Useful add-on libraries

1 files changed, 1740 insertions, 0 deletions

diff --git a/readline-4.2/display.c b/readline-4.2/display.c
new file mode 100644
index 0000000..cb1c500
--- /dev/null
+++ b/readline-4.2/display.c
@@ -0,0 +1,1740 @@
+/* display.c -- readline redisplay facility. */
+
+/* Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc.
+
+   This file is part of the GNU Readline Library, a library for
+   reading lines of text with interactive input and history editing.
+
+   The GNU Readline Library 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 2, or
+   (at your option) any later version.
+
+   The GNU Readline Library 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.
+
+   The GNU General Public License is often shipped with GNU software, and
+   is generally kept in a file called COPYING or LICENSE.  If you do not
+   have a copy of the license, write to the Free Software Foundation,
+   59 Temple Place, Suite 330, Boston, MA 02111 USA. */
+#define READLINE_LIBRARY
+
+#if defined (HAVE_CONFIG_H)
+#  include <config.h>
+#endif
+
+#include <sys/types.h>
+
+#if defined (HAVE_UNISTD_H)
+#  include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+
+#include "posixstat.h"
+
+#if defined (HAVE_STDLIB_H)
+#  include <stdlib.h>
+#else
+#  include "ansi_stdlib.h"
+#endif /* HAVE_STDLIB_H */
+
+#include <stdio.h>
+
+/* System-specific feature definitions and include files. */
+#include "rldefs.h"
+
+/* Termcap library stuff. */
+#include "tcap.h"
+
+/* Some standard library routines. */
+#include "readline.h"
+#include "history.h"
+
+#include "rlprivate.h"
+#include "xmalloc.h"
+
+#if !defined (strchr) && !defined (__STDC__)
+extern char *strchr (), *strrchr ();
+#endif /* !strchr && !__STDC__ */
+
+#if defined (HACK_TERMCAP_MOTION)
+extern char *_rl_term_forward_char;
+#endif
+
+static void update_line __P((char *, char *, int, int, int, int));
+static void space_to_eol __P((int));
+static void delete_chars __P((int));
+static void insert_some_chars __P((char *, int));
+static void cr __P((void));
+
+static int *inv_lbreaks, *vis_lbreaks;
+static int inv_lbsize, vis_lbsize;
+
+/* Heuristic used to decide whether it is faster to move from CUR to NEW
+   by backing up or outputting a carriage return and moving forward. */
+#define CR_FASTER(new, cur) (((new) + 1) < ((cur) - (new)))
+
+/* **************************************************************** */
+/*								    */
+/*			Display stuff				    */
+/*								    */
+/* **************************************************************** */
+
+/* This is the stuff that is hard for me.  I never seem to write good
+   display routines in C.  Let's see how I do this time. */
+
+/* (PWP) Well... Good for a simple line updater, but totally ignores
+   the problems of input lines longer than the screen width.
+
+   update_line and the code that calls it makes a multiple line,
+   automatically wrapping line update.  Careful attention needs
+   to be paid to the vertical position variables. */
+
+/* Keep two buffers; one which reflects the current contents of the
+   screen, and the other to draw what we think the new contents should
+   be.  Then compare the buffers, and make whatever changes to the
+   screen itself that we should.  Finally, make the buffer that we
+   just drew into be the one which reflects the current contents of the
+   screen, and place the cursor where it belongs.
+
+   Commands that want to can fix the display themselves, and then let
+   this function know that the display has been fixed by setting the
+   RL_DISPLAY_FIXED variable.  This is good for efficiency. */
+
+/* Application-specific redisplay function. */
+rl_voidfunc_t *rl_redisplay_function = rl_redisplay;
+
+/* Global variables declared here. */
+/* What YOU turn on when you have handled all redisplay yourself. */
+int rl_display_fixed = 0;
+
+int _rl_suppress_redisplay = 0;
+
+/* The stuff that gets printed out before the actual text of the line.
+   This is usually pointing to rl_prompt. */
+char *rl_display_prompt = (char *)NULL;
+
+/* Pseudo-global variables declared here. */
+/* The visible cursor position.  If you print some text, adjust this. */
+int _rl_last_c_pos = 0;
+int _rl_last_v_pos = 0;
+
+/* Number of lines currently on screen minus 1. */
+int _rl_vis_botlin = 0;
+
+/* Variables used only in this file. */
+/* The last left edge of text that was displayed.  This is used when
+   doing horizontal scrolling.  It shifts in thirds of a screenwidth. */
+static int last_lmargin;
+
+/* The line display buffers.  One is the line currently displayed on
+   the screen.  The other is the line about to be displayed. */
+static char *visible_line = (char *)NULL;
+static char *invisible_line = (char *)NULL;
+
+/* A buffer for `modeline' messages. */
+static char msg_buf[128];
+
+/* Non-zero forces the redisplay even if we thought it was unnecessary. */
+static int forced_display;
+
+/* Default and initial buffer size.  Can grow. */
+static int line_size = 1024;
+
+/* Variables to keep track of the expanded prompt string, which may
+   include invisible characters. */
+
+static char *local_prompt, *local_prompt_prefix;
+static int prompt_visible_length, prompt_prefix_length;
+
+/* The number of invisible characters in the line currently being
+   displayed on the screen. */
+static int visible_wrap_offset;
+
+/* The number of invisible characters in the prompt string.  Static so it
+   can be shared between rl_redisplay and update_line */
+static int wrap_offset;
+
+/* The index of the last invisible character in the prompt string. */
+static int prompt_last_invisible;
+
+/* The length (buffer offset) of the first line of the last (possibly
+   multi-line) buffer displayed on the screen. */
+static int visible_first_line_len;
+
+/* Number of invisible characters on the first physical line of the prompt.
+   Only valid when the number of physical characters in the prompt exceeds
+   (or is equal to) _rl_screenwidth. */
+static int prompt_invis_chars_first_line;
+
+static int prompt_last_screen_line;
+
+/* Expand the prompt string S and return the number of visible
+   characters in *LP, if LP is not null.  This is currently more-or-less
+   a placeholder for expansion.  LIP, if non-null is a place to store the
+   index of the last invisible character in the returned string. NIFLP,
+   if non-zero, is a place to store the number of invisible characters in
+   the first prompt line. */
+
+/* Current implementation:
+	\001 (^A) start non-visible characters
+	\002 (^B) end non-visible characters
+   all characters except \001 and \002 (following a \001) are copied to
+   the returned string; all characters except those between \001 and
+   \002 are assumed to be `visible'. */	
+
+static char *
+expand_prompt (pmt, lp, lip, niflp)
+     char *pmt;
+     int *lp, *lip, *niflp;
+{
+  char *r, *ret, *p;
+  int l, rl, last, ignoring, ninvis, invfl;
+
+  /* Short-circuit if we can. */
+  if (strchr (pmt, RL_PROMPT_START_IGNORE) == 0)
+    {
+      r = savestring (pmt);
+      if (lp)
+	*lp = strlen (r);
+      return r;
+    }
+
+  l = strlen (pmt);
+  r = ret = xmalloc (l + 1);
+
+  invfl = 0;	/* invisible chars in first line of prompt */
+
+  for (rl = ignoring = last = ninvis = 0, p = pmt; p && *p; p++)
+    {
+      /* This code strips the invisible character string markers
+	 RL_PROMPT_START_IGNORE and RL_PROMPT_END_IGNORE */
+      if (*p == RL_PROMPT_START_IGNORE)
+	{
+	  ignoring++;
+	  continue;
+	}
+      else if (ignoring && *p == RL_PROMPT_END_IGNORE)
+	{
+	  ignoring = 0;
+	  last = r - ret - 1;
+	  continue;
+	}
+      else
+	{
+	  *r++ = *p;
+	  if (!ignoring)
+	    rl++;
+	  else
+	    ninvis++;
+	  if (rl == _rl_screenwidth)
+	    invfl = ninvis;
+	}
+    }
+
+  if (rl < _rl_screenwidth)
+    invfl = ninvis;
+
+  *r = '\0';
+  if (lp)
+    *lp = rl;
+  if (lip)
+    *lip = last;
+  if (niflp)
+    *niflp = invfl;
+  return ret;
+}
+
+/* Just strip out RL_PROMPT_START_IGNORE and RL_PROMPT_END_IGNORE from
+   PMT and return the rest of PMT. */
+char *
+_rl_strip_prompt (pmt)
+     char *pmt;
+{
+  char *ret;
+
+  ret = expand_prompt (pmt, (int *)NULL, (int *)NULL, (int *)NULL);
+  return ret;
+}
+
+/*
+ * Expand the prompt string into the various display components, if
+ * necessary.
+ *
+ * local_prompt = expanded last line of string in rl_display_prompt
+ *		  (portion after the final newline)
+ * local_prompt_prefix = portion before last newline of rl_display_prompt,
+ *			 expanded via expand_prompt
+ * prompt_visible_length = number of visible characters in local_prompt
+ * prompt_prefix_length = number of visible characters in local_prompt_prefix
+ *
+ * This function is called once per call to readline().  It may also be
+ * called arbitrarily to expand the primary prompt.
+ *
+ * The return value is the number of visible characters on the last line
+ * of the (possibly multi-line) prompt.
+ */
+int
+rl_expand_prompt (prompt)
+     char *prompt;
+{
+  char *p, *t;
+  int c;
+
+  /* Clear out any saved values. */
+  FREE (local_prompt);
+  FREE (local_prompt_prefix);
+
+  local_prompt = local_prompt_prefix = (char *)0;
+  prompt_last_invisible = prompt_visible_length = 0;
+
+  if (prompt == 0 || *prompt == 0)
+    return (0);
+
+  p = strrchr (prompt, '\n');
+  if (!p)
+    {
+      /* The prompt is only one logical line, though it might wrap. */
+      local_prompt = expand_prompt (prompt, &prompt_visible_length,
+					    &prompt_last_invisible,
+					    &prompt_invis_chars_first_line);
+      local_prompt_prefix = (char *)0;
+      return (prompt_visible_length);
+    }
+  else
+    {
+      /* The prompt spans multiple lines. */
+      t = ++p;
+      local_prompt = expand_prompt (p, &prompt_visible_length,
+				       &prompt_last_invisible,
+				       &prompt_invis_chars_first_line);
+      c = *t; *t = '\0';
+      /* The portion of the prompt string up to and including the
+	 final newline is now null-terminated. */
+      local_prompt_prefix = expand_prompt (prompt, &prompt_prefix_length,
+						   (int *)NULL,
+						   &prompt_invis_chars_first_line);
+      *t = c;
+      return (prompt_prefix_length);
+    }
+}
+
+/* Initialize the VISIBLE_LINE and INVISIBLE_LINE arrays, and their associated
+   arrays of line break markers.  MINSIZE is the minimum size of VISIBLE_LINE
+   and INVISIBLE_LINE; if it is greater than LINE_SIZE, LINE_SIZE is
+   increased.  If the lines have already been allocated, this ensures that
+   they can hold at least MINSIZE characters. */
+static void
+init_line_structures (minsize)
+      int minsize;
+{
+  register int n;
+
+  if (invisible_line == 0)	/* initialize it */
+    {
+      if (line_size < minsize)
+	line_size = minsize;
+      visible_line = xmalloc (line_size);
+      invisible_line = xmalloc (line_size);
+    }
+  else if (line_size < minsize)	/* ensure it can hold MINSIZE chars */
+    {
+      line_size *= 2;
+      if (line_size < minsize)
+	line_size = minsize;
+      visible_line = xrealloc (visible_line, line_size);
+      invisible_line = xrealloc (invisible_line, line_size);
+    }
+
+  for (n = minsize; n < line_size; n++)
+    {
+      visible_line[n] = 0;
+      invisible_line[n] = 1;
+    }
+
+  if (vis_lbreaks == 0)
+    {
+      /* should be enough. */
+      inv_lbsize = vis_lbsize = 256;
+      inv_lbreaks = (int *)xmalloc (inv_lbsize * sizeof (int));
+      vis_lbreaks = (int *)xmalloc (vis_lbsize * sizeof (int));
+      inv_lbreaks[0] = vis_lbreaks[0] = 0;
+    }
+}
+  
+/* Basic redisplay algorithm. */
+void
+rl_redisplay ()
+{
+  register int in, out, c, linenum, cursor_linenum;
+  register char *line;
+  int c_pos, inv_botlin, lb_botlin, lb_linenum;
+  int newlines, lpos, temp;
+  char *prompt_this_line;
+
+  if (!readline_echoing_p)
+    return;
+
+  if (!rl_display_prompt)
+    rl_display_prompt = "";
+
+  if (invisible_line == 0)
+    {
+      init_line_structures (0);
+      rl_on_new_line ();
+    }
+
+  /* Draw the line into the buffer. */
+  c_pos = -1;
+
+  line = invisible_line;
+  out = inv_botlin = 0;
+
+  /* Mark the line as modified or not.  We only do this for history
+     lines. */
+  if (_rl_mark_modified_lines && current_history () && rl_undo_list)
+    {
+      line[out++] = '*';
+      line[out] = '\0';
+    }
+
+  /* If someone thought that the redisplay was handled, but the currently
+     visible line has a different modification state than the one about
+     to become visible, then correct the caller's misconception. */
+  if (visible_line[0] != invisible_line[0])
+    rl_display_fixed = 0;
+
+  /* If the prompt to be displayed is the `primary' readline prompt (the
+     one passed to readline()), use the values we have already expanded.
+     If not, use what's already in rl_display_prompt.  WRAP_OFFSET is the
+     number of non-visible characters in the prompt string. */
+  if (rl_display_prompt == rl_prompt || local_prompt)
+    {
+      int local_len = local_prompt ? strlen (local_prompt) : 0;
+      if (local_prompt_prefix && forced_display)
+	_rl_output_some_chars (local_prompt_prefix, strlen (local_prompt_prefix));
+
+      if (local_len > 0)
+	{
+	  temp = local_len + out + 2;
+	  if (temp >= line_size)
+	    {
+	      line_size = (temp + 1024) - (temp % 1024);
+	      visible_line = xrealloc (visible_line, line_size);
+	      line = invisible_line = xrealloc (invisible_line, line_size);
+	    }
+	  strncpy (line + out, local_prompt, local_len);
+	  out += local_len;
+	}
+      line[out] = '\0';
+      wrap_offset = local_len - prompt_visible_length;
+    }
+  else
+    {
+      int pmtlen;
+      prompt_this_line = strrchr (rl_display_prompt, '\n');
+      if (!prompt_this_line)
+	prompt_this_line = rl_display_prompt;
+      else
+	{
+	  prompt_this_line++;
+	  pmtlen = prompt_this_line - rl_display_prompt;	/* temp var */
+	  if (forced_display)
+	    {
+	      _rl_output_some_chars (rl_display_prompt, pmtlen);
+	      /* Make sure we are at column zero even after a newline,
+		 regardless of the state of terminal output processing. */
+	      if (pmtlen < 2 || prompt_this_line[-2] != '\r')
+		cr ();
+	    }
+	}
+
+      pmtlen = strlen (prompt_this_line);
+      temp = pmtlen + out + 2;
+      if (temp >= line_size)
+	{
+	  line_size = (temp + 1024) - (temp % 1024);
+	  visible_line = xrealloc (visible_line, line_size);
+	  line = invisible_line = xrealloc (invisible_line, line_size);
+	}
+      strncpy (line + out,  prompt_this_line, pmtlen);
+      out += pmtlen;
+      line[out] = '\0';
+      wrap_offset = prompt_invis_chars_first_line = 0;
+    }
+
+#define CHECK_INV_LBREAKS() \
+      do { \
+	if (newlines >= (inv_lbsize - 2)) \
+	  { \
+	    inv_lbsize *= 2; \
+	    inv_lbreaks = (int *)xrealloc (inv_lbreaks, inv_lbsize * sizeof (int)); \
+	  } \
+      } while (0)
+	  
+#define CHECK_LPOS() \
+      do { \
+	lpos++; \
+	if (lpos >= _rl_screenwidth) \
+	  { \
+	    if (newlines >= (inv_lbsize - 2)) \
+	      { \
+		inv_lbsize *= 2; \
+		inv_lbreaks = (int *)xrealloc (inv_lbreaks, inv_lbsize * sizeof (int)); \
+	      } \
+	    inv_lbreaks[++newlines] = out; \
+	    lpos = 0; \
+	  } \
+      } while (0)
+
+  /* inv_lbreaks[i] is where line i starts in the buffer. */
+  inv_lbreaks[newlines = 0] = 0;
+  lpos = out - wrap_offset;
+
+  /* prompt_invis_chars_first_line is the number of invisible characters in
+     the first physical line of the prompt.
+     wrap_offset - prompt_invis_chars_first_line is the number of invis
+     chars on the second line. */
+
+  /* what if lpos is already >= _rl_screenwidth before we start drawing the
+     contents of the command line? */
+  while (lpos >= _rl_screenwidth)
+    {
+      /* fix from Darin Johnson <darin@acuson.com> for prompt string with
+         invisible characters that is longer than the screen width.  The
+         prompt_invis_chars_first_line variable could be made into an array
+         saying how many invisible characters there are per line, but that's
+         probably too much work for the benefit gained.  How many people have
+         prompts that exceed two physical lines? */
+      temp = ((newlines + 1) * _rl_screenwidth) +
+             ((newlines == 0) ? prompt_invis_chars_first_line : 0) +
+             ((newlines == 1) ? wrap_offset : 0);
+
+      inv_lbreaks[++newlines] = temp;
+      lpos -= _rl_screenwidth;
+    }
+
+  prompt_last_screen_line = newlines;
+
+  /* Draw the rest of the line (after the prompt) into invisible_line, keeping
+     track of where the cursor is (c_pos), the number of the line containing
+     the cursor (lb_linenum), the last line number (lb_botlin and inv_botlin).
+     It maintains an array of line breaks for display (inv_lbreaks).
+     This handles expanding tabs for display and displaying meta characters. */
+  lb_linenum = 0;
+  for (in = 0; in < rl_end; in++)
+    {
+      c = (unsigned char)rl_line_buffer[in];
+
+      if (out + 8 >= line_size)		/* XXX - 8 for \t */
+	{
+	  line_size *= 2;
+	  visible_line = xrealloc (visible_line, line_size);
+	  invisible_line = xrealloc (invisible_line, line_size);
+	  line = invisible_line;
+	}
+
+      if (in == rl_point)
+	{
+	  c_pos = out;
+	  lb_linenum = newlines;
+	}
+
+      if (META_CHAR (c))
+	{
+	  if (_rl_output_meta_chars == 0)
+	    {
+	      sprintf (line + out, "\\%o", c);
+
+	      if (lpos + 4 >= _rl_screenwidth)
+		{
+		  temp = _rl_screenwidth - lpos;
+		  CHECK_INV_LBREAKS ();
+		  inv_lbreaks[++newlines] = out + temp;
+		  lpos = 4 - temp;
+		}
+	      else
+		lpos += 4;
+
+	      out += 4;
+	    }
+	  else
+	    {
+	      line[out++] = c;
+	      CHECK_LPOS();
+	    }
+	}
+#if defined (DISPLAY_TABS)
+      else if (c == '\t')
+	{
+	  register int newout;
+
+#if 0
+	  newout = (out | (int)7) + 1;
+#else
+	  newout = out + 8 - lpos % 8;
+#endif
+	  temp = newout - out;
+	  if (lpos + temp >= _rl_screenwidth)
+	    {
+	      register int temp2;
+	      temp2 = _rl_screenwidth - lpos;
+	      CHECK_INV_LBREAKS ();
+	      inv_lbreaks[++newlines] = out + temp2;
+	      lpos = temp - temp2;
+	      while (out < newout)
+		line[out++] = ' ';
+	    }
+	  else
+	    {
+	      while (out < newout)
+		line[out++] = ' ';
+	      lpos += temp;
+	    }
+	}
+#endif
+      else if (c == '\n' && _rl_horizontal_scroll_mode == 0 && _rl_term_up && *_rl_term_up)
+	{
+	  line[out++] = '\0';	/* XXX - sentinel */
+	  CHECK_INV_LBREAKS ();
+	  inv_lbreaks[++newlines] = out;
+	  lpos = 0;
+	}
+      else if (CTRL_CHAR (c) || c == RUBOUT)
+	{
+	  line[out++] = '^';
+	  CHECK_LPOS();
+	  line[out++] = CTRL_CHAR (c) ? UNCTRL (c) : '?';
+	  CHECK_LPOS();
+	}
+      else
+	{
+	  line[out++] = c;
+	  CHECK_LPOS();
+	}
+    }
+  line[out] = '\0';
+  if (c_pos < 0)
+    {
+      c_pos = out;
+      lb_linenum = newlines;
+    }
+
+  inv_botlin = lb_botlin = newlines;
+  CHECK_INV_LBREAKS ();
+  inv_lbreaks[newlines+1] = out;
+  cursor_linenum = lb_linenum;
+
+  /* C_POS == position in buffer where cursor should be placed.
+     CURSOR_LINENUM == line number where the cursor should be placed. */
+
+  /* PWP: now is when things get a bit hairy.  The visible and invisible
+     line buffers are really multiple lines, which would wrap every
+     (screenwidth - 1) characters.  Go through each in turn, finding
+     the changed region and updating it.  The line order is top to bottom. */
+
+  /* If we can move the cursor up and down, then use multiple lines,
+     otherwise, let long lines display in a single terminal line, and
+     horizontally scroll it. */
+
+  if (_rl_horizontal_scroll_mode == 0 && _rl_term_up && *_rl_term_up)
+    {
+      int nleft, pos, changed_screen_line;
+
+      if (!rl_display_fixed || forced_display)
+	{
+	  forced_display = 0;
+
+	  /* If we have more than a screenful of material to display, then
+	     only display a screenful.  We should display the last screen,
+	     not the first.  */
+	  if (out >= _rl_screenchars)
+	    out = _rl_screenchars - 1;
+
+	  /* The first line is at character position 0 in the buffer.  The
+	     second and subsequent lines start at inv_lbreaks[N], offset by
+	     OFFSET (which has already been calculated above).  */
+
+#define W_OFFSET(line, offset) ((line) == 0 ? offset : 0)
+#define VIS_LLEN(l)	((l) > _rl_vis_botlin ? 0 : (vis_lbreaks[l+1] - vis_lbreaks[l]))
+#define INV_LLEN(l)	(inv_lbreaks[l+1] - inv_lbreaks[l])
+#define VIS_CHARS(line) (visible_line + vis_lbreaks[line])
+#define VIS_LINE(line) ((line) > _rl_vis_botlin) ? "" : VIS_CHARS(line)
+#define INV_LINE(line) (invisible_line + inv_lbreaks[line])
+
+	  /* For each line in the buffer, do the updating display. */
+	  for (linenum = 0; linenum <= inv_botlin; linenum++)
+	    {
+	      update_line (VIS_LINE(linenum), INV_LINE(linenum), linenum,
+			   VIS_LLEN(linenum), INV_LLEN(linenum), inv_botlin);
+
+	      /* If this is the line with the prompt, we might need to
+		 compensate for invisible characters in the new line. Do
+		 this only if there is not more than one new line (which
+		 implies that we completely overwrite the old visible line)
+		 and the new line is shorter than the old.  Make sure we are
+		 at the end of the new line before clearing. */
+	      if (linenum == 0 &&
+		  inv_botlin == 0 && _rl_last_c_pos == out &&
+		  (wrap_offset > visible_wrap_offset) &&
+		  (_rl_last_c_pos < visible_first_line_len))
+		{
+		  nleft = _rl_screenwidth + wrap_offset - _rl_last_c_pos;
+		  if (nleft)
+		    _rl_clear_to_eol (nleft);
+		}
+
+	      /* Since the new first line is now visible, save its length. */
+	      if (linenum == 0)
+		visible_first_line_len = (inv_botlin > 0) ? inv_lbreaks[1] : out - wrap_offset;
+	    }
+
+	  /* We may have deleted some lines.  If so, clear the left over
+	     blank ones at the bottom out. */
+	  if (_rl_vis_botlin > inv_botlin)
+	    {
+	      char *tt;
+	      for (; linenum <= _rl_vis_botlin; linenum++)
+		{
+		  tt = VIS_CHARS (linenum);
+		  _rl_move_vert (linenum);
+		  _rl_move_cursor_relative (0, tt);
+		  _rl_clear_to_eol
+		    ((linenum == _rl_vis_botlin) ? strlen (tt) : _rl_screenwidth);
+		}
+	    }
+	  _rl_vis_botlin = inv_botlin;
+
+	  /* CHANGED_SCREEN_LINE is set to 1 if we have moved to a
+	     different screen line during this redisplay. */
+	  changed_screen_line = _rl_last_v_pos != cursor_linenum;
+	  if (changed_screen_line)
+	    {
+	      _rl_move_vert (cursor_linenum);
+	      /* If we moved up to the line with the prompt using _rl_term_up,
+		 the physical cursor position on the screen stays the same,
+		 but the buffer position needs to be adjusted to account
+		 for invisible characters. */
+	      if (cursor_linenum == 0 && wrap_offset)
+		_rl_last_c_pos += wrap_offset;
+	    }
+
+	  /* We have to reprint the prompt if it contains invisible
+	     characters, since it's not generally OK to just reprint
+	     the characters from the current cursor position.  But we
+	     only need to reprint it if the cursor is before the last
+	     invisible character in the prompt string. */
+	  nleft = prompt_visible_length + wrap_offset;
+	  if (cursor_linenum == 0 && wrap_offset > 0 && _rl_last_c_pos > 0 &&
+	      _rl_last_c_pos <= prompt_last_invisible && local_prompt)
+	    {
+#if defined (__MSDOS__)
+	      putc ('\r', rl_outstream);
+#else
+	      if (_rl_term_cr)
+		tputs (_rl_term_cr, 1, _rl_output_character_function);
+#endif
+	      _rl_output_some_chars (local_prompt, nleft);
+	      _rl_last_c_pos = nleft;
+	    }
+
+	  /* Where on that line?  And where does that line start
+	     in the buffer? */
+	  pos = inv_lbreaks[cursor_linenum];
+	  /* nleft == number of characters in the line buffer between the
+	     start of the line and the cursor position. */
+	  nleft = c_pos - pos;
+
+	  /* Since _rl_backspace() doesn't know about invisible characters in the
+	     prompt, and there's no good way to tell it, we compensate for
+	     those characters here and call _rl_backspace() directly. */
+	  if (wrap_offset && cursor_linenum == 0 && nleft < _rl_last_c_pos)
+	    {
+	      _rl_backspace (_rl_last_c_pos - nleft);
+	      _rl_last_c_pos = nleft;
+	    }
+
+	  if (nleft != _rl_last_c_pos)
+	    _rl_move_cursor_relative (nleft, &invisible_line[pos]);
+	}
+    }
+  else				/* Do horizontal scrolling. */
+    {
+#define M_OFFSET(margin, offset) ((margin) == 0 ? offset : 0)
+      int lmargin, ndisp, nleft, phys_c_pos, t;
+
+      /* Always at top line. */
+      _rl_last_v_pos = 0;
+
+      /* Compute where in the buffer the displayed line should start.  This
+	 will be LMARGIN. */
+
+      /* The number of characters that will be displayed before the cursor. */
+      ndisp = c_pos - wrap_offset;
+      nleft  = prompt_visible_length + wrap_offset;
+      /* Where the new cursor position will be on the screen.  This can be
+	 longer than SCREENWIDTH; if it is, lmargin will be adjusted. */
+      phys_c_pos = c_pos - (last_lmargin ? last_lmargin : wrap_offset);
+      t = _rl_screenwidth / 3;
+
+      /* If the number of characters had already exceeded the screenwidth,
+	 last_lmargin will be > 0. */
+
+      /* If the number of characters to be displayed is more than the screen
+	 width, compute the starting offset so that the cursor is about
+	 two-thirds of the way across the screen. */
+      if (phys_c_pos > _rl_screenwidth - 2)
+	{
+	  lmargin = c_pos - (2 * t);
+	  if (lmargin < 0)
+	    lmargin = 0;
+	  /* If the left margin would be in the middle of a prompt with
+	     invisible characters, don't display the prompt at all. */
+	  if (wrap_offset && lmargin > 0 && lmargin < nleft)
+	    lmargin = nleft;
+	}
+      else if (ndisp < _rl_screenwidth - 2)		/* XXX - was -1 */
+	lmargin = 0;
+      else if (phys_c_pos < 1)
+	{
+	  /* If we are moving back towards the beginning of the line and
+	     the last margin is no longer correct, compute a new one. */
+	  lmargin = ((c_pos - 1) / t) * t;	/* XXX */
+	  if (wrap_offset && lmargin > 0 && lmargin < nleft)
+	    lmargin = nleft;
+	}
+      else
+	lmargin = last_lmargin;
+
+      /* If the first character on the screen isn't the first character
+	 in the display line, indicate this with a special character. */
+      if (lmargin > 0)
+	line[lmargin] = '<';
+
+      /* If SCREENWIDTH characters starting at LMARGIN do not encompass
+	 the whole line, indicate that with a special character at the
+	 right edge of the screen.  If LMARGIN is 0, we need to take the
+	 wrap offset into account. */
+      t = lmargin + M_OFFSET (lmargin, wrap_offset) + _rl_screenwidth;
+      if (t < out)
+	line[t - 1] = '>';
+
+      if (!rl_display_fixed || forced_display || lmargin != last_lmargin)
+	{
+	  forced_display = 0;
+	  update_line (&visible_line[last_lmargin],
+		       &invisible_line[lmargin],
+		       0,
+		       _rl_screenwidth + visible_wrap_offset,
+		       _rl_screenwidth + (lmargin ? 0 : wrap_offset),
+		       0);
+
+	  /* If the visible new line is shorter than the old, but the number
+	     of invisible characters is greater, and we are at the end of
+	     the new line, we need to clear to eol. */
+	  t = _rl_last_c_pos - M_OFFSET (lmargin, wrap_offset);
+	  if ((M_OFFSET (lmargin, wrap_offset) > visible_wrap_offset) &&
+	      (_rl_last_c_pos == out) &&
+	      t < visible_first_line_len)
+	    {
+	      nleft = _rl_screenwidth - t;
+	      _rl_clear_to_eol (nleft);
+	    }
+	  visible_first_line_len = out - lmargin - M_OFFSET (lmargin, wrap_offset);
+	  if (visible_first_line_len > _rl_screenwidth)
+	    visible_first_line_len = _rl_screenwidth;
+
+	  _rl_move_cursor_relative (c_pos - lmargin, &invisible_line[lmargin]);
+	  last_lmargin = lmargin;
+	}
+    }
+  fflush (rl_outstream);
+
+  /* Swap visible and non-visible lines. */
+  {
+    char *vtemp = visible_line;
+    int *itemp = vis_lbreaks, ntemp = vis_lbsize;
+
+    visible_line = invisible_line;
+    invisible_line = vtemp;
+
+    vis_lbreaks = inv_lbreaks;
+    inv_lbreaks = itemp;
+
+    vis_lbsize = inv_lbsize;
+    inv_lbsize = ntemp;
+
+    rl_display_fixed = 0;
+    /* If we are displaying on a single line, and last_lmargin is > 0, we
+       are not displaying any invisible characters, so set visible_wrap_offset
+       to 0. */
+    if (_rl_horizontal_scroll_mode && last_lmargin)
+      visible_wrap_offset = 0;
+    else
+      visible_wrap_offset = wrap_offset;
+  }
+}
+
+/* PWP: update_line() is based on finding the middle difference of each
+   line on the screen; vis:
+
+			     /old first difference
+	/beginning of line   |	      /old last same       /old EOL
+	v		     v	      v		    v
+old:	eddie> Oh, my little gruntle-buggy is to me, as lurgid as
+new:	eddie> Oh, my little buggy says to me, as lurgid as
+	^		     ^	^			   ^
+	\beginning of line   |	\new last same	   \new end of line
+			     \new first difference
+
+   All are character pointers for the sake of speed.  Special cases for
+   no differences, as well as for end of line additions must be handled.
+
+   Could be made even smarter, but this works well enough */
+static void
+update_line (old, new, current_line, omax, nmax, inv_botlin)
+     register char *old, *new;
+     int current_line, omax, nmax, inv_botlin;
+{
+  register char *ofd, *ols, *oe, *nfd, *nls, *ne;
+  int temp, lendiff, wsatend, od, nd;
+  int current_invis_chars;
+
+  /* If we're at the right edge of a terminal that supports xn, we're
+     ready to wrap around, so do so.  This fixes problems with knowing
+     the exact cursor position and cut-and-paste with certain terminal
+     emulators.  In this calculation, TEMP is the physical screen
+     position of the cursor. */
+  temp = _rl_last_c_pos - W_OFFSET(_rl_last_v_pos, visible_wrap_offset);
+  if (temp == _rl_screenwidth && _rl_term_autowrap && !_rl_horizontal_scroll_mode
+      && _rl_last_v_pos == current_line - 1)
+    {
+      if (new[0])
+	putc (new[0], rl_outstream);
+      else
+	putc (' ', rl_outstream);
+      _rl_last_c_pos = 1;		/* XXX */
+      _rl_last_v_pos++;
+      if (old[0] && new[0])
+	old[0] = new[0];
+    }
+      
+  /* Find first difference. */
+  for (ofd = old, nfd = new;
+       (ofd - old < omax) && *ofd && (*ofd == *nfd);
+       ofd++, nfd++)
+    ;
+
+  /* Move to the end of the screen line.  ND and OD are used to keep track
+     of the distance between ne and new and oe and old, respectively, to
+     move a subtraction out of each loop. */
+  for (od = ofd - old, oe = ofd; od < omax && *oe; oe++, od++);
+  for (nd = nfd - new, ne = nfd; nd < nmax && *ne; ne++, nd++);
+
+  /* If no difference, continue to next line. */
+  if (ofd == oe && nfd == ne)
+    return;
+
+  wsatend = 1;			/* flag for trailing whitespace */
+  ols = oe - 1;			/* find last same */
+  nls = ne - 1;
+  while ((ols > ofd) && (nls > nfd) && (*ols == *nls))
+    {
+      if (*ols != ' ')
+	wsatend = 0;
+      ols--;
+      nls--;
+    }
+
+  if (wsatend)
+    {
+      ols = oe;
+      nls = ne;
+    }
+  else if (*ols != *nls)
+    {
+      if (*ols)			/* don't step past the NUL */
+	ols++;
+      if (*nls)
+	nls++;
+    }
+
+  /* count of invisible characters in the current invisible line. */
+  current_invis_chars = W_OFFSET (current_line, wrap_offset);
+  if (_rl_last_v_pos != current_line)
+    {
+      _rl_move_vert (current_line);
+      if (current_line == 0 && visible_wrap_offset)
+	_rl_last_c_pos += visible_wrap_offset;
+    }
+
+  /* If this is the first line and there are invisible characters in the
+     prompt string, and the prompt string has not changed, and the current
+     cursor position is before the last invisible character in the prompt,
+     and the index of the character to move to is past the end of the prompt
+     string, then redraw the entire prompt string.  We can only do this
+     reliably if the terminal supports a `cr' capability.
+
+     This is not an efficiency hack -- there is a problem with redrawing
+     portions of the prompt string if they contain terminal escape
+     sequences (like drawing the `unbold' sequence without a corresponding
+     `bold') that manifests itself on certain terminals. */
+
+  lendiff = local_prompt ? strlen (local_prompt) : 0;
+  od = ofd - old;	/* index of first difference in visible line */
+  if (current_line == 0 && !_rl_horizontal_scroll_mode &&
+      _rl_term_cr && lendiff > prompt_visible_length && _rl_last_c_pos > 0 &&
+      od >= lendiff && _rl_last_c_pos <= prompt_last_invisible)
+    {
+#if defined (__MSDOS__)
+      putc ('\r', rl_outstream);
+#else
+      tputs (_rl_term_cr, 1, _rl_output_character_function);
+#endif
+      _rl_output_some_chars (local_prompt, lendiff);
+      _rl_last_c_pos = lendiff;
+    }
+
+  _rl_move_cursor_relative (od, old);
+
+  /* if (len (new) > len (old)) */
+  lendiff = (nls - nfd) - (ols - ofd);
+
+  /* If we are changing the number of invisible characters in a line, and
+     the spot of first difference is before the end of the invisible chars,
+     lendiff needs to be adjusted. */
+  if (current_line == 0 && !_rl_horizontal_scroll_mode &&
+      current_invis_chars != visible_wrap_offset)
+    lendiff += visible_wrap_offset - current_invis_chars;
+
+  /* Insert (diff (len (old), len (new)) ch. */
+  temp = ne - nfd;
+  if (lendiff > 0)
+    {
+      /* Non-zero if we're increasing the number of lines. */
+      int gl = current_line >= _rl_vis_botlin && inv_botlin > _rl_vis_botlin;
+      /* Sometimes it is cheaper to print the characters rather than
+	 use the terminal's capabilities.  If we're growing the number
+	 of lines, make sure we actually cause the new line to wrap
+	 around on auto-wrapping terminals. */
+      if (_rl_terminal_can_insert && ((2 * temp) >= lendiff || _rl_term_IC) && (!_rl_term_autowrap || !gl))
+	{
+	  /* If lendiff > prompt_visible_length and _rl_last_c_pos == 0 and
+	     _rl_horizontal_scroll_mode == 1, inserting the characters with
+	     _rl_term_IC or _rl_term_ic will screw up the screen because of the
+	     invisible characters.  We need to just draw them. */
+	  if (*ols && (!_rl_horizontal_scroll_mode || _rl_last_c_pos > 0 ||
+			lendiff <= prompt_visible_length || !current_invis_chars))
+	    {
+	      insert_some_chars (nfd, lendiff);
+	      _rl_last_c_pos += lendiff;
+	    }
+	  else if (*ols == 0)
+	    {
+	      /* At the end of a line the characters do not have to
+		 be "inserted".  They can just be placed on the screen. */
+	      /* However, this screws up the rest of this block, which
+		 assumes you've done the insert because you can. */
+	      _rl_output_some_chars (nfd, lendiff);
+	      _rl_last_c_pos += lendiff;
+	    }
+	  else
+	    {
+	      /* We have horizontal scrolling and we are not inserting at
+		 the end.  We have invisible characters in this line.  This
+		 is a dumb update. */
+	      _rl_output_some_chars (nfd, temp);
+	      _rl_last_c_pos += temp;
+	      return;
+	    }
+	  /* Copy (new) chars to screen from first diff to last match. */
+	  temp = nls - nfd;
+	  if ((temp - lendiff) > 0)
+	    {
+	      _rl_output_some_chars (nfd + lendiff, temp - lendiff);
+	      _rl_last_c_pos += temp - lendiff;
+	    }
+	}
+      else
+	{
+	  /* cannot insert chars, write to EOL */
+	  _rl_output_some_chars (nfd, temp);
+	  _rl_last_c_pos += temp;
+	}
+    }
+  else				/* Delete characters from line. */
+    {
+      /* If possible and inexpensive to use terminal deletion, then do so. */
+      if (_rl_term_dc && (2 * temp) >= -lendiff)
+	{
+	  /* If all we're doing is erasing the invisible characters in the
+	     prompt string, don't bother.  It screws up the assumptions
+	     about what's on the screen. */
+	  if (_rl_horizontal_scroll_mode && _rl_last_c_pos == 0 &&
+	      -lendiff == visible_wrap_offset)
+	    lendiff = 0;
+
+	  if (lendiff)
+	    delete_chars (-lendiff); /* delete (diff) characters */
+
+	  /* Copy (new) chars to screen from first diff to last match */
+	  temp = nls - nfd;
+	  if (temp > 0)
+	    {
+	      _rl_output_some_chars (nfd, temp);
+	      _rl_last_c_pos += temp;
+	    }
+	}
+      /* Otherwise, print over the existing material. */
+      else
+	{
+	  if (temp > 0)
+	    {
+	      _rl_output_some_chars (nfd, temp);
+	      _rl_last_c_pos += temp;
+	    }
+	  lendiff = (oe - old) - (ne - new);
+	  if (lendiff)
+	    {	  
+	      if (_rl_term_autowrap && current_line < inv_botlin)
+		space_to_eol (lendiff);
+	      else
+		_rl_clear_to_eol (lendiff);
+	    }
+	}
+    }
+}
+
+/* Tell the update routines that we have moved onto a new (empty) line. */
+int
+rl_on_new_line ()
+{
+  if (visible_line)
+    visible_line[0] = '\0';
+
+  _rl_last_c_pos = _rl_last_v_pos = 0;
+  _rl_vis_botlin = last_lmargin = 0;
+  if (vis_lbreaks)
+    vis_lbreaks[0] = vis_lbreaks[1] = 0;
+  visible_wrap_offset = 0;
+  return 0;
+}
+
+/* Tell the update routines that we have moved onto a new line with the
+   prompt already displayed.  Code originally from the version of readline
+   distributed with CLISP. */
+int
+rl_on_new_line_with_prompt ()
+{
+  int prompt_size, i, l, real_screenwidth, newlines;
+  char *prompt_last_line;
+
+  /* Initialize visible_line and invisible_line to ensure that they can hold
+     the already-displayed prompt. */
+  prompt_size = strlen (rl_prompt) + 1;
+  init_line_structures (prompt_size);
+
+  /* Make sure the line structures hold the already-displayed prompt for
+     redisplay. */
+  strcpy (visible_line, rl_prompt);
+  strcpy (invisible_line, rl_prompt);
+
+  /* If the prompt contains newlines, take the last tail. */
+  prompt_last_line = strrchr (rl_prompt, '\n');
+  if (!prompt_last_line)
+    prompt_last_line = rl_prompt;
+
+  l = strlen (prompt_last_line);
+  _rl_last_c_pos = l;
+
+  /* Dissect prompt_last_line into screen lines. Note that here we have
+     to use the real screenwidth. Readline's notion of screenwidth might be
+     one less, see terminal.c. */
+  real_screenwidth = _rl_screenwidth + (_rl_term_autowrap ? 0 : 1);
+  _rl_last_v_pos = l / real_screenwidth;
+  /* If the prompt length is a multiple of real_screenwidth, we don't know
+     whether the cursor is at the end of the last line, or already at the
+     beginning of the next line. Output a newline just to be safe. */
+  if (l > 0 && (l % real_screenwidth) == 0)
+    _rl_output_some_chars ("\n", 1);
+  last_lmargin = 0;
+
+  newlines = 0; i = 0;
+  while (i <= l)
+    {
+      _rl_vis_botlin = newlines;
+      vis_lbreaks[newlines++] = i;
+      i += real_screenwidth;
+    }
+  vis_lbreaks[newlines] = l;
+  visible_wrap_offset = 0;
+
+  return 0;
+}
+
+/* Actually update the display, period. */
+int
+rl_forced_update_display ()
+{
+  if (visible_line)
+    {
+      register char *temp = visible_line;
+
+      while (*temp)
+	*temp++ = '\0';
+    }
+  rl_on_new_line ();
+  forced_display++;
+  (*rl_redisplay_function) ();
+  return 0;
+}
+
+/* Move the cursor from _rl_last_c_pos to NEW, which are buffer indices.
+   DATA is the contents of the screen line of interest; i.e., where
+   the movement is being done. */
+void
+_rl_move_cursor_relative (new, data)
+     int new;
+     const char *data;
+{
+  register int i;
+
+  /* If we don't have to do anything, then return. */
+  if (_rl_last_c_pos == new) return;
+
+  /* It may be faster to output a CR, and then move forwards instead
+     of moving backwards. */
+  /* i == current physical cursor position. */
+  i = _rl_last_c_pos - W_OFFSET(_rl_last_v_pos, visible_wrap_offset);
+  if (new == 0 || CR_FASTER (new, _rl_last_c_pos) ||
+      (_rl_term_autowrap && i == _rl_screenwidth))
+    {
+#if defined (__MSDOS__)
+      putc ('\r', rl_outstream);
+#else
+      tputs (_rl_term_cr, 1, _rl_output_character_function);
+#endif /* !__MSDOS__ */
+      _rl_last_c_pos = 0;
+    }
+
+  if (_rl_last_c_pos < new)
+    {
+      /* Move the cursor forward.  We do it by printing the command
+	 to move the cursor forward if there is one, else print that
+	 portion of the output buffer again.  Which is cheaper? */
+
+      /* The above comment is left here for posterity.  It is faster
+	 to print one character (non-control) than to print a control
+	 sequence telling the terminal to move forward one character.
+	 That kind of control is for people who don't know what the
+	 data is underneath the cursor. */
+#if defined (HACK_TERMCAP_MOTION)
+      if (_rl_term_forward_char)
+	for (i = _rl_last_c_pos; i < new; i++)
+	  tputs (_rl_term_forward_char, 1, _rl_output_character_function);
+      else
+	for (i = _rl_last_c_pos; i < new; i++)
+	  putc (data[i], rl_outstream);
+#else
+      for (i = _rl_last_c_pos; i < new; i++)
+	putc (data[i], rl_outstream);
+#endif /* HACK_TERMCAP_MOTION */
+    }
+  else if (_rl_last_c_pos > new)
+    _rl_backspace (_rl_last_c_pos - new);
+  _rl_last_c_pos = new;
+}
+
+/* PWP: move the cursor up or down. */
+void
+_rl_move_vert (to)
+     int to;
+{
+  register int delta, i;
+
+  if (_rl_last_v_pos == to || to > _rl_screenheight)
+    return;
+
+  if ((delta = to - _rl_last_v_pos) > 0)
+    {
+      for (i = 0; i < delta; i++)
+	putc ('\n', rl_outstream);
+#if defined (__MSDOS__)
+      putc ('\r', rl_outstream);
+#else
+      tputs (_rl_term_cr, 1, _rl_output_character_function);
+#endif
+      _rl_last_c_pos = 0;
+    }
+  else
+    {			/* delta < 0 */
+      if (_rl_term_up && *_rl_term_up)
+	for (i = 0; i < -delta; i++)
+	  tputs (_rl_term_up, 1, _rl_output_character_function);
+    }
+
+  _rl_last_v_pos = to;		/* Now TO is here */
+}
+
+/* Physically print C on rl_outstream.  This is for functions which know
+   how to optimize the display.  Return the number of characters output. */
+int
+rl_show_char (c)
+     int c;
+{
+  int n = 1;
+  if (META_CHAR (c) && (_rl_output_meta_chars == 0))
+    {
+      fprintf (rl_outstream, "M-");
+      n += 2;
+      c = UNMETA (c);
+    }
+
+#if defined (DISPLAY_TABS)
+  if ((CTRL_CHAR (c) && c != '\t') || c == RUBOUT)
+#else
+  if (CTRL_CHAR (c) || c == RUBOUT)
+#endif /* !DISPLAY_TABS */
+    {
+      fprintf (rl_outstream, "C-");
+      n += 2;
+      c = CTRL_CHAR (c) ? UNCTRL (c) : '?';
+    }
+
+  putc (c, rl_outstream);
+  fflush (rl_outstream);
+  return n;
+}
+
+int
+rl_character_len (c, pos)
+     register int c, pos;
+{
+  unsigned char uc;
+
+  uc = (unsigned char)c;
+
+  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 = prompt_last_invisible;
+  saved_visible_length = prompt_visible_length;
+
+  local_prompt = local_prompt_prefix = (char *)0;
+  prompt_last_invisible = prompt_visible_length = 0;
+}
+
+void
+rl_restore_prompt ()
+{
+  FREE (local_prompt);
+  FREE (local_prompt_prefix);
+
+  local_prompt = saved_local_prompt;
+  local_prompt_prefix = saved_local_prefix;
+  prompt_last_invisible = saved_last_invisible;
+  prompt_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);
+      prompt_last_invisible = saved_last_invisible;
+      prompt_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 (_rl_term_clreol)
+    tputs (_rl_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 ()
+{
+  if (_rl_term_clrpag)
+    tputs (_rl_term_clrpag, 1, _rl_output_character_function);
+  else
+    rl_crlf ();
+}
+
+/* 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 (_rl_term_IC)
+    {
+      char *buffer;
+      buffer = tgoto (_rl_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 (_rl_term_im && *_rl_term_im)
+	tputs (_rl_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 (_rl_term_ic && *_rl_term_ic)
+	{
+	  for (i = count; i--; )
+	    tputs (_rl_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 (_rl_term_ei && *_rl_term_ei)
+	tputs (_rl_term_ei, 1, _rl_output_character_function);
+    }
+}
+
+/* Delete COUNT characters from the display line. */
+static void
+delete_chars (count)
+     int count;
+{
+  if (count > _rl_screenwidth)	/* XXX */
+    return;
+
+  if (_rl_term_DC && *_rl_term_DC)
+    {
+      char *buffer;
+      buffer = tgoto (_rl_term_DC, count, count);
+      tputs (buffer, count, _rl_output_character_function);
+    }
+  else
+    {
+      if (_rl_term_dc && *_rl_term_dc)
+	while (count--)
+	  tputs (_rl_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) == _rl_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 (_rl_screenwidth - 1, last_line);
+      _rl_clear_to_eol (0);
+      putc (last_line[_rl_screenwidth - 1], rl_outstream);
+    }
+  _rl_vis_botlin = 0;
+  rl_crlf ();
+  fflush (rl_outstream);
+  rl_display_fixed++;
+}
+
+/* Move to the start of the current line. */
+static void
+cr ()
+{
+  if (_rl_term_cr)
+    {
+#if defined (__MSDOS__)
+      putc ('\r', rl_outstream);
+#else
+      tputs (_rl_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, oldninvis;
+
+  /* Geez, I should make this a struct. */
+  oldp = rl_display_prompt;
+  oldl = local_prompt;
+  oldlprefix = local_prompt_prefix;
+  oldlen = prompt_visible_length;
+  oldplen = prompt_prefix_length;
+  oldlast = prompt_last_invisible;
+  oldninvis = prompt_invis_chars_first_line;
+
+  rl_display_prompt = t;
+  local_prompt = expand_prompt (t, &prompt_visible_length,
+				   &prompt_last_invisible,
+				   &prompt_invis_chars_first_line);
+  local_prompt_prefix = (char *)NULL;
+  rl_forced_update_display ();
+
+  rl_display_prompt = oldp;
+  local_prompt = oldl;
+  local_prompt_prefix = oldlprefix;
+  prompt_visible_length = oldlen;
+  prompt_prefix_length = oldplen;
+  prompt_last_invisible = oldlast;
+  prompt_invis_chars_first_line = oldninvis;
+}
+      
+/* 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 (_rl_term_cr)
+    {
+#if defined (__MSDOS__)
+      putc ('\r', rl_outstream);
+#else
+      tputs (_rl_term_cr, 1, _rl_output_character_function);
+#endif
+      _rl_last_c_pos = 0;
+#if defined (__MSDOS__)
+      space_to_eol (_rl_screenwidth);
+      putc ('\r', rl_outstream);
+#else
+      if (_rl_term_clreol)
+	tputs (_rl_term_clreol, 1, _rl_output_character_function);
+      else
+	{
+	  space_to_eol (_rl_screenwidth);
+	  tputs (_rl_term_cr, 1, _rl_output_character_function);
+	}
+#endif
+      if (_rl_last_v_pos > 0)
+	_rl_move_vert (0);
+    }
+  else
+    rl_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 - _rl_screenwidth - rl_visible_prompt_length;
+  else
+    nleft = _rl_last_c_pos - _rl_screenwidth;
+
+  if (nleft > 0)
+    ret = 1 + nleft / _rl_screenwidth;
+  else
+    ret = 0;
+
+  return ret;
+}