; but keep it >= 80 */
118 /*** file scope type declarations ****************************************************************/
127 /* Subshell type (gleaned from the SHELL environment variable, if available) */
136 /*** file scope variables ************************************************************************/
138 /* tcsh closes all non-standard file descriptors, so we have to use a pipe */
139 static char tcsh_fifo
[128];
141 static int subshell_pty_slave
= -1;
143 /* The key for switching back to MC from the subshell */
145 static const char subshell_switch_key
= XCTRL ('o') & 255;
148 /* For reading/writing on the subshell's pty */
149 static char pty_buffer
[PTY_BUFFER_SIZE
] = "\0";
151 /* To pass CWD info from the subshell to MC */
152 static int subshell_pipe
[2];
154 /* The subshell's process ID */
155 static pid_t subshell_pid
= 1;
157 /* One extra char for final '\n' */
158 static char subshell_cwd
[MC_MAXPATHLEN
+ 1];
160 /* Flag to indicate whether the subshell is ready for next command */
161 static int subshell_ready
;
163 /* The following two flags can be changed by the SIGCHLD handler. This is */
164 /* OK, because the 'int' type is updated atomically on all known machines */
165 static volatile int subshell_alive
, subshell_stopped
;
167 /* We store the terminal's initial mode here so that we can configure
168 the pty similarly, and also so we can restore the real terminal to
169 sanity if we have to exit abruptly */
170 static struct termios shell_mode
;
172 /* This is a transparent mode for the terminal where MC is running on */
173 /* It is used when the shell is active, so that the control signals */
174 /* are delivered to the shell pty */
175 static struct termios raw_mode
;
177 /* --------------------------------------------------------------------------------------------- */
178 /*** file scope functions ************************************************************************/
179 /* --------------------------------------------------------------------------------------------- */
181 * Write all data, even if the write() call is interrupted.
185 write_all (int fd
, const void *buf
, size_t count
)
191 ret
= write (fd
, (const unsigned char *) buf
+ written
, count
);
196 if (mc_global
.tty
.winch_flag
!= 0)
197 tty_change_screen_size ();
202 return written
> 0 ? written
: ret
;
210 /* --------------------------------------------------------------------------------------------- */
212 * Prepare child process to running the shell and run it.
214 * Modifies the global variables (in the child process only):
221 init_subshell_child (const char *pty_name
)
223 char *init_file
= NULL
;
227 setsid (); /* Get a fresh terminal session */
229 /* Make sure that it has become our controlling terminal */
231 /* Redundant on Linux and probably most systems, but just in case: */
234 ioctl (subshell_pty_slave
, TIOCSCTTY
, 0);
237 /* Configure its terminal modes and window size */
239 /* Set up the pty with the same termios flags as our own tty */
240 if (tcsetattr (subshell_pty_slave
, TCSANOW
, &shell_mode
))
242 fprintf (stderr
, "Cannot set pty terminal modes: %s\r\n", unix_error_string (errno
));
243 my_exit (FORK_FAILURE
);
246 /* Set the pty's size (80x25 by default on Linux) according to the */
247 /* size of the real terminal as calculated by ncurses, if possible */
248 tty_resize (subshell_pty_slave
);
250 /* Set up the subshell's environment and init file name */
252 /* It simplifies things to change to our home directory here, */
253 /* and the user's startup file may do a 'cd' command anyway */
256 ret
= chdir (mc_config_get_home_dir ()); /* FIXME? What about when we re-run the subshell? */
260 /* Set MC_SID to prevent running one mc from another */
264 char sid_str
[BUF_SMALL
];
265 g_snprintf (sid_str
, sizeof (sid_str
), "MC_SID=%ld", (long) mc_sid
);
266 putenv (g_strdup (sid_str
));
269 switch (subshell_type
)
272 init_file
= mc_config_get_full_path ("bashrc");
274 if (access (init_file
, R_OK
) == -1)
277 init_file
= g_strdup (".bashrc");
280 /* Make MC's special commands not show up in bash's history */
281 putenv ((char *) "HISTCONTROL=ignorespace");
283 /* Allow alternative readline settings for MC */
285 char *input_file
= mc_config_get_full_path ("inputrc");
286 if (access (input_file
, R_OK
) == 0)
288 char *putenv_str
= g_strconcat ("INPUTRC=", input_file
, NULL
);
297 /* TODO: Find a way to pass initfile to TCSH and ZSH */
304 fprintf (stderr
, __FILE__
": unimplemented subshell type %d\r\n", subshell_type
);
305 my_exit (FORK_FAILURE
);
308 /* Attach all our standard file descriptors to the pty */
310 /* This is done just before the fork, because stderr must still */
311 /* be connected to the real tty during the above error messages; */
312 /* otherwise the user will never see them. */
314 dup2 (subshell_pty_slave
, STDIN_FILENO
);
315 dup2 (subshell_pty_slave
, STDOUT_FILENO
);
316 dup2 (subshell_pty_slave
, STDERR_FILENO
);
318 close (subshell_pipe
[READ
]);
319 close (subshell_pty_slave
); /* These may be FD_CLOEXEC, but just in case... */
320 /* Close master side of pty. This is important; apart from */
321 /* freeing up the descriptor for use in the subshell, it also */
322 /* means that when MC exits, the subshell will get a SIGHUP and */
323 /* exit too, because there will be no more descriptors pointing */
324 /* at the master side of the pty and so it will disappear. */
325 close (mc_global
.tty
.subshell_pty
);
327 /* Execute the subshell at last */
329 switch (subshell_type
)
332 execl (mc_global
.tty
.shell
, "bash", "-rcfile", init_file
, (char *) NULL
);
336 execl (mc_global
.tty
.shell
, "tcsh", (char *) NULL
);
340 /* Use -g to exclude cmds beginning with space from history
341 * and -Z to use the line editor on non-interactive term */
342 execl (mc_global
.tty
.shell
, "zsh", "-Z", "-g", (char *) NULL
);
347 execl (mc_global
.tty
.shell
, "fish", (char *) NULL
);
351 /* If we get this far, everything failed miserably */
353 my_exit (FORK_FAILURE
);
357 /* --------------------------------------------------------------------------------------------- */
359 * Check MC_SID to prevent running one mc from another.
361 * 0 if no parent mc in our session was found,
362 * 1 if parent mc was found and the user wants to continue,
363 * 2 if parent mc was found and the user wants to quit mc.
369 pid_t my_sid
, old_sid
;
373 sid_str
= getenv ("MC_SID");
377 old_sid
= (pid_t
) strtol (sid_str
, NULL
, 0);
385 /* The parent mc is in a different session, it's OK */
386 if (old_sid
!= my_sid
)
389 r
= query_dialog (_("Warning"),
390 _("GNU Midnight Commander is already\n"
391 "running on this terminal.\n"
392 "Subshell support will be disabled."), D_ERROR
, 2, _("&OK"), _("&Quit"));
401 /* --------------------------------------------------------------------------------------------- */
406 static int initialized
= 0;
408 /* MC calls tty_reset_shell_mode() in pre_exec() to set the real tty to its */
409 /* original settings. However, here we need to make this tty very raw, */
410 /* so that all keyboard signals, XON/XOFF, etc. will get through to the */
411 /* pty. So, instead of changing the code for execute(), pre_exec(), */
412 /* etc, we just set up the modes we need here, before each command. */
414 if (initialized
== 0) /* First time: initialise 'raw_mode' */
416 tcgetattr (STDOUT_FILENO
, &raw_mode
);
417 raw_mode
.c_lflag
&= ~ICANON
; /* Disable line-editing chars, etc. */
418 raw_mode
.c_lflag
&= ~ISIG
; /* Disable intr, quit & suspend chars */
419 raw_mode
.c_lflag
&= ~ECHO
; /* Disable input echoing */
420 raw_mode
.c_iflag
&= ~IXON
; /* Pass ^S/^Q to subshell undisturbed */
421 raw_mode
.c_iflag
&= ~ICRNL
; /* Don't translate CRs into LFs */
422 raw_mode
.c_oflag
&= ~OPOST
; /* Don't postprocess output */
423 raw_mode
.c_cc
[VTIME
] = 0; /* IE: wait forever, and return as */
424 raw_mode
.c_cc
[VMIN
] = 1; /* soon as a character is available */
429 /* --------------------------------------------------------------------------------------------- */
431 * Wait until the subshell dies or stops. If it stops, make it resume.
432 * Possibly modifies the globals 'subshell_alive' and 'subshell_stopped'
438 sigset_t sigchld_mask
, old_mask
;
440 sigemptyset (&sigchld_mask
);
441 sigaddset (&sigchld_mask
, SIGCHLD
);
442 sigprocmask (SIG_BLOCK
, &sigchld_mask
, &old_mask
);
445 * SIGCHLD should not be blocked, but we unblock it just in case.
446 * This is known to be useful for cygwin 1.3.12 and older.
448 sigdelset (&old_mask
, SIGCHLD
);
450 /* Wait until the subshell has stopped */
451 while (subshell_alive
&& !subshell_stopped
)
452 sigsuspend (&old_mask
);
454 if (subshell_state
!= ACTIVE
)
456 /* Discard all remaining data from stdin to the subshell */
457 tcflush (subshell_pty_slave
, TCIFLUSH
);
460 subshell_stopped
= FALSE
;
461 kill (subshell_pid
, SIGCONT
);
463 sigprocmask (SIG_SETMASK
, &old_mask
, NULL
);
464 /* We can't do any better without modifying the shell(s) */
467 /* --------------------------------------------------------------------------------------------- */
468 /** Feed the subshell our keyboard input until it says it's finished */
471 feed_subshell (int how
, int fail_on_error
)
473 fd_set read_set
; /* For 'select' */
475 int bytes
; /* For the return value from 'read' */
476 int i
; /* Loop counter */
478 struct timeval wtime
; /* Maximum time we wait for the subshell */
479 struct timeval
*wptr
;
481 /* we wait up to 10 seconds if fail_on_error, forever otherwise */
484 wptr
= fail_on_error
? &wtime
: NULL
;
491 /* Prepare the file-descriptor set and call 'select' */
494 FD_SET (mc_global
.tty
.subshell_pty
, &read_set
);
495 FD_SET (subshell_pipe
[READ
], &read_set
);
496 maxfdp
= max (mc_global
.tty
.subshell_pty
, subshell_pipe
[READ
]);
499 FD_SET (STDIN_FILENO
, &read_set
);
500 maxfdp
= max (maxfdp
, STDIN_FILENO
);
503 if (select (maxfdp
+ 1, &read_set
, NULL
, NULL
, wptr
) == -1)
505 /* Despite using SA_RESTART, we still have to check for this */
508 if (mc_global
.tty
.winch_flag
!= 0)
509 tty_change_screen_size ();
511 continue; /* try all over again */
513 tcsetattr (STDOUT_FILENO
, TCSANOW
, &shell_mode
);
514 fprintf (stderr
, "select (FD_SETSIZE, &read_set...): %s\r\n",
515 unix_error_string (errno
));
519 if (FD_ISSET (mc_global
.tty
.subshell_pty
, &read_set
))
520 /* Read from the subshell, write to stdout */
522 /* This loop improves performance by reducing context switches
523 by a factor of 20 or so... unfortunately, it also hangs MC
524 randomly, because of an apparent Linux bug. Investigate. */
525 /* for (i=0; i<5; ++i) * FIXME -- experimental */
527 bytes
= read (mc_global
.tty
.subshell_pty
, pty_buffer
, sizeof (pty_buffer
));
529 /* The subshell has died */
530 if (bytes
== -1 && errno
== EIO
&& !subshell_alive
)
535 tcsetattr (STDOUT_FILENO
, TCSANOW
, &shell_mode
);
536 fprintf (stderr
, "read (subshell_pty...): %s\r\n", unix_error_string (errno
));
541 write_all (STDOUT_FILENO
, pty_buffer
, bytes
);
544 else if (FD_ISSET (subshell_pipe
[READ
], &read_set
))
545 /* Read the subshell's CWD and capture its prompt */
547 bytes
= read (subshell_pipe
[READ
], subshell_cwd
, MC_MAXPATHLEN
+ 1);
550 tcsetattr (STDOUT_FILENO
, TCSANOW
, &shell_mode
);
551 fprintf (stderr
, "read (subshell_pipe[READ]...): %s\r\n",
552 unix_error_string (errno
));
556 subshell_cwd
[bytes
- 1] = 0; /* Squash the final '\n' */
560 subshell_ready
= TRUE
;
561 if (subshell_state
== RUNNING_COMMAND
)
563 subshell_state
= INACTIVE
;
568 else if (FD_ISSET (STDIN_FILENO
, &read_set
))
569 /* Read from stdin, write to the subshell */
571 bytes
= read (STDIN_FILENO
, pty_buffer
, sizeof (pty_buffer
));
574 tcsetattr (STDOUT_FILENO
, TCSANOW
, &shell_mode
);
576 "read (STDIN_FILENO, pty_buffer...): %s\r\n", unix_error_string (errno
));
580 for (i
= 0; i
< bytes
; ++i
)
581 if (pty_buffer
[i
] == subshell_switch_key
)
583 write_all (mc_global
.tty
.subshell_pty
, pty_buffer
, i
);
585 subshell_state
= INACTIVE
;
589 write_all (mc_global
.tty
.subshell_pty
, pty_buffer
, bytes
);
591 if (pty_buffer
[bytes
- 1] == '\n' || pty_buffer
[bytes
- 1] == '\r')
592 subshell_ready
= FALSE
;
599 /* --------------------------------------------------------------------------------------------- */
600 /* pty opening functions */
604 /* System V version of pty_open_master */
607 pty_open_master (char *pty_name
)
612 #ifdef HAVE_POSIX_OPENPT
613 pty_master
= posix_openpt (O_RDWR
);
615 /* getpt () is a GNU extension (glibc 2.1.x) */
616 pty_master
= getpt ();
618 strcpy (pty_name
, "/dev/ptc");
619 pty_master
= open (pty_name
, O_RDWR
);
621 strcpy (pty_name
, "/dev/ptmx");
622 pty_master
= open (pty_name
, O_RDWR
);
625 if (pty_master
== -1)
628 if (grantpt (pty_master
) == -1 /* Grant access to slave */
629 || unlockpt (pty_master
) == -1 /* Clear slave's lock flag */
630 || !(slave_name
= ptsname (pty_master
))) /* Get slave's name */
635 strcpy (pty_name
, slave_name
);
639 /* --------------------------------------------------------------------------------------------- */
640 /** System V version of pty_open_slave */
643 pty_open_slave (const char *pty_name
)
645 int pty_slave
= open (pty_name
, O_RDWR
);
649 fprintf (stderr
, "open (%s, O_RDWR): %s\r\n", pty_name
, unix_error_string (errno
));
652 #if !defined(__osf__) && !defined(__linux__)
653 #if defined (I_FIND) && defined (I_PUSH)
654 if (!ioctl (pty_slave
, I_FIND
, "ptem"))
655 if (ioctl (pty_slave
, I_PUSH
, "ptem") == -1)
657 fprintf (stderr
, "ioctl (%d, I_PUSH, \"ptem\") failed: %s\r\n",
658 pty_slave
, unix_error_string (errno
));
663 if (!ioctl (pty_slave
, I_FIND
, "ldterm"))
664 if (ioctl (pty_slave
, I_PUSH
, "ldterm") == -1)
667 "ioctl (%d, I_PUSH, \"ldterm\") failed: %s\r\n",
668 pty_slave
, unix_error_string (errno
));
672 #if !defined(sgi) && !defined(__sgi)
673 if (!ioctl (pty_slave
, I_FIND
, "ttcompat"))
674 if (ioctl (pty_slave
, I_PUSH
, "ttcompat") == -1)
677 "ioctl (%d, I_PUSH, \"ttcompat\") failed: %s\r\n",
678 pty_slave
, unix_error_string (errno
));
682 #endif /* sgi || __sgi */
683 #endif /* I_FIND && I_PUSH */
684 #endif /* __osf__ || __linux__ */
686 fcntl (pty_slave
, F_SETFD
, FD_CLOEXEC
);
690 #else /* !HAVE_GRANTPT */
692 /* --------------------------------------------------------------------------------------------- */
693 /** BSD version of pty_open_master */
695 pty_open_master (char *pty_name
)
698 const char *ptr1
, *ptr2
;
700 strcpy (pty_name
, "/dev/ptyXX");
701 for (ptr1
= "pqrstuvwxyzPQRST"; *ptr1
; ++ptr1
)
704 for (ptr2
= "0123456789abcdef"; *ptr2
!= '\0'; ++ptr2
)
708 /* Try to open master */
709 pty_master
= open (pty_name
, O_RDWR
);
710 if (pty_master
== -1)
712 if (errno
== ENOENT
) /* Different from EIO */
713 return -1; /* Out of pty devices */
714 continue; /* Try next pty device */
716 pty_name
[5] = 't'; /* Change "pty" to "tty" */
717 if (access (pty_name
, 6) != 0)
726 return -1; /* Ran out of pty devices */
729 /* --------------------------------------------------------------------------------------------- */
730 /** BSD version of pty_open_slave */
733 pty_open_slave (const char *pty_name
)
736 struct group
*group_info
= getgrnam ("tty");
738 if (group_info
!= NULL
)
740 /* The following two calls will only succeed if we are root */
741 /* [Commented out while permissions problem is investigated] */
742 /* chown (pty_name, getuid (), group_info->gr_gid); FIXME */
743 /* chmod (pty_name, S_IRUSR | S_IWUSR | S_IWGRP); FIXME */
745 pty_slave
= open (pty_name
, O_RDWR
);
747 fprintf (stderr
, "open (pty_name, O_RDWR): %s\r\n", pty_name
);
748 fcntl (pty_slave
, F_SETFD
, FD_CLOEXEC
);
751 #endif /* !HAVE_GRANTPT */
753 /* --------------------------------------------------------------------------------------------- */
754 /*** public functions ****************************************************************************/
755 /* --------------------------------------------------------------------------------------------- */
757 /* --------------------------------------------------------------------------------------------- */
759 * Fork the subshell, and set up many, many things.
761 * Possibly modifies the global variables:
762 * subshell_type, subshell_alive, subshell_stopped, subshell_pid
763 * mc_global.tty.use_subshell - Is set to FALSE if we can't run the subshell
764 * quit - Can be set to SUBSHELL_EXIT by the SIGCHLD handler
770 /* This must be remembered across calls to init_subshell() */
771 static char pty_name
[BUF_SMALL
];
772 char precmd
[BUF_SMALL
];
774 switch (check_sid ())
777 mc_global
.tty
.use_subshell
= FALSE
;
780 mc_global
.tty
.use_subshell
= FALSE
;
781 mc_global
.midnight_shutdown
= TRUE
;
785 /* Take the current (hopefully pristine) tty mode and make */
786 /* a raw mode based on it now, before we do anything else with it */
789 if (mc_global
.tty
.subshell_pty
== 0)
790 { /* First time through */
791 /* Find out what type of shell we have */
793 if (strstr (mc_global
.tty
.shell
, "/zsh") || getenv ("ZSH_VERSION"))
795 else if (strstr (mc_global
.tty
.shell
, "/tcsh"))
796 subshell_type
= TCSH
;
797 else if (strstr (mc_global
.tty
.shell
, "/csh"))
798 subshell_type
= TCSH
;
799 else if (strstr (mc_global
.tty
.shell
, "/bash") || getenv ("BASH"))
800 subshell_type
= BASH
;
801 else if (strstr (mc_global
.tty
.shell
, "/fish"))
802 subshell_type
= FISH
;
805 mc_global
.tty
.use_subshell
= FALSE
;
809 /* Open a pty for talking to the subshell */
811 /* FIXME: We may need to open a fresh pty each time on SVR4 */
813 mc_global
.tty
.subshell_pty
= pty_open_master (pty_name
);
814 if (mc_global
.tty
.subshell_pty
== -1)
816 fprintf (stderr
, "Cannot open master side of pty: %s\r\n", unix_error_string (errno
));
817 mc_global
.tty
.use_subshell
= FALSE
;
820 subshell_pty_slave
= pty_open_slave (pty_name
);
821 if (subshell_pty_slave
== -1)
823 fprintf (stderr
, "Cannot open slave side of pty %s: %s\r\n",
824 pty_name
, unix_error_string (errno
));
825 mc_global
.tty
.use_subshell
= FALSE
;
829 /* Create a pipe for receiving the subshell's CWD */
831 if (subshell_type
== TCSH
)
833 g_snprintf (tcsh_fifo
, sizeof (tcsh_fifo
), "%s/mc.pipe.%d",
834 mc_tmpdir (), (int) getpid ());
835 if (mkfifo (tcsh_fifo
, 0600) == -1)
837 fprintf (stderr
, "mkfifo(%s) failed: %s\r\n", tcsh_fifo
, unix_error_string (errno
));
838 mc_global
.tty
.use_subshell
= FALSE
;
842 /* Opening the FIFO as O_RDONLY or O_WRONLY causes deadlock */
844 if ((subshell_pipe
[READ
] = open (tcsh_fifo
, O_RDWR
)) == -1
845 || (subshell_pipe
[WRITE
] = open (tcsh_fifo
, O_RDWR
)) == -1)
847 fprintf (stderr
, _("Cannot open named pipe %s\n"), tcsh_fifo
);
848 perror (__FILE__
": open");
849 mc_global
.tty
.use_subshell
= FALSE
;
853 else /* subshell_type is BASH or ZSH */ if (pipe (subshell_pipe
))
855 perror (__FILE__
": couldn't create pipe");
856 mc_global
.tty
.use_subshell
= FALSE
;
861 /* Fork the subshell */
863 subshell_alive
= TRUE
;
864 subshell_stopped
= FALSE
;
865 subshell_pid
= fork ();
867 if (subshell_pid
== -1)
869 fprintf (stderr
, "Cannot spawn the subshell process: %s\r\n", unix_error_string (errno
));
870 /* We exit here because, if the process table is full, the */
871 /* other method of running user commands won't work either */
875 if (subshell_pid
== 0)
877 /* We are in the child process */
878 init_subshell_child (pty_name
);
881 /* Set up 'precmd' or equivalent for reading the subshell's CWD */
883 switch (subshell_type
)
886 g_snprintf (precmd
, sizeof (precmd
),
887 " PROMPT_COMMAND='pwd>&%d;kill -STOP $$'\n", subshell_pipe
[WRITE
]);
891 g_snprintf (precmd
, sizeof (precmd
),
892 " precmd(){ pwd>&%d;kill -STOP $$ }\n", subshell_pipe
[WRITE
]);
896 g_snprintf (precmd
, sizeof (precmd
),
897 "set echo_style=both;"
898 "alias precmd 'echo $cwd:q >>%s;kill -STOP $$'\n", tcsh_fifo
);
901 g_snprintf (precmd
, sizeof (precmd
),
902 "function fish_prompt ; pwd>&%d;kill -STOP %%self; end\n",
903 subshell_pipe
[WRITE
]);
907 write_all (mc_global
.tty
.subshell_pty
, precmd
, strlen (precmd
));
909 /* Wait until the subshell has started up and processed the command */
911 subshell_state
= RUNNING_COMMAND
;
912 tty_enable_interrupt_key ();
913 if (!feed_subshell (QUIETLY
, TRUE
))
915 mc_global
.tty
.use_subshell
= FALSE
;
917 tty_disable_interrupt_key ();
919 mc_global
.tty
.use_subshell
= FALSE
; /* Subshell died instantly, so don't use it */
922 /* --------------------------------------------------------------------------------------------- */
925 invoke_subshell (const char *command
, int how
, vfs_path_t
** new_dir_vpath
)
929 /* Make the MC terminal transparent */
930 tcsetattr (STDOUT_FILENO
, TCSANOW
, &raw_mode
);
932 /* Make the subshell change to MC's working directory */
933 if (new_dir_vpath
!= NULL
)
934 do_subshell_chdir (current_panel
->cwd_vpath
, TRUE
);
936 if (command
== NULL
) /* The user has done "C-o" from MC */
938 if (subshell_state
== INACTIVE
)
940 subshell_state
= ACTIVE
;
941 /* FIXME: possibly take out this hack; the user can
942 re-play it by hitting C-hyphen a few times! */
944 write_all (mc_global
.tty
.subshell_pty
, " \b", 2); /* Hack to make prompt reappear */
947 else /* MC has passed us a user command */
950 write_all (mc_global
.tty
.subshell_pty
, " ", 1);
951 /* FIXME: if command is long (>8KB ?) we go comma */
952 write_all (mc_global
.tty
.subshell_pty
, command
, strlen (command
));
953 write_all (mc_global
.tty
.subshell_pty
, "\n", 1);
954 subshell_state
= RUNNING_COMMAND
;
955 subshell_ready
= FALSE
;
958 feed_subshell (how
, FALSE
);
960 pcwd
= vfs_translate_path_n (vfs_path_as_str (current_panel
->cwd_vpath
));
962 if (new_dir_vpath
!= NULL
&& subshell_alive
&& strcmp (subshell_cwd
, pcwd
))
963 *new_dir_vpath
= vfs_path_from_str (subshell_cwd
); /* Make MC change to the subshell's CWD */
966 /* Restart the subshell if it has died by SIGHUP, SIGQUIT, etc. */
967 while (!subshell_alive
&& quit
== 0 && mc_global
.tty
.use_subshell
)
974 /* --------------------------------------------------------------------------------------------- */
977 read_subshell_prompt (void)
981 struct timeval timeleft
= { 0, 0 };
983 gboolean prompt_was_reset
= FALSE
;
987 FD_SET (mc_global
.tty
.subshell_pty
, &tmp
);
989 /* First time through */
990 if (subshell_prompt
== NULL
)
991 subshell_prompt
= g_string_sized_new (INITIAL_PROMPT_SIZE
);
993 p
= g_string_sized_new (INITIAL_PROMPT_SIZE
);
995 while (subshell_alive
996 && (rc
= select (mc_global
.tty
.subshell_pty
+ 1, &tmp
, NULL
, NULL
, &timeleft
)) != 0)
1000 /* Check for 'select' errors */
1005 if (mc_global
.tty
.winch_flag
!= 0)
1006 tty_change_screen_size ();
1011 fprintf (stderr
, "select (FD_SETSIZE, &tmp...): %s\r\n", unix_error_string (errno
));
1012 exit (EXIT_FAILURE
);
1015 bytes
= read (mc_global
.tty
.subshell_pty
, pty_buffer
, sizeof (pty_buffer
));
1017 /* Extract the prompt from the shell output */
1018 for (i
= 0; i
< bytes
; i
++)
1019 if (pty_buffer
[i
] == '\n' || pty_buffer
[i
] == '\r')
1021 g_string_set_size (p
, 0);
1022 prompt_was_reset
= TRUE
;
1024 else if (pty_buffer
[i
] != '\0')
1025 g_string_append_c (p
, pty_buffer
[i
]);
1028 if (p
->len
!= 0 || prompt_was_reset
)
1029 g_string_assign (subshell_prompt
, p
->str
);
1031 g_string_free (p
, TRUE
);
1033 return (rc
!= 0 || bytes
!= 0);
1036 /* --------------------------------------------------------------------------------------------- */
1039 do_update_prompt (void)
1041 if (update_subshell_prompt
)
1043 printf ("\r\n%s", subshell_prompt
->str
);
1045 update_subshell_prompt
= FALSE
;
1049 /* --------------------------------------------------------------------------------------------- */
1052 exit_subshell (void)
1054 gboolean subshell_quit
= TRUE
;
1056 if (subshell_state
!= INACTIVE
&& subshell_alive
)
1058 query_dialog (_("Warning"),
1059 _("The shell is still active. Quit anyway?"),
1060 D_NORMAL
, 2, _("&Yes"), _("&No")) == 0;
1064 if (subshell_type
== TCSH
)
1066 if (unlink (tcsh_fifo
) == -1)
1067 fprintf (stderr
, "Cannot remove named pipe %s: %s\r\n",
1068 tcsh_fifo
, unix_error_string (errno
));
1071 g_string_free (subshell_prompt
, TRUE
);
1072 subshell_prompt
= NULL
;
1073 pty_buffer
[0] = '\0';
1076 return subshell_quit
;
1079 /* --------------------------------------------------------------------------------------------- */
1081 * Carefully quote directory name to allow entering any directory safely,
1082 * no matter what weird characters it may contain in its name.
1083 * NOTE: Treat directory name an untrusted data, don't allow it to cause
1084 * executing any commands in the shell. Escape all control characters.
1085 * Use following technique:
1087 * printf(1) with format string containing a single conversion specifier,
1088 * "b", and an argument which contains a copy of the string passed to
1089 * subshell_name_quote() with all characters, except digits and letters,
1090 * replaced by the backslash-escape sequence \0nnn, where "nnn" is the
1091 * numeric value of the character converted to octal number.
1093 * cd "`printf "%b" 'ABC\0nnnDEF\0nnnXYZ'`"
1098 subshell_name_quote (const char *s
)
1102 const char *quote_cmd_start
, *quote_cmd_end
;
1104 if (subshell_type
== FISH
)
1106 quote_cmd_start
= "(printf \"%b\" '";
1107 quote_cmd_end
= "')";
1111 quote_cmd_start
= "\"`printf \"%b\" '";
1112 quote_cmd_end
= "'`\"";
1115 ret
= g_string_sized_new (64);
1117 /* Prevent interpreting leading '-' as a switch for 'cd' */
1119 g_string_append (ret
, "./");
1121 /* Copy the beginning of the command to the buffer */
1122 g_string_append (ret
, quote_cmd_start
);
1125 * Print every character except digits and letters as a backslash-escape
1126 * sequence of the form \0nnn, where "nnn" is the numeric value of the
1127 * character converted to octal number.
1129 for (su
= s
; su
[0] != '\0'; su
= n
)
1131 n
= str_cget_next_char_safe (su
);
1133 if (str_isalnum (su
))
1134 g_string_append_len (ret
, su
, n
- su
);
1139 for (c
= 0; c
< n
- su
; c
++)
1140 g_string_append_printf (ret
, "\\0%03o", (unsigned char) su
[c
]);
1144 g_string_append (ret
, quote_cmd_end
);
1150 /* --------------------------------------------------------------------------------------------- */
1152 /** If it actually changed the directory it returns true */
1154 do_subshell_chdir (const vfs_path_t
* vpath
, gboolean update_prompt
)
1158 pcwd
= vfs_path_to_str_flags (current_panel
->cwd_vpath
, 0, VPF_RECODE
);
1160 if (!(subshell_state
== INACTIVE
&& strcmp (subshell_cwd
, pcwd
) != 0))
1162 /* We have to repaint the subshell prompt if we read it from
1163 * the main program. Please note that in the code after this
1164 * if, the cd command that is sent will make the subshell
1165 * repaint the prompt, so we don't have to paint it. */
1167 do_update_prompt ();
1172 /* The initial space keeps this out of the command history (in bash
1173 because we set "HISTCONTROL=ignorespace") */
1174 write_all (mc_global
.tty
.subshell_pty
, " cd ", 4);
1180 translate
= vfs_translate_path_n (vfs_path_as_str (vpath
));
1181 if (translate
!= NULL
)
1185 temp
= subshell_name_quote (translate
);
1186 write_all (mc_global
.tty
.subshell_pty
, temp
->str
, temp
->len
);
1187 g_string_free (temp
, TRUE
);
1193 write_all (mc_global
.tty
.subshell_pty
, ".", 1);
1198 write_all (mc_global
.tty
.subshell_pty
, "/", 1);
1200 write_all (mc_global
.tty
.subshell_pty
, "\n", 1);
1202 subshell_state
= RUNNING_COMMAND
;
1203 feed_subshell (QUIETLY
, FALSE
);
1207 int bPathNotEq
= strcmp (subshell_cwd
, pcwd
);
1209 if (bPathNotEq
&& subshell_type
== TCSH
)
1211 char rp_subshell_cwd
[PATH_MAX
];
1212 char rp_current_panel_cwd
[PATH_MAX
];
1214 char *p_subshell_cwd
= mc_realpath (subshell_cwd
, rp_subshell_cwd
);
1215 char *p_current_panel_cwd
= mc_realpath (pcwd
, rp_current_panel_cwd
);
1217 if (p_subshell_cwd
== NULL
)
1218 p_subshell_cwd
= subshell_cwd
;
1219 if (p_current_panel_cwd
== NULL
)
1220 p_current_panel_cwd
= pcwd
;
1221 bPathNotEq
= strcmp (p_subshell_cwd
, p_current_panel_cwd
);
1224 if (bPathNotEq
&& !DIR_IS_DOT (pcwd
))
1228 cwd
= vfs_path_to_str_flags (current_panel
->cwd_vpath
, 0, VPF_STRIP_PASSWORD
);
1229 vfs_print_message (_("Warning: Cannot change to %s.\n"), cwd
);
1234 update_subshell_prompt
= FALSE
;
1237 /* Make sure that MC never stores the CWD in a silly format */
1238 /* like /usr////lib/../bin, or the strcmp() above will fail */
1241 /* --------------------------------------------------------------------------------------------- */
1244 subshell_get_console_attributes (void)
1246 /* Get our current terminal modes */
1248 if (tcgetattr (STDOUT_FILENO
, &shell_mode
))
1250 fprintf (stderr
, "Cannot get terminal settings: %s\r\n", unix_error_string (errno
));
1251 mc_global
.tty
.use_subshell
= FALSE
;
1255 /* --------------------------------------------------------------------------------------------- */
1257 * Figure out whether the subshell has stopped, exited or been killed
1258 * Possibly modifies: 'subshell_alive', 'subshell_stopped' and 'quit' */
1261 sigchld_handler (int sig
)
1268 pid
= waitpid (subshell_pid
, &status
, WUNTRACED
| WNOHANG
);
1270 if (pid
== subshell_pid
)
1272 /* Figure out what has happened to the subshell */
1274 if (WIFSTOPPED (status
))
1276 if (WSTOPSIG (status
) == SIGSTOP
)
1278 /* The subshell has received a SIGSTOP signal */
1279 subshell_stopped
= TRUE
;
1283 /* The user has suspended the subshell. Revive it */
1284 kill (subshell_pid
, SIGCONT
);
1289 /* The subshell has either exited normally or been killed */
1290 subshell_alive
= FALSE
;
1291 delete_select_channel (mc_global
.tty
.subshell_pty
);
1292 if (WIFEXITED (status
) && WEXITSTATUS (status
) != FORK_FAILURE
)
1293 quit
|= SUBSHELL_EXIT
; /* Exited normally */
1297 pid
= waitpid (cons_saver_pid
, &status
, WUNTRACED
| WNOHANG
);
1299 if (pid
== cons_saver_pid
)
1302 if (WIFSTOPPED (status
))
1303 /* Someone has stopped cons.saver - restart it */
1304 kill (pid
, SIGCONT
);
1307 /* cons.saver has died - disable confole saving */
1308 handle_console (CONSOLE_DONE
);
1309 mc_global
.tty
.console_flag
= '\0';
1313 #endif /* __linux__ */
1315 /* If we got here, some other child exited; ignore it */
1318 /* --------------------------------------------------------------------------------------------- */