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-rw-r--r--src/subshell/common.c1870
1 files changed, 1870 insertions, 0 deletions
diff --git a/src/subshell/common.c b/src/subshell/common.c
new file mode 100644
index 0000000..61bf527
--- /dev/null
+++ b/src/subshell/common.c
@@ -0,0 +1,1870 @@
+/*
+ Concurrent shell support for the Midnight Commander
+
+ Copyright (C) 1994-2022
+ Free Software Foundation, Inc.
+
+ Written by:
+ Alexander Kriegisch <Alexander@Kriegisch.name>
+ Aliaksey Kandratsenka <alk@tut.by>
+ Andreas Mohr <and@gmx.li>
+ Andrew Borodin <aborodin@vmail.ru>
+ Andrew V. Samoilov <sav@bcs.zp.ua>
+ Chris Owen <chris@candu.co.uk>
+ Claes Nästén <me@pekdon.net>
+ Egmont Koblinger <egmont@gmail.com>
+ Enrico Weigelt, metux IT service <weigelt@metux.de>
+ Eric Roberts <ericmrobertsdeveloper@gmail.com>
+ Igor Urazov <z0rc3r@gmail.com>
+ Ilia Maslakov <il.smind@gmail.com>
+ Leonard den Ottolander <leonard@den.ottolander.nl>
+ Miguel de Icaza <miguel@novell.com>
+ Mikhail S. Pobolovets <styx.mp@gmail.com>
+ Norbert Warmuth <nwarmuth@privat.circular.de>
+ Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
+ Patrick Winnertz <winnie@debian.org>
+ Pavel Machek <pavel@suse.cz>
+ Pavel Roskin <proski@gnu.org>
+ Pavel Tsekov <ptsekov@gmx.net>
+ Roland Illig <roland.illig@gmx.de>
+ Sergei Trofimovich <slyfox@inbox.ru>
+ Slava Zanko <slavazanko@gmail.com>
+ Timur Bakeyev <mc@bat.ru>
+ Vit Rosin <vit_r@list.ru>
+
+ This file is part of the Midnight Commander.
+
+ The Midnight Commander 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 3 of the License,
+ or (at your option) any later version.
+
+ The Midnight Commander 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, see <http://www.gnu.org/licenses/>.
+ */
+
+/** \file subshell.c
+ * \brief Source: concurrent shell support
+ */
+
+#include <config.h>
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <signal.h>
+#ifdef HAVE_SYS_SELECT_H
+#include <sys/select.h>
+#else
+#include <sys/time.h>
+#include <unistd.h>
+#endif
+#include <sys/types.h>
+#include <sys/wait.h>
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#include <termios.h>
+
+#ifdef HAVE_STROPTS_H
+#include <stropts.h> /* For I_PUSH */
+#endif /* HAVE_STROPTS_H */
+
+#ifdef HAVE_OPENPTY
+/* includes for openpty() */
+#ifdef HAVE_PTY_H
+#include <pty.h>
+#endif
+#ifdef HAVE_UTIL_H
+#include <util.h>
+#endif
+/* <sys/types.h> is a prerequisite of <libutil.h> on FreeBSD 8.0. */
+#ifdef HAVE_LIBUTIL_H
+#include <libutil.h>
+#endif
+#endif /* HAVE_OPENPTY */
+
+#include "lib/global.h"
+
+#include "lib/fileloc.h"
+#include "lib/unixcompat.h"
+#include "lib/tty/tty.h" /* LINES */
+#include "lib/tty/key.h" /* XCTRL */
+#include "lib/vfs/vfs.h"
+#include "lib/strutil.h"
+#include "lib/mcconfig.h"
+#include "lib/util.h"
+#include "lib/widget.h"
+
+#include "src/filemanager/layout.h" /* setup_cmdline() */
+#include "src/filemanager/command.h" /* cmdline */
+
+#include "subshell.h"
+#include "internal.h"
+
+/*** global variables ****************************************************************************/
+
+/* State of the subshell:
+ * INACTIVE: the default state; awaiting a command
+ * ACTIVE: remain in the shell until the user hits 'subshell_switch_key'
+ * RUNNING_COMMAND: return to MC when the current command finishes */
+enum subshell_state_enum subshell_state;
+
+/* Holds the latest prompt captured from the subshell */
+GString *subshell_prompt = NULL;
+
+/* Subshell: if set, then the prompt was not saved on CONSOLE_SAVE */
+/* We need to paint it after CONSOLE_RESTORE, see: load_prompt */
+gboolean update_subshell_prompt = FALSE;
+
+/* If set, then a command has just finished executing, and we need */
+/* to be on the lookout for a new prompt string from the subshell. */
+gboolean should_read_new_subshell_prompt;
+
+/*** file scope macro definitions ****************************************************************/
+
+#ifndef WEXITSTATUS
+#define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
+#endif
+
+#ifndef WIFEXITED
+#define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
+#endif
+
+/* Initial length of the buffer for the subshell's prompt */
+#define INITIAL_PROMPT_SIZE 10
+
+/* Used by the child process to indicate failure to start the subshell */
+#define FORK_FAILURE 69 /* Arbitrary */
+
+/* Length of the buffer for all I/O with the subshell */
+#define PTY_BUFFER_SIZE BUF_MEDIUM /* Arbitrary; but keep it >= 80 */
+
+/*** file scope type declarations ****************************************************************/
+
+/* For pipes */
+enum
+{
+ READ = 0,
+ WRITE = 1
+};
+
+/* This is the keybinding that is sent to the shell, to make the shell send us the contents of
+ * the current command buffer. */
+#define SHELL_BUFFER_KEYBINDING "_"
+
+/* This is the keybinding that is sent to the shell, to make the shell send us the location of
+ * the cursor. */
+#define SHELL_CURSOR_KEYBINDING "+"
+
+/*** file scope variables ************************************************************************/
+
+/* tcsh closes all non-standard file descriptors, so we have to use a pipe */
+static char tcsh_fifo[128];
+
+static int subshell_pty_slave = -1;
+
+/* The key for switching back to MC from the subshell */
+/* *INDENT-OFF* */
+static const char subshell_switch_key = XCTRL ('o') & 255;
+/* *INDENT-ON* */
+
+/* For reading/writing on the subshell's pty */
+static char pty_buffer[PTY_BUFFER_SIZE] = "\0";
+
+/* To pass CWD info from the subshell to MC */
+static int subshell_pipe[2];
+
+/* To pass command buffer info from the subshell to MC */
+static int command_buffer_pipe[2];
+
+/* The subshell's process ID */
+static pid_t subshell_pid = 1;
+
+/* One extra char for final '\n' */
+static char subshell_cwd[MC_MAXPATHLEN + 1];
+
+/* Flag to indicate whether the subshell is ready for next command */
+static int subshell_ready;
+
+/* Flag to indicate if the subshell supports the persistent buffer feature. */
+static gboolean use_persistent_buffer = FALSE;
+
+/* This is the local variable where the subshell prompt is stored while we are working on it. */
+static GString *subshell_prompt_temp_buffer = NULL;
+
+/* The following two flags can be changed by the SIGCHLD handler. This is */
+/* OK, because the 'int' type is updated atomically on all known machines */
+static volatile int subshell_alive, subshell_stopped;
+
+/* We store the terminal's initial mode here so that we can configure
+ the pty similarly, and also so we can restore the real terminal to
+ sanity if we have to exit abruptly */
+static struct termios shell_mode;
+
+/* This is a transparent mode for the terminal where MC is running on */
+/* It is used when the shell is active, so that the control signals */
+/* are delivered to the shell pty */
+static struct termios raw_mode;
+
+/* --------------------------------------------------------------------------------------------- */
+/*** file scope functions ************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Write all data, even if the write() call is interrupted.
+ */
+
+static ssize_t
+write_all (int fd, const void *buf, size_t count)
+{
+ ssize_t written = 0;
+
+ while (count > 0)
+ {
+ ssize_t ret;
+
+ ret = write (fd, (const unsigned char *) buf + written, count);
+ if (ret < 0)
+ {
+ if (errno == EINTR)
+ {
+ if (tty_got_winch ())
+ tty_change_screen_size ();
+
+ continue;
+ }
+
+ return written > 0 ? written : ret;
+ }
+ count -= ret;
+ written += ret;
+ }
+ return written;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Prepare child process to running the shell and run it.
+ *
+ * Modifies the global variables (in the child process only):
+ * shell_mode
+ *
+ * Returns: never.
+ */
+
+static void
+init_subshell_child (const char *pty_name)
+{
+ char *init_file = NULL;
+ pid_t mc_sid;
+
+ (void) pty_name;
+ setsid (); /* Get a fresh terminal session */
+
+ /* Make sure that it has become our controlling terminal */
+
+ /* Redundant on Linux and probably most systems, but just in case: */
+
+#ifdef TIOCSCTTY
+ ioctl (subshell_pty_slave, TIOCSCTTY, 0);
+#endif
+
+ /* Configure its terminal modes and window size */
+
+ /* Set up the pty with the same termios flags as our own tty */
+ if (tcsetattr (subshell_pty_slave, TCSANOW, &shell_mode))
+ {
+ fprintf (stderr, "Cannot set pty terminal modes: %s\r\n", unix_error_string (errno));
+ my_exit (FORK_FAILURE);
+ }
+
+ /* Set the pty's size (80x25 by default on Linux) according to the */
+ /* size of the real terminal as calculated by ncurses, if possible */
+ tty_resize (subshell_pty_slave);
+
+ /* Set up the subshell's environment and init file name */
+
+ /* It simplifies things to change to our home directory here, */
+ /* and the user's startup file may do a 'cd' command anyway */
+ {
+ int ret;
+
+ ret = chdir (mc_config_get_home_dir ()); /* FIXME? What about when we re-run the subshell? */
+ (void) ret;
+ }
+
+ /* Set MC_SID to prevent running one mc from another */
+ mc_sid = getsid (0);
+ if (mc_sid != -1)
+ {
+ char sid_str[BUF_SMALL];
+
+ g_snprintf (sid_str, sizeof (sid_str), "MC_SID=%ld", (long) mc_sid);
+ putenv (g_strdup (sid_str));
+ }
+
+ switch (mc_global.shell->type)
+ {
+ case SHELL_BASH:
+ /* Do we have a custom init file ~/.local/share/mc/bashrc? */
+ init_file = mc_config_get_full_path (MC_BASHRC_FILE);
+
+ /* Otherwise use ~/.bashrc */
+ if (!exist_file (init_file))
+ {
+ g_free (init_file);
+ init_file = g_strdup (".bashrc");
+ }
+
+ /* Make MC's special commands not show up in bash's history and also suppress
+ * consecutive identical commands*/
+ putenv ((char *) "HISTCONTROL=ignoreboth");
+
+ /* Allow alternative readline settings for MC */
+ {
+ char *input_file;
+
+ input_file = mc_config_get_full_path (MC_INPUTRC_FILE);
+ if (exist_file (input_file))
+ g_setenv ("INPUTRC", input_file, TRUE);
+ g_free (input_file);
+ }
+
+ break;
+
+ case SHELL_ASH_BUSYBOX:
+ case SHELL_DASH:
+ /* Do we have a custom init file ~/.local/share/mc/ashrc? */
+ init_file = mc_config_get_full_path (MC_ASHRC_FILE);
+
+ /* Otherwise use ~/.profile */
+ if (!exist_file (init_file))
+ {
+ g_free (init_file);
+ init_file = g_strdup (".profile");
+ }
+
+ /* Put init file to ENV variable used by ash */
+ g_setenv ("ENV", init_file, TRUE);
+
+ break;
+
+ case SHELL_ZSH:
+ /* ZDOTDIR environment variable is the only way to point zsh
+ * to an other rc file than the default. */
+
+ /* Don't overwrite $ZDOTDIR */
+ if (g_getenv ("ZDOTDIR") != NULL)
+ {
+ /* Do we have a custom init file ~/.local/share/mc/.zshrc?
+ * Otherwise use standard ~/.zshrc */
+ init_file = mc_config_get_full_path (MC_ZSHRC_FILE);
+ if (exist_file (init_file))
+ {
+ /* Set ZDOTDIR to ~/.local/share/mc */
+ g_setenv ("ZDOTDIR", mc_config_get_data_path (), TRUE);
+ }
+ }
+ break;
+
+ /* TODO: Find a way to pass initfile to TCSH and FISH */
+ case SHELL_TCSH:
+ case SHELL_FISH:
+ break;
+
+ default:
+ fprintf (stderr, __FILE__ ": unimplemented subshell type %u\r\n", mc_global.shell->type);
+ my_exit (FORK_FAILURE);
+ }
+
+ /* Attach all our standard file descriptors to the pty */
+
+ /* This is done just before the exec, because stderr must still */
+ /* be connected to the real tty during the above error messages; */
+ /* otherwise the user will never see them. */
+
+ dup2 (subshell_pty_slave, STDIN_FILENO);
+ dup2 (subshell_pty_slave, STDOUT_FILENO);
+ dup2 (subshell_pty_slave, STDERR_FILENO);
+
+ close (subshell_pipe[READ]);
+
+ if (use_persistent_buffer)
+ close (command_buffer_pipe[READ]);
+
+ close (subshell_pty_slave); /* These may be FD_CLOEXEC, but just in case... */
+ /* Close master side of pty. This is important; apart from */
+ /* freeing up the descriptor for use in the subshell, it also */
+ /* means that when MC exits, the subshell will get a SIGHUP and */
+ /* exit too, because there will be no more descriptors pointing */
+ /* at the master side of the pty and so it will disappear. */
+ close (mc_global.tty.subshell_pty);
+
+ /* Execute the subshell at last */
+
+ switch (mc_global.shell->type)
+ {
+ case SHELL_BASH:
+ execl (mc_global.shell->path, "bash", "-rcfile", init_file, (char *) NULL);
+ break;
+
+ case SHELL_ZSH:
+ /* Use -g to exclude cmds beginning with space from history
+ * and -Z to use the line editor on non-interactive term */
+ execl (mc_global.shell->path, "zsh", "-Z", "-g", (char *) NULL);
+ break;
+
+ case SHELL_ASH_BUSYBOX:
+ case SHELL_DASH:
+ case SHELL_TCSH:
+ case SHELL_FISH:
+ execl (mc_global.shell->path, mc_global.shell->path, (char *) NULL);
+ break;
+
+ default:
+ break;
+ }
+
+ /* If we get this far, everything failed miserably */
+ g_free (init_file);
+ my_exit (FORK_FAILURE);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+init_raw_mode (void)
+{
+ static gboolean initialized = FALSE;
+
+ /* MC calls tty_reset_shell_mode() in pre_exec() to set the real tty to its */
+ /* original settings. However, here we need to make this tty very raw, */
+ /* so that all keyboard signals, XON/XOFF, etc. will get through to the */
+ /* pty. So, instead of changing the code for execute(), pre_exec(), */
+ /* etc, we just set up the modes we need here, before each command. */
+
+ if (!initialized) /* First time: initialise 'raw_mode' */
+ {
+ tcgetattr (STDOUT_FILENO, &raw_mode);
+ raw_mode.c_lflag &= ~ICANON; /* Disable line-editing chars, etc. */
+ raw_mode.c_lflag &= ~ISIG; /* Disable intr, quit & suspend chars */
+ raw_mode.c_lflag &= ~ECHO; /* Disable input echoing */
+ raw_mode.c_iflag &= ~IXON; /* Pass ^S/^Q to subshell undisturbed */
+ raw_mode.c_iflag &= ~ICRNL; /* Don't translate CRs into LFs */
+ raw_mode.c_oflag &= ~OPOST; /* Don't postprocess output */
+ raw_mode.c_cc[VTIME] = 0; /* IE: wait forever, and return as */
+ raw_mode.c_cc[VMIN] = 1; /* soon as a character is available */
+ initialized = TRUE;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Wait until the subshell dies or stops. If it stops, make it resume.
+ * Possibly modifies the globals 'subshell_alive' and 'subshell_stopped'
+ */
+
+static void
+synchronize (void)
+{
+ sigset_t sigchld_mask, old_mask;
+
+ sigemptyset (&sigchld_mask);
+ sigaddset (&sigchld_mask, SIGCHLD);
+ sigprocmask (SIG_BLOCK, &sigchld_mask, &old_mask);
+
+ /*
+ * SIGCHLD should not be blocked, but we unblock it just in case.
+ * This is known to be useful for cygwin 1.3.12 and older.
+ */
+ sigdelset (&old_mask, SIGCHLD);
+
+ /* Wait until the subshell has stopped */
+ while (subshell_alive && !subshell_stopped)
+ sigsuspend (&old_mask);
+
+ if (subshell_state != ACTIVE)
+ {
+ /* Discard all remaining data from stdin to the subshell */
+ tcflush (subshell_pty_slave, TCIFLUSH);
+ }
+
+ subshell_stopped = FALSE;
+ kill (subshell_pid, SIGCONT);
+
+ sigprocmask (SIG_SETMASK, &old_mask, NULL);
+ /* We can't do any better without modifying the shell(s) */
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/* Get the contents of the current subshell command line buffer, and */
+/* transfer the contents to the panel command prompt. */
+
+static gboolean
+read_command_line_buffer (gboolean test_mode)
+{
+ char subshell_command_buffer[BUF_LARGE];
+ char subshell_cursor_buffer[BUF_SMALL];
+
+ fd_set read_set;
+ int i;
+ ssize_t bytes;
+ struct timeval subshell_prompt_timer = { 0, 0 };
+ int command_buffer_length;
+ int command_buffer_char_length;
+ int bash_version;
+ int cursor_position;
+ int maxfdp;
+ int rc;
+
+ if (!use_persistent_buffer)
+ return TRUE;
+
+ FD_ZERO (&read_set);
+ FD_SET (command_buffer_pipe[READ], &read_set);
+ maxfdp = command_buffer_pipe[READ];
+
+ /* First, flush the command buffer pipe. This pipe shouldn't be written
+ * to under normal circumstances, but if it somehow does get written
+ * to, we need to make sure to discard whatever data is there before
+ * we try to use it. */
+ while ((rc = select (maxfdp + 1, &read_set, NULL, NULL, &subshell_prompt_timer)) != 0)
+ {
+ if (rc == -1)
+ {
+ if (errno == EINTR)
+ continue;
+
+ return FALSE;
+ }
+
+ if (rc == 1)
+ {
+ bytes = read (command_buffer_pipe[READ], subshell_command_buffer,
+ sizeof (subshell_command_buffer));
+ (void) bytes;
+ }
+ }
+
+ /* get contents of command line buffer */
+ write_all (mc_global.tty.subshell_pty, ESC_STR SHELL_BUFFER_KEYBINDING,
+ sizeof (ESC_STR SHELL_CURSOR_KEYBINDING) - 1);
+
+ subshell_prompt_timer.tv_sec = 1;
+ FD_ZERO (&read_set);
+ FD_SET (command_buffer_pipe[READ], &read_set);
+
+ while ((rc = select (maxfdp + 1, &read_set, NULL, NULL, &subshell_prompt_timer)) != 1)
+ {
+ if (rc == -1)
+ {
+ if (errno == EINTR)
+ continue;
+
+ return FALSE;
+ }
+
+ if (rc == 0)
+ return FALSE;
+ }
+
+ bytes =
+ read (command_buffer_pipe[READ], subshell_command_buffer, sizeof (subshell_command_buffer));
+ if (bytes == 0 || bytes == sizeof (subshell_command_buffer))
+ return FALSE;
+
+ command_buffer_char_length = bytes - 1;
+ subshell_command_buffer[command_buffer_char_length] = '\0';
+ command_buffer_length = str_length (subshell_command_buffer);
+
+ /* get cursor position */
+ write_all (mc_global.tty.subshell_pty, ESC_STR SHELL_CURSOR_KEYBINDING,
+ sizeof (ESC_STR SHELL_CURSOR_KEYBINDING) - 1);
+
+ subshell_prompt_timer.tv_sec = 1;
+ subshell_prompt_timer.tv_usec = 0;
+ FD_ZERO (&read_set);
+ FD_SET (command_buffer_pipe[READ], &read_set);
+
+ while ((rc = select (maxfdp + 1, &read_set, NULL, NULL, &subshell_prompt_timer)) != 1)
+ {
+ if (rc == -1)
+ {
+ if (errno == EINTR)
+ continue;
+
+ return FALSE;
+ }
+
+ if (rc == 0)
+ return FALSE;
+ }
+
+ bytes =
+ read (command_buffer_pipe[READ], subshell_cursor_buffer, sizeof (subshell_cursor_buffer));
+ if (bytes == 0)
+ return FALSE;
+
+ subshell_cursor_buffer[bytes - 1] = '\0';
+ if (mc_global.shell->type == SHELL_BASH)
+ {
+ if (sscanf (subshell_cursor_buffer, "%d:%d", &bash_version, &cursor_position) != 2)
+ return FALSE;
+ }
+ else
+ {
+ if (sscanf (subshell_cursor_buffer, "%d", &cursor_position) != 1)
+ return FALSE;
+ bash_version = 1000;
+ }
+
+ if (test_mode)
+ return TRUE;
+
+ /* Substitute non-text characters in the command buffer, such as tab, or newline, as this
+ * could cause problems. */
+ for (i = 0; i < command_buffer_char_length; i++)
+ if ((unsigned char) subshell_command_buffer[i] < 32
+ || (unsigned char) subshell_command_buffer[i] == 127)
+ subshell_command_buffer[i] = ' ';
+
+ input_assign_text (cmdline, "");
+ input_insert (cmdline, subshell_command_buffer, FALSE);
+
+ if (bash_version < 5) /* implies SHELL_BASH */
+ {
+ /* We need to do this because bash < v5 gives the cursor position in a utf-8 string based
+ * on the location in bytes, not in unicode characters. */
+ char *curr, *stop;
+
+ curr = subshell_command_buffer;
+ stop = curr + cursor_position;
+
+ for (cursor_position = 0; curr < stop; cursor_position++)
+ str_next_char_safe (&curr);
+ }
+ if (cursor_position > command_buffer_length)
+ cursor_position = command_buffer_length;
+ cmdline->point = cursor_position;
+ /* We send any remaining data to STDOUT before we finish. */
+ flush_subshell (0, VISIBLY);
+
+ /* Now we erase the current contents of the command line buffer */
+ if (mc_global.shell->type != SHELL_ZSH)
+ {
+ /* In zsh, we can just press c-u to clear the line, without needing to go to the end of
+ * the line first first. In all other shells, we must go to the end of the line first. */
+
+ /* If we are not at the end of the line, we go to the end. */
+ if (cursor_position != command_buffer_length)
+ {
+ write_all (mc_global.tty.subshell_pty, "\005", 1);
+ if (flush_subshell (1, VISIBLY) != 1)
+ return FALSE;
+ }
+ }
+
+ if (command_buffer_length > 0)
+ {
+ /* Now we clear the line. */
+ write_all (mc_global.tty.subshell_pty, "\025", 1);
+ if (flush_subshell (1, VISIBLY) != 1)
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+clear_subshell_prompt_string (void)
+{
+ if (subshell_prompt_temp_buffer != NULL)
+ g_string_set_size (subshell_prompt_temp_buffer, 0);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+parse_subshell_prompt_string (const char *buffer, int bytes)
+{
+ int i;
+
+ if (mc_global.mc_run_mode != MC_RUN_FULL)
+ return;
+
+ /* First time through */
+ if (subshell_prompt == NULL)
+ subshell_prompt = g_string_sized_new (INITIAL_PROMPT_SIZE);
+ if (subshell_prompt_temp_buffer == NULL)
+ subshell_prompt_temp_buffer = g_string_sized_new (INITIAL_PROMPT_SIZE);
+
+ /* Extract the prompt from the shell output */
+ for (i = 0; i < bytes; i++)
+ if (buffer[i] == '\n' || buffer[i] == '\r')
+ g_string_set_size (subshell_prompt_temp_buffer, 0);
+ else if (buffer[i] != '\0')
+ g_string_append_c (subshell_prompt_temp_buffer, buffer[i]);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+set_prompt_string (void)
+{
+ if (mc_global.mc_run_mode != MC_RUN_FULL)
+ return;
+
+ if (subshell_prompt_temp_buffer->len != 0)
+ mc_g_string_copy (subshell_prompt, subshell_prompt_temp_buffer);
+
+ setup_cmdline ();
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/** Feed the subshell our keyboard input until it says it's finished */
+
+static gboolean
+feed_subshell (int how, gboolean fail_on_error)
+{
+ fd_set read_set; /* For 'select' */
+ int bytes; /* For the return value from 'read' */
+ int i; /* Loop counter */
+
+ struct timeval wtime; /* Maximum time we wait for the subshell */
+ struct timeval *wptr;
+
+ should_read_new_subshell_prompt = FALSE;
+
+ /* have more than enough time to run subshell:
+ wait up to 10 second if fail_on_error, forever otherwise */
+ wtime.tv_sec = 10;
+ wtime.tv_usec = 0;
+ wptr = fail_on_error ? &wtime : NULL;
+
+ while (TRUE)
+ {
+ int maxfdp;
+
+ if (!subshell_alive)
+ return FALSE;
+
+ /* Prepare the file-descriptor set and call 'select' */
+
+ FD_ZERO (&read_set);
+ FD_SET (mc_global.tty.subshell_pty, &read_set);
+ FD_SET (subshell_pipe[READ], &read_set);
+ maxfdp = MAX (mc_global.tty.subshell_pty, subshell_pipe[READ]);
+ if (how == VISIBLY)
+ {
+ FD_SET (STDIN_FILENO, &read_set);
+ maxfdp = MAX (maxfdp, STDIN_FILENO);
+ }
+
+ if (select (maxfdp + 1, &read_set, NULL, NULL, wptr) == -1)
+ {
+ /* Despite using SA_RESTART, we still have to check for this */
+ if (errno == EINTR)
+ {
+ if (tty_got_winch ())
+ tty_change_screen_size ();
+
+ continue; /* try all over again */
+ }
+ tcsetattr (STDOUT_FILENO, TCSANOW, &shell_mode);
+ fprintf (stderr, "select (FD_SETSIZE, &read_set...): %s\r\n",
+ unix_error_string (errno));
+ exit (EXIT_FAILURE);
+ }
+
+ if (FD_ISSET (mc_global.tty.subshell_pty, &read_set))
+ /* Read from the subshell, write to stdout */
+
+ /* This loop improves performance by reducing context switches
+ by a factor of 20 or so... unfortunately, it also hangs MC
+ randomly, because of an apparent Linux bug. Investigate. */
+ /* for (i=0; i<5; ++i) * FIXME -- experimental */
+ {
+ bytes = read (mc_global.tty.subshell_pty, pty_buffer, sizeof (pty_buffer));
+
+ /* The subshell has died */
+ if (bytes == -1 && errno == EIO && !subshell_alive)
+ return FALSE;
+
+ if (bytes <= 0)
+ {
+#ifdef PTY_ZEROREAD
+ /* On IBM i, read(1) can return 0 for a non-closed fd */
+ continue;
+#else
+ tcsetattr (STDOUT_FILENO, TCSANOW, &shell_mode);
+ fprintf (stderr, "read (subshell_pty...): %s\r\n", unix_error_string (errno));
+ exit (EXIT_FAILURE);
+#endif
+ }
+
+ if (how == VISIBLY)
+ write_all (STDOUT_FILENO, pty_buffer, bytes);
+
+ if (should_read_new_subshell_prompt)
+ parse_subshell_prompt_string (pty_buffer, bytes);
+ }
+
+ else if (FD_ISSET (subshell_pipe[READ], &read_set))
+ /* Read the subshell's CWD and capture its prompt */
+ {
+ bytes = read (subshell_pipe[READ], subshell_cwd, sizeof (subshell_cwd));
+ if (bytes <= 0)
+ {
+ tcsetattr (STDOUT_FILENO, TCSANOW, &shell_mode);
+ fprintf (stderr, "read (subshell_pipe[READ]...): %s\r\n",
+ unix_error_string (errno));
+ exit (EXIT_FAILURE);
+ }
+
+ subshell_cwd[bytes - 1] = '\0'; /* Squash the final '\n' */
+
+ synchronize ();
+
+ clear_subshell_prompt_string ();
+ should_read_new_subshell_prompt = TRUE;
+ subshell_ready = TRUE;
+ if (subshell_state == RUNNING_COMMAND)
+ {
+ subshell_state = INACTIVE;
+ return TRUE;
+ }
+ }
+
+ else if (FD_ISSET (STDIN_FILENO, &read_set))
+ /* Read from stdin, write to the subshell */
+ {
+ should_read_new_subshell_prompt = FALSE;
+ bytes = read (STDIN_FILENO, pty_buffer, sizeof (pty_buffer));
+ if (bytes <= 0)
+ {
+ tcsetattr (STDOUT_FILENO, TCSANOW, &shell_mode);
+ fprintf (stderr,
+ "read (STDIN_FILENO, pty_buffer...): %s\r\n", unix_error_string (errno));
+ exit (EXIT_FAILURE);
+ }
+
+ for (i = 0; i < bytes; ++i)
+ if (pty_buffer[i] == subshell_switch_key)
+ {
+ write_all (mc_global.tty.subshell_pty, pty_buffer, i);
+
+ if (subshell_ready)
+ {
+ subshell_state = INACTIVE;
+ set_prompt_string ();
+ if (subshell_ready && !read_command_line_buffer (FALSE))
+ {
+ /* If we got here, some unforseen error must have occurred. */
+ if (mc_global.shell->type != SHELL_FISH)
+ {
+ write_all (mc_global.tty.subshell_pty, "\003", 1);
+ subshell_state = RUNNING_COMMAND;
+ if (feed_subshell (QUIETLY, TRUE))
+ if (read_command_line_buffer (FALSE))
+ return TRUE;
+ }
+ subshell_state = ACTIVE;
+ flush_subshell (0, VISIBLY);
+ input_assign_text (cmdline, "");
+ }
+ }
+
+ return TRUE;
+ }
+
+ write_all (mc_global.tty.subshell_pty, pty_buffer, bytes);
+
+ if (pty_buffer[bytes - 1] == '\n' || pty_buffer[bytes - 1] == '\r')
+ {
+ /* We should only clear the command line if we are using a shell that works
+ * with persistent command buffer, otherwise we get awkward results. */
+ if (use_persistent_buffer)
+ input_assign_text (cmdline, "");
+ subshell_ready = FALSE;
+ }
+ }
+ else
+ return FALSE;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/* pty opening functions */
+
+#ifndef HAVE_OPENPTY
+
+#ifdef HAVE_GRANTPT
+
+/* System V version of pty_open_master */
+
+static int
+pty_open_master (char *pty_name)
+{
+ char *slave_name;
+ int pty_master;
+
+#ifdef HAVE_POSIX_OPENPT
+ pty_master = posix_openpt (O_RDWR);
+#elif defined HAVE_GETPT
+ /* getpt () is a GNU extension (glibc 2.1.x) */
+ pty_master = getpt ();
+#elif defined IS_AIX
+ strcpy (pty_name, "/dev/ptc");
+ pty_master = open (pty_name, O_RDWR);
+#else
+ strcpy (pty_name, "/dev/ptmx");
+ pty_master = open (pty_name, O_RDWR);
+#endif
+
+ if (pty_master == -1)
+ return -1;
+
+ if (grantpt (pty_master) == -1 /* Grant access to slave */
+ || unlockpt (pty_master) == -1 /* Clear slave's lock flag */
+ || !(slave_name = ptsname (pty_master))) /* Get slave's name */
+ {
+ close (pty_master);
+ return -1;
+ }
+ strcpy (pty_name, slave_name);
+ return pty_master;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/** System V version of pty_open_slave */
+
+static int
+pty_open_slave (const char *pty_name)
+{
+ int pty_slave;
+
+ pty_slave = open (pty_name, O_RDWR);
+ if (pty_slave == -1)
+ {
+ fprintf (stderr, "open (%s, O_RDWR): %s\r\n", pty_name, unix_error_string (errno));
+ return -1;
+ }
+#if !defined(__osf__) && !defined(__linux__)
+#if defined (I_FIND) && defined (I_PUSH)
+ if (ioctl (pty_slave, I_FIND, "ptem") == 0)
+ if (ioctl (pty_slave, I_PUSH, "ptem") == -1)
+ {
+ fprintf (stderr, "ioctl (%d, I_PUSH, \"ptem\") failed: %s\r\n",
+ pty_slave, unix_error_string (errno));
+ close (pty_slave);
+ return -1;
+ }
+
+ if (ioctl (pty_slave, I_FIND, "ldterm") == 0)
+ if (ioctl (pty_slave, I_PUSH, "ldterm") == -1)
+ {
+ fprintf (stderr,
+ "ioctl (%d, I_PUSH, \"ldterm\") failed: %s\r\n",
+ pty_slave, unix_error_string (errno));
+ close (pty_slave);
+ return -1;
+ }
+#if !defined(sgi) && !defined(__sgi)
+ if (ioctl (pty_slave, I_FIND, "ttcompat") == 0)
+ if (ioctl (pty_slave, I_PUSH, "ttcompat") == -1)
+ {
+ fprintf (stderr,
+ "ioctl (%d, I_PUSH, \"ttcompat\") failed: %s\r\n",
+ pty_slave, unix_error_string (errno));
+ close (pty_slave);
+ return -1;
+ }
+#endif /* sgi || __sgi */
+#endif /* I_FIND && I_PUSH */
+#endif /* __osf__ || __linux__ */
+
+ fcntl (pty_slave, F_SETFD, FD_CLOEXEC);
+ return pty_slave;
+}
+
+#else /* !HAVE_GRANTPT */
+
+/* --------------------------------------------------------------------------------------------- */
+/** BSD version of pty_open_master */
+static int
+pty_open_master (char *pty_name)
+{
+ int pty_master;
+ const char *ptr1, *ptr2;
+
+ strcpy (pty_name, "/dev/ptyXX");
+ for (ptr1 = "pqrstuvwxyzPQRST"; *ptr1; ++ptr1)
+ {
+ pty_name[8] = *ptr1;
+ for (ptr2 = "0123456789abcdef"; *ptr2 != '\0'; ++ptr2)
+ {
+ pty_name[9] = *ptr2;
+
+ /* Try to open master */
+ pty_master = open (pty_name, O_RDWR);
+ if (pty_master == -1)
+ {
+ if (errno == ENOENT) /* Different from EIO */
+ return -1; /* Out of pty devices */
+ continue; /* Try next pty device */
+ }
+ pty_name[5] = 't'; /* Change "pty" to "tty" */
+ if (access (pty_name, 6) != 0)
+ {
+ close (pty_master);
+ pty_name[5] = 'p';
+ continue;
+ }
+ return pty_master;
+ }
+ }
+ return -1; /* Ran out of pty devices */
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/** BSD version of pty_open_slave */
+
+static int
+pty_open_slave (const char *pty_name)
+{
+ int pty_slave;
+ struct group *group_info;
+
+ group_info = getgrnam ("tty");
+ if (group_info != NULL)
+ {
+ /* The following two calls will only succeed if we are root */
+ /* [Commented out while permissions problem is investigated] */
+ /* chown (pty_name, getuid (), group_info->gr_gid); FIXME */
+ /* chmod (pty_name, S_IRUSR | S_IWUSR | S_IWGRP); FIXME */
+ }
+ pty_slave = open (pty_name, O_RDWR);
+ if (pty_slave == -1)
+ fprintf (stderr, "open (pty_name, O_RDWR): %s\r\n", pty_name);
+ fcntl (pty_slave, F_SETFD, FD_CLOEXEC);
+ return pty_slave;
+}
+#endif /* !HAVE_GRANTPT */
+
+#endif /* !HAVE_OPENPTY */
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Set up `precmd' or equivalent for reading the subshell's CWD.
+ *
+ * Attention! Never forget that these are *one-liners* even though the concatenated
+ * substrings contain line breaks and indentation for better understanding of the
+ * shell code. It is vital that each one-liner ends with a line feed character ("\n" ).
+ *
+ * @return initialized pre-command string
+ */
+
+static void
+init_subshell_precmd (char *precmd, size_t buff_size)
+{
+ switch (mc_global.shell->type)
+ {
+ case SHELL_BASH:
+ g_snprintf (precmd, buff_size,
+ " mc_print_command_buffer () { printf \"%%s\\\\n\" \"$READLINE_LINE\" >&%d; }\n"
+ " bind -x '\"\\e" SHELL_BUFFER_KEYBINDING "\":\"mc_print_command_buffer\"'\n"
+ " bind -x '\"\\e" SHELL_CURSOR_KEYBINDING
+ "\":\"echo $BASH_VERSINFO:$READLINE_POINT >&%d\"'\n"
+ " PROMPT_COMMAND=${PROMPT_COMMAND:+$PROMPT_COMMAND\n}'pwd>&%d;kill -STOP $$'\n"
+ "PS1='\\u@\\h:\\w\\$ '\n", command_buffer_pipe[WRITE],
+ command_buffer_pipe[WRITE], subshell_pipe[WRITE]);
+ break;
+
+ case SHELL_ASH_BUSYBOX:
+ /* BusyBox ash needs a somewhat complicated precmd emulation via PS1, and it is vital
+ * that BB be built with active CONFIG_ASH_EXPAND_PRMT, but this is the default anyway.
+ *
+ * A: This leads to a stopped subshell (=frozen mc) if user calls "ash" command
+ * "PS1='$(pwd>&%d; kill -STOP $$)\\u@\\h:\\w\\$ '\n",
+ *
+ * B: This leads to "sh: precmd: not found" in sub-subshell if user calls "ash" command
+ * "precmd() { pwd>&%d; kill -STOP $$; }; "
+ * "PS1='$(precmd)\\u@\\h:\\w\\$ '\n",
+ *
+ * C: This works if user calls "ash" command because in sub-subshell
+ * PRECMD is undefined, thus evaluated to empty string - no damage done.
+ * Attention: BusyBox must be built with FEATURE_EDITING_FANCY_PROMPT to
+ * permit \u, \w, \h, \$ escape sequences. Unfortunately this cannot be guaranteed,
+ * especially on embedded systems where people try to save space, so let's use
+ * the dash version below. It should work on virtually all systems.
+ * "precmd() { pwd>&%d; kill -STOP $$; }; "
+ * "PRECMD=precmd; "
+ * "PS1='$(eval $PRECMD)\\u@\\h:\\w\\$ '\n",
+ */
+ case SHELL_DASH:
+ /* Debian ash needs a precmd emulation via PS1, similar to BusyBox ash,
+ * but does not support escape sequences for user, host and cwd in prompt.
+ * Attention! Make sure that the buffer for precmd is big enough.
+ *
+ * We want to have a fancy dynamic prompt with user@host:cwd just like in the BusyBox
+ * examples above, but because replacing the home directory part of the path by "~" is
+ * complicated, it bloats the precmd to a size > BUF_SMALL (128).
+ *
+ * The following example is a little less fancy (home directory not replaced)
+ * and shows the basic workings of our prompt for easier understanding:
+ *
+ * "precmd() { "
+ * "echo \"$USER@$(hostname -s):$PWD\"; "
+ * "pwd>&%d; "
+ * "kill -STOP $$; "
+ * "}; "
+ * "PRECMD=precmd; "
+ * "PS1='$($PRECMD)$ '\n",
+ */
+ g_snprintf (precmd, buff_size,
+ "precmd() { "
+ "if [ ! \"${PWD##$HOME}\" ]; then "
+ "MC_PWD=\"~\"; "
+ "else "
+ "[ \"${PWD##$HOME/}\" = \"$PWD\" ] && MC_PWD=\"$PWD\" || MC_PWD=\"~/${PWD##$HOME/}\"; "
+ "fi; "
+ "echo \"$USER@$(hostname -s):$MC_PWD\"; "
+ "pwd>&%d; "
+ "kill -STOP $$; "
+ "}; " "PRECMD=precmd; " "PS1='$($PRECMD)$ '\n", subshell_pipe[WRITE]);
+ break;
+
+ case SHELL_ZSH:
+ g_snprintf (precmd, buff_size,
+ " mc_print_command_buffer () { printf \"%%s\\\\n\" \"$BUFFER\" >&%d; }\n"
+ " zle -N mc_print_command_buffer\n"
+ " bindkey '^[" SHELL_BUFFER_KEYBINDING "' mc_print_command_buffer\n"
+ " mc_print_cursor_position () { echo $CURSOR >&%d}\n"
+ " zle -N mc_print_cursor_position\n"
+ " bindkey '^[" SHELL_CURSOR_KEYBINDING "' mc_print_cursor_position\n"
+ " _mc_precmd(){ pwd>&%d;kill -STOP $$ }; precmd_functions+=(_mc_precmd)\n"
+ "PS1='%%n@%%m:%%~%%# '\n",
+ command_buffer_pipe[WRITE], command_buffer_pipe[WRITE], subshell_pipe[WRITE]);
+ break;
+
+ case SHELL_TCSH:
+ g_snprintf (precmd, buff_size,
+ "set echo_style=both; "
+ "set prompt='%%n@%%m:%%~%%# '; "
+ "alias precmd 'echo -n;echo $cwd:q >>%s; kill -STOP $$'\n", tcsh_fifo);
+ break;
+ case SHELL_FISH:
+ g_snprintf (precmd, buff_size,
+ " bind \\e" SHELL_BUFFER_KEYBINDING " 'commandline >&%d';"
+ "bind \\e" SHELL_CURSOR_KEYBINDING " 'commandline -C >&%d';"
+ "if not functions -q fish_prompt_mc;"
+ "functions -e fish_right_prompt;"
+ "functions -c fish_prompt fish_prompt_mc; end;"
+ "function fish_prompt;"
+ "echo \"$PWD\">&%d; fish_prompt_mc; kill -STOP %%self; end\n",
+ command_buffer_pipe[WRITE], command_buffer_pipe[WRITE], subshell_pipe[WRITE]);
+ break;
+
+ default:
+ break;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Carefully quote directory name to allow entering any directory safely,
+ * no matter what weird characters it may contain in its name.
+ * NOTE: Treat directory name an untrusted data, don't allow it to cause
+ * executing any commands in the shell. Escape all control characters.
+ * Use following technique:
+ *
+ * printf(1) with format string containing a single conversion specifier,
+ * "b", and an argument which contains a copy of the string passed to
+ * subshell_name_quote() with all characters, except digits and letters,
+ * replaced by the backslash-escape sequence \0nnn, where "nnn" is the
+ * numeric value of the character converted to octal number.
+ *
+ * cd "`printf '%b' 'ABC\0nnnDEF\0nnnXYZ'`"
+ *
+ * N.B.: Use single quotes for conversion specifier to work around
+ * tcsh 6.20+ parser breakage, see ticket #3852 for the details.
+ */
+
+static GString *
+subshell_name_quote (const char *s)
+{
+ GString *ret;
+ const char *su, *n;
+ const char *quote_cmd_start, *quote_cmd_end;
+
+ if (mc_global.shell->type == SHELL_FISH)
+ {
+ quote_cmd_start = "(printf '%b' '";
+ quote_cmd_end = "')";
+ }
+ /* TODO: When BusyBox printf is fixed, get rid of this "else if", see
+ http://lists.busybox.net/pipermail/busybox/2012-March/077460.html */
+ /* else if (subshell_type == ASH_BUSYBOX)
+ {
+ quote_cmd_start = "\"`echo -en '";
+ quote_cmd_end = "'`\"";
+ } */
+ else
+ {
+ quote_cmd_start = "\"`printf '%b' '";
+ quote_cmd_end = "'`\"";
+ }
+
+ ret = g_string_sized_new (64);
+
+ /* Prevent interpreting leading '-' as a switch for 'cd' */
+ if (s[0] == '-')
+ g_string_append (ret, "./");
+
+ /* Copy the beginning of the command to the buffer */
+ g_string_append (ret, quote_cmd_start);
+
+ /*
+ * Print every character except digits and letters as a backslash-escape
+ * sequence of the form \0nnn, where "nnn" is the numeric value of the
+ * character converted to octal number.
+ */
+ for (su = s; su[0] != '\0'; su = n)
+ {
+ n = str_cget_next_char_safe (su);
+
+ if (str_isalnum (su))
+ g_string_append_len (ret, su, n - su);
+ else
+ {
+ int c;
+
+ for (c = 0; c < n - su; c++)
+ g_string_append_printf (ret, "\\0%03o", (unsigned char) su[c]);
+ }
+ }
+
+ g_string_append (ret, quote_cmd_end);
+
+ return ret;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * This function checks the pipe from which we receive data about the current working directory.
+ * If there is any data waiting, we clear it.
+ */
+
+static void
+clear_cwd_pipe (void)
+{
+ fd_set read_set;
+ struct timeval wtime = { 0, 0 };
+ int maxfdp;
+
+ FD_ZERO (&read_set);
+ FD_SET (subshell_pipe[READ], &read_set);
+ maxfdp = subshell_pipe[READ];
+
+ if (select (maxfdp + 1, &read_set, NULL, NULL, &wtime) > 0
+ && FD_ISSET (subshell_pipe[READ], &read_set))
+ {
+ if (read (subshell_pipe[READ], subshell_cwd, sizeof (subshell_cwd)) <= 0)
+ {
+ tcsetattr (STDOUT_FILENO, TCSANOW, &shell_mode);
+ fprintf (stderr, "read (subshell_pipe[READ]...): %s\r\n", unix_error_string (errno));
+ exit (EXIT_FAILURE);
+ }
+
+ synchronize ();
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Fork the subshell, and set up many, many things.
+ *
+ * Possibly modifies the global variables:
+ * subshell_type, subshell_alive, subshell_stopped, subshell_pid
+ * mc_global.tty.use_subshell - Is set to FALSE if we can't run the subshell
+ * quit - Can be set to SUBSHELL_EXIT by the SIGCHLD handler
+ */
+
+void
+init_subshell (void)
+{
+ /* This must be remembered across calls to init_subshell() */
+ static char pty_name[BUF_SMALL];
+ /* Must be considerably longer than BUF_SMALL (128) to support fancy shell prompts */
+ char precmd[BUF_MEDIUM];
+
+ /* Take the current (hopefully pristine) tty mode and make */
+ /* a raw mode based on it now, before we do anything else with it */
+ init_raw_mode ();
+
+ if (mc_global.tty.subshell_pty == 0)
+ { /* First time through */
+ if (mc_global.shell->type == SHELL_NONE)
+ return;
+
+ /* Open a pty for talking to the subshell */
+
+ /* FIXME: We may need to open a fresh pty each time on SVR4 */
+
+#ifdef HAVE_OPENPTY
+ if (openpty (&mc_global.tty.subshell_pty, &subshell_pty_slave, NULL, NULL, NULL))
+ {
+ fprintf (stderr, "Cannot open master and slave sides of pty: %s\n",
+ unix_error_string (errno));
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+#else
+ mc_global.tty.subshell_pty = pty_open_master (pty_name);
+ if (mc_global.tty.subshell_pty == -1)
+ {
+ fprintf (stderr, "Cannot open master side of pty: %s\r\n", unix_error_string (errno));
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+ subshell_pty_slave = pty_open_slave (pty_name);
+ if (subshell_pty_slave == -1)
+ {
+ fprintf (stderr, "Cannot open slave side of pty %s: %s\r\n",
+ pty_name, unix_error_string (errno));
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+#endif /* HAVE_OPENPTY */
+
+ /* Create a pipe for receiving the subshell's CWD */
+
+ if (mc_global.shell->type == SHELL_TCSH)
+ {
+ g_snprintf (tcsh_fifo, sizeof (tcsh_fifo), "%s/mc.pipe.%d",
+ mc_tmpdir (), (int) getpid ());
+ if (mkfifo (tcsh_fifo, 0600) == -1)
+ {
+ fprintf (stderr, "mkfifo(%s) failed: %s\r\n", tcsh_fifo, unix_error_string (errno));
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+
+ /* Opening the FIFO as O_RDONLY or O_WRONLY causes deadlock */
+
+ if ((subshell_pipe[READ] = open (tcsh_fifo, O_RDWR)) == -1
+ || (subshell_pipe[WRITE] = open (tcsh_fifo, O_RDWR)) == -1)
+ {
+ fprintf (stderr, _("Cannot open named pipe %s\n"), tcsh_fifo);
+ perror (__FILE__ ": open");
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+ }
+ else if (pipe (subshell_pipe) != 0) /* subshell_type is BASH, ASH_BUSYBOX, DASH or ZSH */
+ {
+ perror (__FILE__ ": couldn't create pipe");
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+
+ if (mc_global.mc_run_mode == MC_RUN_FULL &&
+ (mc_global.shell->type == SHELL_BASH || mc_global.shell->type == SHELL_ZSH
+ || mc_global.shell->type == SHELL_FISH))
+ use_persistent_buffer = TRUE;
+ if (use_persistent_buffer && pipe (command_buffer_pipe) != 0)
+ {
+ perror (__FILE__ ": couldn't create pipe");
+ mc_global.tty.use_subshell = FALSE;
+ return;
+ }
+ }
+
+ /* Fork the subshell */
+
+ subshell_alive = TRUE;
+ subshell_stopped = FALSE;
+ subshell_pid = fork ();
+
+ if (subshell_pid == -1)
+ {
+ fprintf (stderr, "Cannot spawn the subshell process: %s\r\n", unix_error_string (errno));
+ /* We exit here because, if the process table is full, the */
+ /* other method of running user commands won't work either */
+ exit (EXIT_FAILURE);
+ }
+
+ if (subshell_pid == 0)
+ {
+ /* We are in the child process */
+ init_subshell_child (pty_name);
+ }
+
+ init_subshell_precmd (precmd, BUF_MEDIUM);
+
+ write_all (mc_global.tty.subshell_pty, precmd, strlen (precmd));
+
+ /* Wait until the subshell has started up and processed the command */
+
+ subshell_state = RUNNING_COMMAND;
+ tty_enable_interrupt_key ();
+ if (!feed_subshell (QUIETLY, TRUE))
+ mc_global.tty.use_subshell = FALSE;
+ tty_disable_interrupt_key ();
+ if (!subshell_alive)
+ mc_global.tty.use_subshell = FALSE; /* Subshell died instantly, so don't use it */
+
+ /* Try out the persistent command buffer feature. If it doesn't work the first time, we
+ * assume there must be something wrong with the shell, and we turn persistent buffer off
+ * for good. This will save the user the trouble of having to wait for the persistent
+ * buffer function to time out every time they try to close the subshell. */
+ if (use_persistent_buffer && !read_command_line_buffer (TRUE))
+ use_persistent_buffer = FALSE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+int
+invoke_subshell (const char *command, int how, vfs_path_t ** new_dir_vpath)
+{
+ /* Make the MC terminal transparent */
+ tcsetattr (STDOUT_FILENO, TCSANOW, &raw_mode);
+
+ /* Make the subshell change to MC's working directory */
+ if (new_dir_vpath != NULL)
+ do_subshell_chdir (subshell_get_cwd (), TRUE);
+
+ if (command == NULL) /* The user has done "C-o" from MC */
+ {
+ if (subshell_state == INACTIVE)
+ {
+ subshell_state = ACTIVE;
+
+ /* FIXME: possibly take out this hack; the user can re-play it by hitting C-hyphen a few times! */
+ if (subshell_ready && mc_global.mc_run_mode == MC_RUN_FULL)
+ write_all (mc_global.tty.subshell_pty, " \b", 2); /* Hack to make prompt reappear */
+
+ if (use_persistent_buffer)
+ {
+ const char *s;
+ size_t i;
+ int pos;
+
+ s = input_get_ctext (cmdline);
+
+ /* Check to make sure there are no non text characters in the command buffer,
+ * such as tab, or newline, as this could cause problems. */
+ for (i = 0; i < cmdline->buffer->len; i++)
+ if ((unsigned char) s[i] < 32 || (unsigned char) s[i] == 127)
+ g_string_overwrite_len (cmdline->buffer, i, " ", 1);
+
+ /* Write the command buffer to the subshell. */
+ write_all (mc_global.tty.subshell_pty, s, cmdline->buffer->len);
+
+ /* Put the cursor in the correct place in the subshell. */
+ pos = str_length (s) - cmdline->point;
+ for (i = 0; i < (size_t) pos; i++)
+ write_all (mc_global.tty.subshell_pty, ESC_STR "[D", 3);
+ }
+ }
+ }
+ else /* MC has passed us a user command */
+ {
+ /* Before we write to the command prompt, we need to clear whatever */
+ /* data is there, but only if we are using one of the shells that */
+ /* doesn't support keeping command buffer contents, OR if there was */
+ /* some sort of error. */
+ if (use_persistent_buffer)
+ clear_cwd_pipe ();
+ else
+ {
+ /* We don't need to call feed_subshell here if we are using fish, because of a
+ * quirk in the behavior of that particular shell. */
+ if (mc_global.shell->type != SHELL_FISH)
+ {
+ write_all (mc_global.tty.subshell_pty, "\003", 1);
+ subshell_state = RUNNING_COMMAND;
+ feed_subshell (QUIETLY, FALSE);
+ }
+ }
+
+ if (how == QUIETLY)
+ write_all (mc_global.tty.subshell_pty, " ", 1);
+ /* FIXME: if command is long (>8KB ?) we go comma */
+ write_all (mc_global.tty.subshell_pty, command, strlen (command));
+ write_all (mc_global.tty.subshell_pty, "\n", 1);
+ subshell_state = RUNNING_COMMAND;
+ subshell_ready = FALSE;
+ }
+
+ feed_subshell (how, FALSE);
+
+ if (new_dir_vpath != NULL && subshell_alive)
+ {
+ const char *pcwd;
+
+ pcwd = vfs_translate_path (vfs_path_as_str (subshell_get_cwd ()));
+ if (strcmp (subshell_cwd, pcwd) != 0)
+ *new_dir_vpath = vfs_path_from_str (subshell_cwd); /* Make MC change to the subshell's CWD */
+ }
+
+ /* Restart the subshell if it has died by SIGHUP, SIGQUIT, etc. */
+ while (!subshell_alive && subshell_get_mainloop_quit () == 0 && mc_global.tty.use_subshell)
+ init_subshell ();
+
+ return subshell_get_mainloop_quit ();
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+gboolean
+flush_subshell (int max_wait_length, int how)
+{
+ int rc = 0;
+ ssize_t bytes = 0;
+ struct timeval timeleft = { 0, 0 };
+ gboolean return_value = FALSE;
+ fd_set tmp;
+
+ timeleft.tv_sec = max_wait_length;
+ FD_ZERO (&tmp);
+ FD_SET (mc_global.tty.subshell_pty, &tmp);
+
+ while (subshell_alive
+ && (rc = select (mc_global.tty.subshell_pty + 1, &tmp, NULL, NULL, &timeleft)) != 0)
+ {
+ /* Check for 'select' errors */
+ if (rc == -1)
+ {
+ if (errno == EINTR)
+ {
+ if (tty_got_winch ())
+ tty_change_screen_size ();
+
+ continue;
+ }
+
+ fprintf (stderr, "select (FD_SETSIZE, &tmp...): %s\r\n", unix_error_string (errno));
+ exit (EXIT_FAILURE);
+ }
+
+ return_value = TRUE;
+ timeleft.tv_sec = 0;
+ timeleft.tv_usec = 0;
+
+ bytes = read (mc_global.tty.subshell_pty, pty_buffer, sizeof (pty_buffer));
+ if (how == VISIBLY)
+ write_all (STDOUT_FILENO, pty_buffer, bytes);
+ }
+
+ return return_value;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+gboolean
+read_subshell_prompt (void)
+{
+ int rc = 0;
+ ssize_t bytes = 0;
+ struct timeval timeleft = { 0, 0 };
+ gboolean should_reset_prompt = TRUE;
+ gboolean got_new_prompt = FALSE;
+
+ fd_set tmp;
+ FD_ZERO (&tmp);
+ FD_SET (mc_global.tty.subshell_pty, &tmp);
+
+ while (subshell_alive
+ && (rc = select (mc_global.tty.subshell_pty + 1, &tmp, NULL, NULL, &timeleft)) != 0)
+ {
+ /* Check for 'select' errors */
+ if (rc == -1)
+ {
+ if (errno == EINTR)
+ {
+ if (tty_got_winch ())
+ tty_change_screen_size ();
+
+ continue;
+ }
+
+ fprintf (stderr, "select (FD_SETSIZE, &tmp...): %s\r\n", unix_error_string (errno));
+ exit (EXIT_FAILURE);
+ }
+
+ bytes = read (mc_global.tty.subshell_pty, pty_buffer, sizeof (pty_buffer));
+ if (should_reset_prompt)
+ {
+ should_reset_prompt = FALSE;
+ clear_subshell_prompt_string ();
+ }
+
+ parse_subshell_prompt_string (pty_buffer, bytes);
+ got_new_prompt = TRUE;
+ }
+
+ if (got_new_prompt)
+ set_prompt_string ();
+
+ return (rc != 0 || bytes != 0);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+do_update_prompt (void)
+{
+ if (update_subshell_prompt)
+ {
+ if (subshell_prompt != NULL)
+ {
+ printf ("\r\n%s", subshell_prompt->str);
+ fflush (stdout);
+ }
+ update_subshell_prompt = FALSE;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+gboolean
+exit_subshell (void)
+{
+ gboolean subshell_quit = TRUE;
+
+ if (subshell_state != INACTIVE && subshell_alive)
+ subshell_quit =
+ query_dialog (_("Warning"),
+ _("The shell is still active. Quit anyway?"),
+ D_NORMAL, 2, _("&Yes"), _("&No")) == 0;
+
+ if (subshell_quit)
+ {
+ if (mc_global.shell->type == SHELL_TCSH)
+ {
+ if (unlink (tcsh_fifo) == -1)
+ fprintf (stderr, "Cannot remove named pipe %s: %s\r\n",
+ tcsh_fifo, unix_error_string (errno));
+ }
+
+ if (subshell_prompt != NULL)
+ {
+ g_string_free (subshell_prompt, TRUE);
+ subshell_prompt = NULL;
+ }
+
+ if (subshell_prompt_temp_buffer != NULL)
+ {
+ g_string_free (subshell_prompt_temp_buffer, TRUE);
+ subshell_prompt_temp_buffer = NULL;
+ }
+
+ pty_buffer[0] = '\0';
+ }
+
+ return subshell_quit;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+/** If it actually changed the directory it returns true */
+void
+do_subshell_chdir (const vfs_path_t * vpath, gboolean update_prompt)
+{
+ char *pcwd;
+
+ pcwd = vfs_path_to_str_flags (subshell_get_cwd (), 0, VPF_RECODE);
+
+ if (!(subshell_state == INACTIVE && strcmp (subshell_cwd, pcwd) != 0))
+ {
+ /* We have to repaint the subshell prompt if we read it from
+ * the main program. Please note that in the code after this
+ * if, the cd command that is sent will make the subshell
+ * repaint the prompt, so we don't have to paint it. */
+ if (update_prompt)
+ do_update_prompt ();
+ g_free (pcwd);
+ return;
+ }
+
+ /* If we are using a shell that doesn't support persistent command buffer, we need to clear
+ * the command prompt before we send the cd command. */
+ if (!use_persistent_buffer)
+ {
+ write_all (mc_global.tty.subshell_pty, "\003", 1);
+ subshell_state = RUNNING_COMMAND;
+ if (mc_global.shell->type != SHELL_FISH)
+ if (!feed_subshell (QUIETLY, TRUE))
+ {
+ subshell_state = ACTIVE;
+ return;
+ }
+ }
+ /* The initial space keeps this out of the command history (in bash
+ because we set "HISTCONTROL=ignorespace") */
+ write_all (mc_global.tty.subshell_pty, " cd ", 4);
+
+ if (vpath != NULL)
+ {
+ const char *translate;
+
+ translate = vfs_translate_path (vfs_path_as_str (vpath));
+ if (translate != NULL)
+ {
+ GString *temp;
+
+ temp = subshell_name_quote (translate);
+ write_all (mc_global.tty.subshell_pty, temp->str, temp->len);
+ g_string_free (temp, TRUE);
+ }
+ else
+ {
+ write_all (mc_global.tty.subshell_pty, ".", 1);
+ }
+ }
+ else
+ {
+ write_all (mc_global.tty.subshell_pty, "/", 1);
+ }
+ write_all (mc_global.tty.subshell_pty, "\n", 1);
+
+ subshell_state = RUNNING_COMMAND;
+ if (!feed_subshell (QUIETLY, TRUE))
+ {
+ subshell_state = ACTIVE;
+ return;
+ }
+
+ if (subshell_alive)
+ {
+ gboolean bPathNotEq;
+
+ bPathNotEq = strcmp (subshell_cwd, pcwd) != 0;
+
+ if (bPathNotEq && mc_global.shell->type == SHELL_TCSH)
+ {
+ char rp_subshell_cwd[PATH_MAX];
+ char rp_current_panel_cwd[PATH_MAX];
+ char *p_subshell_cwd, *p_current_panel_cwd;
+
+ p_subshell_cwd = mc_realpath (subshell_cwd, rp_subshell_cwd);
+ p_current_panel_cwd = mc_realpath (pcwd, rp_current_panel_cwd);
+
+ if (p_subshell_cwd == NULL)
+ p_subshell_cwd = subshell_cwd;
+ if (p_current_panel_cwd == NULL)
+ p_current_panel_cwd = pcwd;
+ bPathNotEq = strcmp (p_subshell_cwd, p_current_panel_cwd) != 0;
+ }
+
+ if (bPathNotEq && !DIR_IS_DOT (pcwd))
+ {
+ char *cwd;
+
+ cwd = vfs_path_to_str_flags (subshell_get_cwd (), 0, VPF_STRIP_PASSWORD);
+ vfs_print_message (_("Warning: Cannot change to %s.\n"), cwd);
+ g_free (cwd);
+ }
+ }
+
+ /* Really escape Zsh history */
+ if (mc_global.shell->type == SHELL_ZSH)
+ {
+ /* Per Zsh documentation last command prefixed with space lingers in the internal history
+ * until the next command is entered before it vanishes. To make it vanish right away,
+ * type a space and press return. */
+ write_all (mc_global.tty.subshell_pty, " \n", 2);
+ subshell_state = RUNNING_COMMAND;
+ feed_subshell (QUIETLY, TRUE);
+ }
+
+ update_subshell_prompt = FALSE;
+
+ g_free (pcwd);
+ /* Make sure that MC never stores the CWD in a silly format */
+ /* like /usr////lib/../bin, or the strcmp() above will fail */
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+subshell_get_console_attributes (void)
+{
+ /* Get our current terminal modes */
+
+ if (tcgetattr (STDOUT_FILENO, &shell_mode))
+ {
+ fprintf (stderr, "Cannot get terminal settings: %s\r\n", unix_error_string (errno));
+ mc_global.tty.use_subshell = FALSE;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Figure out whether the subshell has stopped, exited or been killed
+ * Possibly modifies: 'subshell_alive', 'subshell_stopped' and 'quit' */
+
+void
+sigchld_handler (int sig)
+{
+ int status;
+ pid_t pid;
+
+ (void) sig;
+
+ pid = waitpid (subshell_pid, &status, WUNTRACED | WNOHANG);
+
+ if (pid == subshell_pid)
+ {
+ /* Figure out what has happened to the subshell */
+
+ if (WIFSTOPPED (status))
+ {
+ if (WSTOPSIG (status) == SIGSTOP)
+ {
+ /* The subshell has received a SIGSTOP signal */
+ subshell_stopped = TRUE;
+ }
+ else
+ {
+ /* The user has suspended the subshell. Revive it */
+ kill (subshell_pid, SIGCONT);
+ }
+ }
+ else
+ {
+ /* The subshell has either exited normally or been killed */
+ subshell_alive = FALSE;
+ delete_select_channel (mc_global.tty.subshell_pty);
+ if (WIFEXITED (status) && WEXITSTATUS (status) != FORK_FAILURE)
+ {
+ int subshell_quit;
+ subshell_quit = subshell_get_mainloop_quit () | SUBSHELL_EXIT; /* Exited normally */
+ subshell_set_mainloop_quit (subshell_quit);
+ }
+ }
+ }
+ subshell_handle_cons_saver ();
+
+ /* If we got here, some other child exited; ignore it */
+}
+
+/* --------------------------------------------------------------------------------------------- */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-29 17:06:58 +0000