gdb/tui/tui.c

   1 /* General functions for the WDB TUI.
   2
   3    Copyright (C) 1998-2019 Free Software Foundation, Inc.
   4
   5    Contributed by Hewlett-Packard Company.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "defs.h"
  23 #include "gdbcmd.h"
  24 #include "tui/tui.h"
  25 #include "tui/tui-hooks.h"
  26 #include "tui/tui-data.h"
  27 #include "tui/tui-layout.h"
  28 #include "tui/tui-io.h"
  29 #include "tui/tui-regs.h"
  30 #include "tui/tui-stack.h"
  31 #include "tui/tui-win.h"
  32 #include "tui/tui-winsource.h"
  33 #include "tui/tui-windata.h"
  34 #include "target.h"
  35 #include "frame.h"
  36 #include "breakpoint.h"
  37 #include "inferior.h"
  38 #include "symtab.h"
  39 #include "source.h"
  40 #include "terminal.h"
  41 #include "top.h"
  42
  43 #include <ctype.h>
  44 #include <signal.h>
  45 #include <fcntl.h>
  46 #if 0
  47 #include <termio.h>
  48 #endif
  49 #include <setjmp.h>
  50
  51 #include "gdb_curses.h"
  52 #include "interps.h"
  53
  54 /* This redefines CTRL if it is not already defined, so it must come
  55    after terminal state releated include files like <term.h> and
  56    "gdb_curses.h".  */
  57 #include "readline/readline.h"
  58
  59 /* Tells whether the TUI is active or not.  */
  60 int tui_active = 0;
  61 static int tui_finish_init = 1;
  62
  63 enum tui_key_mode tui_current_key_mode = TUI_COMMAND_MODE;
  64
  65 struct tui_char_command
  66 {
  67   unsigned char key;
  68   const char *cmd;
  69 };
  70
  71 /* Key mapping to gdb commands when the TUI is using the single key
  72    mode.  */
  73 static const struct tui_char_command tui_commands[] = {
  74   { 'c', "continue" },
  75   { 'd', "down" },
  76   { 'f', "finish" },
  77   { 'n', "next" },
  78   { 'o', "nexti" },
  79   { 'r', "run" },
  80   { 's', "step" },
  81   { 'i', "stepi" },
  82   { 'u', "up" },
  83   { 'v', "info locals" },
  84   { 'w', "where" },
  85   { 0, 0 },
  86 };
  87
  88 static Keymap tui_keymap;
  89 static Keymap tui_readline_standard_keymap;
  90
  91 /* TUI readline command.
  92    Switch the output mode between TUI/standard gdb.  */
  93 static int
  94 tui_rl_switch_mode (int notused1, int notused2)
  95 {
  96
  97   /* Don't let exceptions escape.  We're in the middle of a readline
  98      callback that isn't prepared for that.  */
  99   TRY
 100     {
 101       if (tui_active)
 102         {
 103           tui_disable ();
 104           rl_prep_terminal (0);
 105         }
 106       else
 107         {
 108           /* If tui_enable throws, we'll re-prep below.  */
 109           rl_deprep_terminal ();
 110           tui_enable ();
 111         }
 112     }
 113   CATCH (ex, RETURN_MASK_ALL)
 114     {
 115       exception_print (gdb_stderr, ex);
 116
 117       if (!tui_active)
 118         rl_prep_terminal (0);
 119     }
 120   END_CATCH
 121
 122   /* Clear the readline in case switching occurred in middle of
 123      something.  */
 124   if (rl_end)
 125     rl_kill_text (0, rl_end);
 126
 127   /* Since we left the curses mode, the terminal mode is restored to
 128      some previous state.  That state may not be suitable for readline
 129      to work correctly (it may be restored in line mode).  We force an
 130      exit of the current readline so that readline is re-entered and
 131      it will be able to setup the terminal for its needs.  By
 132      re-entering in readline, we also redisplay its prompt in the
 133      non-curses mode.  */
 134   rl_newline (1, '\n');
 135
 136   /* Make sure the \n we are returning does not repeat the last
 137      command.  */
 138   dont_repeat ();
 139   return 0;
 140 }
 141
 142 /* TUI readline command.
 143    Change the TUI layout to show a next layout.
 144    This function is bound to CTRL-X 2.  It is intended to provide
 145    a functionality close to the Emacs split-window command.  We
 146    always show two windows (src+asm), (src+regs) or (asm+regs).  */
 147 static int
 148 tui_rl_change_windows (int notused1, int notused2)
 149 {
 150   if (!tui_active)
 151     tui_rl_switch_mode (0 /* notused */, 0 /* notused */);
 152
 153   if (tui_active)
 154     {
 155       enum tui_layout_type new_layout;
 156
 157       new_layout = tui_current_layout ();
 158
 159       /* Select a new layout to have a rolling layout behavior with
 160          always two windows (except when undefined).  */
 161       switch (new_layout)
 162         {
 163         case SRC_COMMAND:
 164           new_layout = SRC_DISASSEM_COMMAND;
 165           break;
 166
 167         case DISASSEM_COMMAND:
 168           new_layout = SRC_DISASSEM_COMMAND;
 169           break;
 170
 171         case SRC_DATA_COMMAND:
 172           new_layout = SRC_DISASSEM_COMMAND;
 173           break;
 174
 175         case SRC_DISASSEM_COMMAND:
 176           new_layout = DISASSEM_DATA_COMMAND;
 177           break;
 178
 179         case DISASSEM_DATA_COMMAND:
 180           new_layout = SRC_DATA_COMMAND;
 181           break;
 182
 183         default:
 184           new_layout = SRC_COMMAND;
 185           break;
 186         }
 187       tui_set_layout (new_layout);
 188     }
 189   return 0;
 190 }
 191
 192 /* TUI readline command.
 193    Delete the second TUI window to only show one.  */
 194 static int
 195 tui_rl_delete_other_windows (int notused1, int notused2)
 196 {
 197   if (!tui_active)
 198     tui_rl_switch_mode (0 /* notused */, 0 /* notused */);
 199
 200   if (tui_active)
 201     {
 202       enum tui_layout_type new_layout;
 203
 204       new_layout = tui_current_layout ();
 205
 206       /* Kill one window.  */
 207       switch (new_layout)
 208         {
 209         case SRC_COMMAND:
 210         case SRC_DATA_COMMAND:
 211         case SRC_DISASSEM_COMMAND:
 212         default:
 213           new_layout = SRC_COMMAND;
 214           break;
 215
 216         case DISASSEM_COMMAND:
 217         case DISASSEM_DATA_COMMAND:
 218           new_layout = DISASSEM_COMMAND;
 219           break;
 220         }
 221       tui_set_layout (new_layout);
 222     }
 223   return 0;
 224 }
 225
 226 /* TUI readline command.
 227    Switch the active window to give the focus to a next window.  */
 228 static int
 229 tui_rl_other_window (int count, int key)
 230 {
 231   struct tui_win_info *win_info;
 232
 233   if (!tui_active)
 234     tui_rl_switch_mode (0 /* notused */, 0 /* notused */);
 235
 236   win_info = tui_next_win (tui_win_with_focus ());
 237   if (win_info)
 238     {
 239       tui_set_win_focus_to (win_info);
 240       if (TUI_DATA_WIN && TUI_DATA_WIN->generic.is_visible)
 241         tui_refresh_data_win ();
 242       keypad (TUI_CMD_WIN->generic.handle, (win_info != TUI_CMD_WIN));
 243     }
 244   return 0;
 245 }
 246
 247 /* TUI readline command.
 248    Execute the gdb command bound to the specified key.  */
 249 static int
 250 tui_rl_command_key (int count, int key)
 251 {
 252   int i;
 253
 254   reinitialize_more_filter ();
 255   for (i = 0; tui_commands[i].cmd; i++)
 256     {
 257       if (tui_commands[i].key == key)
 258         {
 259           /* Insert the command in the readline buffer.
 260              Avoid calling the gdb command here since it creates
 261              a possible recursion on readline if prompt_for_continue
 262              is called (See PR 9584).  The command will also appear
 263              in the readline history which turns out to be better.  */
 264           rl_insert_text (tui_commands[i].cmd);
 265           rl_newline (1, '\n');
 266
 267           /* Switch to gdb command mode while executing the command.
 268              This way the gdb's continue prompty will be displayed.  */
 269           tui_set_key_mode (TUI_ONE_COMMAND_MODE);
 270           return 0;
 271         }
 272     }
 273   return 0;
 274 }
 275
 276 /* TUI readline command.
 277    Temporarily leave the TUI SingleKey mode to allow editing
 278    a gdb command with the normal readline.  Once the command
 279    is executed, the TUI SingleKey mode is installed back.  */
 280 static int
 281 tui_rl_command_mode (int count, int key)
 282 {
 283   tui_set_key_mode (TUI_ONE_COMMAND_MODE);
 284   return rl_insert (count, key);
 285 }
 286
 287 /* TUI readline command.
 288    Switch between TUI SingleKey mode and gdb readline editing.  */
 289 static int
 290 tui_rl_next_keymap (int notused1, int notused2)
 291 {
 292   if (!tui_active)
 293     tui_rl_switch_mode (0 /* notused */, 0 /* notused */);
 294
 295   tui_set_key_mode (tui_current_key_mode == TUI_COMMAND_MODE
 296                     ? TUI_SINGLE_KEY_MODE : TUI_COMMAND_MODE);
 297   return 0;
 298 }
 299
 300 /* Readline hook to redisplay ourself the gdb prompt.
 301    In the SingleKey mode, the prompt is not printed so that
 302    the command window is cleaner.  It will be displayed if
 303    we temporarily leave the SingleKey mode.  */
 304 static int
 305 tui_rl_startup_hook (void)
 306 {
 307   rl_already_prompted = 1;
 308   if (tui_current_key_mode != TUI_COMMAND_MODE
 309       && !gdb_in_secondary_prompt_p (current_ui))
 310     tui_set_key_mode (TUI_SINGLE_KEY_MODE);
 311   tui_redisplay_readline ();
 312   return 0;
 313 }
 314
 315 /* Change the TUI key mode by installing the appropriate readline
 316    keymap.  */
 317 void
 318 tui_set_key_mode (enum tui_key_mode mode)
 319 {
 320   tui_current_key_mode = mode;
 321   rl_set_keymap (mode == TUI_SINGLE_KEY_MODE
 322                  ? tui_keymap : tui_readline_standard_keymap);
 323   tui_show_locator_content ();
 324 }
 325
 326 /* Initialize readline and configure the keymap for the switching
 327    key shortcut.  */
 328 void
 329 tui_initialize_readline (void)
 330 {
 331   int i;
 332   Keymap tui_ctlx_keymap;
 333
 334   rl_initialize ();
 335
 336   rl_add_defun ("tui-switch-mode", tui_rl_switch_mode, -1);
 337   rl_add_defun ("gdb-command", tui_rl_command_key, -1);
 338   rl_add_defun ("next-keymap", tui_rl_next_keymap, -1);
 339
 340   tui_keymap = rl_make_bare_keymap ();
 341   tui_ctlx_keymap = rl_make_bare_keymap ();
 342   tui_readline_standard_keymap = rl_get_keymap ();
 343
 344   for (i = 0; tui_commands[i].cmd; i++)
 345     rl_bind_key_in_map (tui_commands[i].key, tui_rl_command_key, tui_keymap);
 346
 347   rl_generic_bind (ISKMAP, "\\C-x", (char*) tui_ctlx_keymap, tui_keymap);
 348
 349   /* Bind all other keys to tui_rl_command_mode so that we switch
 350      temporarily from SingleKey mode and can enter a gdb command.  */
 351   for (i = ' '; i < 0x7f; i++)
 352     {
 353       int j;
 354
 355       for (j = 0; tui_commands[j].cmd; j++)
 356         if (tui_commands[j].key == i)
 357           break;
 358
 359       if (tui_commands[j].cmd)
 360         continue;
 361
 362       rl_bind_key_in_map (i, tui_rl_command_mode, tui_keymap);
 363     }
 364
 365   rl_bind_key_in_map ('a', tui_rl_switch_mode, emacs_ctlx_keymap);
 366   rl_bind_key_in_map ('a', tui_rl_switch_mode, tui_ctlx_keymap);
 367   rl_bind_key_in_map ('A', tui_rl_switch_mode, emacs_ctlx_keymap);
 368   rl_bind_key_in_map ('A', tui_rl_switch_mode, tui_ctlx_keymap);
 369   rl_bind_key_in_map (CTRL ('A'), tui_rl_switch_mode, emacs_ctlx_keymap);
 370   rl_bind_key_in_map (CTRL ('A'), tui_rl_switch_mode, tui_ctlx_keymap);
 371   rl_bind_key_in_map ('1', tui_rl_delete_other_windows, emacs_ctlx_keymap);
 372   rl_bind_key_in_map ('1', tui_rl_delete_other_windows, tui_ctlx_keymap);
 373   rl_bind_key_in_map ('2', tui_rl_change_windows, emacs_ctlx_keymap);
 374   rl_bind_key_in_map ('2', tui_rl_change_windows, tui_ctlx_keymap);
 375   rl_bind_key_in_map ('o', tui_rl_other_window, emacs_ctlx_keymap);
 376   rl_bind_key_in_map ('o', tui_rl_other_window, tui_ctlx_keymap);
 377   rl_bind_key_in_map ('q', tui_rl_next_keymap, tui_keymap);
 378   rl_bind_key_in_map ('s', tui_rl_next_keymap, emacs_ctlx_keymap);
 379   rl_bind_key_in_map ('s', tui_rl_next_keymap, tui_ctlx_keymap);
 380 }
 381
 382 /* Return the TERM variable from the environment, or "<unset>"
 383    if not set.  */
 384
 385 static const char *
 386 gdb_getenv_term (void)
 387 {
 388   const char *term;
 389
 390   term = getenv ("TERM");
 391   if (term != NULL)
 392     return term;
 393   return "<unset>";
 394 }
 395
 396 /* Enter in the tui mode (curses).
 397    When in normal mode, it installs the tui hooks in gdb, redirects
 398    the gdb output, configures the readline to work in tui mode.
 399    When in curses mode, it does nothing.  */
 400 void
 401 tui_enable (void)
 402 {
 403   if (tui_active)
 404     return;
 405
 406   /* To avoid to initialize curses when gdb starts, there is a defered
 407      curses initialization.  This initialization is made only once
 408      and the first time the curses mode is entered.  */
 409   if (tui_finish_init)
 410     {
 411       WINDOW *w;
 412       SCREEN *s;
 413       const char *cap;
 414       const char *interp;
 415
 416       /* If the top level interpreter is not the console/tui (e.g.,
 417          MI), enabling curses will certainly lose.  */
 418       interp = top_level_interpreter ()->name ();
 419       if (strcmp (interp, INTERP_TUI) != 0)
 420         error (_("Cannot enable the TUI when the interpreter is '%s'"), interp);
 421
 422       /* Don't try to setup curses (and print funny control
 423          characters) if we're not outputting to a terminal.  */
 424       if (!ui_file_isatty (gdb_stdout))
 425         error (_("Cannot enable the TUI when output is not a terminal"));
 426
 427       s = newterm (NULL, stdout, stdin);
 428 #ifdef __MINGW32__
 429       /* The MinGW port of ncurses requires $TERM to be unset in order
 430          to activate the Windows console driver.  */
 431       if (s == NULL)
 432         s = newterm ((char *) "unknown", stdout, stdin);
 433 #endif
 434       if (s == NULL)
 435         {
 436           error (_("Cannot enable the TUI: error opening terminal [TERM=%s]"),
 437                  gdb_getenv_term ());
 438         }
 439       w = stdscr;
 440       if (has_colors ())
 441         {
 442 #ifdef HAVE_USE_DEFAULT_COLORS
 443           /* Ncurses extension to help with resetting to the default
 444              color.  */
 445           use_default_colors ();
 446 #endif
 447           start_color ();
 448         }
 449
 450       /* Check required terminal capabilities.  The MinGW port of
 451          ncurses does have them, but doesn't expose them through "cup".  */
 452 #ifndef __MINGW32__
 453       cap = tigetstr ((char *) "cup");
 454       if (cap == NULL || cap == (char *) -1 || *cap == '\0')
 455         {
 456           endwin ();
 457           delscreen (s);
 458           error (_("Cannot enable the TUI: "
 459                    "terminal doesn't support cursor addressing [TERM=%s]"),
 460                  gdb_getenv_term ());
 461         }
 462 #endif
 463
 464       cbreak ();
 465       noecho ();
 466       /* timeout (1); */
 467       nodelay(w, FALSE);
 468       nl();
 469       keypad (w, TRUE);
 470       rl_initialize ();
 471       tui_set_term_height_to (LINES);
 472       tui_set_term_width_to (COLS);
 473       def_prog_mode ();
 474
 475       tui_show_frame_info (0);
 476       tui_set_layout (SRC_COMMAND);
 477       tui_set_win_focus_to (TUI_SRC_WIN);
 478       keypad (TUI_CMD_WIN->generic.handle, TRUE);
 479       wrefresh (TUI_CMD_WIN->generic.handle);
 480       tui_finish_init = 0;
 481     }
 482   else
 483     {
 484      /* Save the current gdb setting of the terminal.
 485         Curses will restore this state when endwin() is called.  */
 486      def_shell_mode ();
 487      clearok (stdscr, TRUE);
 488    }
 489
 490   /* Install the TUI specific hooks.  */
 491   tui_install_hooks ();
 492   rl_startup_hook = tui_rl_startup_hook;
 493
 494   tui_update_variables ();
 495
 496   tui_setup_io (1);
 497
 498   tui_active = 1;
 499
 500   /* Resize windows before anything might display/refresh a
 501      window.  */
 502   if (tui_win_resized ())
 503     {
 504       tui_set_win_resized_to (FALSE);
 505       tui_resize_all ();
 506     }
 507
 508   if (deprecated_safe_get_selected_frame ())
 509     tui_show_frame_info (deprecated_safe_get_selected_frame ());
 510
 511   /* Restore TUI keymap.  */
 512   tui_set_key_mode (tui_current_key_mode);
 513
 514   /* Refresh the screen.  */
 515   tui_refresh_all_win ();
 516
 517   /* Update gdb's knowledge of its terminal.  */
 518   gdb_save_tty_state ();
 519   tui_update_gdb_sizes ();
 520 }
 521
 522 /* Leave the tui mode.
 523    Remove the tui hooks and configure the gdb output and readline
 524    back to their original state.  The curses mode is left so that
 525    the terminal setting is restored to the point when we entered.  */
 526 void
 527 tui_disable (void)
 528 {
 529   if (!tui_active)
 530     return;
 531
 532   /* Restore initial readline keymap.  */
 533   rl_set_keymap (tui_readline_standard_keymap);
 534
 535   /* Remove TUI hooks.  */
 536   tui_remove_hooks ();
 537   rl_startup_hook = 0;
 538   rl_already_prompted = 0;
 539
 540   /* Leave curses and restore previous gdb terminal setting.  */
 541   endwin ();
 542
 543   /* gdb terminal has changed, update gdb internal copy of it
 544      so that terminal management with the inferior works.  */
 545   tui_setup_io (0);
 546
 547   /* Update gdb's knowledge of its terminal.  */
 548   gdb_save_tty_state ();
 549
 550   tui_active = 0;
 551   tui_update_gdb_sizes ();
 552 }
 553
 554 /* Command wrapper for enabling tui mode.  */
 555
 556 static void
 557 tui_enable_command (const char *args, int from_tty)
 558 {
 559   tui_enable ();
 560 }
 561
 562 /* Command wrapper for leaving tui mode.  */
 563
 564 static void
 565 tui_disable_command (const char *args, int from_tty)
 566 {
 567   tui_disable ();
 568 }
 569
 570 void
 571 strcat_to_buf (char *buf, int buflen,
 572                const char *item_to_add)
 573 {
 574   if (item_to_add != NULL && buf != NULL)
 575     {
 576       if ((strlen (buf) + strlen (item_to_add)) <= buflen)
 577         strcat (buf, item_to_add);
 578       else
 579         strncat (buf, item_to_add, (buflen - strlen (buf)));
 580     }
 581 }
 582
 583 #if 0
 584 /* Solaris <sys/termios.h> defines CTRL.  */
 585 #ifndef CTRL
 586 #define CTRL(x)         (x & ~0140)
 587 #endif
 588
 589 #define FILEDES         2
 590 #define CHK(val, dft)   (val<=0 ? dft : val)
 591
 592 static void
 593 tui_reset (void)
 594 {
 595   struct termio mode;
 596
 597   /* Reset the teletype mode bits to a sensible state.
 598      Copied tset.c.  */
 599 #if defined (TIOCGETC)
 600   struct tchars tbuf;
 601 #endif /* TIOCGETC */
 602 #ifdef UCB_NTTY
 603   struct ltchars ltc;
 604
 605   if (ldisc == NTTYDISC)
 606     {
 607       ioctl (FILEDES, TIOCGLTC, &ltc);
 608       ltc.t_suspc = CHK (ltc.t_suspc, CTRL ('Z'));
 609       ltc.t_dsuspc = CHK (ltc.t_dsuspc, CTRL ('Y'));
 610       ltc.t_rprntc = CHK (ltc.t_rprntc, CTRL ('R'));
 611       ltc.t_flushc = CHK (ltc.t_flushc, CTRL ('O'));
 612       ltc.t_werasc = CHK (ltc.t_werasc, CTRL ('W'));
 613       ltc.t_lnextc = CHK (ltc.t_lnextc, CTRL ('V'));
 614       ioctl (FILEDES, TIOCSLTC, &ltc);
 615     }
 616 #endif /* UCB_NTTY */
 617 #ifdef TIOCGETC
 618   ioctl (FILEDES, TIOCGETC, &tbuf);
 619   tbuf.t_intrc = CHK (tbuf.t_intrc, CTRL ('?'));
 620   tbuf.t_quitc = CHK (tbuf.t_quitc, CTRL ('\\'));
 621   tbuf.t_startc = CHK (tbuf.t_startc, CTRL ('Q'));
 622   tbuf.t_stopc = CHK (tbuf.t_stopc, CTRL ('S'));
 623   tbuf.t_eofc = CHK (tbuf.t_eofc, CTRL ('D'));
 624   /* brkc is left alone.  */
 625   ioctl (FILEDES, TIOCSETC, &tbuf);
 626 #endif /* TIOCGETC */
 627   mode.sg_flags &= ~(RAW
 628 #ifdef CBREAK
 629                      | CBREAK
 630 #endif /* CBREAK */
 631                      | VTDELAY | ALLDELAY);
 632   mode.sg_flags |= XTABS | ECHO | CRMOD | ANYP;
 633
 634   return;
 635 }
 636 #endif
 637
 638 void
 639 tui_show_source (const char *fullname, int line)
 640 {
 641   struct symtab_and_line cursal = get_current_source_symtab_and_line ();
 642
 643   /* Make sure that the source window is displayed.  */
 644   tui_add_win_to_layout (SRC_WIN);
 645
 646   tui_update_source_windows_with_line (cursal.symtab, line);
 647   tui_update_locator_fullname (fullname);
 648 }
 649
 650 void
 651 tui_show_assembly (struct gdbarch *gdbarch, CORE_ADDR addr)
 652 {
 653   tui_add_win_to_layout (DISASSEM_WIN);
 654   tui_update_source_windows_with_addr (gdbarch, addr);
 655 }
 656
 657 int
 658 tui_is_window_visible (enum tui_win_type type)
 659 {
 660   if (tui_active == 0)
 661     return 0;
 662
 663   if (tui_win_list[type] == 0)
 664     return 0;
 665
 666   return tui_win_list[type]->generic.is_visible;
 667 }
 668
 669 int
 670 tui_get_command_dimension (unsigned int *width,
 671                            unsigned int *height)
 672 {
 673   if (!tui_active || (TUI_CMD_WIN == NULL))
 674     {
 675       return 0;
 676     }
 677
 678   *width = TUI_CMD_WIN->generic.width;
 679   *height = TUI_CMD_WIN->generic.height;
 680   return 1;
 681 }
 682
 683 void
 684 _initialize_tui (void)
 685 {
 686   struct cmd_list_element **tuicmd;
 687
 688   tuicmd = tui_get_cmd_list ();
 689
 690   add_cmd ("enable", class_tui, tui_enable_command,
 691            _("Enable TUI display mode."),
 692            tuicmd);
 693   add_cmd ("disable", class_tui, tui_disable_command,
 694            _("Disable TUI display mode."),
 695            tuicmd);
 696 }