BSD 4.4 Lite Lib Sources

1 files changed, 1013 insertions, 0 deletions

diff --git a/lib/libedit/refresh.c b/lib/libedit/refresh.c
new file mode 100644
index 0000000..b64d011
--- /dev/null
+++ b/lib/libedit/refresh.c
@@ -0,0 +1,1013 @@
+/*-
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Christos Zoulas of Cornell University.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if !defined(lint) && !defined(SCCSID)
+static char sccsid[] = "@(#)refresh.c	8.1 (Berkeley) 6/4/93";
+#endif /* not lint && not SCCSID */
+
+/*
+ * refresh.c: Lower level screen refreshing functions
+ */
+#include "sys.h"
+#include <stdio.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <string.h>
+
+#include "el.h"
+
+private	void	re_addc 		__P((EditLine *, int));
+private	void	re_update_line 		__P((EditLine *, char *, char *, int));
+private	void	re_insert		__P((EditLine *, char *, int, int, 
+					     char *, int));
+private	void	re_delete		__P((EditLine *, char *, int, int, 
+					     int));
+private	void	re_fastputc		__P((EditLine *, int));
+
+private	void	re__strncopy		__P((char *, char *, size_t));
+private	void	re__copy_and_pad	__P((char *, char *, size_t));
+
+#ifdef DEBUG_REFRESH
+private	void	re_printstr		__P((EditLine *, char *, char *, 
+					     char *));
+# define __F el->el_errfile
+# define RE_DEBUG(a, b, c)	do 				\
+				    if (a) {			\
+					(void) fprintf b;	\
+					c;			\
+				    }				\
+				while (0)
+/* re_printstr():
+ *	Print a string on the debugging pty
+ */
+private void
+re_printstr(el, str, f, t)
+    EditLine *el;
+    char *str;
+    char *f, *t;
+{
+    RE_DEBUG(1,(__F, "%s:\"", str),);
+    while (f < t)
+	RE_DEBUG(1,(__F, "%c", *f++ & 0177),);
+    RE_DEBUG(1,(__F, "\"\r\n"),);
+} 
+#else
+# define RE_DEBUG(a, b, c)
+#endif
+
+
+/* re_addc():
+ *	Draw c, expanding tabs, control chars etc.
+ */
+private void
+re_addc(el, c)
+    EditLine *el;
+    int c;
+{
+    if (isprint(c)) {
+	re_putc(el, c);
+	return;
+    }
+    if (c == '\n') {			/* expand the newline	 */
+	re_putc(el, '\0');		/* assure end of line	 */
+	el->el_refresh.r_cursor.h = 0;	/* reset cursor pos	 */
+	el->el_refresh.r_cursor.v++;
+	return;
+    }
+    if (c == '\t') {		/* expand the tab 	 */
+	for (;;) {
+	    re_putc(el, ' ');
+	    if ((el->el_refresh.r_cursor.h & 07) == 0)
+		break;		/* go until tab stop	 */
+	}
+    }
+    else if (iscntrl(c)) {
+	re_putc(el, '^');
+	if (c == '\177') 
+	    re_putc(el, '?');
+	else 
+	    /* uncontrolify it; works only for iso8859-1 like sets */
+	    re_putc(el, (c | 0100));
+    }
+    else {
+	re_putc(el, '\\');
+	re_putc(el, ((c >> 6) & 07) + '0');
+	re_putc(el, ((c >> 3) & 07) + '0');
+	re_putc(el, (c & 07) + '0');
+    }
+} /* end re_addc */
+
+
+/* re_putc():
+ *	Draw the character given
+ */
+protected void
+re_putc(el, c)
+    EditLine *el;
+    int c;
+{
+    RE_DEBUG(1,(__F, "printing %3.3o '%c'\r\n", c, c),);
+
+    el->el_vdisplay[el->el_refresh.r_cursor.v][el->el_refresh.r_cursor.h] = c;
+    el->el_refresh.r_cursor.h++;				/* advance to next place */
+    if (el->el_refresh.r_cursor.h >= el->el_term.t_size.h) {
+	el->el_vdisplay[el->el_refresh.r_cursor.v][el->el_term.t_size.h] = '\0';	
+						/* assure end of line */
+	el->el_refresh.r_cursor.h = 0;				/* reset it. */
+	el->el_refresh.r_cursor.v++;
+	RE_DEBUG(el->el_refresh.r_cursor.v >= el->el_term.t_size.v, 
+		 (__F, "\r\nre_putc: overflow! r_cursor.v == %d > %d\r\n",
+		  el->el_refresh.r_cursor.v, el->el_term.t_size.v), abort());
+    }
+} /* end re_putc */
+
+
+/* re_refresh():
+ *	draws the new virtual screen image from the current input
+ *  	line, then goes line-by-line changing the real image to the new
+ *	virtual image. The routine to re-draw a line can be replaced
+ *	easily in hopes of a smarter one being placed there.
+ */
+protected void
+re_refresh(el)
+    EditLine *el;
+{
+    int i;
+    char *cp;
+    coord_t     cur;
+
+    RE_DEBUG(1,(__F, "el->el_line.buffer = :%s:\r\n", el->el_line.buffer),);
+
+    /* reset the Drawing cursor */
+    el->el_refresh.r_cursor.h = 0;
+    el->el_refresh.r_cursor.v = 0;
+
+    cur.h = -1;			/* set flag in case I'm not set */
+    cur.v = 0;
+
+    prompt_print(el);
+
+    /* draw the current input buffer */
+    for (cp = el->el_line.buffer; cp < el->el_line.lastchar; cp++) {
+	if (cp == el->el_line.cursor) {
+	    cur.h = el->el_refresh.r_cursor.h;	/* save for later */
+	    cur.v = el->el_refresh.r_cursor.v;
+	}
+	re_addc(el, *cp);
+    }
+
+    if (cur.h == -1) {		/* if I haven't been set yet, I'm at the end */
+	cur.h = el->el_refresh.r_cursor.h;
+	cur.v = el->el_refresh.r_cursor.v;
+    }
+    /* must be done BEFORE the NUL is written */
+    el->el_refresh.r_newcv = el->el_refresh.r_cursor.v;	
+    re_putc(el, '\0');		/* put NUL on end */
+
+    RE_DEBUG(1,(__F, 
+	     "term.h=%d vcur.h=%d vcur.v=%d vdisplay[0]=\r\n:%80.80s:\r\n",
+	     el->el_term.t_size.h, el->el_refresh.r_cursor.h, 
+	     el->el_refresh.r_cursor.v, el->el_vdisplay[0]),);
+
+    RE_DEBUG(1,(__F, "updating %d lines.\r\n", el->el_refresh.r_newcv),);
+    for (i = 0; i <= el->el_refresh.r_newcv; i++) {
+	/* NOTE THAT re_update_line MAY CHANGE el_display[i] */
+	re_update_line(el, el->el_display[i], el->el_vdisplay[i], i);
+
+	/*
+	 * Copy the new line to be the current one, and pad out with spaces
+	 * to the full width of the terminal so that if we try moving the
+	 * cursor by writing the character that is at the end of the
+	 * screen line, it won't be a NUL or some old leftover stuff.
+	 */
+	re__copy_and_pad(el->el_display[i], el->el_vdisplay[i], 
+			el->el_term.t_size.h);
+    }
+    RE_DEBUG(1,(__F,
+	 "\r\nel->el_refresh.r_cursor.v=%d,el->el_refresh.r_oldcv=%d i=%d\r\n",
+	 el->el_refresh.r_cursor.v, el->el_refresh.r_oldcv, i),);
+
+    if (el->el_refresh.r_oldcv > el->el_refresh.r_newcv) 
+	for (; i <= el->el_refresh.r_oldcv; i++) {
+	    term_move_to_line(el, i);
+	    term_move_to_char(el, 0);
+	    term_clear_EOL(el, strlen(el->el_display[i]));
+#ifdef DEBUG_REFRESH
+	    term_overwrite(el, "C\b", 2);
+#endif /* DEBUG_REFRESH */
+	    *el->el_display[i] = '\0';
+	}
+    
+    el->el_refresh.r_oldcv = el->el_refresh.r_newcv;	/* set for next time */
+    RE_DEBUG(1,(__F, 
+		"\r\ncursor.h = %d, cursor.v = %d, cur.h = %d, cur.v = %d\r\n",
+		el->el_refresh.r_cursor.h, el->el_refresh.r_cursor.v, 
+		cur.h, cur.v),);
+    term_move_to_line(el, cur.v);		/* go to where the cursor is */
+    term_move_to_char(el, cur.h);
+} /* end re_refresh */
+
+
+/* re_goto_bottom():
+ *	 used to go to last used screen line 
+ */
+protected void
+re_goto_bottom(el)
+    EditLine *el;
+{
+    term_move_to_line(el, el->el_refresh.r_oldcv);
+    term__putc('\r');
+    term__putc('\n');
+    re_clear_display(el);
+    term__flush();
+} /* end re_goto_bottom */
+
+
+/* re_insert():
+ *	insert num characters of s into d (in front of the character)
+ *	at dat, maximum length of d is dlen 
+ */
+private void
+/*ARGSUSED*/
+re_insert(el, d, dat, dlen, s, num)
+    EditLine *el;
+    char *d;
+    int dat, dlen;
+    char *s;
+    int num;
+{
+    char *a, *b;
+
+    if (num <= 0)
+	return;
+    if (num > dlen - dat)
+	num = dlen - dat;
+
+    RE_DEBUG(1,(__F, "re_insert() starting: %d at %d max %d, d == \"%s\"\n",
+	    num, dat, dlen, d),);
+    RE_DEBUG(1,(__F, "s == \"%s\"n", s),);
+
+    /* open up the space for num chars */
+    if (num > 0) {
+	b = d + dlen - 1;
+	a = b - num;
+	while (a >= &d[dat])
+	    *b-- = *a--;
+	d[dlen] = '\0';		/* just in case */
+    }
+    RE_DEBUG(1,(__F, 
+		"re_insert() after insert: %d at %d max %d, d == \"%s\"\n",
+		num, dat, dlen, d),);
+    RE_DEBUG(1,(__F, "s == \"%s\"n", s),);
+
+    /* copy the characters */
+    for (a = d + dat; (a < d + dlen) && (num > 0); num--)
+	*a++ = *s++;
+
+    RE_DEBUG(1,(__F, "re_insert() after copy: %d at %d max %d, %s == \"%s\"\n",
+	     num, dat, dlen, d, s),);
+    RE_DEBUG(1,(__F, "s == \"%s\"n", s),);
+} /* end re_insert */
+
+
+/* re_delete():
+ *	delete num characters d at dat, maximum length of d is dlen 
+ */
+private void
+/*ARGSUSED*/
+re_delete(el, d, dat, dlen, num)
+    EditLine *el;
+    char *d;
+    int dat, dlen, num;
+{
+    char *a, *b;
+
+    if (num <= 0)
+	return;
+    if (dat + num >= dlen) {
+	d[dat] = '\0';
+	return;
+    }
+
+    RE_DEBUG(1,(__F, "re_delete() starting: %d at %d max %d, d == \"%s\"\n",
+	    num, dat, dlen, d),);
+
+    /* open up the space for num chars */
+    if (num > 0) {
+	b = d + dat;
+	a = b + num;
+	while (a < &d[dlen])
+	    *b++ = *a++;
+	d[dlen] = '\0';		/* just in case */
+    }
+    RE_DEBUG(1,(__F, "re_delete() after delete: %d at %d max %d, d == \"%s\"\n",
+	    num, dat, dlen, d),);
+} /* end re_delete */
+
+
+/* re__strncopy():
+ *	Like strncpy without padding.
+ */
+private void
+re__strncopy(a, b, n)
+    char *a, *b;
+    size_t n;
+{
+    while (n-- && *b)
+	*a++ = *b++;
+} /* end re__strncopy */
+
+
+/* ****************************************************************
+    re_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.
+**************************************************************** */
+
+/* Minimum at which doing an insert it "worth it".  This should be about
+ * half the "cost" of going into insert mode, inserting a character, and
+ * going back out.  This should really be calculated from the termcap
+ * data...  For the moment, a good number for ANSI terminals.
+ */
+#define MIN_END_KEEP	4
+
+private void
+re_update_line(el, old, new, i)
+    EditLine *el;
+    char *old, *new;
+    int     i;
+{
+    char *o, *n, *p, c;
+    char   *ofd, *ols, *oe, *nfd, *nls, *ne;
+    char   *osb, *ose, *nsb, *nse;
+    int     fx, sx;
+
+    /*
+     * find first diff
+     */
+    for (o = old, n = new; *o && (*o == *n); o++, n++)
+	continue;
+    ofd = o;
+    nfd = n;
+
+    /*
+     * Find the end of both old and new
+     */
+    while (*o)
+	o++;
+    /* 
+     * Remove any trailing blanks off of the end, being careful not to
+     * back up past the beginning.
+     */
+    while (ofd < o) {
+	if (o[-1] != ' ')
+	    break;
+	o--;
+    }
+    oe = o;
+    *oe = '\0';
+  
+    while (*n)
+	n++;
+
+    /* remove blanks from end of new */
+    while (nfd < n) {
+	if (n[-1] != ' ')
+	    break;
+	n--;
+    }
+    ne = n;
+    *ne = '\0';
+  
+    /*
+     * if no diff, continue to next line of redraw
+     */
+    if (*ofd == '\0' && *nfd == '\0') {
+	RE_DEBUG(1,(__F, "no difference.\r\n"),);
+	return;
+    }
+
+    /*
+     * find last same pointer
+     */
+    while ((o > ofd) && (n > nfd) && (*--o == *--n))
+	continue;
+    ols = ++o;
+    nls = ++n;
+
+    /*
+     * find same begining and same end
+     */
+    osb = ols;
+    nsb = nls;
+    ose = ols;
+    nse = nls;
+
+    /*
+     * case 1: insert: scan from nfd to nls looking for *ofd
+     */
+    if (*ofd) {
+	for (c = *ofd, n = nfd; n < nls; n++) {
+	    if (c == *n) {
+		for (o = ofd, p = n; p < nls && o < ols && *o == *p; o++, p++)
+		    continue;
+		/*
+		 * if the new match is longer and it's worth keeping, then we
+		 * take it
+		 */
+		if (((nse - nsb) < (p - n)) && (2 * (p - n) > n - nfd)) {
+		    nsb = n;
+		    nse = p;
+		    osb = ofd;
+		    ose = o;
+		}
+	    }
+	}
+    }
+
+    /*
+     * case 2: delete: scan from ofd to ols looking for *nfd
+     */
+    if (*nfd) {
+	for (c = *nfd, o = ofd; o < ols; o++) {
+	    if (c == *o) {
+		for (n = nfd, p = o; p < ols && n < nls && *p == *n; p++, n++)
+		    continue;
+		/*
+		 * if the new match is longer and it's worth keeping, then we
+		 * take it
+		 */
+		if (((ose - osb) < (p - o)) && (2 * (p - o) > o - ofd)) {
+		    nsb = nfd;
+		    nse = n;
+		    osb = o;
+		    ose = p;
+		}
+	    }
+	}
+    }
+
+    /*
+     * Pragmatics I: If old trailing whitespace or not enough characters to
+     * save to be worth it, then don't save the last same info.
+     */
+    if ((oe - ols) < MIN_END_KEEP) {
+	ols = oe;
+	nls = ne;
+    }
+
+    /*
+     * Pragmatics II: if the terminal isn't smart enough, make the data dumber
+     * so the smart update doesn't try anything fancy
+     */
+
+    /*
+     * fx is the number of characters we need to insert/delete: in the
+     * beginning to bring the two same begins together
+     */
+    fx = (nsb - nfd) - (osb - ofd);
+    /*
+     * sx is the number of characters we need to insert/delete: in the end to
+     * bring the two same last parts together
+     */
+    sx = (nls - nse) - (ols - ose);
+
+    if (!EL_CAN_INSERT) {
+	if (fx > 0) {
+	    osb = ols;
+	    ose = ols;
+	    nsb = nls;
+	    nse = nls;
+	}
+	if (sx > 0) {
+	    ols = oe;
+	    nls = ne;
+	}
+	if ((ols - ofd) < (nls - nfd)) {
+	    ols = oe;
+	    nls = ne;
+	}
+    }
+    if (!EL_CAN_DELETE) {
+	if (fx < 0) {
+	    osb = ols;
+	    ose = ols;
+	    nsb = nls;
+	    nse = nls;
+	}
+	if (sx < 0) {
+	    ols = oe;
+	    nls = ne;
+	}
+	if ((ols - ofd) > (nls - nfd)) {
+	    ols = oe;
+	    nls = ne;
+	}
+    }
+
+    /*
+     * Pragmatics III: make sure the middle shifted pointers are correct if
+     * they don't point to anything (we may have moved ols or nls).
+     */
+    /* if the change isn't worth it, don't bother */
+    /* was: if (osb == ose) */
+    if ((ose - osb) < MIN_END_KEEP) {
+	osb = ols;
+	ose = ols;
+	nsb = nls;
+	nse = nls;
+    }
+
+    /*
+     * Now that we are done with pragmatics we recompute fx, sx
+     */
+    fx = (nsb - nfd) - (osb - ofd);
+    sx = (nls - nse) - (ols - ose);
+
+    RE_DEBUG(1,(__F, "\n"),);
+    RE_DEBUG(1,(__F, "ofd %d, osb %d, ose %d, ols %d, oe %d\n",
+	    ofd - old, osb - old, ose - old, ols - old, oe - old),);
+    RE_DEBUG(1,(__F, "nfd %d, nsb %d, nse %d, nls %d, ne %d\n",
+	    nfd - new, nsb - new, nse - new, nls - new, ne - new),);
+    RE_DEBUG(1,(__F, 
+		"xxx-xxx:\"00000000001111111111222222222233333333334\"\r\n"),);
+    RE_DEBUG(1,(__F,
+		"xxx-xxx:\"01234567890123456789012345678901234567890\"\r\n"),);
+#ifdef DEBUG_REFRESH
+    re_printstr(el, "old- oe", old, oe);
+    re_printstr(el, "new- ne", new, ne);
+    re_printstr(el, "old-ofd", old, ofd);
+    re_printstr(el, "new-nfd", new, nfd);
+    re_printstr(el, "ofd-osb", ofd, osb);
+    re_printstr(el, "nfd-nsb", nfd, nsb);
+    re_printstr(el, "osb-ose", osb, ose);
+    re_printstr(el, "nsb-nse", nsb, nse);
+    re_printstr(el, "ose-ols", ose, ols);
+    re_printstr(el, "nse-nls", nse, nls);
+    re_printstr(el, "ols- oe", ols, oe);
+    re_printstr(el, "nls- ne", nls, ne);
+#endif /* DEBUG_REFRESH */
+
+    /*
+     * el_cursor.v to this line i MUST be in this routine so that if we
+     * don't have to change the line, we don't move to it. el_cursor.h to first
+     * diff char
+     */
+    term_move_to_line(el, i);
+
+    /*
+     * at this point we have something like this:
+     * 
+     * /old                  /ofd    /osb               /ose    /ols     /oe
+     * v.....................v       v..................v       v........v
+     * eddie> Oh, my fredded gruntle-buggy is to me, as foo var lurgid as
+     * eddie> Oh, my fredded quiux buggy is to me, as gruntle-lurgid as
+     * ^.....................^     ^..................^       ^........^ 
+     * \new                  \nfd  \nsb               \nse     \nls    \ne
+     * 
+     * fx is the difference in length between the the chars between nfd and
+     * nsb, and the chars between ofd and osb, and is thus the number of
+     * characters to delete if < 0 (new is shorter than old, as above),
+     * or insert (new is longer than short).
+     *
+     * sx is the same for the second differences.
+     */
+
+    /*
+     * if we have a net insert on the first difference, AND inserting the net
+     * amount ((nsb-nfd) - (osb-ofd)) won't push the last useful character
+     * (which is ne if nls != ne, otherwise is nse) off the edge of the screen
+     * (el->el_term.t_size.h) else we do the deletes first so that we keep everything we need
+     * to.
+     */
+
+    /*
+     * if the last same is the same like the end, there is no last same part,
+     * otherwise we want to keep the last same part set p to the last useful
+     * old character
+     */
+    p = (ols != oe) ? oe : ose;
+
+    /*
+     * if (There is a diffence in the beginning) && (we need to insert
+     * characters) && (the number of characters to insert is less than the term
+     * width) We need to do an insert! else if (we need to delete characters)
+     * We need to delete characters! else No insert or delete
+     */
+    if ((nsb != nfd) && fx > 0 && ((p - old) + fx <= el->el_term.t_size.h)) {
+	RE_DEBUG(1,(__F, "first diff insert at %d...\r\n", nfd - new),);
+	/*
+	 * Move to the first char to insert, where the first diff is.
+	 */
+	term_move_to_char(el, nfd - new);
+	/*
+	 * Check if we have stuff to keep at end
+	 */
+	if (nsb != ne) {
+	    RE_DEBUG(1,(__F, "with stuff to keep at end\r\n"),);
+	    /*
+	     * insert fx chars of new starting at nfd
+	     */
+	    if (fx > 0) {
+		RE_DEBUG(!EL_CAN_INSERT,
+			 (__F, "ERROR: cannot insert in early first diff\n"),);
+		term_insertwrite(el, nfd, fx);
+		re_insert(el, old, ofd - old, el->el_term.t_size.h, nfd, fx);
+	    }
+	    /*
+	     * write (nsb-nfd) - fx chars of new starting at (nfd + fx)
+	     */
+	    term_overwrite(el, nfd + fx, (nsb - nfd) - fx);
+	    re__strncopy(ofd + fx, nfd + fx, (nsb - nfd) - fx);
+	}
+	else {
+	    RE_DEBUG(1,(__F, "without anything to save\r\n"),);
+	    term_overwrite(el, nfd, (nsb - nfd));
+	    re__strncopy(ofd, nfd, (nsb - nfd));
+	    /*
+	     * Done
+	     */
+	    return;
+	}
+    }
+    else if (fx < 0) {
+	RE_DEBUG(1,(__F, "first diff delete at %d...\r\n", ofd - old),);
+	/*
+	 * move to the first char to delete where the first diff is
+	 */
+	term_move_to_char(el, ofd - old);
+	/*
+	 * Check if we have stuff to save
+	 */
+	if (osb != oe) {
+	    RE_DEBUG(1,(__F, "with stuff to save at end\r\n"),);
+	    /*
+	     * fx is less than zero *always* here but we check for code
+	     * symmetry
+	     */
+	    if (fx < 0) {
+		RE_DEBUG(!EL_CAN_DELETE,
+			 (__F, "ERROR: cannot delete in first diff\n"),);
+		term_deletechars(el, -fx);
+		re_delete(el, old, ofd - old, el->el_term.t_size.h, -fx);
+	    }
+	    /*
+	     * write (nsb-nfd) chars of new starting at nfd
+	     */
+	    term_overwrite(el, nfd, (nsb - nfd));
+	    re__strncopy(ofd, nfd, (nsb - nfd));
+
+	}
+	else {
+	    RE_DEBUG(1,(__F, "but with nothing left to save\r\n"),);
+	    /*
+	     * write (nsb-nfd) chars of new starting at nfd
+	     */
+	    term_overwrite(el, nfd, (nsb - nfd));
+	    RE_DEBUG(1,(__F, "cleareol %d\n", (oe - old) - (ne - new)),);
+	    term_clear_EOL(el, (oe - old) - (ne - new));
+	    /*
+	     * Done
+	     */
+	    return;
+	}
+    }
+    else
+	fx = 0;
+
+    if (sx < 0) {
+	RE_DEBUG(1,(__F, "second diff delete at %d...\r\n", (ose - old) + fx),);
+	/*
+	 * Check if we have stuff to delete
+	 */
+	/*
+	 * fx is the number of characters inserted (+) or deleted (-)
+	 */
+
+	term_move_to_char(el, (ose - old) + fx);
+	/*
+	 * Check if we have stuff to save
+	 */
+	if (ols != oe) {
+	    RE_DEBUG(1,(__F, "with stuff to save at end\r\n"),);
+	    /*
+	     * Again a duplicate test.
+	     */
+	    if (sx < 0) {
+		RE_DEBUG(!EL_CAN_DELETE, 
+			 (__F, "ERROR: cannot delete in second diff\n"),);
+		term_deletechars(el, -sx);
+	    }
+
+	    /*
+	     * write (nls-nse) chars of new starting at nse
+	     */
+	    term_overwrite(el, nse, (nls - nse));
+	}
+	else {
+	    RE_DEBUG(1,(__F, "but with nothing left to save\r\n"),);
+	    term_overwrite(el, nse, (nls - nse));
+	    RE_DEBUG(1,(__F, "cleareol %d\n", (oe - old) - (ne - new)),);
+	    term_clear_EOL(el, (oe - old) - (ne - new));
+	}
+    }
+
+    /*
+     * if we have a first insert AND WE HAVEN'T ALREADY DONE IT...
+     */
+    if ((nsb != nfd) && (osb - ofd) <= (nsb - nfd) && (fx == 0)) {
+	RE_DEBUG(1,(__F, "late first diff insert at %d...\r\n", nfd - new),);
+
+	term_move_to_char(el, nfd - new);
+	/*
+	 * Check if we have stuff to keep at the end
+	 */
+	if (nsb != ne) {
+	    RE_DEBUG(1,(__F, "with stuff to keep at end\r\n"),);
+	    /* 
+	     * We have to recalculate fx here because we set it
+	     * to zero above as a flag saying that we hadn't done
+	     * an early first insert.
+	     */
+	    fx = (nsb - nfd) - (osb - ofd);
+	    if (fx > 0) {
+		/*
+		 * insert fx chars of new starting at nfd
+		 */
+		RE_DEBUG(!EL_CAN_INSERT,
+			 (__F, "ERROR: cannot insert in late first diff\n"),);
+		term_insertwrite(el, nfd, fx);
+		re_insert(el, old, ofd - old, el->el_term.t_size.h, nfd, fx);
+	    }
+
+	    /*
+	     * write (nsb-nfd) - fx chars of new starting at (nfd + fx)
+	     */
+	    term_overwrite(el, nfd + fx, (nsb - nfd) - fx);
+	    re__strncopy(ofd + fx, nfd + fx, (nsb - nfd) - fx);
+	}
+	else {
+	    RE_DEBUG(1,(__F, "without anything to save\r\n"),);
+	    term_overwrite(el, nfd, (nsb - nfd));
+	    re__strncopy(ofd, nfd, (nsb - nfd));
+	}
+    }
+
+    /*
+     * line is now NEW up to nse
+     */
+    if (sx >= 0) {
+	RE_DEBUG(1,(__F, "second diff insert at %d...\r\n", nse - new),);
+	term_move_to_char(el, nse - new);
+	if (ols != oe) {
+	    RE_DEBUG(1,(__F, "with stuff to keep at end\r\n"),);
+	    if (sx > 0) {
+		/* insert sx chars of new starting at nse */
+		RE_DEBUG(!EL_CAN_INSERT,
+		         (__F, "ERROR: cannot insert in second diff\n"),);
+		term_insertwrite(el, nse, sx);
+	    }
+
+	    /*
+	     * write (nls-nse) - sx chars of new starting at (nse + sx)
+	     */
+	    term_overwrite(el, nse + sx, (nls - nse) - sx);
+	}
+	else {
+	    RE_DEBUG(1,(__F, "without anything to save\r\n"),);
+	    term_overwrite(el, nse, (nls - nse));
+
+	    /*
+             * No need to do a clear-to-end here because we were doing
+	     * a second insert, so we will have over written all of the
+	     * old string.
+	     */
+	}
+    }
+    RE_DEBUG(1,(__F, "done.\r\n"),);
+} /* re_update_line */
+
+
+/* re__copy_and_pad():
+ *	Copy string and pad with spaces
+ */
+private void
+re__copy_and_pad(dst, src, width)
+    char *dst, *src;
+    size_t width;
+{
+    int i;
+
+    for (i = 0; i < width; i++) {
+	if (*src == '\0')
+	    break;
+	*dst++ = *src++;
+    }
+
+    while (i < width) {
+	*dst++ = ' ';
+	i++;
+    }
+    *dst = '\0';
+} /* end re__copy_and_pad */
+
+
+/* re_refresh_cursor():
+ *	Move to the new cursor position
+ */
+protected void
+re_refresh_cursor(el)
+    EditLine *el;
+{
+    char *cp, c;
+    int h, v, th;
+
+    /* first we must find where the cursor is... */
+    h  = el->el_prompt.p_pos.h;
+    v  = el->el_prompt.p_pos.v;
+    th = el->el_term.t_size.h;		/* optimize for speed 		*/
+
+    /* do input buffer to el->el_line.cursor */
+    for (cp = el->el_line.buffer; cp < el->el_line.cursor; cp++) {	
+	c = *cp;
+	h++;			/* all chars at least this long */
+
+	if (c == '\n') {	/* handle newline in data part too */
+	    h = 0;
+	    v++;
+	}
+	else {
+	    if (c == '\t') {	/* if a tab, to next tab stop */
+		while (h & 07) {
+		    h++;
+		}
+	    }
+	    else if (iscntrl(c)) {	/* if control char */
+		h++;
+		if (h > th) {	/* if overflow, compensate */
+		    h = 1;
+		    v++;
+		}
+	    }
+	    else if (!isprint(c)) {
+		h += 3;
+		if (h > th) {	/* if overflow, compensate */
+		    h = h - th;
+		    v++;
+		}
+	    }
+	}
+
+	if (h >= th) {		/* check, extra long tabs picked up here also */
+	    h = 0;
+	    v++;
+	}
+    }
+
+    /* now go there */
+    term_move_to_line(el, v);
+    term_move_to_char(el, h);
+    term__flush();
+} /* re_refresh_cursor */
+
+
+/* re_fastputc():
+ *	Add a character fast.
+ */
+private void
+re_fastputc(el, c)
+    EditLine *el;
+    int    c;
+{
+    term__putc(c);
+    el->el_display[el->el_cursor.v][el->el_cursor.h++] = c;
+    if (el->el_cursor.h >= el->el_term.t_size.h) {	
+	/* if we must overflow */
+	el->el_cursor.h = 0;
+	el->el_cursor.v++;
+	el->el_refresh.r_oldcv++;
+	term__putc('\r');
+	term__putc('\n');
+    }
+} /* end re_fastputc */
+
+
+/* re_fastaddc():
+ *	we added just one char, handle it fast.
+ *	Assumes that screen cursor == real cursor 
+ */
+protected void
+re_fastaddc(el)
+    EditLine *el;
+{
+    char c;
+
+    c = el->el_line.cursor[-1];
+
+    if (c == '\t' || el->el_line.cursor != el->el_line.lastchar) {
+	re_refresh(el);		/* too hard to handle */
+	return;
+    }				/* else (only do at end of line, no TAB) */
+
+    if (iscntrl(c)) {		/* if control char, do caret */
+	char mc = (c == '\177') ? '?' : (c | 0100);
+	re_fastputc(el, '^');
+	re_fastputc(el, mc);
+    }
+    else if (isprint(c)) {	/* normal char */
+	re_fastputc(el, c);
+    }
+    else {
+	re_fastputc(el, '\\');
+	re_fastputc(el, ((c >> 6) & 7) + '0');
+	re_fastputc(el, ((c >> 3) & 7) + '0');
+	re_fastputc(el, (c & 7) + '0');
+    }
+    term__flush();
+} /* end re_fastaddc */
+
+
+/* re_clear_display():
+ *	clear the screen buffers so that new new prompt starts fresh. 
+ */
+protected void
+re_clear_display(el)
+    EditLine *el;
+{
+    int i;
+
+    el->el_cursor.v = 0;
+    el->el_cursor.h = 0;
+    for (i = 0; i < el->el_term.t_size.v; i++)
+	el->el_display[i][0] = '\0';
+    el->el_refresh.r_oldcv = 0;
+} /* end re_clear_display */
+
+
+/* re_clear_lines():
+ *	Make sure all lines are *really* blank 
+ */
+protected void
+re_clear_lines(el)
+    EditLine *el;
+{
+    if (EL_CAN_CEOL) {
+	int i;
+	term_move_to_char(el, 0);
+	for (i = 0; i <= el->el_refresh.r_oldcv; i++) {
+	    /* for each line on the screen */
+	    term_move_to_line(el, i);
+	    term_clear_EOL(el, el->el_term.t_size.h);
+	}
+	term_move_to_line(el, 0);
+    }
+    else {
+	term_move_to_line(el, el->el_refresh.r_oldcv);	/* go to last line */
+	term__putc('\r');				/* go to BOL */
+	term__putc('\n');				/* go to new line */
+    }
+} /* end re_clear_lines */