src/main.c

   1 /*
   2    Main program for the Midnight Commander
   3
   4    Copyright (C) 1994-2024
   5    Free Software Foundation, Inc.
   6
   7    Written by:
   8    Miguel de Icaza, 1994, 1995, 1996, 1997
   9    Janne Kukonlehto, 1994, 1995
  10    Norbert Warmuth, 1997
  11
  12    This file is part of the Midnight Commander.
  13
  14    The Midnight Commander is free software: you can redistribute it
  15    and/or modify it under the terms of the GNU General Public License as
  16    published by the Free Software Foundation, either version 3 of the License,
  17    or (at your option) any later version.
  18
  19    The Midnight Commander is distributed in the hope that it will be useful,
  20    but WITHOUT ANY WARRANTY; without even the implied warranty of
  21    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22    GNU General Public License for more details.
  23
  24    You should have received a copy of the GNU General Public License
  25    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  26  */
  27
  28 /** \file main.c
  29  *  \brief Source: this is a main module
  30  */
  31
  32 #include <config.h>
  33
  34 #include <ctype.h>
  35 #include <errno.h>
  36 #include <locale.h>
  37 #include <pwd.h>                /* for username in xterm title */
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <sys/types.h>
  42 #include <sys/wait.h>
  43 #include <signal.h>
  44 #include <unistd.h>             /* getsid() */
  45
  46 #include "lib/global.h"
  47
  48 #include "lib/event.h"
  49 #include "lib/tty/tty.h"
  50 #include "lib/tty/key.h"        /* For init_key() */
  51 #include "lib/tty/mouse.h"      /* init_mouse() */
  52 #include "lib/skin.h"
  53 #include "lib/filehighlight.h"
  54 #include "lib/fileloc.h"
  55 #include "lib/strutil.h"
  56 #include "lib/util.h"
  57 #include "lib/vfs/vfs.h"        /* vfs_init(), vfs_shut() */
  58
  59 #include "filemanager/filemanager.h"
  60 #include "filemanager/treestore.h"      /* tree_store_save */
  61 #include "filemanager/layout.h"
  62 #include "filemanager/ext.h"    /* flush_extension_file() */
  63 #include "filemanager/command.h"        /* cmdline */
  64 #include "filemanager/panel.h"  /* panalized_panel */
  65
  66 #include "vfs/plugins_init.h"
  67
  68 #include "events_init.h"
  69 #include "args.h"
  70 #ifdef ENABLE_SUBSHELL
  71 #include "subshell/subshell.h"
  72 #endif
  73 #include "keymap.h"
  74 #include "setup.h"              /* load_setup() */
  75
  76 #ifdef HAVE_CHARSET
  77 #include "lib/charsets.h"
  78 #include "selcodepage.h"
  79 #endif /* HAVE_CHARSET */
  80
  81 #include "consaver/cons.saver.h"        /* cons_saver_pid */
  82
  83 /*** global variables ****************************************************************************/
  84
  85 /*** file scope macro definitions ****************************************************************/
  86
  87 /*** file scope type declarations ****************************************************************/
  88
  89 /*** forward declarations (file scope functions) *************************************************/
  90
  91 /*** file scope variables ************************************************************************/
  92
  93 /* --------------------------------------------------------------------------------------------- */
  94 /*** file scope functions ************************************************************************/
  95 /* --------------------------------------------------------------------------------------------- */
  96
  97 static void
  98 check_codeset (void)
  99 {
 100     const char *current_system_codepage = NULL;
 101
 102     current_system_codepage = str_detect_termencoding ();
 103
 104 #ifdef HAVE_CHARSET
 105     {
 106         const char *_display_codepage;
 107
 108         _display_codepage = get_codepage_id (mc_global.display_codepage);
 109
 110         if (strcmp (_display_codepage, current_system_codepage) != 0)
 111         {
 112             mc_global.display_codepage = get_codepage_index (current_system_codepage);
 113             if (mc_global.display_codepage == -1)
 114                 mc_global.display_codepage = 0;
 115
 116             mc_config_set_string (mc_global.main_config, CONFIG_MISC_SECTION, "display_codepage",
 117                                   cp_display);
 118         }
 119     }
 120 #endif
 121
 122     mc_global.utf8_display = str_isutf8 (current_system_codepage);
 123 }
 124
 125 /* --------------------------------------------------------------------------------------------- */
 126 /** POSIX version.  The only version we support.  */
 127
 128 static void
 129 OS_Setup (void)
 130 {
 131     const char *datadir_env;
 132
 133     mc_shell_init ();
 134
 135     /* This is the directory, where MC was installed, on Unix this is DATADIR */
 136     /* and can be overridden by the MC_DATADIR environment variable */
 137     datadir_env = g_getenv ("MC_DATADIR");
 138     if (datadir_env != NULL)
 139         mc_global.sysconfig_dir = g_strdup (datadir_env);
 140     else
 141         mc_global.sysconfig_dir = g_strdup (SYSCONFDIR);
 142
 143     mc_global.share_data_dir = g_strdup (DATADIR);
 144 }
 145
 146 /* --------------------------------------------------------------------------------------------- */
 147
 148 static void
 149 sigchld_handler_no_subshell (int sig)
 150 {
 151 #ifdef __linux__
 152     int pid, status;
 153
 154     if (mc_global.tty.console_flag == '\0')
 155         return;
 156
 157     /* COMMENT: if it were true that after the call to handle_console(..INIT)
 158        the value of mc_global.tty.console_flag never changed, we could simply not install
 159        this handler at all if (!mc_global.tty.console_flag && !mc_global.tty.use_subshell). */
 160
 161     /* That comment is no longer true.  We need to wait() on a sigchld
 162        handler (that's at least what the tarfs code expects currently). */
 163
 164     pid = waitpid (cons_saver_pid, &status, WUNTRACED | WNOHANG);
 165
 166     if (pid == cons_saver_pid)
 167     {
 168         if (WIFSTOPPED (status))
 169         {
 170             /* Someone has stopped cons.saver - restart it */
 171             kill (pid, SIGCONT);
 172         }
 173         else
 174         {
 175             /* cons.saver has died - disable console saving */
 176             handle_console (CONSOLE_DONE);
 177             mc_global.tty.console_flag = '\0';
 178         }
 179     }
 180     /* If we got here, some other child exited; ignore it */
 181 #endif /* __linux__ */
 182
 183     (void) sig;
 184 }
 185
 186 /* --------------------------------------------------------------------------------------------- */
 187
 188 static void
 189 init_sigchld (void)
 190 {
 191     struct sigaction sigchld_action;
 192
 193     memset (&sigchld_action, 0, sizeof (sigchld_action));
 194     sigchld_action.sa_handler =
 195 #ifdef ENABLE_SUBSHELL
 196         mc_global.tty.use_subshell ? sigchld_handler :
 197 #endif /* ENABLE_SUBSHELL */
 198         sigchld_handler_no_subshell;
 199
 200     sigemptyset (&sigchld_action.sa_mask);
 201
 202 #ifdef SA_RESTART
 203     sigchld_action.sa_flags = SA_RESTART;
 204 #endif /* !SA_RESTART */
 205
 206     if (sigaction (SIGCHLD, &sigchld_action, NULL) == -1)
 207     {
 208 #ifdef ENABLE_SUBSHELL
 209         /*
 210          * This may happen on QNX Neutrino 6, where SA_RESTART
 211          * is defined but not implemented.  Fallback to no subshell.
 212          */
 213         mc_global.tty.use_subshell = FALSE;
 214 #endif /* ENABLE_SUBSHELL */
 215     }
 216 }
 217
 218 /* --------------------------------------------------------------------------------------------- */
 219 /**
 220  * Check MC_SID to prevent running one mc from another.
 221  *
 222  * @return TRUE if no parent mc in our session was found, FALSE otherwise.
 223  */
 224
 225 static gboolean
 226 check_sid (void)
 227 {
 228     pid_t my_sid, old_sid;
 229     const char *sid_str;
 230
 231     sid_str = getenv ("MC_SID");
 232     if (sid_str == NULL)
 233         return TRUE;
 234
 235     old_sid = (pid_t) strtol (sid_str, NULL, 0);
 236     if (old_sid == 0)
 237         return TRUE;
 238
 239     my_sid = getsid (0);
 240     if (my_sid == -1)
 241         return TRUE;
 242
 243     /* The parent mc is in a different session, it's OK */
 244     return (old_sid != my_sid);
 245 }
 246
 247 /* --------------------------------------------------------------------------------------------- */
 248 /*** public functions ****************************************************************************/
 249 /* --------------------------------------------------------------------------------------------- */
 250
 251 int
 252 main (int argc, char *argv[])
 253 {
 254     GError *mcerror = NULL;
 255     int exit_code = EXIT_FAILURE;
 256
 257     mc_global.run_from_parent_mc = !check_sid ();
 258
 259     /* We had LC_CTYPE before, LC_ALL includs LC_TYPE as well */
 260 #ifdef HAVE_SETLOCALE
 261     (void) setlocale (LC_ALL, "");
 262 #endif
 263     (void) bindtextdomain (PACKAGE, LOCALEDIR);
 264     (void) textdomain (PACKAGE);
 265
 266     /* do this before args parsing */
 267     str_init_strings (NULL);
 268
 269     mc_setup_run_mode (argv);   /* are we mc? editor? viewer? etc... */
 270
 271     if (!mc_args_parse (&argc, &argv, "mc", &mcerror))
 272     {
 273       startup_exit_falure:
 274         fprintf (stderr, _("Failed to run:\n%s\n"), mcerror->message);
 275         g_error_free (mcerror);
 276       startup_exit_ok:
 277         mc_shell_deinit ();
 278         str_uninit_strings ();
 279         return exit_code;
 280     }
 281
 282     /* check terminal type
 283      * $TERM must be set and not empty
 284      * mc_global.tty.xterm_flag is used in init_key() and tty_init()
 285      * Do this after mc_args_parse() where mc_args__force_xterm is set up.
 286      */
 287     mc_global.tty.xterm_flag = tty_check_term (mc_args__force_xterm);
 288
 289     /* do this before mc_args_show_info () to view paths in the --datadir-info output */
 290     OS_Setup ();
 291
 292     if (!g_path_is_absolute (mc_config_get_home_dir ()))
 293     {
 294         mc_propagate_error (&mcerror, 0, "%s: %s", _("Home directory path is not absolute"),
 295                             mc_config_get_home_dir ());
 296         mc_event_deinit (NULL);
 297         goto startup_exit_falure;
 298     }
 299
 300     if (!mc_args_show_info ())
 301     {
 302         exit_code = EXIT_SUCCESS;
 303         goto startup_exit_ok;
 304     }
 305
 306     if (!events_init (&mcerror))
 307         goto startup_exit_falure;
 308
 309     mc_config_init_config_paths (&mcerror);
 310     if (mcerror != NULL)
 311     {
 312         mc_event_deinit (NULL);
 313         goto startup_exit_falure;
 314     }
 315
 316     vfs_init ();
 317     vfs_plugins_init ();
 318
 319     load_setup ();
 320
 321     /* Must be done after load_setup because depends on mc_global.vfs.cd_symlinks */
 322     vfs_setup_work_dir ();
 323
 324     /* Set up temporary directory after VFS initialization */
 325     mc_tmpdir ();
 326
 327     /* do this after vfs initialization and vfs working directory setup
 328        due to mc_setctl() and mcedit_arg_vpath_new() calls in mc_setup_by_args() */
 329     if (!mc_setup_by_args (argc, argv, &mcerror))
 330     {
 331         vfs_shut ();
 332         done_setup ();
 333         g_free (saved_other_dir);
 334         mc_event_deinit (NULL);
 335         goto startup_exit_falure;
 336     }
 337
 338     /* Resolve the other_dir panel option.
 339      * 1. Must be done after vfs_setup_work_dir().
 340      * 2. Must be done after mc_setup_by_args() because of mc_run_mode.
 341      */
 342     if (mc_global.mc_run_mode == MC_RUN_FULL)
 343     {
 344         char *buffer;
 345         vfs_path_t *vpath;
 346
 347         buffer = mc_config_get_string (mc_global.panels_config, "Dirs", "other_dir", ".");
 348         vpath = vfs_path_from_str (buffer);
 349         if (vfs_file_is_local (vpath))
 350             saved_other_dir = buffer;
 351         else
 352             g_free (buffer);
 353         vfs_path_free (vpath, TRUE);
 354     }
 355
 356     /* NOTE: This has to be called before tty_init or whatever routine
 357        calls any define_sequence */
 358     init_key ();
 359
 360     /* Must be done before installing the SIGCHLD handler [[FIXME]] */
 361     handle_console (CONSOLE_INIT);
 362
 363 #ifdef ENABLE_SUBSHELL
 364     /* Disallow subshell when invoked as standalone viewer or editor from running mc */
 365     if (mc_global.mc_run_mode != MC_RUN_FULL && mc_global.run_from_parent_mc)
 366         mc_global.tty.use_subshell = FALSE;
 367
 368     if (mc_global.tty.use_subshell)
 369         subshell_get_console_attributes ();
 370 #endif /* ENABLE_SUBSHELL */
 371
 372     /* Install the SIGCHLD handler; must be done before init_subshell() */
 373     init_sigchld ();
 374
 375     /* We need this, since ncurses endwin () doesn't restore the signals */
 376     save_stop_handler ();
 377
 378     /* Must be done before init_subshell, to set up the terminal size: */
 379     /* FIXME: Should be removed and LINES and COLS computed on subshell */
 380     tty_init (!mc_args__nomouse, mc_global.tty.xterm_flag);
 381
 382     /* start check mc_global.display_codepage and mc_global.source_codepage */
 383     check_codeset ();
 384
 385     /* Removing this from the X code let's us type C-c */
 386     load_key_defs ();
 387
 388     keymap_load (!mc_args__nokeymap);
 389
 390 #ifdef USE_INTERNAL_EDIT
 391     macros_list = g_array_new (TRUE, FALSE, sizeof (macros_t));
 392 #endif /* USE_INTERNAL_EDIT */
 393
 394     tty_init_colors (mc_global.tty.disable_colors, mc_args__force_colors);
 395
 396     mc_skin_init (NULL, &mcerror);
 397     dlg_set_default_colors ();
 398     input_set_default_colors ();
 399     if (mc_global.mc_run_mode == MC_RUN_FULL)
 400         command_set_default_colors ();
 401
 402     mc_error_message (&mcerror, NULL);
 403
 404 #ifdef ENABLE_SUBSHELL
 405     /* Done here to ensure that the subshell doesn't  */
 406     /* inherit the file descriptors opened below, etc */
 407     if (mc_global.tty.use_subshell && mc_global.run_from_parent_mc)
 408     {
 409         int r;
 410
 411         r = query_dialog (_("Warning"),
 412                           _("GNU Midnight Commander\nis already running on this terminal.\n"
 413                             "Subshell support will be disabled."),
 414                           D_ERROR, 2, _("&OK"), _("&Quit"));
 415         if (r == 0)
 416         {
 417             /* parent mc was found and the user wants to continue */
 418             ;
 419         }
 420         else
 421         {
 422             /* parent mc was found and the user wants to quit mc */
 423             mc_global.midnight_shutdown = TRUE;
 424         }
 425
 426         mc_global.tty.use_subshell = FALSE;
 427     }
 428
 429     if (mc_global.tty.use_subshell)
 430         init_subshell ();
 431 #endif /* ENABLE_SUBSHELL */
 432
 433     if (!mc_global.midnight_shutdown)
 434     {
 435         /* Also done after init_subshell, to save any shell init file messages */
 436         if (mc_global.tty.console_flag != '\0')
 437             handle_console (CONSOLE_SAVE);
 438
 439         if (mc_global.tty.alternate_plus_minus)
 440             application_keypad_mode ();
 441
 442         /* Done after subshell initialization to allow select and paste text by mouse
 443            w/o Shift button in subshell in the native console */
 444         init_mouse ();
 445
 446         /* Done after tty_enter_ca_mode (tty_init) because in VTE bracketed mode is
 447            separate for the normal and alternate screens */
 448         enable_bracketed_paste ();
 449
 450         /* subshell_prompt is NULL here */
 451         mc_prompt = (geteuid () == 0) ? "# " : "$ ";
 452     }
 453
 454     /* Program main loop */
 455     if (mc_global.midnight_shutdown)
 456         exit_code = EXIT_SUCCESS;
 457     else
 458         exit_code = do_nc ()? EXIT_SUCCESS : EXIT_FAILURE;
 459
 460     disable_bracketed_paste ();
 461
 462     disable_mouse ();
 463
 464     /* Save the tree store */
 465     (void) tree_store_save ();
 466
 467     keymap_free ();
 468
 469     /* Virtual File System shutdown */
 470     vfs_shut ();
 471
 472     flush_extension_file ();    /* does only free memory */
 473
 474     mc_skin_deinit ();
 475     tty_colors_done ();
 476
 477     tty_shutdown ();
 478
 479     done_setup ();
 480
 481     if (mc_global.tty.console_flag != '\0' && (quit & SUBSHELL_EXIT) == 0)
 482         handle_console (CONSOLE_RESTORE);
 483     if (mc_global.tty.alternate_plus_minus)
 484         numeric_keypad_mode ();
 485
 486     (void) signal (SIGCHLD, SIG_DFL);   /* Disable the SIGCHLD handler */
 487
 488     if (mc_global.tty.console_flag != '\0')
 489         handle_console (CONSOLE_DONE);
 490
 491     if (mc_global.mc_run_mode == MC_RUN_FULL && mc_args__last_wd_file != NULL
 492         && last_wd_string != NULL && !print_last_revert)
 493     {
 494         int last_wd_fd;
 495
 496         last_wd_fd = open (mc_args__last_wd_file, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL,
 497                            S_IRUSR | S_IWUSR);
 498         if (last_wd_fd != -1)
 499         {
 500             ssize_t ret1;
 501             int ret2;
 502             ret1 = write (last_wd_fd, last_wd_string, strlen (last_wd_string));
 503             ret2 = close (last_wd_fd);
 504             (void) ret1;
 505             (void) ret2;
 506         }
 507     }
 508     g_free (last_wd_string);
 509
 510     mc_shell_deinit ();
 511
 512     done_key ();
 513
 514 #ifdef USE_INTERNAL_EDIT
 515     if (macros_list != NULL)
 516     {
 517         guint i;
 518
 519         for (i = 0; i < macros_list->len; i++)
 520         {
 521             macros_t *macros;
 522
 523             macros = &g_array_index (macros_list, struct macros_t, i);
 524             if (macros != NULL && macros->macro != NULL)
 525                 (void) g_array_free (macros->macro, TRUE);
 526         }
 527         (void) g_array_free (macros_list, TRUE);
 528     }
 529 #endif /* USE_INTERNAL_EDIT */
 530
 531     str_uninit_strings ();
 532
 533     if (mc_global.mc_run_mode != MC_RUN_EDITOR)
 534         g_free (mc_run_param0);
 535     else
 536         g_list_free_full ((GList *) mc_run_param0, (GDestroyNotify) mcedit_arg_free);
 537
 538     g_free (mc_run_param1);
 539     g_free (saved_other_dir);
 540
 541     mc_config_deinit_config_paths ();
 542
 543     (void) mc_event_deinit (&mcerror);
 544     if (mcerror != NULL)
 545     {
 546         fprintf (stderr, _("\nFailed while close:\n%s\n"), mcerror->message);
 547         g_error_free (mcerror);
 548         exit_code = EXIT_FAILURE;
 549     }
 550
 551     (void) putchar ('\n');      /* Hack to make shell's prompt start at left of screen */
 552
 553     return exit_code;
 554 }
 555
 556 /* --------------------------------------------------------------------------------------------- */