readline.c

linux下bash的源码

  rl_pending_input = key;
  return (rl_digit_loop ());
}

/* What to do when you abort reading an argument. */
rl_discard_argument ()
{
  ding ();
  rl_clear_message ();
  rl_init_argument ();
  return 0;
}

/* Create a default argument. */
rl_init_argument ()
{
  rl_numeric_arg = rl_arg_sign = 1;
  rl_explicit_arg = 0;
  return 0;
}

/* C-u, universal argument.  Multiply the current argument by 4.
   Read a key.  If the key has nothing to do with arguments, then
   dispatch on it.  If the key is the abort character then abort. */
rl_universal_argument ()
{
  rl_numeric_arg *= 4;
  return (rl_digit_loop ());
}

/* **************************************************************** */
/*								    */
/*			Terminal and Termcap			    */
/*								    */
/* **************************************************************** */

static char *term_buffer = (char *)NULL;
static char *term_string_buffer = (char *)NULL;

static int tcap_initialized = 0;

/* Non-zero means this terminal can't really do anything. */
int dumb_term = 0;
/* On Solaris2, sys/types.h #includes sys/reg.h, which #defines PC.
   Unfortunately, PC is a global variable used by the termcap library. */
#undef PC

#if !defined (__linux__)
/* If this causes problems, add back the `extern'. */
/*extern*/ char PC, *BC, *UP;
#endif /* __linux__ */

/* Some strings to control terminal actions.  These are output by tputs (). */
char *term_goto, *term_clreol, *term_cr, *term_clrpag, *term_backspace;
char *term_pc;

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

/* How to insert characters. */
char *term_im, *term_ei, *term_ic, *term_ip, *term_IC;

/* How to delete characters. */
char *term_dc, *term_DC;

#if defined (HACK_TERMCAP_MOTION)
char *term_forward_char;
#endif  /* HACK_TERMCAP_MOTION */

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

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

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

/* The string to write to turn on the meta key, if this term has one. */
char *term_mm;

/* The string to write to turn off the meta key, if this term has one. */
char *term_mo;

/* The key sequences output by the arrow keys, if this terminal has any. */
char *term_ku, *term_kd, *term_kr, *term_kl;

/* How to initialize and reset the arrow keys, if this terminal has any. */
char *term_ks, *term_ke;

/* Re-initialize the terminal considering that the TERM/TERMCAP variable
   has changed. */
rl_reset_terminal (terminal_name)
     char *terminal_name;
{
  init_terminal_io (terminal_name);
  return 0;
}

/* Set 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_set_screen_size (tty, ignore_env)
     int tty, ignore_env;
{
#if defined (TIOCGWINSZ)
  struct winsize window_size;
#endif /* TIOCGWINSZ */

#if defined (TIOCGWINSZ)
  if (ioctl (tty, TIOCGWINSZ, &window_size) == 0)
    {
      screenwidth = (int) window_size.ws_col;
      screenheight = (int) window_size.ws_row;
    }
#endif /* TIOCGWINSZ */

  /* Environment variable COLUMNS overrides setting of "co" if IGNORE_ENV
     is unset. */
  if (screenwidth <= 0)
    {
      char *sw;

      if (!ignore_env && (sw = getenv ("COLUMNS")))
	screenwidth = atoi (sw);

      if (screenwidth <= 0 && term_string_buffer)
	screenwidth = tgetnum ("co");
    }

  /* Environment variable LINES overrides setting of "li" if IGNORE_ENV
     is unset. */
  if (screenheight <= 0)
    {
      char *sh;

      if (!ignore_env && (sh = getenv ("LINES")))
	screenheight = atoi (sh);

      if (screenheight <= 0 && term_string_buffer)
	screenheight = tgetnum ("li");
    }

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

  if (screenheight <= 0)
    screenheight = 24;

#if defined (SHELL)
  /* If we're being compiled as part of bash, set the environment
     variables $LINES and $COLUMNS to new values. */
  set_lines_and_columns (screenheight, screenwidth);
#endif

  if (!term_xn)
    screenwidth--;

  screenchars = screenwidth * screenheight;
}

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

/* This should be kept sorted, just in case we decide to change the
   search algorithm to something smarter. */
static struct _tc_string tc_strings[] =
{
  "DC", &term_DC,
  "IC", &term_IC,
  "ce", &term_clreol,
  "cl", &term_clrpag,
  "cr", &term_cr,
  "dc", &term_dc,
  "ei", &term_ei,
  "ic", &term_ic,
  "im", &term_im,
  "kd", &term_kd,
  "kl", &term_kl,
  "kr", &term_kr,
  "ku", &term_ku,
  "ks", &term_ks,
  "ke", &term_ke,
  "le", &term_backspace,
  "mm", &term_mm,
  "mo", &term_mo,
#if defined (HACK_TERMCAP_MOTION)
  "nd", &term_forward_char,
#endif
  "pc", &term_pc,
  "up", &term_up,
  "vb", &visible_bell,
};

#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 (bp)
     char **bp;
{
  register int i;

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

static int
init_terminal_io (terminal_name)
     char *terminal_name;
{
#if defined (__GO32__)
  screenwidth = ScreenCols ();
  screenheight = ScreenRows ();
  screenchars = screenwidth * screenheight;
  term_cr = "\r";
  term_im = term_ei = term_ic = term_IC = (char *)NULL;
  term_up = term_dc = term_DC = visible_bell = (char *)NULL;

  /* Does the __GO32__ have a meta key?  I don't know. */
  term_has_meta = 0;
  term_mm = term_mo = (char *)NULL;

  /* It probably has arrow keys, but I don't know what they are. */
  term_ku = term_kd = term_kr = term_kl = (char *)NULL;

#if defined (HACK_TERMCAP_MOTION)
  term_forward_char = (char *)NULL;
#endif /* HACK_TERMCAP_MOTION */
  terminal_can_insert = term_xn = 0;
  return;
#else /* !__GO32__ */

  char *term, *buffer;
  int tty;
  Keymap xkeymap;

  term = terminal_name ? terminal_name : getenv ("TERM");

  if (!term_string_buffer)
    term_string_buffer = xmalloc (2048);

  if (!term_buffer)
    term_buffer = xmalloc (2048);

  buffer = term_string_buffer;

  term_clrpag = term_cr = term_clreol = (char *)NULL;

  if (!term)
    term = "dumb";

  if (tgetent (term_buffer, term) <= 0)
    {
      dumb_term = 1;
      screenwidth = 79;
      screenheight = 24;
      screenchars = 79 * 24;
      term_cr = "\r";
      term_im = term_ei = term_ic = term_IC = (char *)NULL;
      term_up = term_dc = term_DC = visible_bell = (char *)NULL;
      term_ku = term_kd = term_kl = term_kr = (char *)NULL;
#if defined (HACK_TERMCAP_MOTION)
      term_forward_char = (char *)NULL;
#endif
      terminal_can_insert = 0;
      return 0;
    }

  get_term_capabilities (&buffer);

  /* Set up the variables that the termcap library expects the application
     to provide. */
  PC = term_pc ? *term_pc : 0;
  BC = term_backspace;
  UP = term_up;

  if (!term_cr)
    term_cr =  "\r";

  if (rl_instream)
    tty = fileno (rl_instream);
  else
    tty = 0;

  screenwidth = screenheight = 0;

  term_xn = tgetflag ("am") && tgetflag ("xn");

  _rl_set_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... */
  terminal_can_insert = (term_IC || term_im || 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") || tgetflag ("MT"));
  if (!term_has_meta)
    {
      term_mm = (char *)NULL;
      term_mo = (char *)NULL;
    }

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

  _rl_keymap = emacs_standard_keymap;
  _rl_bind_if_unbound (term_ku, rl_get_previous_history);
  _rl_bind_if_unbound (term_kd, rl_get_next_history);
  _rl_bind_if_unbound (term_kr, rl_forward);
  _rl_bind_if_unbound (term_kl, rl_backward);

#if defined (VI_MODE)
  _rl_keymap = vi_movement_keymap;
  _rl_bind_if_unbound (term_ku, rl_get_previous_history);
  _rl_bind_if_unbound (term_kd, rl_get_next_history);
  _rl_bind_if_unbound (term_kr, rl_forward);
  _rl_bind_if_unbound (term_kl, rl_backward);
#endif /* VI_MODE */

  _rl_keymap = xkeymap;

#endif /* !__GO32__ */
  return 0;
}

char *
rl_get_termcap (cap)
     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);
}

/* A function for the use of tputs () */
int
_rl_output_character_function (c)
     int c;
{
  return putc (c, out_stream);
}

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

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

#if !defined (__GO32__)
  if (term_backspace)
    for (i = 0; i < count; i++)
      tputs (term_backspace, 1, _rl_output_character_function);
  else
#endif /* !__GO32__ */
    for (i = 0; i < count; i++)
      putc ('\b', out_stream);
  return 0;
}

/* Move to the start of the next line. */
crlf ()
{
#if defined (NEW_TTY_DRIVER)
  tputs (term_cr, 1, _rl_output_character_function);
#endif /* NEW_TTY_DRIVER */
  putc ('\n', out_stream);
  return 0;
}

rl_tty_status (count, key)
     int count, key;
{
#if defined (TIOCSTAT)
  ioctl (1, TIOCSTAT, (char *)0);
  rl_refresh_line ();
#else
  ding ();
#endif
  return 0;
}


/* **************************************************************** */
/*								    */
/*			Utility Functions			    */
/*								    */
/* **************************************************************** */

/* Return 0 if C is not a member of the class of characters that belong
   in words, or 1 if it is. */

int allow_pathname_alphabetic_chars = 0;
char *pathname_alphabetic_chars = "/-_=~.#$";

int
alphabetic (c)
     int c;
{
  if (pure_alphabetic (c) || (digit_p (c)))
    return (1);

  if (allow_pathname_alphabetic_chars)
    return (strchr (pathname_alphabetic_chars, c) != NULL);
  else
    return (0);
}

/* Ring the terminal bell. */
int
ding ()
{
  if (readline_echoing_p)
    {
#if !defined (__GO32__)
      switch (_rl_bell_preference)
        {
	case NO_BELL:
	default:
	  break;
	case VISIBLE_BELL:
	  if (visible_bell)
	    {
	      tputs (visible_bell, 1, _rl_output_character_function);
	      break;
	    }
	  /* FALLTHROUGH */
	case AUDIBLE_BELL:
	  fprintf (stderr, "\007");
	  fflush (stderr);
	  break;
        }
#else /* __GO32__ */
      fprintf (stderr, "\007");
      fflush (stderr);
#endif /* __GO32__ */
      return (0);
    }
  return (-1);
}

/* How to abort things. */
rl_abort (count, key)
     int count, key;
{
  ding ();
  rl_clear_message ();
  rl_init_argument ();
  rl_pending_input = 0;

  defining_kbd_macro = 0;
  while (executing_macro)
    pop_executing_macro ();

  rl_last_func = (Function *)NULL;
  longjmp (readline_top_level, 1);
}

/* Return a copy of the string between FROM and TO.
   FROM is inclusive, TO is not. */
char *
rl_copy_text (from, to)
     int from, to;
{
  register int length;
  char *copy;

  /* Fix it if the caller is confused. */
  if (from > to)
    {
      int t = from;
      from = to;
      to = t;
    }

  length = to - from;
  copy = xmalloc (1 + length);
  strncpy (copy, the_line + from, length);
  copy[length] = '\0';
  return (copy);
}

/* Increase the size of RL_LINE_BUFFER until it has enough space to hold
   LEN characters. */
void
rl_extend_line_buffer (len)
     int len;
{
  while (len >= rl_line_buffer_len)
    {
      rl_line_buffer_len += DEFAULT_BUFFER_SIZE;
      rl_line_buffer = xrealloc (rl_line_buffer, rl_line_buffer_len);
    }

  the_line = rl_line_buffer;
}


/* **************************************************************** */
/*								    */
/*			Insert and Delete			    */
/*								    */
/* **************************************************************** */

/* Insert a string of text into the line at point.  This is the only
   way that you should do insertion.  rl_insert () calls this
   function. */
rl_insert_text (string)
     char *string;
{
  register int i, l = strlen (string);

  if (rl_end + l >= rl_line_buffer_len)
    rl_extend_line_buffer (rl_end + l);

  for (i = rl_end; i >= rl_point; i--)
    the_line[i + l] = the_line[i];
  strncpy (the_line + rl_point, string, l);

  /* Remember how to undo this if we aren't undoing something. */
  if (!doing_an_undo)
    {
      /* If possible and desirable, concatenate the undos. */
      if ((l == 1) &&
	  rl_undo_list &&
	  (rl_undo_list->what == UNDO_INSERT) &&
	  (rl_undo_list->end == rl_point) &&
	  (rl_undo_list->end - rl_undo_list->start < 20))
	rl_undo_list->end++;
      else
	rl_add_undo (UNDO_INSERT, rl_point, rl_point + l, (char *)NULL);
    }
  rl_point += l;
  rl_end += l;
  the_line[rl_end] = '\0';
  return l;
}

/* Delete the string between FROM and TO.  FROM is
   inclusive, TO is not. */