Update to NetBSD libedit (from Oct 1, 2003), adding some string

cleaning and history bug fixes. The code includes GNU libreadline
functionality, but the corresponding header files are not installed,
since some libreadline functions are missing. There are some minor API
changes, notably:

old: EditLine *el_init(const char *, FILE *, FILE *);
new: EditLine *el_init(const char *, FILE *, FILE *, FILE *);

old: HistEvent *history(History *h, int op, ...);
new: int history(History *h, HistEvent *ev, int op, ...); plus some
changes in operation names. See editline(3) for details.

Tested by djm@, mouring@, jmc@.

ok deraadt@

1 files changed, 487 insertions, 394 deletions

diff --git a/lib/libedit/chared.c b/lib/libedit/chared.c
index df1207f34b7..0275dfe6c81 100644
--- a/lib/libedit/chared.c
+++ b/lib/libedit/chared.c
@@ -1,5 +1,5 @@
-/*	$OpenBSD: chared.c,v 1.6 2003/06/02 20:18:40 millert Exp $	*/
-/*	$NetBSD: chared.c,v 1.2 1997/01/11 06:47:48 lukem Exp $	*/
+/*	$OpenBSD: chared.c,v 1.7 2003/10/31 08:42:24 otto Exp $	*/
+/*	$NetBSD: chared.c,v 1.19 2003/08/07 16:44:30 agc Exp $	*/
 
 /*-
  * Copyright (c) 1992, 1993
@@ -33,88 +33,106 @@
  * SUCH DAMAGE.
  */
 
+#include "config.h"
 #if !defined(lint) && !defined(SCCSID)
 #if 0
 static char sccsid[] = "@(#)chared.c	8.1 (Berkeley) 6/4/93";
 #else
-static const char rcsid[] = "$OpenBSD: chared.c,v 1.6 2003/06/02 20:18:40 millert Exp $";
+static const char rcsid[] = "$OpenBSD: chared.c,v 1.7 2003/10/31 08:42:24 otto Exp $";
 #endif
 #endif /* not lint && not SCCSID */
 
-/* 
+/*
  * chared.c: Character editor utilities
  */
-#include "sys.h"
-
 #include <stdlib.h>
 #include "el.h"
 
+/* value to leave unused in line buffer */
+#define	EL_LEAVE	2
+
 /* cv_undo():
  *	Handle state for the vi undo command
  */
 protected void
-cv_undo(el, action, size, ptr)
-    EditLine *el;
-    int action, size;
-    char *ptr;
+cv_undo(EditLine *el)
 {
-    c_undo_t *vu = &el->el_chared.c_undo;
-    vu->action = action;
-    vu->ptr    = ptr;
-    vu->isize  = size;
-    (void)memcpy(vu->buf, vu->ptr, size);
-#ifdef DEBUG_UNDO
-    (void)fprintf(el->el_errfile, "Undo buffer \"%s\" size = +%d -%d\n",
-		   vu->ptr, vu->isize, vu->dsize);
-#endif
+	c_undo_t *vu = &el->el_chared.c_undo;
+	c_redo_t *r = &el->el_chared.c_redo;
+	uint size;
+
+	/* Save entire line for undo */
+	size = el->el_line.lastchar - el->el_line.buffer;
+	vu->len = size;
+	vu->cursor = el->el_line.cursor - el->el_line.buffer;
+	memcpy(vu->buf, el->el_line.buffer, size);
+
+	/* save command info for redo */
+	r->count = el->el_state.doingarg ? el->el_state.argument : 0;
+	r->action = el->el_chared.c_vcmd.action;
+	r->pos = r->buf;
+	r->cmd = el->el_state.thiscmd;
+	r->ch = el->el_state.thisch;
+}
+
+/* cv_yank():
+ *	Save yank/delete data for paste
+ */
+protected void
+cv_yank(EditLine *el, const char *ptr, int size)
+{
+	c_kill_t *k = &el->el_chared.c_kill;
+
+	memcpy(k->buf, ptr, size +0u);
+	k->last = k->buf + size;
 }
 
 
-/* c_insert(): 
+/* c_insert():
  *	Insert num characters
  */
 protected void
-c_insert(el, num)
-    EditLine *el;
-    int num;
+c_insert(EditLine *el, int num)
 {
-    char *cp;
+	char *cp;
 
-    if (el->el_line.lastchar + num >= el->el_line.limit)
-	return;			/* can't go past end of buffer */
+	if (el->el_line.lastchar + num >= el->el_line.limit) {
+		if (!ch_enlargebufs(el, num +0u))
+			return;		/* can't go past end of buffer */
+	}
 
-    if (el->el_line.cursor < el->el_line.lastchar) {	
-	/* if I must move chars */
-	for (cp = el->el_line.lastchar; cp >= el->el_line.cursor; cp--)
-	    cp[num] = *cp;
-    }
-    el->el_line.lastchar += num;
-} /* end c_insert */
+	if (el->el_line.cursor < el->el_line.lastchar) {
+		/* if I must move chars */
+		for (cp = el->el_line.lastchar; cp >= el->el_line.cursor; cp--)
+			cp[num] = *cp;
+	}
+	el->el_line.lastchar += num;
+}
 
 
 /* c_delafter():
  *	Delete num characters after the cursor
  */
 protected void
-c_delafter(el, num)	
-    EditLine *el;
-    int num;
+c_delafter(EditLine *el, int num)
 {
 
-    if (el->el_line.cursor + num > el->el_line.lastchar)
-	num = el->el_line.lastchar - el->el_line.cursor;
+	if (el->el_line.cursor + num > el->el_line.lastchar)
+		num = el->el_line.lastchar - el->el_line.cursor;
 
-    if (num > 0) {			
-	char *cp;
+	if (el->el_map.current != el->el_map.emacs) {
+		cv_undo(el);
+		cv_yank(el, el->el_line.cursor, num);
+	}
 
-	if (el->el_map.current != el->el_map.emacs) 
-	    cv_undo(el, INSERT, num, el->el_line.cursor);
+	if (num > 0) {
+		char *cp;
 
-	for (cp = el->el_line.cursor; cp <= el->el_line.lastchar; cp++)
-	    *cp = cp[num];
+		for (cp = el->el_line.cursor; cp <= el->el_line.lastchar; cp++)
+			*cp = cp[num];
 
-	el->el_line.lastchar -= num;
-    }
+		el->el_line.lastchar -= num;
+	}
 }
 
 
@@ -122,25 +140,27 @@ c_delafter(el, num)
  *	Delete num characters before the cursor
  */
 protected void
-c_delbefore(el, num)
-    EditLine *el;
-    int num;
+c_delbefore(EditLine *el, int num)
 {
 
-    if (el->el_line.cursor - num < el->el_line.buffer)
-	num = el->el_line.cursor - el->el_line.buffer;	
+	if (el->el_line.cursor - num < el->el_line.buffer)
+		num = el->el_line.cursor - el->el_line.buffer;
 
-    if (num > 0) {		
-	char *cp;
+	if (el->el_map.current != el->el_map.emacs) {
+		cv_undo(el);
+		cv_yank(el, el->el_line.cursor - num, num);
+	}
 
-	if (el->el_map.current != el->el_map.emacs) 
-	    cv_undo(el, INSERT, num, el->el_line.cursor - num);
+	if (num > 0) {
+		char *cp;
 
-	for (cp = el->el_line.cursor - num; cp <= el->el_line.lastchar; cp++)
-	    *cp = cp[num];
+		for (cp = el->el_line.cursor - num;
+		    cp <= el->el_line.lastchar;
+		    cp++)
+			*cp = cp[num];
 
-	el->el_line.lastchar -= num;
-    }
+		el->el_line.lastchar -= num;
+	}
 }
 
 
@@ -148,10 +168,9 @@ c_delbefore(el, num)
  *	Return if p is part of a word according to emacs
  */
 protected int
-ce__isword(p) 
-    int p;
+ce__isword(int p)
 {
-    return isalpha(p) || isdigit(p) || strchr("*?_-.[]~=", p) != NULL;
+	return (isalnum(p) || strchr("*?_-.[]~=", p) != NULL);
 }
 
 
@@ -159,10 +178,23 @@ ce__isword(p)
  *	Return if p is part of a word according to vi
  */
 protected int
-cv__isword(p) 
-    int p;
+cv__isword(int p)
+{
+	if (isalnum(p) || p == '_')
+		return 1;
+	if (isgraph(p))
+		return 2;
+	return 0;
+}
+
+
+/* cv__isWord():
+ *	Return if p is part of a big word according to vi
+ */
+protected int
+cv__isWord(int p)
 {
-    return !isspace(p);
+	return (!isspace(p));
 }
 
 
@@ -170,26 +202,23 @@ cv__isword(p)
  *	Find the previous word
  */
 protected char *
-c__prev_word(p, low, n, wtest) 
-    register char *p, *low;
-    register int n;
-    int (*wtest)(int);
+c__prev_word(char *p, char *low, int n, int (*wtest)(int))
 {
-    p--;
-
-    while (n--) {
-	while ((p >= low) && !(*wtest)((unsigned char) *p)) 
-	    p--;
-	while ((p >= low) && (*wtest)((unsigned char) *p)) 
-	    p--;
-    }
-
-    /* cp now points to one character before the word */
-    p++;
-    if (p < low)
-	p = low;
-    /* cp now points where we want it */
-    return p;
+	p--;
+
+	while (n--) {
+		while ((p >= low) && !(*wtest)((unsigned char) *p))
+			p--;
+		while ((p >= low) && (*wtest)((unsigned char) *p))
+			p--;
+	}
+
+	/* cp now points to one character before the word */
+	p++;
+	if (p < low)
+		p = low;
+	/* cp now points where we want it */
+	return (p);
 }
 
 
@@ -197,53 +226,46 @@ c__prev_word(p, low, n, wtest)
  *	Find the next word
  */
 protected char *
-c__next_word(p, high, n, wtest)
-    register char *p, *high;
-    register int n;
-    int (*wtest)(int);
+c__next_word(char *p, char *high, int n, int (*wtest)(int))
 {
-    while (n--) {
-	while ((p < high) && !(*wtest)((unsigned char) *p)) 
-	    p++;
-	while ((p < high) && (*wtest)((unsigned char) *p)) 
-	    p++;
-    }
-    if (p > high)
-	p = high;
-    /* p now points where we want it */
-    return p;
+	while (n--) {
+		while ((p < high) && !(*wtest)((unsigned char) *p))
+			p++;
+		while ((p < high) && (*wtest)((unsigned char) *p))
+			p++;
+	}
+	if (p > high)
+		p = high;
+	/* p now points where we want it */
+	return (p);
 }
 
 /* cv_next_word():
  *	Find the next word vi style
  */
 protected char *
-cv_next_word(el, p, high, n, wtest)
-    EditLine *el;
-    register char *p, *high;
-    register int n;
-    int (*wtest)(int);
+cv_next_word(EditLine *el, char *p, char *high, int n, int (*wtest)(int))
 {
-    int test;
+	int test;
+
+	while (n--) {
+		test = (*wtest)((unsigned char) *p);
+		while ((p < high) && (*wtest)((unsigned char) *p) == test)
+			p++;
+		/*
+		 * vi historically deletes with cw only the word preserving the
+		 * trailing whitespace! This is not what 'w' does..
+		 */
+		if (n || el->el_chared.c_vcmd.action != (DELETE|INSERT))
+			while ((p < high) && isspace((unsigned char) *p))
+				p++;
+	}
 
-    while (n--) {
-    	test = (*wtest)((unsigned char) *p);
-	while ((p < high) && (*wtest)((unsigned char) *p) == test) 
-	    p++;
-	/*
-	 * vi historically deletes with cw only the word preserving the
-	 * trailing whitespace! This is not what 'w' does..
-	 */
-	if (el->el_chared.c_vcmd.action != (DELETE|INSERT)) 
-	    while ((p < high) && isspace((unsigned char) *p)) 
-		p++;
-    }
-
-    /* p now points where we want it */
-    if (p > high)
-	return high;
-    else
-	return p;
+	/* p now points where we want it */
+	if (p > high)
+		return (high);
+	else
+		return (p);
 }
 
 
@@ -251,36 +273,25 @@ cv_next_word(el, p, high, n, wtest)
  *	Find the previous word vi style
  */
 protected char *
-cv_prev_word(el, p, low, n, wtest)
-    EditLine *el;
-    register char *p, *low;
-    register int n;
-    int (*wtest)(int);
+cv_prev_word(char *p, char *low, int n, int (*wtest)(int))
 {
-    int test;
+	int test;
 
-    while (n--) {
 	p--;
-	/*
-	 * vi historically deletes with cb only the word preserving the
-	 * leading whitespace! This is not what 'b' does..
-	 */
-	if (el->el_chared.c_vcmd.action != (DELETE|INSERT)) 
-	    while ((p > low) && isspace((unsigned char) *p)) 
-		p--;
-	test = (*wtest)((unsigned char) *p);
-	while ((p >= low) && (*wtest)((unsigned char) *p) == test) 
-	    p--;
+	while (n--) {
+		while ((p > low) && isspace((unsigned char) *p))
+			p--;
+		test = (*wtest)((unsigned char) *p);
+		while ((p >= low) && (*wtest)((unsigned char) *p) == test)
+			p--;
+	}
 	p++;
-	while (isspace((unsigned char) *p)) 
-		p++;
-    }
-
-    /* p now points where we want it */
-    if (p < low)
-	return low;
-    else
-	return p;
+
+	/* p now points where we want it */
+	if (p < low)
+		return (low);
+	else
+		return (p);
 }
 
 
@@ -291,30 +302,30 @@ cv_prev_word(el, p, low, n, wtest)
  * 	Return p pointing to last char used.
  */
 protected char *
-c__number(p, num, dval)
-    char *p;	/* character position */
-    int *num;	/* Return value	*/
-    int dval;	/* dval is the number to subtract from like $-3 */
+c__number(
+    char *p,	/* character position */
+    int *num,	/* Return value	*/
+    int dval)	/* dval is the number to subtract from like $-3 */
 {
-    register int i;
-    register int sign = 1;
-
-    if (*++p == '^') {
-	*num = 1;
-	return p;
-    }
-    if (*p == '$') {
-	if (*++p != '-') {
-	    *num = 0x7fffffff;	/* Handle $ */
-	    return --p;
+	int i;
+	int sign = 1;
+
+	if (*++p == '^') {
+		*num = 1;
+		return (p);
+	}
+	if (*p == '$') {
+		if (*++p != '-') {
+			*num = 0x7fffffff;	/* Handle $ */
+			return (--p);
+		}
+		sign = -1;			/* Handle $- */
+		++p;
 	}
-	sign = -1;		/* Handle $- */
-	++p;
-    }
-    for (i = 0; isdigit((unsigned char) *p); i = 10 * i + *p++ - '0')
-	continue;
-    *num = (sign < 0 ? dval - i : i);
-    return --p;
+	for (i = 0; isdigit((unsigned char) *p); i = 10 * i + *p++ - '0')
+		continue;
+	*num = (sign < 0 ? dval - i : i);
+	return (--p);
 }
 #endif
 
@@ -322,53 +333,37 @@ c__number(p, num, dval)
  *	Finish vi delete action
  */
 protected void
-cv_delfini(el)		
-    EditLine *el;
+cv_delfini(EditLine *el)
 {
-    register int size;
-    int oaction;
-
-    if (el->el_chared.c_vcmd.action & INSERT)
-	el->el_map.current = el->el_map.key;
+	int size;
+	int action = el->el_chared.c_vcmd.action;
 
-    oaction = el->el_chared.c_vcmd.action;
-    el->el_chared.c_vcmd.action = NOP;
+	if (action & INSERT)
+		el->el_map.current = el->el_map.key;
 
-    if (el->el_chared.c_vcmd.pos == 0) 
-	return;
+	if (el->el_chared.c_vcmd.pos == 0)
+		/* sanity */
+		return;
 
-
-    if (el->el_line.cursor > el->el_chared.c_vcmd.pos) {
-	size = (int) (el->el_line.cursor - el->el_chared.c_vcmd.pos);
-	c_delbefore(el, size); 
+	size = el->el_line.cursor - el->el_chared.c_vcmd.pos;
+	if (size == 0)
+		size = 1;
 	el->el_line.cursor = el->el_chared.c_vcmd.pos;
-	re_refresh_cursor(el);
-    }
-    else if (el->el_line.cursor < el->el_chared.c_vcmd.pos) {
-	size = (int)(el->el_chared.c_vcmd.pos - el->el_line.cursor);
-	c_delafter(el, size);
-    }
-    else {
-	size = 1;
-	c_delafter(el, size);
-    }
-    switch (oaction) {
-    case DELETE|INSERT:
-	el->el_chared.c_undo.action = DELETE|INSERT;
-	break;
-    case DELETE:
-	el->el_chared.c_undo.action = INSERT;
-	break;
-    case NOP:
-    case INSERT:
-    default:
-	abort();
-	break;
-    }
-	
-
-    el->el_chared.c_undo.ptr = el->el_line.cursor;
-    el->el_chared.c_undo.dsize = size;
+	if (action & YANK) {
+		if (size > 0)
+			cv_yank(el, el->el_line.cursor, size);
+		else
+			cv_yank(el, el->el_line.cursor + size, -size);
+	} else {
+		if (size > 0) {
+			c_delafter(el, size);
+			re_refresh_cursor(el);
+		} else  {
+			c_delbefore(el, -size);
+			el->el_line.cursor += size;
+		}
+	}
+	el->el_chared.c_vcmd.action = NOP;
 }
 
 
@@ -377,21 +372,19 @@ cv_delfini(el)
  *	Go to the end of this word according to emacs
  */
 protected char *
-ce__endword(p, high, n)
-    char *p, *high;
-    int n;
+ce__endword(char *p, char *high, int n)
 {
-    p++;
+	p++;
 
-    while (n--) {
-	while ((p < high) && isspace((unsigned char) *p))
-	    p++;
-	while ((p < high) && !isspace((unsigned char) *p)) 
-	    p++;
-    }
+	while (n--) {
+		while ((p < high) && isspace((unsigned char) *p))
+			p++;
+		while ((p < high) && !isspace((unsigned char) *p))
+			p++;
+	}
 
-    p--;
-    return p;
+	p--;
+	return (p);
 }
 #endif
 
@@ -400,124 +393,217 @@ ce__endword(p, high, n)
  *	Go to the end of this word according to vi
  */
 protected char *
-cv__endword(p, high, n)
-    char *p, *high;
-    int n;
+cv__endword(char *p, char *high, int n, int (*wtest)(int))
 {
-    p++;
+	int test;
+
+	p++;
 
-    while (n--) {
-	while ((p < high) && isspace((unsigned char) *p)) 
-	    p++;
+	while (n--) {
+		while ((p < high) && isspace((unsigned char) *p))
+			p++;
 
-	if (isalnum((unsigned char) *p))
-	    while ((p < high) && isalnum((unsigned char) *p)) 
-		p++;
-	else
-	    while ((p < high) && !(isspace((unsigned char) *p) || 
-				   isalnum((unsigned char) *p)))
-		p++;
-    }
-    p--;
-    return p;
+		test = (*wtest)((unsigned char) *p);
+		while ((p < high) && (*wtest)((unsigned char) *p) == test)
+			p++;
+	}
+	p--;
+	return (p);
 }
 
 /* ch_init():
  *	Initialize the character editor
  */
 protected int
-ch_init(el)
-    EditLine *el;
+ch_init(EditLine *el)
 {
-    el->el_line.buffer              = (char *)  el_malloc(EL_BUFSIZ);
-    (void)memset(el->el_line.buffer, 0, EL_BUFSIZ);
-    el->el_line.cursor              = el->el_line.buffer;
-    el->el_line.lastchar            = el->el_line.buffer;
-    el->el_line.limit  		    = &el->el_line.buffer[EL_BUFSIZ - 2];
-
-    el->el_chared.c_undo.buf        = (char *)  el_malloc(EL_BUFSIZ);
-    (void)memset(el->el_chared.c_undo.buf, 0, EL_BUFSIZ);
-    el->el_chared.c_undo.action     = NOP;
-    el->el_chared.c_undo.isize      = 0;
-    el->el_chared.c_undo.dsize      = 0;
-    el->el_chared.c_undo.ptr        = el->el_line.buffer;
-
-    el->el_chared.c_vcmd.action     = NOP;
-    el->el_chared.c_vcmd.pos        = el->el_line.buffer;
-    el->el_chared.c_vcmd.ins        = el->el_line.buffer;
-
-    el->el_chared.c_kill.buf        = (char *)  el_malloc(EL_BUFSIZ);
-    (void)memset(el->el_chared.c_kill.buf, 0, EL_BUFSIZ);
-    el->el_chared.c_kill.mark       = el->el_line.buffer;
-    el->el_chared.c_kill.last       = el->el_chared.c_kill.buf;
-
-    el->el_map.current              = el->el_map.key;
-
-    el->el_state.inputmode = MODE_INSERT; /* XXX: save a default */
-    el->el_state.doingarg  = 0;
-    el->el_state.metanext  = 0;
-    el->el_state.argument  = 1;
-    el->el_state.lastcmd   = ED_UNASSIGNED;
-
-    el->el_chared.c_macro.nline     = NULL;
-    el->el_chared.c_macro.level     = -1;
-    el->el_chared.c_macro.macro     = (char **) el_malloc(EL_MAXMACRO * 
-						          sizeof(char *));
-    return 0;
+	el->el_line.buffer		= (char *) el_malloc(EL_BUFSIZ);
+	if (el->el_line.buffer == NULL)
+		return (-1);
+
+	(void) memset(el->el_line.buffer, 0, EL_BUFSIZ);
+	el->el_line.cursor		= el->el_line.buffer;
+	el->el_line.lastchar		= el->el_line.buffer;
+	el->el_line.limit		= &el->el_line.buffer[EL_BUFSIZ - EL_LEAVE];
+
+	el->el_chared.c_undo.buf	= (char *) el_malloc(EL_BUFSIZ);
+	if (el->el_chared.c_undo.buf == NULL)
+		return (-1);
+	(void) memset(el->el_chared.c_undo.buf, 0, EL_BUFSIZ);
+	el->el_chared.c_undo.len	= -1;
+	el->el_chared.c_undo.cursor	= 0;
+	el->el_chared.c_redo.buf	= (char *) el_malloc(EL_BUFSIZ);
+	if (el->el_chared.c_redo.buf == NULL)
+		return (-1);
+	el->el_chared.c_redo.pos	= el->el_chared.c_redo.buf;
+	el->el_chared.c_redo.lim	= el->el_chared.c_redo.buf + EL_BUFSIZ;
+	el->el_chared.c_redo.cmd	= ED_UNASSIGNED;
+
+	el->el_chared.c_vcmd.action	= NOP;
+	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
+
+	el->el_chared.c_kill.buf	= (char *) el_malloc(EL_BUFSIZ);
+	if (el->el_chared.c_kill.buf == NULL)
+		return (-1);
+	(void) memset(el->el_chared.c_kill.buf, 0, EL_BUFSIZ);
+	el->el_chared.c_kill.mark	= el->el_line.buffer;
+	el->el_chared.c_kill.last	= el->el_chared.c_kill.buf;
+
+	el->el_map.current		= el->el_map.key;
+
+	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
+	el->el_state.doingarg		= 0;
+	el->el_state.metanext		= 0;
+	el->el_state.argument		= 1;
+	el->el_state.lastcmd		= ED_UNASSIGNED;
+
+	el->el_chared.c_macro.nline	= NULL;
+	el->el_chared.c_macro.level	= -1;
+	el->el_chared.c_macro.macro	= (char **) el_malloc(EL_MAXMACRO *
+	    sizeof(char *));
+	if (el->el_chared.c_macro.macro == NULL)
+		return (-1);
+	return (0);
 }
 
 /* ch_reset():
  *	Reset the character editor
  */
 protected void
-ch_reset(el)
-    EditLine *el;
+ch_reset(EditLine *el)
 {
-    el->el_line.cursor              = el->el_line.buffer;
-    el->el_line.lastchar            = el->el_line.buffer;
+	el->el_line.cursor		= el->el_line.buffer;
+	el->el_line.lastchar		= el->el_line.buffer;
 
-    el->el_chared.c_undo.action     = NOP;
-    el->el_chared.c_undo.isize      = 0;
-    el->el_chared.c_undo.dsize      = 0;
-    el->el_chared.c_undo.ptr        = el->el_line.buffer;
+	el->el_chared.c_undo.len	= -1;
+	el->el_chared.c_undo.cursor	= 0;
 
-    el->el_chared.c_vcmd.action     = NOP;
-    el->el_chared.c_vcmd.pos        = el->el_line.buffer;
-    el->el_chared.c_vcmd.ins        = el->el_line.buffer;
+	el->el_chared.c_vcmd.action	= NOP;
+	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
 
-    el->el_chared.c_kill.mark       = el->el_line.buffer;
+	el->el_chared.c_kill.mark	= el->el_line.buffer;
 
-    el->el_map.current              = el->el_map.key;
+	el->el_map.current		= el->el_map.key;
 
-    el->el_state.inputmode = MODE_INSERT; /* XXX: save a default */
-    el->el_state.doingarg  = 0;
-    el->el_state.metanext  = 0;
-    el->el_state.argument  = 1;
-    el->el_state.lastcmd   = ED_UNASSIGNED;
+	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
+	el->el_state.doingarg		= 0;
+	el->el_state.metanext		= 0;
+	el->el_state.argument		= 1;
+	el->el_state.lastcmd		= ED_UNASSIGNED;
 
-    el->el_chared.c_macro.level     = -1;
+	el->el_chared.c_macro.level	= -1;
 
-    el->el_history.eventno = 0;
+	el->el_history.eventno		= 0;
 }
 
+/* ch_enlargebufs():
+ *	Enlarge line buffer to be able to hold twice as much characters.
+ *	Returns 1 if successful, 0 if not.
+ */
+protected int
+ch_enlargebufs(el, addlen)
+	EditLine *el;
+	size_t addlen;
+{
+	size_t sz, newsz;
+	char *newbuffer, *oldbuf, *oldkbuf;
+
+	sz = el->el_line.limit - el->el_line.buffer + EL_LEAVE;
+	newsz = sz * 2;
+	/*
+	 * If newly required length is longer than current buffer, we need
+	 * to make the buffer big enough to hold both old and new stuff.
+	 */
+	if (addlen > sz) {
+		while(newsz - sz < addlen)
+			newsz *= 2;
+	}
+
+	/*
+	 * Reallocate line buffer.
+	 */
+	newbuffer = el_realloc(el->el_line.buffer, newsz);
+	if (!newbuffer)
+		return 0;
+
+	/* zero the newly added memory, leave old data in */
+	(void) memset(&newbuffer[sz], 0, newsz - sz);
+	    
+	oldbuf = el->el_line.buffer;
+
+	el->el_line.buffer = newbuffer;
+	el->el_line.cursor = newbuffer + (el->el_line.cursor - oldbuf);
+	el->el_line.lastchar = newbuffer + (el->el_line.lastchar - oldbuf);
+	/* don't set new size until all buffers are enlarged */
+	el->el_line.limit  = &newbuffer[sz - EL_LEAVE];
+
+	/*
+	 * Reallocate kill buffer.
+	 */
+	newbuffer = el_realloc(el->el_chared.c_kill.buf, newsz);
+	if (!newbuffer)
+		return 0;
+
+	/* zero the newly added memory, leave old data in */
+	(void) memset(&newbuffer[sz], 0, newsz - sz);
+
+	oldkbuf = el->el_chared.c_kill.buf;
+
+	el->el_chared.c_kill.buf = newbuffer;
+	el->el_chared.c_kill.last = newbuffer +
+					(el->el_chared.c_kill.last - oldkbuf);
+	el->el_chared.c_kill.mark = el->el_line.buffer +
+					(el->el_chared.c_kill.mark - oldbuf);
+
+	/*
+	 * Reallocate undo buffer.
+	 */
+	newbuffer = el_realloc(el->el_chared.c_undo.buf, newsz);
+	if (!newbuffer)
+		return 0;
+
+	/* zero the newly added memory, leave old data in */
+	(void) memset(&newbuffer[sz], 0, newsz - sz);
+	el->el_chared.c_undo.buf = newbuffer;
+
+	newbuffer = el_realloc(el->el_chared.c_redo.buf, newsz);
+	if (!newbuffer)
+		return 0;
+	el->el_chared.c_redo.pos = newbuffer +
+			(el->el_chared.c_redo.pos - el->el_chared.c_redo.buf);
+	el->el_chared.c_redo.lim = newbuffer +
+			(el->el_chared.c_redo.lim - el->el_chared.c_redo.buf);
+	el->el_chared.c_redo.buf = newbuffer;
+	
+	if (!hist_enlargebuf(el, sz, newsz))
+		return 0;
+
+	/* Safe to set enlarged buffer size */
+	el->el_line.limit  = &newbuffer[newsz - EL_LEAVE];
+	return 1;
+}
 
 /* ch_end():
  *	Free the data structures used by the editor
  */
 protected void
-ch_end(el)
-    EditLine *el;
+ch_end(EditLine *el)
 {
-    el_free((ptr_t) el->el_line.buffer);
-    el->el_line.buffer = NULL;
-    el->el_line.limit = NULL;
-    el_free((ptr_t) el->el_chared.c_undo.buf);
-    el->el_chared.c_undo.buf = NULL;
-    el_free((ptr_t) el->el_chared.c_kill.buf);
-    el->el_chared.c_kill.buf = NULL;
-    el_free((ptr_t) el->el_chared.c_macro.macro);
-    el->el_chared.c_macro.macro = NULL;
-    ch_reset(el);
+	el_free((ptr_t) el->el_line.buffer);
+	el->el_line.buffer = NULL;
+	el->el_line.limit = NULL;
+	el_free((ptr_t) el->el_chared.c_undo.buf);
+	el->el_chared.c_undo.buf = NULL;
+	el_free((ptr_t) el->el_chared.c_redo.buf);
+	el->el_chared.c_redo.buf = NULL;
+	el->el_chared.c_redo.pos = NULL;
+	el->el_chared.c_redo.lim = NULL;
+	el->el_chared.c_redo.cmd = ED_UNASSIGNED;
+	el_free((ptr_t) el->el_chared.c_kill.buf);
+	el->el_chared.c_kill.buf = NULL;
+	el_free((ptr_t) el->el_chared.c_macro.macro);
+	el->el_chared.c_macro.macro = NULL;
+	ch_reset(el);
 }
 
 
@@ -525,21 +611,21 @@ ch_end(el)
  *	Insert string at cursorI
  */
 public int
-el_insertstr(el, s)
-    EditLine *el;
-    char   *s;
+el_insertstr(EditLine *el, const char *s)
 {
-    int len;
+	size_t len;
 
-    if ((len = strlen(s)) == 0)
-	return -1;
-    if (el->el_line.lastchar + len >= el->el_line.limit)
-	return -1;
+	if ((len = strlen(s)) == 0)
+		return (-1);
+	if (el->el_line.lastchar + len >= el->el_line.limit) {
+		if (!ch_enlargebufs(el, len))
+			return (-1);
+	}
 
-    c_insert(el, len);
-    while (*s)
-	*el->el_line.cursor++ = *s++;
-    return 0;
+	c_insert(el, (int)len);
+	while (*s)
+		*el->el_line.cursor++ = *s++;
+	return (0);
 }
 
 
@@ -547,74 +633,82 @@ el_insertstr(el, s)
  *	Delete num characters before the cursor
  */
 public void
-el_deletestr(el, n)
-    EditLine *el;
-    int     n;
+el_deletestr(EditLine *el, int n)
 {
-    if (n <= 0)
-	return;
+	if (n <= 0)
+		return;
 
-    if (el->el_line.cursor < &el->el_line.buffer[n]) 
-	return;
+	if (el->el_line.cursor < &el->el_line.buffer[n])
+		return;
 
-    c_delbefore(el, n);		/* delete before dot */
-    el->el_line.cursor -= n;
-    if (el->el_line.cursor < el->el_line.buffer)
-	el->el_line.cursor = el->el_line.buffer;
+	c_delbefore(el, n);		/* delete before dot */
+	el->el_line.cursor -= n;
+	if (el->el_line.cursor < el->el_line.buffer)
+		el->el_line.cursor = el->el_line.buffer;
 }
 
 /* c_gets():
  *	Get a string
  */
 protected int
-c_gets(el, buf)
-    EditLine *el;
-    char *buf;
+c_gets(EditLine *el, char *buf, const char *prompt)
 {
-    char ch;
-    int len = 0;
-
-    for (ch = 0; ch == 0;) {
-	if (el_getc(el, &ch) != 1)
-	    return ed_end_of_file(el, 0);
-	switch (ch) {
-	case 0010:	/* Delete and backspace */
-	case 0177:
-	    if (len > 1) {
-		*el->el_line.cursor-- = '\0';
-		el->el_line.lastchar = el->el_line.cursor;
-		buf[len--] = '\0';
-	    }
-	    else {
-		el->el_line.buffer[0] = '\0';
-		el->el_line.lastchar = el->el_line.buffer;
-		el->el_line.cursor = el->el_line.buffer;
-		return CC_REFRESH;
-	    }
-	    re_refresh(el);
-	    ch = 0;
-	    break;
-
-	case 0033:	/* ESC */
-	case '\r':	/* Newline */
-	case '\n':
-	    break;
-
-	default:
-	    if (len >= EL_BUFSIZ)
-		term_beep(el);
-	    else {
-		buf[len++] = ch;
-		*el->el_line.cursor++ = ch;
-		el->el_line.lastchar = el->el_line.cursor;
-	    }
-	    re_refresh(el);
-	    ch = 0;
-	    break;
+	char ch;
+	int len;
+	char *cp = el->el_line.buffer;
+
+	if (prompt) {
+		len = strlen(prompt);
+		memcpy(cp, prompt, len + 0u);
+		cp += len;
+	}
+	len = 0;
+
+	for (;;) {
+		el->el_line.cursor = cp;
+		*cp = ' ';
+		el->el_line.lastchar = cp + 1;
+		re_refresh(el);
+
+		if (el_getc(el, &ch) != 1) {
+			ed_end_of_file(el, 0);
+			len = -1;
+			break;
+		}
+
+		switch (ch) {
+
+		case 0010:	/* Delete and backspace */
+		case 0177:
+			if (len <= 0) {
+				len = -1;
+				break;
+			}
+			cp--;
+			continue;
+
+		case 0033:	/* ESC */
+		case '\r':	/* Newline */
+		case '\n':
+			buf[len] = ch;
+			break;
+
+		default:
+			if (len >= EL_BUFSIZ - 16)
+				term_beep(el);
+			else {
+				buf[len++] = ch;
+				*cp++ = ch;
+			}
+			continue;
+		}
+		break;
 	}
-    }
-    buf[len] = ch;
-    return len;
+
+	el->el_line.buffer[0] = '\0';
+	el->el_line.lastchar = el->el_line.buffer;
+	el->el_line.cursor = el->el_line.buffer;
+	return len;
 }
 
 
@@ -622,21 +716,20 @@ c_gets(el, buf)
  *	Return the current horizontal position of the cursor
  */
 protected int
-c_hpos(el)
-    EditLine *el;
+c_hpos(EditLine *el)
 {
-    char *ptr;
+	char *ptr;
 
-    /*
-     * Find how many characters till the beginning of this line.
-     */
-    if (el->el_line.cursor == el->el_line.buffer)
-	return 0;
-    else {
-	for (ptr = el->el_line.cursor - 1; 
-	     ptr >= el->el_line.buffer && *ptr != '\n';
-	     ptr--)
-	    continue;
-	return el->el_line.cursor - ptr - 1;
-    }
+	/*
+	 * Find how many characters till the beginning of this line.
+	 */
+	if (el->el_line.cursor == el->el_line.buffer)
+		return (0);
+	else {
+		for (ptr = el->el_line.cursor - 1;
+		     ptr >= el->el_line.buffer && *ptr != '\n';
+		     ptr--)
+			continue;
+		return (el->el_line.cursor - ptr - 1);
+	}
 }