readline/readline/terminal.c - binutils-gdb - Git at Google

 /* terminal.c -- controlling the terminal with termcap. */

 /* Copyright (C) 1996-2017 Free Software Foundation, Inc.

    This file is part of the GNU Readline Library (Readline), a library
    for reading lines of text with interactive input and history editing.

    Readline 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.

    Readline 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 Readline.  If not, see <http://www.gnu.org/licenses/>.
 */

 #define READLINE_LIBRARY

 #if defined (HAVE_CONFIG_H)
 #  include <config.h>
 #endif

 #include <sys/types.h>
 #include "posixstat.h"
 #include <fcntl.h>
 #if defined (HAVE_SYS_FILE_H)
 #  include <sys/file.h>
 #endif /* HAVE_SYS_FILE_H */

 #if defined (HAVE_UNISTD_H)
 #  include <unistd.h>
 #endif /* HAVE_UNISTD_H */

 #if defined (HAVE_STDLIB_H)
 #  include <stdlib.h>
 #else
 #  include "ansi_stdlib.h"
 #endif /* HAVE_STDLIB_H */

 #if defined (HAVE_LOCALE_H)
 #  include <locale.h>
 #endif

 #include <stdio.h>

 /* System-specific feature definitions and include files. */
 #include "rldefs.h"

 #ifdef __MSDOS__
 #  include <pc.h>
 #endif

 #include "rltty.h"
 #if defined (HAVE_SYS_IOCTL_H)
 #  include <sys/ioctl.h>		/* include for declaration of ioctl */
 #endif
 #include "tcap.h"

 /* Some standard library routines. */
 #include "readline.h"
 #include "history.h"

 #include "rlprivate.h"
 #include "rlshell.h"
 #include "xmalloc.h"

 #if defined (__MINGW32__)
 #  include <windows.h>
 #  include <wincon.h>

 static void _win_get_screensize PARAMS((int *, int *));
 #endif

 #if defined (__EMX__)
 static void _emx_get_screensize PARAMS((int *, int *));
 #endif

 /* If the calling application sets this to a non-zero value, readline will
    use the $LINES and $COLUMNS environment variables to set its idea of the
    window size before interrogating the kernel. */
 int rl_prefer_env_winsize = 0;

 /* If this is non-zero, readline will set LINES and COLUMNS in the
    environment when it handles SIGWINCH. */
 int rl_change_environment = 1;

 /* **************************************************************** */
 /*								    */
 /*			Terminal and Termcap			    */
 /*								    */
 /* **************************************************************** */

 #ifndef __MSDOS__
 static char *term_buffer = (char *)NULL;
 static char *term_string_buffer = (char *)NULL;
 #endif

 static int tcap_initialized;

 #if !defined (__linux__) && !defined (NCURSES_VERSION)
 #  if defined (__EMX__) || defined (NEED_EXTERN_PC)
 extern
 #  endif /* __EMX__ || NEED_EXTERN_PC */
 char PC, *BC, *UP;
 #endif /* !__linux__ && !NCURSES_VERSION */

 /* Some strings to control terminal actions.  These are output by tputs (). */
 char *_rl_term_clreol;
 char *_rl_term_clrpag;
 char *_rl_term_clrscroll;
 char *_rl_term_cr;
 char *_rl_term_backspace;
 char *_rl_term_goto;
 char *_rl_term_pc;

 /* Non-zero if we determine that the terminal can do character insertion. */
 int _rl_terminal_can_insert = 0;

 /* How to insert characters. */
 char *_rl_term_im;
 char *_rl_term_ei;
 char *_rl_term_ic;
 char *_rl_term_ip;
 char *_rl_term_IC;

 /* How to delete characters. */
 char *_rl_term_dc;
 char *_rl_term_DC;

 /* How to move forward a char, non-destructively */
 char *_rl_term_forward_char;

 /* How to go up a line. */
 char *_rl_term_up;

 /* A visible bell; char if the terminal can be made to flash the screen. */
 static char *_rl_visible_bell;

 /* Non-zero means the terminal can auto-wrap lines. */
 int _rl_term_autowrap = -1;

 /* Non-zero means that this terminal has a meta key. */
 static int term_has_meta;

 /* The sequences to write to turn on and off the meta key, if this
    terminal has one. */
 static char *_rl_term_mm;
 static char *_rl_term_mo;

 /* The sequences to enter and exit standout mode. */
 static char *_rl_term_so;
 static char *_rl_term_se;

 /* The key sequences output by the arrow keys, if this terminal has any. */
 static char *_rl_term_ku;
 static char *_rl_term_kd;
 static char *_rl_term_kr;
 static char *_rl_term_kl;

 /* How to initialize and reset the arrow keys, if this terminal has any. */
 static char *_rl_term_ks;
 static char *_rl_term_ke;

 /* The key sequences sent by the Home and End keys, if any. */
 static char *_rl_term_kh;
 static char *_rl_term_kH;
 static char *_rl_term_at7;	/* @7 */

 /* Delete key */
 static char *_rl_term_kD;

 /* Insert key */
 static char *_rl_term_kI;

 /* Cursor control */
 static char *_rl_term_vs;	/* very visible */
 static char *_rl_term_ve;	/* normal */

 /* It's not clear how HPUX is so broken here. */
 #ifdef TGETENT_BROKEN
 #  define TGETENT_SUCCESS 0
 #else
 #  define TGETENT_SUCCESS 1
 #endif
 #ifdef TGETFLAG_BROKEN
 #  define TGETFLAG_SUCCESS 0
 #else
 #  define TGETFLAG_SUCCESS 1
 #endif
 #define TGETFLAG(cap)	(tgetflag (cap) == TGETFLAG_SUCCESS)

 static void bind_termcap_arrow_keys PARAMS((Keymap));

 /* Variables that hold the screen dimensions, used by the display code. */
 int _rl_screenwidth, _rl_screenheight, _rl_screenchars;

 /* Non-zero means the user wants to enable the keypad. */
 int _rl_enable_keypad;

 /* Non-zero means the user wants to enable a meta key. */
 int _rl_enable_meta = 1;

 #if defined (__EMX__)
 static void
 _emx_get_screensize (int *swp, int *shp)
 {
   int sz[2];

   _scrsize (sz);

   if (swp)
     *swp = sz[0];
   if (shp)
     *shp = sz[1];
 }
 #endif

 #if defined (__MINGW32__)
 static void
 _win_get_screensize (int *swp, int *shp)
 {
   HANDLE hConOut;
   CONSOLE_SCREEN_BUFFER_INFO scr;

   hConOut = GetStdHandle (STD_OUTPUT_HANDLE);
   if (hConOut != INVALID_HANDLE_VALUE)
     {
       if (GetConsoleScreenBufferInfo (hConOut, &scr))
 	{
 	  *swp = scr.dwSize.X;
 	  *shp = scr.srWindow.Bottom - scr.srWindow.Top + 1;
 	}
     }
 }
 #endif

 /* Get readline's idea of the screen size.  TTY is a file descriptor open
    to the terminal.  If IGNORE_ENV is true, we do not pay attention to the
    values of $LINES and $COLUMNS.  The tests for TERM_STRING_BUFFER being
    non-null serve to check whether or not we have initialized termcap. */
 void
 _rl_get_screen_size (int tty, int ignore_env)
 {
   char *ss;
 #if defined (TIOCGWINSZ)
   struct winsize window_size;
 #endif /* TIOCGWINSZ */
   int wr, wc;

   wr = wc = -1;
 #if defined (TIOCGWINSZ)
   if (ioctl (tty, TIOCGWINSZ, &window_size) == 0)
     {
       wc = (int) window_size.ws_col;
       wr = (int) window_size.ws_row;
     }
 #endif /* TIOCGWINSZ */

 #if defined (__EMX__)
   _emx_get_screensize (&wc, &wr);
 #elif defined (__MINGW32__)
   _win_get_screensize (&wc, &wr);
 #endif

   if (ignore_env || rl_prefer_env_winsize == 0)
     {
       _rl_screenwidth = wc;
       _rl_screenheight = wr;
     }
   else
     _rl_screenwidth = _rl_screenheight = -1;

   /* Environment variable COLUMNS overrides setting of "co" if IGNORE_ENV
      is unset.  If we prefer the environment, check it first before
      assigning the value returned by the kernel. */
   if (_rl_screenwidth <= 0)
     {
       if (ignore_env == 0 && (ss = sh_get_env_value ("COLUMNS")))
 	_rl_screenwidth = atoi (ss);

       if (_rl_screenwidth <= 0)
         _rl_screenwidth = wc;

 #if defined (__DJGPP__)
       if (_rl_screenwidth <= 0)
 	_rl_screenwidth = ScreenCols ();
 #else
       if (_rl_screenwidth <= 0 && term_string_buffer)
 	_rl_screenwidth = tgetnum ("co");
 #endif
     }

   /* Environment variable LINES overrides setting of "li" if IGNORE_ENV
      is unset. */
   if (_rl_screenheight <= 0)
     {
       if (ignore_env == 0 && (ss = sh_get_env_value ("LINES")))
 	_rl_screenheight = atoi (ss);

       if (_rl_screenheight <= 0)
         _rl_screenheight = wr;

 #if defined (__DJGPP__)
       if (_rl_screenheight <= 0)
 	_rl_screenheight = ScreenRows ();
 #else
       if (_rl_screenheight <= 0 && term_string_buffer)
 	_rl_screenheight = tgetnum ("li");
 #endif
     }

   /* If all else fails, default to 80x24 terminal. */
   if (_rl_screenwidth <= 1)
     _rl_screenwidth = 80;

   if (_rl_screenheight <= 0)
     _rl_screenheight = 24;

   /* If we're being compiled as part of bash, set the environment
      variables $LINES and $COLUMNS to new values.  Otherwise, just
      do a pair of putenv () or setenv () calls. */
   if (rl_change_environment)
     sh_set_lines_and_columns (_rl_screenheight, _rl_screenwidth);

   if (_rl_term_autowrap == 0)
     _rl_screenwidth--;

   _rl_screenchars = _rl_screenwidth * _rl_screenheight;
 }

 void
 _rl_set_screen_size (int rows, int cols)
 {
   if (_rl_term_autowrap == -1)
     _rl_init_terminal_io (rl_terminal_name);

   if (rows > 0)
     _rl_screenheight = rows;
   if (cols > 0)
     {
       _rl_screenwidth = cols;
       if (_rl_term_autowrap == 0)
 	_rl_screenwidth--;
     }

   if (rows > 0 || cols > 0)
     _rl_screenchars = _rl_screenwidth * _rl_screenheight;
 }

 void
 rl_set_screen_size (int rows, int cols)
 {
   _rl_set_screen_size (rows, cols);
 }

 void
 rl_get_screen_size (int *rows, int *cols)
 {
   if (rows)
     *rows = _rl_screenheight;
   if (cols)
     *cols = _rl_screenwidth;
 }

 void
 rl_reset_screen_size (void)
 {
   _rl_get_screen_size (fileno (rl_instream), 0);
 }

 void
 _rl_sigwinch_resize_terminal (void)
 {
   _rl_get_screen_size (fileno (rl_instream), 1);
 }

 void
 rl_resize_terminal (void)
 {
   _rl_get_screen_size (fileno (rl_instream), 1);
   if (_rl_echoing_p)
     {
       if (CUSTOM_REDISPLAY_FUNC ())
 	rl_forced_update_display ();
       else if (RL_ISSTATE(RL_STATE_REDISPLAYING) == 0)
 	_rl_redisplay_after_sigwinch ();
     }
 }

 struct _tc_string {
      const char * const tc_var;
      char **tc_value;
 };

 /* This should be kept sorted, just in case we decide to change the
    search algorithm to something smarter. */
 static const struct _tc_string tc_strings[] =
 {
   { "@7", &_rl_term_at7 },
   { "DC", &_rl_term_DC },
   { "E3", &_rl_term_clrscroll },
   { "IC", &_rl_term_IC },
   { "ce", &_rl_term_clreol },
   { "cl", &_rl_term_clrpag },
   { "cr", &_rl_term_cr },
   { "dc", &_rl_term_dc },
   { "ei", &_rl_term_ei },
   { "ic", &_rl_term_ic },
   { "im", &_rl_term_im },
   { "kD", &_rl_term_kD },	/* delete */
   { "kH", &_rl_term_kH },	/* home down ?? */
   { "kI", &_rl_term_kI },	/* insert */
   { "kd", &_rl_term_kd },
   { "ke", &_rl_term_ke },	/* end keypad mode */
   { "kh", &_rl_term_kh },	/* home */
   { "kl", &_rl_term_kl },
   { "kr", &_rl_term_kr },
   { "ks", &_rl_term_ks },	/* start keypad mode */
   { "ku", &_rl_term_ku },
   { "le", &_rl_term_backspace },
   { "mm", &_rl_term_mm },
   { "mo", &_rl_term_mo },
   { "nd", &_rl_term_forward_char },
   { "pc", &_rl_term_pc },
   { "se", &_rl_term_se },
   { "so", &_rl_term_so },
   { "up", &_rl_term_up },
   { "vb", &_rl_visible_bell },
   { "vs", &_rl_term_vs },
   { "ve", &_rl_term_ve },
 };

 #define NUM_TC_STRINGS (sizeof (tc_strings) / sizeof (struct _tc_string))

 /* Read the desired terminal capability strings into BP.  The capabilities
    are described in the TC_STRINGS table. */
 static void
 get_term_capabilities (char **bp)
 {
 #if !defined (__DJGPP__)	/* XXX - doesn't DJGPP have a termcap library? */
   register int i;

   for (i = 0; i < NUM_TC_STRINGS; i++)
     *(tc_strings[i].tc_value) = tgetstr ((char *)tc_strings[i].tc_var, bp);
 #endif
   tcap_initialized = 1;
 }

 int
 _rl_init_terminal_io (const char *terminal_name)
 {
   const char *term;
   char *buffer;
   int tty, tgetent_ret, dumbterm;

   term = terminal_name ? terminal_name : sh_get_env_value ("TERM");
   _rl_term_clrpag = _rl_term_cr = _rl_term_clreol = _rl_term_clrscroll = (char *)NULL;
   tty = rl_instream ? fileno (rl_instream) : 0;

   if (term == 0)
     term = "dumb";

   dumbterm = STREQ (term, "dumb");

 #ifdef __MSDOS__
   _rl_term_im = _rl_term_ei = _rl_term_ic = _rl_term_IC = (char *)NULL;
   _rl_term_up = _rl_term_dc = _rl_term_DC = _rl_visible_bell = (char *)NULL;
   _rl_term_ku = _rl_term_kd = _rl_term_kl = _rl_term_kr = (char *)NULL;
   _rl_term_mm = _rl_term_mo = (char *)NULL;
   _rl_terminal_can_insert = term_has_meta = _rl_term_autowrap = 0;
   _rl_term_cr = "\r";
   _rl_term_backspace = (char *)NULL;
   _rl_term_goto = _rl_term_pc = _rl_term_ip = (char *)NULL;
   _rl_term_ks = _rl_term_ke =_rl_term_vs = _rl_term_ve = (char *)NULL;
   _rl_term_kh = _rl_term_kH = _rl_term_at7 = _rl_term_kI = (char *)NULL;
   _rl_term_so = _rl_term_se = (char *)NULL;
 #if defined(HACK_TERMCAP_MOTION)
   _rl_term_forward_char = (char *)NULL;
 #endif

   _rl_get_screen_size (tty, 0);
 #else  /* !__MSDOS__ */
   /* I've separated this out for later work on not calling tgetent at all
      if the calling application has supplied a custom redisplay function,
      (and possibly if the application has supplied a custom input function). */
   if (CUSTOM_REDISPLAY_FUNC())
     {
       tgetent_ret = -1;
     }
   else
     {
       if (term_string_buffer == 0)
 	term_string_buffer = (char *)xmalloc(2032);

       if (term_buffer == 0)
 	term_buffer = (char *)xmalloc(4080);

       buffer = term_string_buffer;

       tgetent_ret = tgetent (term_buffer, term);
     }

   if (tgetent_ret != TGETENT_SUCCESS)
     {
       FREE (term_string_buffer);
       FREE (term_buffer);
       buffer = term_buffer = term_string_buffer = (char *)NULL;

       _rl_term_autowrap = 0;	/* used by _rl_get_screen_size */

       /* Allow calling application to set default height and width, using
 	 rl_set_screen_size */
       if (_rl_screenwidth <= 0 || _rl_screenheight <= 0)
 	{
 #if defined (__EMX__)
 	  _emx_get_screensize (&_rl_screenwidth, &_rl_screenheight);
 	  _rl_screenwidth--;
 #else /* !__EMX__ */
 	  _rl_get_screen_size (tty, 0);
 #endif /* !__EMX__ */
 	}

       /* Defaults. */
       if (_rl_screenwidth <= 0 || _rl_screenheight <= 0)
         {
 	  _rl_screenwidth = 79;
 	  _rl_screenheight = 24;
         }

       /* Everything below here is used by the redisplay code (tputs). */
       _rl_screenchars = _rl_screenwidth * _rl_screenheight;
       _rl_term_cr = "\r";
       _rl_term_im = _rl_term_ei = _rl_term_ic = _rl_term_IC = (char *)NULL;
       _rl_term_up = _rl_term_dc = _rl_term_DC = _rl_visible_bell = (char *)NULL;
       _rl_term_ku = _rl_term_kd = _rl_term_kl = _rl_term_kr = (char *)NULL;
       _rl_term_kh = _rl_term_kH = _rl_term_kI = _rl_term_kD = (char *)NULL;
       _rl_term_ks = _rl_term_ke = _rl_term_at7 = (char *)NULL;
       _rl_term_mm = _rl_term_mo = (char *)NULL;
       _rl_term_ve = _rl_term_vs = (char *)NULL;
       _rl_term_forward_char = (char *)NULL;
       _rl_term_so = _rl_term_se = (char *)NULL;
       _rl_terminal_can_insert = term_has_meta = 0;

       /* Assume generic unknown terminal can't handle the enable/disable
 	 escape sequences */
       _rl_enable_bracketed_paste = 0;

       /* Reasonable defaults for tgoto().  Readline currently only uses
          tgoto if _rl_term_IC or _rl_term_DC is defined, but just in case we
          change that later... */
       PC = '\0';
       BC = _rl_term_backspace = "\b";
       UP = _rl_term_up;

       return 0;
     }

   get_term_capabilities (&buffer);

   /* Set up the variables that the termcap library expects the application
      to provide. */
   PC = _rl_term_pc ? *_rl_term_pc : 0;
   BC = _rl_term_backspace;
   UP = _rl_term_up;

   if (_rl_term_cr == 0)
     _rl_term_cr = "\r";

   _rl_term_autowrap = TGETFLAG ("am") && TGETFLAG ("xn");

   /* Allow calling application to set default height and width, using
      rl_set_screen_size */
   if (_rl_screenwidth <= 0 || _rl_screenheight <= 0)
     _rl_get_screen_size (tty, 0);

   /* "An application program can assume that the terminal can do
       character insertion if *any one of* the capabilities `IC',
       `im', `ic' or `ip' is provided."  But we can't do anything if
       only `ip' is provided, so... */
   _rl_terminal_can_insert = (_rl_term_IC || _rl_term_im || _rl_term_ic);

   /* Check to see if this terminal has a meta key and clear the capability
      variables if there is none. */
   term_has_meta = TGETFLAG ("km");
   if (term_has_meta == 0)
     _rl_term_mm = _rl_term_mo = (char *)NULL;
 #endif /* !__MSDOS__ */

   /* Attempt to find and bind the arrow keys.  Do not override already
      bound keys in an overzealous attempt, however. */

   bind_termcap_arrow_keys (emacs_standard_keymap);

 #if defined (VI_MODE)
   bind_termcap_arrow_keys (vi_movement_keymap);
   bind_termcap_arrow_keys (vi_insertion_keymap);
 #endif /* VI_MODE */

   /* There's no way to determine whether or not a given terminal supports
      bracketed paste mode, so we assume a terminal named "dumb" does not. */
   if (dumbterm)
     _rl_enable_bracketed_paste = 0;

   return 0;
 }

 /* Bind the arrow key sequences from the termcap description in MAP. */
 static void
 bind_termcap_arrow_keys (Keymap map)
 {
   Keymap xkeymap;

   xkeymap = _rl_keymap;
   _rl_keymap = map;

   rl_bind_keyseq_if_unbound (_rl_term_ku, rl_get_previous_history);
   rl_bind_keyseq_if_unbound (_rl_term_kd, rl_get_next_history);
   rl_bind_keyseq_if_unbound (_rl_term_kr, rl_forward_char);
   rl_bind_keyseq_if_unbound (_rl_term_kl, rl_backward_char);

   rl_bind_keyseq_if_unbound (_rl_term_kh, rl_beg_of_line);	/* Home */
   rl_bind_keyseq_if_unbound (_rl_term_at7, rl_end_of_line);	/* End */

   rl_bind_keyseq_if_unbound (_rl_term_kD, rl_delete);
   rl_bind_keyseq_if_unbound (_rl_term_kI, rl_overwrite_mode);	/* Insert */

   _rl_keymap = xkeymap;
 }

 char *
 rl_get_termcap (const char *cap)
 {
   register int i;

   if (tcap_initialized == 0)
     return ((char *)NULL);
   for (i = 0; i < NUM_TC_STRINGS; i++)
     {
       if (tc_strings[i].tc_var[0] == cap[0] && strcmp (tc_strings[i].tc_var, cap) == 0)
         return *(tc_strings[i].tc_value);
     }
   return ((char *)NULL);
 }

 /* Re-initialize the terminal considering that the TERM/TERMCAP variable
    has changed. */
 int
 rl_reset_terminal (const char *terminal_name)
 {
   _rl_screenwidth = _rl_screenheight = 0;
   _rl_init_terminal_io (terminal_name);
   return 0;
 }

 /* A function for the use of tputs () */
 #ifdef _MINIX
 void
 _rl_output_character_function (int c)
 {
   putc (c, _rl_out_stream);
 }
 #else /* !_MINIX */
 int
 _rl_output_character_function (int c)
 {
   return putc (c, _rl_out_stream);
 }
 #endif /* !_MINIX */

 /* Write COUNT characters from STRING to the output stream. */
 void
 _rl_output_some_chars (const char *string, int count)
 {
   fwrite (string, 1, count, _rl_out_stream);
 }

 /* Move the cursor back. */
 int
 _rl_backspace (int count)
 {
   register int i;

 #ifndef __MSDOS__
   if (_rl_term_backspace)
     for (i = 0; i < count; i++)
       tputs (_rl_term_backspace, 1, _rl_output_character_function);
   else
 #endif
     for (i = 0; i < count; i++)
       putc ('\b', _rl_out_stream);
   return 0;
 }

 /* Move to the start of the next line. */
 int
 rl_crlf (void)
 {
 #if defined (NEW_TTY_DRIVER) || defined (__MINT__)
   if (_rl_term_cr)
     tputs (_rl_term_cr, 1, _rl_output_character_function);
 #endif /* NEW_TTY_DRIVER || __MINT__ */
   putc ('\n', _rl_out_stream);
   return 0;
 }

 void
 _rl_cr (void)
 {
 #if defined (__MSDOS__)
   putc ('\r', rl_outstream);
 #else
   tputs (_rl_term_cr, 1, _rl_output_character_function);
 #endif
 }

 /* Ring the terminal bell. */
 int
 rl_ding (void)
 {
   if (_rl_echoing_p)
     {
       switch (_rl_bell_preference)
         {
 	case NO_BELL:
 	default:
 	  break;
 	case VISIBLE_BELL:
 	  if (_rl_visible_bell)
 	    {
 #ifdef __DJGPP__
 	      ScreenVisualBell ();
 #else
 	      tputs (_rl_visible_bell, 1, _rl_output_character_function);
 #endif
 	      break;
 	    }
 	  /* FALLTHROUGH */
 	case AUDIBLE_BELL:
 	  fprintf (stderr, "\007");
 	  fflush (stderr);
 	  break;
         }
       return (0);
     }
   return (-1);
 }

 /* **************************************************************** */
 /*								    */
 /*		Entering and leaving terminal standout mode	    */
 /*								    */
 /* **************************************************************** */

 void
 _rl_standout_on (void)
 {
 #ifndef __MSDOS__
   if (_rl_term_so && _rl_term_se)
     tputs (_rl_term_so, 1, _rl_output_character_function);
 #endif
 }

 void
 _rl_standout_off (void)
 {
 #ifndef __MSDOS__
   if (_rl_term_so && _rl_term_se)
     tputs (_rl_term_se, 1, _rl_output_character_function);
 #endif
 }

 /* **************************************************************** */
 /*								    */
 /*	 	Controlling the Meta Key and Keypad		    */
 /*								    */
 /* **************************************************************** */

 static int enabled_meta = 0;	/* flag indicating we enabled meta mode */

 void
 _rl_enable_meta_key (void)
 {
 #if !defined (__DJGPP__)
   if (term_has_meta && _rl_term_mm)
     {
       tputs (_rl_term_mm, 1, _rl_output_character_function);
       enabled_meta = 1;
     }
 #endif
 }

 void
 _rl_disable_meta_key (void)
 {
 #if !defined (__DJGPP__)
   if (term_has_meta && _rl_term_mo && enabled_meta)
     {
       tputs (_rl_term_mo, 1, _rl_output_character_function);
       enabled_meta = 0;
     }
 #endif
 }

 void
 _rl_control_keypad (int on)
 {
 #if !defined (__DJGPP__)
   if (on && _rl_term_ks)
     tputs (_rl_term_ks, 1, _rl_output_character_function);
   else if (!on && _rl_term_ke)
     tputs (_rl_term_ke, 1, _rl_output_character_function);
 #endif
 }

 /* **************************************************************** */
 /*								    */
 /*	 		Controlling the Cursor			    */
 /*								    */
 /* **************************************************************** */

 /* Set the cursor appropriately depending on IM, which is one of the
    insert modes (insert or overwrite).  Insert mode gets the normal
    cursor.  Overwrite mode gets a very visible cursor.  Only does
    anything if we have both capabilities. */
 void
 _rl_set_cursor (int im, int force)
 {
 #ifndef __MSDOS__
   if (_rl_term_ve && _rl_term_vs)
     {
       if (force || im != rl_insert_mode)
 	{
 	  if (im == RL_IM_OVERWRITE)
 	    tputs (_rl_term_vs, 1, _rl_output_character_function);
 	  else
 	    tputs (_rl_term_ve, 1, _rl_output_character_function);
 	}
     }
 #endif
 }
	/* terminal.c -- controlling the terminal with termcap. */

	/* Copyright (C) 1996-2017 Free Software Foundation, Inc.

	This file is part of the GNU Readline Library (Readline), a library
	for reading lines of text with interactive input and history editing.

	Readline 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.

	Readline 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 Readline. If not, see <http://www.gnu.org/licenses/>.
	*/

	#define READLINE_LIBRARY

	#if defined (HAVE_CONFIG_H)
	# include <config.h>
	#endif

	#include <sys/types.h>
	#include "posixstat.h"
	#include <fcntl.h>
	#if defined (HAVE_SYS_FILE_H)
	# include <sys/file.h>
	#endif /* HAVE_SYS_FILE_H */

	#if defined (HAVE_UNISTD_H)
	# include <unistd.h>
	#endif /* HAVE_UNISTD_H */

	#if defined (HAVE_STDLIB_H)
	# include <stdlib.h>
	#else
	# include "ansi_stdlib.h"
	#endif /* HAVE_STDLIB_H */

	#if defined (HAVE_LOCALE_H)
	# include <locale.h>
	#endif

	#include <stdio.h>

	/* System-specific feature definitions and include files. */
	#include "rldefs.h"

	#ifdef __MSDOS__
	# include <pc.h>
	#endif

	#include "rltty.h"
	#if defined (HAVE_SYS_IOCTL_H)
	# include <sys/ioctl.h> /* include for declaration of ioctl */
	#endif
	#include "tcap.h"

	/* Some standard library routines. */
	#include "readline.h"
	#include "history.h"

	#include "rlprivate.h"
	#include "rlshell.h"
	#include "xmalloc.h"

	#if defined (__MINGW32__)
	# include <windows.h>
	# include <wincon.h>

	static void _win_get_screensize PARAMS((int , int ));
	#endif

	#if defined (__EMX__)
	static void _emx_get_screensize PARAMS((int , int ));
	#endif

	/* If the calling application sets this to a non-zero value, readline will
	use the $LINES and $COLUMNS environment variables to set its idea of the
	window size before interrogating the kernel. */
	int rl_prefer_env_winsize = 0;

	/* If this is non-zero, readline will set LINES and COLUMNS in the
	environment when it handles SIGWINCH. */
	int rl_change_environment = 1;

	/* **************************************************************** */
	/* */
	/* Terminal and Termcap */
	/* */
	/* **************************************************************** */

	#ifndef __MSDOS__
	static char term_buffer = (char )NULL;
	static char term_string_buffer = (char )NULL;
	#endif

	static int tcap_initialized;

	#if !defined (__linux__) && !defined (NCURSES_VERSION)
	# if defined (__EMX__) \|\| defined (NEED_EXTERN_PC)
	extern
	# endif /* __EMX__ \|\| NEED_EXTERN_PC */
	char PC, BC, UP;
	#endif /* !__linux__ && !NCURSES_VERSION */

	/* Some strings to control terminal actions. These are output by tputs (). */
	char *_rl_term_clreol;
	char *_rl_term_clrpag;
	char *_rl_term_clrscroll;
	char *_rl_term_cr;
	char *_rl_term_backspace;
	char *_rl_term_goto;
	char *_rl_term_pc;

	/* Non-zero if we determine that the terminal can do character insertion. */
	int _rl_terminal_can_insert = 0;

	/* How to insert characters. */
	char *_rl_term_im;
	char *_rl_term_ei;
	char *_rl_term_ic;
	char *_rl_term_ip;
	char *_rl_term_IC;

	/* How to delete characters. */
	char *_rl_term_dc;
	char *_rl_term_DC;

	/* How to move forward a char, non-destructively */
	char *_rl_term_forward_char;

	/* How to go up a line. */
	char *_rl_term_up;

	/* A visible bell; char if the terminal can be made to flash the screen. */
	static char *_rl_visible_bell;

	/* Non-zero means the terminal can auto-wrap lines. */
	int _rl_term_autowrap = -1;

	/* Non-zero means that this terminal has a meta key. */
	static int term_has_meta;

	/* The sequences to write to turn on and off the meta key, if this
	terminal has one. */
	static char *_rl_term_mm;
	static char *_rl_term_mo;

	/* The sequences to enter and exit standout mode. */
	static char *_rl_term_so;
	static char *_rl_term_se;

	/* The key sequences output by the arrow keys, if this terminal has any. */
	static char *_rl_term_ku;
	static char *_rl_term_kd;
	static char *_rl_term_kr;
	static char *_rl_term_kl;

	/* How to initialize and reset the arrow keys, if this terminal has any. */
	static char *_rl_term_ks;
	static char *_rl_term_ke;

	/* The key sequences sent by the Home and End keys, if any. */
	static char *_rl_term_kh;
	static char *_rl_term_kH;
	static char _rl_term_at7; / @7 */

	/* Delete key */
	static char *_rl_term_kD;

	/* Insert key */
	static char *_rl_term_kI;

	/* Cursor control */
	static char _rl_term_vs; / very visible */
	static char _rl_term_ve; / normal */

	/* It's not clear how HPUX is so broken here. */
	#ifdef TGETENT_BROKEN
	# define TGETENT_SUCCESS 0
	#else
	# define TGETENT_SUCCESS 1
	#endif
	#ifdef TGETFLAG_BROKEN
	# define TGETFLAG_SUCCESS 0
	#else
	# define TGETFLAG_SUCCESS 1
	#endif
	#define TGETFLAG(cap) (tgetflag (cap) == TGETFLAG_SUCCESS)

	static void bind_termcap_arrow_keys PARAMS((Keymap));

	/* Variables that hold the screen dimensions, used by the display code. */
	int _rl_screenwidth, _rl_screenheight, _rl_screenchars;

	/* Non-zero means the user wants to enable the keypad. */
	int _rl_enable_keypad;

	/* Non-zero means the user wants to enable a meta key. */
	int _rl_enable_meta = 1;

	#if defined (__EMX__)
	static void
	_emx_get_screensize (int swp, int shp)
	{
	int sz[2];

	_scrsize (sz);

	if (swp)
	*swp = sz[0];
	if (shp)
	*shp = sz[1];
	}
	#endif

	#if defined (__MINGW32__)
	static void
	_win_get_screensize (int swp, int shp)
	{
	HANDLE hConOut;
	CONSOLE_SCREEN_BUFFER_INFO scr;

	hConOut = GetStdHandle (STD_OUTPUT_HANDLE);
	if (hConOut != INVALID_HANDLE_VALUE)
	{
	if (GetConsoleScreenBufferInfo (hConOut, &scr))
	{
	*swp = scr.dwSize.X;
	*shp = scr.srWindow.Bottom - scr.srWindow.Top + 1;
	}
	}
	}
	#endif

	/* Get readline's idea of the screen size. TTY is a file descriptor open
	to the terminal. If IGNORE_ENV is true, we do not pay attention to the
	values of $LINES and $COLUMNS. The tests for TERM_STRING_BUFFER being
	non-null serve to check whether or not we have initialized termcap. */
	void
	_rl_get_screen_size (int tty, int ignore_env)
	{
	char *ss;
	#if defined (TIOCGWINSZ)
	struct winsize window_size;
	#endif /* TIOCGWINSZ */
	int wr, wc;

	wr = wc = -1;
	#if defined (TIOCGWINSZ)
	if (ioctl (tty, TIOCGWINSZ, &window_size) == 0)
	{
	wc = (int) window_size.ws_col;
	wr = (int) window_size.ws_row;
	}
	#endif /* TIOCGWINSZ */

	#if defined (__EMX__)
	_emx_get_screensize (&wc, &wr);
	#elif defined (__MINGW32__)
	_win_get_screensize (&wc, &wr);
	#endif

	if (ignore_env \|\| rl_prefer_env_winsize == 0)
	{
	_rl_screenwidth = wc;
	_rl_screenheight = wr;
	}
	else
	_rl_screenwidth = _rl_screenheight = -1;

	/* Environment variable COLUMNS overrides setting of "co" if IGNORE_ENV
	is unset. If we prefer the environment, check it first before
	assigning the value returned by the kernel. */
	if (_rl_screenwidth <= 0)
	{
	if (ignore_env == 0 && (ss = sh_get_env_value ("COLUMNS")))
	_rl_screenwidth = atoi (ss);

	if (_rl_screenwidth <= 0)
	_rl_screenwidth = wc;

	#if defined (__DJGPP__)
	if (_rl_screenwidth <= 0)
	_rl_screenwidth = ScreenCols ();
	#else
	if (_rl_screenwidth <= 0 && term_string_buffer)
	_rl_screenwidth = tgetnum ("co");
	#endif
	}

	/* Environment variable LINES overrides setting of "li" if IGNORE_ENV
	is unset. */
	if (_rl_screenheight <= 0)
	{
	if (ignore_env == 0 && (ss = sh_get_env_value ("LINES")))
	_rl_screenheight = atoi (ss);

	if (_rl_screenheight <= 0)
	_rl_screenheight = wr;

	#if defined (__DJGPP__)
	if (_rl_screenheight <= 0)
	_rl_screenheight = ScreenRows ();
	#else
	if (_rl_screenheight <= 0 && term_string_buffer)
	_rl_screenheight = tgetnum ("li");
	#endif
	}

	/* If all else fails, default to 80x24 terminal. */
	if (_rl_screenwidth <= 1)
	_rl_screenwidth = 80;

	if (_rl_screenheight <= 0)
	_rl_screenheight = 24;

	/* If we're being compiled as part of bash, set the environment
	variables $LINES and $COLUMNS to new values. Otherwise, just
	do a pair of putenv () or setenv () calls. */
	if (rl_change_environment)
	sh_set_lines_and_columns (_rl_screenheight, _rl_screenwidth);

	if (_rl_term_autowrap == 0)
	_rl_screenwidth--;

	_rl_screenchars = _rl_screenwidth * _rl_screenheight;
	}

	void
	_rl_set_screen_size (int rows, int cols)
	{
	if (_rl_term_autowrap == -1)
	_rl_init_terminal_io (rl_terminal_name);

	if (rows > 0)
	_rl_screenheight = rows;
	if (cols > 0)
	{
	_rl_screenwidth = cols;
	if (_rl_term_autowrap == 0)
	_rl_screenwidth--;
	}

	if (rows > 0 \|\| cols > 0)
	_rl_screenchars = _rl_screenwidth * _rl_screenheight;
	}

	void
	rl_set_screen_size (int rows, int cols)
	{
	_rl_set_screen_size (rows, cols);
	}

	void
	rl_get_screen_size (int rows, int cols)
	{
	if (rows)
	*rows = _rl_screenheight;
	if (cols)
	*cols = _rl_screenwidth;
	}

	void
	rl_reset_screen_size (void)
	{
	_rl_get_screen_size (fileno (rl_instream), 0);
	}

	void
	_rl_sigwinch_resize_terminal (void)
	{
	_rl_get_screen_size (fileno (rl_instream), 1);
	}

	void
	rl_resize_terminal (void)
	{
	_rl_get_screen_size (fileno (rl_instream), 1);
	if (_rl_echoing_p)
	{
	if (CUSTOM_REDISPLAY_FUNC ())
	rl_forced_update_display ();
	else if (RL_ISSTATE(RL_STATE_REDISPLAYING) == 0)
	_rl_redisplay_after_sigwinch ();
	}
	}

	struct _tc_string {
	const char * const tc_var;
	char **tc_value;
	};

	/* This should be kept sorted, just in case we decide to change the
	search algorithm to something smarter. */
	static const struct _tc_string tc_strings[] =
	{
	{ "@7", &_rl_term_at7 },
	{ "DC", &_rl_term_DC },
	{ "E3", &_rl_term_clrscroll },
	{ "IC", &_rl_term_IC },
	{ "ce", &_rl_term_clreol },
	{ "cl", &_rl_term_clrpag },
	{ "cr", &_rl_term_cr },
	{ "dc", &_rl_term_dc },
	{ "ei", &_rl_term_ei },
	{ "ic", &_rl_term_ic },
	{ "im", &_rl_term_im },
	{ "kD", &_rl_term_kD }, /* delete */
	{ "kH", &_rl_term_kH }, /* home down ?? */
	{ "kI", &_rl_term_kI }, /* insert */
	{ "kd", &_rl_term_kd },
	{ "ke", &_rl_term_ke }, /* end keypad mode */
	{ "kh", &_rl_term_kh }, /* home */
	{ "kl", &_rl_term_kl },
	{ "kr", &_rl_term_kr },
	{ "ks", &_rl_term_ks }, /* start keypad mode */
	{ "ku", &_rl_term_ku },
	{ "le", &_rl_term_backspace },
	{ "mm", &_rl_term_mm },
	{ "mo", &_rl_term_mo },
	{ "nd", &_rl_term_forward_char },
	{ "pc", &_rl_term_pc },
	{ "se", &_rl_term_se },
	{ "so", &_rl_term_so },
	{ "up", &_rl_term_up },
	{ "vb", &_rl_visible_bell },
	{ "vs", &_rl_term_vs },
	{ "ve", &_rl_term_ve },
	};

	#define NUM_TC_STRINGS (sizeof (tc_strings) / sizeof (struct _tc_string))

	/* Read the desired terminal capability strings into BP. The capabilities
	are described in the TC_STRINGS table. */
	static void
	get_term_capabilities (char **bp)
	{
	#if !defined (__DJGPP__) /* XXX - doesn't DJGPP have a termcap library? */
	register int i;

	for (i = 0; i < NUM_TC_STRINGS; i++)
	(tc_strings[i].tc_value) = tgetstr ((char )tc_strings[i].tc_var, bp);
	#endif
	tcap_initialized = 1;
	}

	int
	_rl_init_terminal_io (const char *terminal_name)
	{
	const char *term;
	char *buffer;
	int tty, tgetent_ret, dumbterm;

	term = terminal_name ? terminal_name : sh_get_env_value ("TERM");
	_rl_term_clrpag = _rl_term_cr = _rl_term_clreol = _rl_term_clrscroll = (char *)NULL;
	tty = rl_instream ? fileno (rl_instream) : 0;

	if (term == 0)
	term = "dumb";

	dumbterm = STREQ (term, "dumb");

	#ifdef __MSDOS__
	_rl_term_im = _rl_term_ei = _rl_term_ic = _rl_term_IC = (char *)NULL;
	_rl_term_up = _rl_term_dc = _rl_term_DC = _rl_visible_bell = (char *)NULL;
	_rl_term_ku = _rl_term_kd = _rl_term_kl = _rl_term_kr = (char *)NULL;
	_rl_term_mm = _rl_term_mo = (char *)NULL;
	_rl_terminal_can_insert = term_has_meta = _rl_term_autowrap = 0;
	_rl_term_cr = "\r";
	_rl_term_backspace = (char *)NULL;
	_rl_term_goto = _rl_term_pc = _rl_term_ip = (char *)NULL;
	_rl_term_ks = _rl_term_ke =_rl_term_vs = _rl_term_ve = (char *)NULL;
	_rl_term_kh = _rl_term_kH = _rl_term_at7 = _rl_term_kI = (char *)NULL;
	_rl_term_so = _rl_term_se = (char *)NULL;
	#if defined(HACK_TERMCAP_MOTION)
	_rl_term_forward_char = (char *)NULL;
	#endif

	_rl_get_screen_size (tty, 0);
	#else /* !__MSDOS__ */
	/* I've separated this out for later work on not calling tgetent at all
	if the calling application has supplied a custom redisplay function,
	(and possibly if the application has supplied a custom input function). */
	if (CUSTOM_REDISPLAY_FUNC())
	{
	tgetent_ret = -1;
	}
	else
	{
	if (term_string_buffer == 0)
	term_string_buffer = (char *)xmalloc(2032);

	if (term_buffer == 0)
	term_buffer = (char *)xmalloc(4080);

	buffer = term_string_buffer;

	tgetent_ret = tgetent (term_buffer, term);
	}

	if (tgetent_ret != TGETENT_SUCCESS)
	{
	FREE (term_string_buffer);
	FREE (term_buffer);
	buffer = term_buffer = term_string_buffer = (char *)NULL;

	_rl_term_autowrap = 0; /* used by _rl_get_screen_size */

	/* Allow calling application to set default height and width, using
	rl_set_screen_size */
	if (_rl_screenwidth <= 0 \|\| _rl_screenheight <= 0)
	{
	#if defined (__EMX__)
	_emx_get_screensize (&_rl_screenwidth, &_rl_screenheight);
	_rl_screenwidth--;
	#else /* !__EMX__ */
	_rl_get_screen_size (tty, 0);
	#endif /* !__EMX__ */
	}

	/* Defaults. */
	if (_rl_screenwidth <= 0 \|\| _rl_screenheight <= 0)
	{
	_rl_screenwidth = 79;
	_rl_screenheight = 24;
	}

	/* Everything below here is used by the redisplay code (tputs). */
	_rl_screenchars = _rl_screenwidth * _rl_screenheight;
	_rl_term_cr = "\r";
	_rl_term_im = _rl_term_ei = _rl_term_ic = _rl_term_IC = (char *)NULL;
	_rl_term_up = _rl_term_dc = _rl_term_DC = _rl_visible_bell = (char *)NULL;
	_rl_term_ku = _rl_term_kd = _rl_term_kl = _rl_term_kr = (char *)NULL;
	_rl_term_kh = _rl_term_kH = _rl_term_kI = _rl_term_kD = (char *)NULL;
	_rl_term_ks = _rl_term_ke = _rl_term_at7 = (char *)NULL;
	_rl_term_mm = _rl_term_mo = (char *)NULL;
	_rl_term_ve = _rl_term_vs = (char *)NULL;
	_rl_term_forward_char = (char *)NULL;
	_rl_term_so = _rl_term_se = (char *)NULL;
	_rl_terminal_can_insert = term_has_meta = 0;

	/* Assume generic unknown terminal can't handle the enable/disable
	escape sequences */
	_rl_enable_bracketed_paste = 0;

	/* Reasonable defaults for tgoto(). Readline currently only uses
	tgoto if _rl_term_IC or _rl_term_DC is defined, but just in case we
	change that later... */
	PC = '\0';
	BC = _rl_term_backspace = "\b";
	UP = _rl_term_up;

	return 0;
	}

	get_term_capabilities (&buffer);

	/* Set up the variables that the termcap library expects the application
	to provide. */
	PC = _rl_term_pc ? *_rl_term_pc : 0;
	BC = _rl_term_backspace;
	UP = _rl_term_up;

	if (_rl_term_cr == 0)
	_rl_term_cr = "\r";

	_rl_term_autowrap = TGETFLAG ("am") && TGETFLAG ("xn");

	/* Allow calling application to set default height and width, using
	rl_set_screen_size */
	if (_rl_screenwidth <= 0 \|\| _rl_screenheight <= 0)
	_rl_get_screen_size (tty, 0);

	/* "An application program can assume that the terminal can do
	character insertion if any one of the capabilities `IC',
	`im', `ic' or `ip' is provided." But we can't do anything if
	only `ip' is provided, so... */
	_rl_terminal_can_insert = (_rl_term_IC \|\| _rl_term_im \|\| _rl_term_ic);

	/* Check to see if this terminal has a meta key and clear the capability
	variables if there is none. */
	term_has_meta = TGETFLAG ("km");
	if (term_has_meta == 0)
	_rl_term_mm = _rl_term_mo = (char *)NULL;
	#endif /* !__MSDOS__ */

	/* Attempt to find and bind the arrow keys. Do not override already
	bound keys in an overzealous attempt, however. */

	bind_termcap_arrow_keys (emacs_standard_keymap);

	#if defined (VI_MODE)
	bind_termcap_arrow_keys (vi_movement_keymap);
	bind_termcap_arrow_keys (vi_insertion_keymap);
	#endif /* VI_MODE */

	/* There's no way to determine whether or not a given terminal supports
	bracketed paste mode, so we assume a terminal named "dumb" does not. */
	if (dumbterm)
	_rl_enable_bracketed_paste = 0;

	return 0;
	}

	/* Bind the arrow key sequences from the termcap description in MAP. */
	static void
	bind_termcap_arrow_keys (Keymap map)
	{
	Keymap xkeymap;

	xkeymap = _rl_keymap;
	_rl_keymap = map;

	rl_bind_keyseq_if_unbound (_rl_term_ku, rl_get_previous_history);
	rl_bind_keyseq_if_unbound (_rl_term_kd, rl_get_next_history);
	rl_bind_keyseq_if_unbound (_rl_term_kr, rl_forward_char);
	rl_bind_keyseq_if_unbound (_rl_term_kl, rl_backward_char);

	rl_bind_keyseq_if_unbound (_rl_term_kh, rl_beg_of_line); /* Home */
	rl_bind_keyseq_if_unbound (_rl_term_at7, rl_end_of_line); /* End */

	rl_bind_keyseq_if_unbound (_rl_term_kD, rl_delete);
	rl_bind_keyseq_if_unbound (_rl_term_kI, rl_overwrite_mode); /* Insert */

	_rl_keymap = xkeymap;
	}

	char *
	rl_get_termcap (const char *cap)
	{
	register int i;

	if (tcap_initialized == 0)
	return ((char *)NULL);
	for (i = 0; i < NUM_TC_STRINGS; i++)
	{
	if (tc_strings[i].tc_var[0] == cap[0] && strcmp (tc_strings[i].tc_var, cap) == 0)
	return *(tc_strings[i].tc_value);
	}
	return ((char *)NULL);
	}

	/* Re-initialize the terminal considering that the TERM/TERMCAP variable
	has changed. */
	int
	rl_reset_terminal (const char *terminal_name)
	{
	_rl_screenwidth = _rl_screenheight = 0;
	_rl_init_terminal_io (terminal_name);
	return 0;
	}

	/* A function for the use of tputs () */
	#ifdef _MINIX
	void
	_rl_output_character_function (int c)
	{
	putc (c, _rl_out_stream);
	}
	#else /* !_MINIX */
	int
	_rl_output_character_function (int c)
	{
	return putc (c, _rl_out_stream);
	}
	#endif /* !_MINIX */

	/* Write COUNT characters from STRING to the output stream. */
	void
	_rl_output_some_chars (const char *string, int count)
	{
	fwrite (string, 1, count, _rl_out_stream);
	}

	/* Move the cursor back. */
	int
	_rl_backspace (int count)
	{
	register int i;

	#ifndef __MSDOS__
	if (_rl_term_backspace)
	for (i = 0; i < count; i++)
	tputs (_rl_term_backspace, 1, _rl_output_character_function);
	else
	#endif
	for (i = 0; i < count; i++)
	putc ('\b', _rl_out_stream);
	return 0;
	}

	/* Move to the start of the next line. */
	int
	rl_crlf (void)
	{
	#if defined (NEW_TTY_DRIVER) \|\| defined (__MINT__)
	if (_rl_term_cr)
	tputs (_rl_term_cr, 1, _rl_output_character_function);
	#endif /* NEW_TTY_DRIVER \|\| __MINT__ */
	putc ('\n', _rl_out_stream);
	return 0;
	}

	void
	_rl_cr (void)
	{
	#if defined (__MSDOS__)
	putc ('\r', rl_outstream);
	#else
	tputs (_rl_term_cr, 1, _rl_output_character_function);
	#endif
	}

	/* Ring the terminal bell. */
	int
	rl_ding (void)
	{
	if (_rl_echoing_p)
	{
	switch (_rl_bell_preference)
	{
	case NO_BELL:
	default:
	break;
	case VISIBLE_BELL:
	if (_rl_visible_bell)
	{
	#ifdef __DJGPP__
	ScreenVisualBell ();
	#else
	tputs (_rl_visible_bell, 1, _rl_output_character_function);
	#endif
	break;
	}
	/* FALLTHROUGH */
	case AUDIBLE_BELL:
	fprintf (stderr, "\007");
	fflush (stderr);
	break;
	}
	return (0);
	}
	return (-1);
	}

	/* **************************************************************** */
	/* */
	/* Entering and leaving terminal standout mode */
	/* */
	/* **************************************************************** */

	void
	_rl_standout_on (void)
	{
	#ifndef __MSDOS__
	if (_rl_term_so && _rl_term_se)
	tputs (_rl_term_so, 1, _rl_output_character_function);
	#endif
	}

	void
	_rl_standout_off (void)
	{
	#ifndef __MSDOS__
	if (_rl_term_so && _rl_term_se)
	tputs (_rl_term_se, 1, _rl_output_character_function);
	#endif
	}

	/* **************************************************************** */
	/* */
	/* Controlling the Meta Key and Keypad */
	/* */
	/* **************************************************************** */

	static int enabled_meta = 0; /* flag indicating we enabled meta mode */

	void
	_rl_enable_meta_key (void)
	{
	#if !defined (__DJGPP__)
	if (term_has_meta && _rl_term_mm)
	{
	tputs (_rl_term_mm, 1, _rl_output_character_function);
	enabled_meta = 1;
	}
	#endif
	}

	void
	_rl_disable_meta_key (void)
	{
	#if !defined (__DJGPP__)
	if (term_has_meta && _rl_term_mo && enabled_meta)
	{
	tputs (_rl_term_mo, 1, _rl_output_character_function);
	enabled_meta = 0;
	}
	#endif
	}

	void
	_rl_control_keypad (int on)
	{
	#if !defined (__DJGPP__)
	if (on && _rl_term_ks)
	tputs (_rl_term_ks, 1, _rl_output_character_function);
	else if (!on && _rl_term_ke)
	tputs (_rl_term_ke, 1, _rl_output_character_function);
	#endif
	}

	/* **************************************************************** */
	/* */
	/* Controlling the Cursor */
	/* */
	/* **************************************************************** */

	/* Set the cursor appropriately depending on IM, which is one of the
	insert modes (insert or overwrite). Insert mode gets the normal
	cursor. Overwrite mode gets a very visible cursor. Only does
	anything if we have both capabilities. */
	void
	_rl_set_cursor (int im, int force)
	{
	#ifndef __MSDOS__
	if (_rl_term_ve && _rl_term_vs)
	{
	if (force \|\| im != rl_insert_mode)
	{
	if (im == RL_IM_OVERWRITE)
	tputs (_rl_term_vs, 1, _rl_output_character_function);
	else
	tputs (_rl_term_ve, 1, _rl_output_character_function);
	}
	}
	#endif
	}