display.c

UNIX下SH的实现源码

  if (META_CHAR (uc))
    return ((_rl_output_meta_chars == 0) ? 4 : 1);

  if (uc == '\t')
    {
#if defined (DISPLAY_TABS)
      return (((pos | 7) + 1) - pos);
#else
      return (2);
#endif /* !DISPLAY_TABS */
    }

  if (CTRL_CHAR (c) || c == RUBOUT)
    return (2);

  return ((isprint (uc)) ? 1 : 2);
}

/* How to print things in the "echo-area".  The prompt is treated as a
   mini-modeline. */

#if defined (USE_VARARGS)
int
#if defined (PREFER_STDARG)
rl_message (const char *format, ...)
#else
rl_message (va_alist)
     va_dcl
#endif
{
  va_list args;
#if defined (PREFER_VARARGS)
  char *format;
#endif

#if defined (PREFER_STDARG)
  va_start (args, format);
#else
  va_start (args);
  format = va_arg (args, char *);
#endif

  vsprintf (msg_buf, format, args);
  va_end (args);

  rl_display_prompt = msg_buf;
  (*rl_redisplay_function) ();
  return 0;
}
#else /* !USE_VARARGS */
int
rl_message (format, arg1, arg2)
     char *format;
{
  sprintf (msg_buf, format, arg1, arg2);
  rl_display_prompt = msg_buf;
  (*rl_redisplay_function) ();
  return 0;
}
#endif /* !USE_VARARGS */

/* How to clear things from the "echo-area". */
int
rl_clear_message ()
{
  rl_display_prompt = rl_prompt;
  (*rl_redisplay_function) ();
  return 0;
}

int
rl_reset_line_state ()
{
  rl_on_new_line ();

  rl_display_prompt = rl_prompt ? rl_prompt : "";
  forced_display = 1;
  return 0;
}

static char *saved_local_prompt;
static char *saved_local_prefix;
static int saved_last_invisible;
static int saved_visible_length;

void
rl_save_prompt ()
{
  saved_local_prompt = local_prompt;
  saved_local_prefix = local_prompt_prefix;
  saved_last_invisible = last_invisible;
  saved_visible_length = visible_length;

  local_prompt = local_prompt_prefix = (char *)0;
  last_invisible = visible_length = 0;
}

void
rl_restore_prompt ()
{
  if (local_prompt)
    free (local_prompt);
  if (local_prompt_prefix)
    free (local_prompt_prefix);

  local_prompt = saved_local_prompt;
  local_prompt_prefix = saved_local_prefix;
  last_invisible = saved_last_invisible;
  visible_length = saved_visible_length;
}

char *
_rl_make_prompt_for_search (pchar)
     int pchar;
{
  int len;
  char *pmt;

  rl_save_prompt ();

  if (saved_local_prompt == 0)
    {
      len = (rl_prompt && *rl_prompt) ? strlen (rl_prompt) : 0;
      pmt = xmalloc (len + 2);
      if (len)
	strcpy (pmt, rl_prompt);
      pmt[len] = pchar;
      pmt[len+1] = '\0';
    }
  else
    {
      len = *saved_local_prompt ? strlen (saved_local_prompt) : 0;
      pmt = xmalloc (len + 2);
      if (len)
	strcpy (pmt, saved_local_prompt);
      pmt[len] = pchar;
      pmt[len+1] = '\0';
      local_prompt = savestring (pmt);
      last_invisible = saved_last_invisible;
      visible_length = saved_visible_length + 1;
    }
  return pmt;
}

/* Quick redisplay hack when erasing characters at the end of the line. */
void
_rl_erase_at_end_of_line (l)
     int l;
{
  register int i;

  _rl_backspace (l);
  for (i = 0; i < l; i++)
    putc (' ', rl_outstream);
  _rl_backspace (l);
  for (i = 0; i < l; i++)
    visible_line[--_rl_last_c_pos] = '\0';
  rl_display_fixed++;
}

/* Clear to the end of the line.  COUNT is the minimum
   number of character spaces to clear, */
void
_rl_clear_to_eol (count)
     int count;
{
  if (term_clreol)
    tputs (term_clreol, 1, _rl_output_character_function);
  else if (count)
    space_to_eol (count);
}

/* Clear to the end of the line using spaces.  COUNT is the minimum
   number of character spaces to clear, */
static void
space_to_eol (count)
     int count;
{
  register int i;

  for (i = 0; i < count; i++)
   putc (' ', rl_outstream);

  _rl_last_c_pos += count;
}

void
_rl_clear_screen ()
{
#ifdef __MSDOS__
  ScreenClear ();	/* FIXME: only works in text modes */
  ScreenSetCursor (0, 0);  /* term_clrpag is "cl" which homes the cursor */
#else
  if (term_clrpag)
    tputs (term_clrpag, 1, _rl_output_character_function);
  else
    crlf ();
#endif
}

/* Insert COUNT characters from STRING to the output stream. */
static void
insert_some_chars (string, count)
     char *string;
     int count;
{
  /* If IC is defined, then we do not have to "enter" insert mode. */
  if (term_IC)
    {
      char *buffer;
      buffer = tgoto (term_IC, 0, count);
      tputs (buffer, 1, _rl_output_character_function);
      _rl_output_some_chars (string, count);
    }
  else
    {
      register int i;

      /* If we have to turn on insert-mode, then do so. */
      if (term_im && *term_im)
	tputs (term_im, 1, _rl_output_character_function);

      /* If there is a special command for inserting characters, then
	 use that first to open up the space. */
      if (term_ic && *term_ic)
	{
	  for (i = count; i--; )
	    tputs (term_ic, 1, _rl_output_character_function);
	}

      /* Print the text. */
      _rl_output_some_chars (string, count);

      /* If there is a string to turn off insert mode, we had best use
	 it now. */
      if (term_ei && *term_ei)
	tputs (term_ei, 1, _rl_output_character_function);
    }
}

/* Delete COUNT characters from the display line. */
static void
delete_chars (count)
     int count;
{
  if (count > screenwidth)	/* XXX */
    return;

  if (term_DC && *term_DC)
    {
      char *buffer;
      buffer = tgoto (term_DC, count, count);
      tputs (buffer, count, _rl_output_character_function);
    }
  else
    {
      if (term_dc && *term_dc)
	while (count--)
	  tputs (term_dc, 1, _rl_output_character_function);
    }
}

void
_rl_update_final ()
{
  int full_lines;

  full_lines = 0;
  /* If the cursor is the only thing on an otherwise-blank last line,
     compensate so we don't print an extra CRLF. */
  if (_rl_vis_botlin && _rl_last_c_pos == 0 &&
	visible_line[vis_lbreaks[_rl_vis_botlin]] == 0)
    {
      _rl_vis_botlin--;
      full_lines = 1;
    }
  _rl_move_vert (_rl_vis_botlin);
  /* If we've wrapped lines, remove the final xterm line-wrap flag. */
  if (full_lines && _rl_term_autowrap && (VIS_LLEN(_rl_vis_botlin) == screenwidth))
    {
      char *last_line;
#if 0
      last_line = &visible_line[inv_lbreaks[_rl_vis_botlin]];
#else
      last_line = &visible_line[vis_lbreaks[_rl_vis_botlin]];
#endif
      _rl_move_cursor_relative (screenwidth - 1, last_line);
      _rl_clear_to_eol (0);
      putc (last_line[screenwidth - 1], rl_outstream);
    }
  _rl_vis_botlin = 0;
  crlf ();
  fflush (rl_outstream);
  rl_display_fixed++;
}

/* Move to the start of the current line. */
static void
cr ()
{
  if (term_cr)
    {
#if defined (__MSDOS__)
      putc ('\r', rl_outstream);
#else
      tputs (term_cr, 1, _rl_output_character_function);
#endif
      _rl_last_c_pos = 0;
    }
}

/* Redraw the last line of a multi-line prompt that may possibly contain
   terminal escape sequences.  Called with the cursor at column 0 of the
   line to draw the prompt on. */
static void
redraw_prompt (t)
     char *t;
{
  char *oldp, *oldl, *oldlprefix;
  int oldlen, oldlast, oldplen;

  /* Geez, I should make this a struct. */
  oldp = rl_display_prompt;
  oldl = local_prompt;
  oldlprefix = local_prompt_prefix;
  oldlen = visible_length;
  oldplen = prefix_length;
  oldlast = last_invisible;

  rl_display_prompt = t;
  local_prompt = expand_prompt (t, &visible_length, &last_invisible);
  local_prompt_prefix = (char *)NULL;
  rl_forced_update_display ();

  rl_display_prompt = oldp;
  local_prompt = oldl;
  local_prompt_prefix = oldlprefix;
  visible_length = oldlen;
  prefix_length = oldplen;
  last_invisible = oldlast;
}
      
/* Redisplay the current line after a SIGWINCH is received. */
void
_rl_redisplay_after_sigwinch ()
{
  char *t;

  /* Clear the current line and put the cursor at column 0.  Make sure
     the right thing happens if we have wrapped to a new screen line. */
  if (term_cr)
    {
#if defined (__MSDOS__)
      putc ('\r', rl_outstream);
#else
      tputs (term_cr, 1, _rl_output_character_function);
#endif
      _rl_last_c_pos = 0;
#if defined (__MSDOS__)
      space_to_eol (screenwidth);
      putc ('\r', rl_outstream);
#else
      if (term_clreol)
	tputs (term_clreol, 1, _rl_output_character_function);
      else
	{
	  space_to_eol (screenwidth);
	  tputs (term_cr, 1, _rl_output_character_function);
	}
#endif
      if (_rl_last_v_pos > 0)
	_rl_move_vert (0);
    }
  else
    crlf ();

  /* Redraw only the last line of a multi-line prompt. */
  t = strrchr (rl_display_prompt, '\n');
  if (t)
    redraw_prompt (++t);
  else
    rl_forced_update_display ();
}

void
_rl_clean_up_for_exit ()
{
  if (readline_echoing_p)
    {
      _rl_move_vert (_rl_vis_botlin);
      _rl_vis_botlin = 0;
      fflush (rl_outstream);
      rl_restart_output (1, 0);
    }
}

void
_rl_erase_entire_line ()
{
  cr ();
  _rl_clear_to_eol (0);
  cr ();
  fflush (rl_outstream);
}

/* return the `current display line' of the cursor -- the number of lines to
   move up to get to the first screen line of the current readline line. */
int
_rl_current_display_line ()
{
  int ret, nleft;

  /* Find out whether or not there might be invisible characters in the
     editing buffer. */
  if (rl_display_prompt == rl_prompt)
    nleft = _rl_last_c_pos - screenwidth - rl_visible_prompt_length;
  else
    nleft = _rl_last_c_pos - screenwidth;

  if (nleft > 0)
    ret = 1 + nleft / screenwidth;
  else
    ret = 0;

  return ret;
}