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      1 /*	$NetBSD: chared.c,v 1.65 2025/12/14 18:07:40 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1992, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Christos Zoulas of Cornell University.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. Neither the name of the University nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 #include "config.h"
     36 #if !defined(lint) && !defined(SCCSID)
     37 #if 0
     38 static char sccsid[] = "@(#)chared.c	8.1 (Berkeley) 6/4/93";
     39 #else
     40 __RCSID("$NetBSD: chared.c,v 1.65 2025/12/14 18:07:40 christos Exp $");
     41 #endif
     42 #endif /* not lint && not SCCSID */
     43 
     44 /*
     45  * chared.c: Character editor utilities
     46  */
     47 #include <ctype.h>
     48 #include <stdlib.h>
     49 #include <string.h>
     50 
     51 #include "el.h"
     52 #include "common.h"
     53 #include "fcns.h"
     54 
     55 /* value to leave unused in line buffer */
     56 #define	EL_LEAVE	2
     57 
     58 /* cv_undo():
     59  *	Handle state for the vi undo command
     60  */
     61 libedit_private void
     62 cv_undo(EditLine *el)
     63 {
     64 	c_undo_t *vu = &el->el_chared.c_undo;
     65 	c_redo_t *r = &el->el_chared.c_redo;
     66 	size_t size;
     67 
     68 	/* Save entire line for undo */
     69 	size = (size_t)(el->el_line.lastchar - el->el_line.buffer);
     70 	vu->len = (ssize_t)size;
     71 	vu->cursor = (int)(el->el_line.cursor - el->el_line.buffer);
     72 	(void)memcpy(vu->buf, el->el_line.buffer, size * sizeof(*vu->buf));
     73 
     74 	/* save command info for redo */
     75 	r->count = el->el_state.doingarg ? el->el_state.argument : 0;
     76 	r->action = el->el_chared.c_vcmd.action;
     77 	r->pos = r->buf;
     78 	r->cmd = el->el_state.thiscmd;
     79 	r->ch = el->el_state.thisch;
     80 }
     81 
     82 /* cv_yank():
     83  *	Save yank/delete data for paste
     84  */
     85 libedit_private void
     86 cv_yank(EditLine *el, const wchar_t *ptr, int size)
     87 {
     88 	c_kill_t *k = &el->el_chared.c_kill;
     89 
     90 	(void)memcpy(k->buf, ptr, (size_t)size * sizeof(*k->buf));
     91 	k->last = k->buf + size;
     92 }
     93 
     94 
     95 /* c_insert():
     96  *	Insert num characters
     97  */
     98 libedit_private void
     99 c_insert(EditLine *el, int num)
    100 {
    101 	wchar_t *cp;
    102 
    103 	if (el->el_line.lastchar + num >= el->el_line.limit) {
    104 		if (!ch_enlargebufs(el, (size_t)num))
    105 			return;		/* can't go past end of buffer */
    106 	}
    107 
    108 	if (el->el_line.cursor < el->el_line.lastchar) {
    109 		/* if I must move chars */
    110 		for (cp = el->el_line.lastchar; cp >= el->el_line.cursor; cp--)
    111 			cp[num] = *cp;
    112 	}
    113 	el->el_line.lastchar += num;
    114 }
    115 
    116 
    117 /* c_delafter():
    118  *	Delete num characters after the cursor
    119  */
    120 libedit_private void
    121 c_delafter(EditLine *el, int num)
    122 {
    123 
    124 	if (el->el_line.cursor + num > el->el_line.lastchar)
    125 		num = (int)(el->el_line.lastchar - el->el_line.cursor);
    126 
    127 	if (el->el_map.current != el->el_map.emacs) {
    128 		cv_undo(el);
    129 		cv_yank(el, el->el_line.cursor, num);
    130 	}
    131 
    132 	if (num > 0) {
    133 		wchar_t *cp;
    134 
    135 		for (cp = el->el_line.cursor; cp <= el->el_line.lastchar; cp++)
    136 			*cp = cp[num];
    137 
    138 		el->el_line.lastchar -= num;
    139 	}
    140 }
    141 
    142 
    143 /* c_delafter1():
    144  *	Delete the character after the cursor, do not yank
    145  */
    146 libedit_private void
    147 c_delafter1(EditLine *el)
    148 {
    149 	wchar_t *cp;
    150 
    151 	for (cp = el->el_line.cursor; cp <= el->el_line.lastchar; cp++)
    152 		*cp = cp[1];
    153 
    154 	el->el_line.lastchar--;
    155 }
    156 
    157 
    158 /* c_delbefore():
    159  *	Delete num characters before the cursor
    160  */
    161 libedit_private void
    162 c_delbefore(EditLine *el, int num)
    163 {
    164 
    165 	if (el->el_line.cursor - num < el->el_line.buffer)
    166 		num = (int)(el->el_line.cursor - el->el_line.buffer);
    167 
    168 	if (el->el_map.current != el->el_map.emacs) {
    169 		cv_undo(el);
    170 		cv_yank(el, el->el_line.cursor - num, num);
    171 	}
    172 
    173 	if (num > 0) {
    174 		wchar_t *cp;
    175 
    176 		for (cp = el->el_line.cursor - num;
    177 		    &cp[num] <= el->el_line.lastchar;
    178 		    cp++)
    179 			*cp = cp[num];
    180 
    181 		el->el_line.lastchar -= num;
    182 	}
    183 }
    184 
    185 
    186 /* c_delbefore1():
    187  *	Delete the character before the cursor, do not yank
    188  */
    189 libedit_private void
    190 c_delbefore1(EditLine *el)
    191 {
    192 	wchar_t *cp;
    193 
    194 	for (cp = el->el_line.cursor - 1; cp <= el->el_line.lastchar; cp++)
    195 		*cp = cp[1];
    196 
    197 	el->el_line.lastchar--;
    198 }
    199 
    200 
    201 /* ce__isword():
    202  *	Return if p is part of a word according to emacs
    203  */
    204 libedit_private int
    205 ce__isword(EditLine *el, wint_t p)
    206 {
    207 	return iswalnum(p) || wcschr(el->el_map.wordchars, p) != NULL;
    208 }
    209 
    210 
    211 /* cv__isword():
    212  *	Return if p is part of a word according to vi
    213  */
    214 libedit_private int
    215 cv__isword(EditLine *el, wint_t p)
    216 {
    217 	if (iswalnum(p) || wcschr(el->el_map.wordchars, p) != NULL)
    218 		return 1;
    219 	if (iswgraph(p))
    220 		return 2;
    221 	return 0;
    222 }
    223 
    224 
    225 /* cv__isWord():
    226  *	Return if p is part of a big word according to vi
    227  */
    228 libedit_private int
    229 cv__isWord(EditLine *el __attribute__((__unused__)), wint_t p)
    230 {
    231 	return !iswspace(p);
    232 }
    233 
    234 
    235 /* c__prev_word():
    236  *	Find the previous word
    237  */
    238 libedit_private wchar_t *
    239 c__prev_word(EditLine *el, wchar_t *p, wchar_t *low, int n,
    240     int (*wtest)(EditLine *, wint_t))
    241 {
    242 	p--;
    243 
    244 	while (n--) {
    245 		while ((p >= low) && !(*wtest)(el, *p))
    246 			p--;
    247 		while ((p >= low) && (*wtest)(el, *p))
    248 			p--;
    249 	}
    250 
    251 	/* cp now points to one character before the word */
    252 	p++;
    253 	if (p < low)
    254 		p = low;
    255 	/* cp now points where we want it */
    256 	return p;
    257 }
    258 
    259 
    260 /* c__next_word():
    261  *	Find the next word
    262  */
    263 libedit_private wchar_t *
    264 c__next_word(EditLine *el, wchar_t *p, wchar_t *high, int n,
    265     int (*wtest)(EditLine *, wint_t))
    266 {
    267 	while (n--) {
    268 		while ((p < high) && !(*wtest)(el, *p))
    269 			p++;
    270 		while ((p < high) && (*wtest)(el, *p))
    271 			p++;
    272 	}
    273 	if (p > high)
    274 		p = high;
    275 	/* p now points where we want it */
    276 	return p;
    277 }
    278 
    279 /* cv_next_word():
    280  *	Find the next word vi style
    281  */
    282 libedit_private wchar_t *
    283 cv_next_word(EditLine *el, wchar_t *p, wchar_t *high, int n,
    284     int (*wtest)(EditLine *el, wint_t))
    285 {
    286 	int test;
    287 
    288 	while (n--) {
    289 		test = (*wtest)(el, *p);
    290 		while ((p < high) && (*wtest)(el, *p) == test)
    291 			p++;
    292 		/*
    293 		 * vi historically deletes with cw only the word preserving the
    294 		 * trailing whitespace! This is not what 'w' does..
    295 		 */
    296 		if (n || el->el_chared.c_vcmd.action != (DELETE|INSERT))
    297 			while ((p < high) && iswspace(*p))
    298 				p++;
    299 	}
    300 
    301 	/* p now points where we want it */
    302 	if (p > high)
    303 		return high;
    304 	else
    305 		return p;
    306 }
    307 
    308 
    309 /* cv_prev_word():
    310  *	Find the previous word vi style
    311  */
    312 libedit_private wchar_t *
    313 cv_prev_word(EditLine *el, wchar_t *p, wchar_t *low, int n,
    314     int (*wtest)(EditLine *el, wint_t))
    315 {
    316 	int test;
    317 
    318 	p--;
    319 	while (n--) {
    320 		while ((p > low) && iswspace(*p))
    321 			p--;
    322 		test = (*wtest)(el, *p);
    323 		while ((p >= low) && (*wtest)(el, *p) == test)
    324 			p--;
    325 		if (p < low)
    326 			return low;
    327 	}
    328 	p++;
    329 
    330 	/* p now points where we want it */
    331 	if (p < low)
    332 		return low;
    333 	else
    334 		return p;
    335 }
    336 
    337 
    338 /* cv_delfini():
    339  *	Finish vi delete action
    340  */
    341 libedit_private void
    342 cv_delfini(EditLine *el)
    343 {
    344 	int size;
    345 	int action = el->el_chared.c_vcmd.action;
    346 
    347 	if (action & INSERT)
    348 		el->el_map.current = el->el_map.key;
    349 
    350 	if (el->el_chared.c_vcmd.pos == 0)
    351 		/* sanity */
    352 		return;
    353 
    354 	size = (int)(el->el_line.cursor - el->el_chared.c_vcmd.pos);
    355 	if (size == 0)
    356 		size = 1;
    357 	el->el_line.cursor = el->el_chared.c_vcmd.pos;
    358 	if (action & YANK) {
    359 		if (size > 0)
    360 			cv_yank(el, el->el_line.cursor, size);
    361 		else
    362 			cv_yank(el, el->el_line.cursor + size, -size);
    363 	} else {
    364 		if (size > 0) {
    365 			c_delafter(el, size);
    366 			re_refresh_cursor(el);
    367 		} else  {
    368 			c_delbefore(el, -size);
    369 			el->el_line.cursor += size;
    370 		}
    371 	}
    372 	el->el_chared.c_vcmd.action = NOP;
    373 }
    374 
    375 
    376 /* cv__endword():
    377  *	Go to the end of this word according to vi
    378  */
    379 libedit_private wchar_t *
    380 cv__endword(EditLine *el, wchar_t *p, wchar_t *high, int n,
    381     int (*wtest)(EditLine *, wint_t))
    382 {
    383 	int test;
    384 
    385 	p++;
    386 
    387 	while (n--) {
    388 		while ((p < high) && iswspace(*p))
    389 			p++;
    390 
    391 		test = (*wtest)(el, *p);
    392 		while ((p < high) && (*wtest)(el, *p) == test)
    393 			p++;
    394 	}
    395 	p--;
    396 	return p;
    397 }
    398 
    399 /* ch_init():
    400  *	Initialize the character editor
    401  */
    402 libedit_private int
    403 ch_init(EditLine *el)
    404 {
    405 	el->el_line.buffer		= el_calloc(EL_BUFSIZ,
    406 	    sizeof(*el->el_line.buffer));
    407 	if (el->el_line.buffer == NULL)
    408 		return -1;
    409 
    410 	el->el_line.cursor		= el->el_line.buffer;
    411 	el->el_line.lastchar		= el->el_line.buffer;
    412 	el->el_line.limit		= &el->el_line.buffer[EL_BUFSIZ - EL_LEAVE];
    413 
    414 	el->el_chared.c_undo.buf	= el_calloc(EL_BUFSIZ,
    415 	    sizeof(*el->el_chared.c_undo.buf));
    416 	if (el->el_chared.c_undo.buf == NULL)
    417 		return -1;
    418 	el->el_chared.c_undo.len	= -1;
    419 	el->el_chared.c_undo.cursor	= 0;
    420 	el->el_chared.c_redo.buf	= el_calloc(EL_BUFSIZ,
    421 	    sizeof(*el->el_chared.c_redo.buf));
    422 	if (el->el_chared.c_redo.buf == NULL)
    423 		goto out;
    424 	el->el_chared.c_redo.pos	= el->el_chared.c_redo.buf;
    425 	el->el_chared.c_redo.lim	= el->el_chared.c_redo.buf + EL_BUFSIZ;
    426 	el->el_chared.c_redo.cmd	= ED_UNASSIGNED;
    427 
    428 	el->el_chared.c_vcmd.action	= NOP;
    429 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
    430 
    431 	el->el_chared.c_kill.buf	= el_calloc(EL_BUFSIZ,
    432 	    sizeof(*el->el_chared.c_kill.buf));
    433 	if (el->el_chared.c_kill.buf == NULL)
    434 		goto out;
    435 	el->el_chared.c_kill.mark	= el->el_line.buffer;
    436 	el->el_chared.c_kill.last	= el->el_chared.c_kill.buf;
    437 	el->el_chared.c_resizefun	= NULL;
    438 	el->el_chared.c_resizearg	= NULL;
    439 	el->el_chared.c_aliasfun	= NULL;
    440 	el->el_chared.c_aliasarg	= NULL;
    441 
    442 	el->el_map.current		= el->el_map.key;
    443 
    444 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
    445 	el->el_state.doingarg		= 0;
    446 	el->el_state.metanext		= 0;
    447 	el->el_state.argument		= 1;
    448 	el->el_state.lastcmd		= ED_UNASSIGNED;
    449 
    450 	return 0;
    451 out:
    452 	ch_end(el);
    453 	return -1;
    454 }
    455 
    456 /* ch_reset():
    457  *	Reset the character editor
    458  */
    459 libedit_private void
    460 ch_reset(EditLine *el)
    461 {
    462 	el->el_line.cursor		= el->el_line.buffer;
    463 	el->el_line.lastchar		= el->el_line.buffer;
    464 
    465 	el->el_chared.c_undo.len	= -1;
    466 	el->el_chared.c_undo.cursor	= 0;
    467 
    468 	el->el_chared.c_vcmd.action	= NOP;
    469 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
    470 
    471 	el->el_chared.c_kill.mark	= el->el_line.buffer;
    472 
    473 	el->el_map.current		= el->el_map.key;
    474 
    475 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
    476 	el->el_state.doingarg		= 0;
    477 	el->el_state.metanext		= 0;
    478 	el->el_state.argument		= 1;
    479 	el->el_state.lastcmd		= ED_UNASSIGNED;
    480 
    481 	el->el_history.eventno		= 0;
    482 }
    483 
    484 /* ch_enlargebufs():
    485  *	Enlarge line buffer to be able to hold twice as much characters.
    486  *	Returns 1 if successful, 0 if not.
    487  */
    488 libedit_private int
    489 ch_enlargebufs(EditLine *el, size_t addlen)
    490 {
    491 	size_t sz, newsz;
    492 	wchar_t *newbuffer, *oldbuf, *oldkbuf;
    493 
    494 	sz = (size_t)(el->el_line.limit - el->el_line.buffer + EL_LEAVE);
    495 	newsz = sz * 2;
    496 	/*
    497 	 * If newly required length is longer than current buffer, we need
    498 	 * to make the buffer big enough to hold both old and new stuff.
    499 	 */
    500 	if (addlen > sz) {
    501 		while(newsz - sz < addlen)
    502 			newsz *= 2;
    503 	}
    504 
    505 	/*
    506 	 * Reallocate line buffer.
    507 	 */
    508 	newbuffer = el_realloc(el->el_line.buffer, newsz * sizeof(*newbuffer));
    509 	if (!newbuffer)
    510 		return 0;
    511 
    512 	/* zero the newly added memory, leave old data in */
    513 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
    514 
    515 	oldbuf = el->el_line.buffer;
    516 
    517 	el->el_line.buffer = newbuffer;
    518 	el->el_line.cursor = newbuffer + (el->el_line.cursor - oldbuf);
    519 	el->el_line.lastchar = newbuffer + (el->el_line.lastchar - oldbuf);
    520 	/* don't set new size until all buffers are enlarged */
    521 	el->el_line.limit  = &newbuffer[sz - EL_LEAVE];
    522 
    523 	/*
    524 	 * Reallocate kill buffer.
    525 	 */
    526 	newbuffer = el_realloc(el->el_chared.c_kill.buf, newsz *
    527 	    sizeof(*newbuffer));
    528 	if (!newbuffer)
    529 		return 0;
    530 
    531 	/* zero the newly added memory, leave old data in */
    532 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
    533 
    534 	oldkbuf = el->el_chared.c_kill.buf;
    535 
    536 	el->el_chared.c_kill.buf = newbuffer;
    537 	el->el_chared.c_kill.last = newbuffer +
    538 					(el->el_chared.c_kill.last - oldkbuf);
    539 	el->el_chared.c_kill.mark = el->el_line.buffer +
    540 					(el->el_chared.c_kill.mark - oldbuf);
    541 
    542 	/*
    543 	 * Reallocate undo buffer.
    544 	 */
    545 	newbuffer = el_realloc(el->el_chared.c_undo.buf,
    546 	    newsz * sizeof(*newbuffer));
    547 	if (!newbuffer)
    548 		return 0;
    549 
    550 	/* zero the newly added memory, leave old data in */
    551 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
    552 	el->el_chared.c_undo.buf = newbuffer;
    553 
    554 	newbuffer = el_realloc(el->el_chared.c_redo.buf,
    555 	    newsz * sizeof(*newbuffer));
    556 	if (!newbuffer)
    557 		return 0;
    558 	el->el_chared.c_redo.pos = newbuffer +
    559 			(el->el_chared.c_redo.pos - el->el_chared.c_redo.buf);
    560 	el->el_chared.c_redo.lim = newbuffer +
    561 			(el->el_chared.c_redo.lim - el->el_chared.c_redo.buf);
    562 	el->el_chared.c_redo.buf = newbuffer;
    563 
    564 	if (!hist_enlargebuf(el, sz, newsz))
    565 		return 0;
    566 
    567 	/* Safe to set enlarged buffer size */
    568 	el->el_line.limit  = &el->el_line.buffer[newsz - EL_LEAVE];
    569 	if (el->el_chared.c_resizefun)
    570 		(*el->el_chared.c_resizefun)(el, el->el_chared.c_resizearg);
    571 	return 1;
    572 }
    573 
    574 /* ch_end():
    575  *	Free the data structures used by the editor
    576  */
    577 libedit_private void
    578 ch_end(EditLine *el)
    579 {
    580 	el_free(el->el_line.buffer);
    581 	el->el_line.buffer = NULL;
    582 	el->el_line.limit = NULL;
    583 	el_free(el->el_chared.c_undo.buf);
    584 	el->el_chared.c_undo.buf = NULL;
    585 	el_free(el->el_chared.c_redo.buf);
    586 	el->el_chared.c_redo.buf = NULL;
    587 	el->el_chared.c_redo.pos = NULL;
    588 	el->el_chared.c_redo.lim = NULL;
    589 	el->el_chared.c_redo.cmd = ED_UNASSIGNED;
    590 	el_free(el->el_chared.c_kill.buf);
    591 	el->el_chared.c_kill.buf = NULL;
    592 	ch_reset(el);
    593 }
    594 
    595 
    596 /* el_insertstr():
    597  *	Insert string at cursor
    598  */
    599 int
    600 el_winsertstr(EditLine *el, const wchar_t *s)
    601 {
    602 	size_t len;
    603 
    604 	if (s == NULL || (len = wcslen(s)) == 0)
    605 		return -1;
    606 	if (el->el_line.lastchar + len >= el->el_line.limit) {
    607 		if (!ch_enlargebufs(el, len))
    608 			return -1;
    609 	}
    610 
    611 	c_insert(el, (int)len);
    612 	while (*s)
    613 		*el->el_line.cursor++ = *s++;
    614 	return 0;
    615 }
    616 
    617 
    618 /* el_deletestr():
    619  *	Delete num characters before the cursor
    620  */
    621 void
    622 el_deletestr(EditLine *el, int n)
    623 {
    624 	if (n <= 0)
    625 		return;
    626 
    627 	if (el->el_line.cursor < &el->el_line.buffer[n])
    628 		return;
    629 
    630 	c_delbefore(el, n);		/* delete before dot */
    631 	el->el_line.cursor -= n;
    632 	if (el->el_line.cursor < el->el_line.buffer)
    633 		el->el_line.cursor = el->el_line.buffer;
    634 }
    635 
    636 /* el_deletestr1():
    637  *	Delete characters between start and end
    638  */
    639 int
    640 el_deletestr1(EditLine *el, int start, int end)
    641 {
    642 	size_t line_length, len;
    643 	wchar_t *p1, *p2;
    644 
    645 	if (end <= start)
    646 		return 0;
    647 
    648 	line_length = (size_t)(el->el_line.lastchar - el->el_line.buffer);
    649 
    650 	if (start >= (int)line_length || end >= (int)line_length)
    651 		return 0;
    652 
    653 	len = (size_t)(end - start);
    654 	if (len > line_length - (size_t)end)
    655 		len = line_length - (size_t)end;
    656 
    657 	p1 = el->el_line.buffer + start;
    658 	p2 = el->el_line.buffer + end;
    659 	for (size_t i = 0; i < len; i++) {
    660 		*p1++ = *p2++;
    661 		el->el_line.lastchar--;
    662 	}
    663 
    664 	if (el->el_line.cursor < el->el_line.buffer)
    665 		el->el_line.cursor = el->el_line.buffer;
    666 
    667 	return end - start;
    668 }
    669 
    670 /* el_wreplacestr():
    671  *	Replace the contents of the line with the provided string
    672  */
    673 int
    674 el_wreplacestr(EditLine *el, const wchar_t *s)
    675 {
    676 	size_t len;
    677 	wchar_t * p;
    678 
    679 	if (s == NULL || (len = wcslen(s)) == 0)
    680 		return -1;
    681 
    682 	if (el->el_line.buffer + len >= el->el_line.limit) {
    683 		if (!ch_enlargebufs(el, len))
    684 			return -1;
    685 	}
    686 
    687 	p = el->el_line.buffer;
    688 	for (size_t i = 0; i < len; i++)
    689 		*p++ = *s++;
    690 
    691 	el->el_line.buffer[len] = '\0';
    692 	el->el_line.lastchar = el->el_line.buffer + len;
    693 	if (el->el_line.cursor > el->el_line.lastchar)
    694 		el->el_line.cursor = el->el_line.lastchar;
    695 
    696 	return 0;
    697 }
    698 
    699 /* el_cursor():
    700  *	Move the cursor to the left or the right of the current position
    701  */
    702 int
    703 el_cursor(EditLine *el, int n)
    704 {
    705 	if (n == 0)
    706 		goto out;
    707 
    708 	el->el_line.cursor += n;
    709 
    710 	if (el->el_line.cursor < el->el_line.buffer)
    711 		el->el_line.cursor = el->el_line.buffer;
    712 	if (el->el_line.cursor > el->el_line.lastchar)
    713 		el->el_line.cursor = el->el_line.lastchar;
    714 out:
    715 	return (int)(el->el_line.cursor - el->el_line.buffer);
    716 }
    717 
    718 /* c_gets():
    719  *	Get a string
    720  */
    721 libedit_private int
    722 c_gets(EditLine *el, wchar_t *buf, const wchar_t *prompt)
    723 {
    724 	ssize_t len;
    725 	wchar_t *cp = el->el_line.buffer, ch;
    726 
    727 	if (prompt) {
    728 		len = (ssize_t)wcslen(prompt);
    729 		(void)memcpy(cp, prompt, (size_t)len * sizeof(*cp));
    730 		cp += len;
    731 	}
    732 	len = 0;
    733 
    734 	for (;;) {
    735 		el->el_line.cursor = cp;
    736 		*cp = ' ';
    737 		el->el_line.lastchar = cp + 1;
    738 		re_refresh(el);
    739 
    740 		if (el_wgetc(el, &ch) != 1) {
    741 			ed_end_of_file(el, 0);
    742 			len = -1;
    743 			break;
    744 		}
    745 
    746 		switch (ch) {
    747 
    748 		case L'\b':	/* Delete and backspace */
    749 		case 0177:
    750 			if (len == 0) {
    751 				len = -1;
    752 				break;
    753 			}
    754 			len--;
    755 			cp--;
    756 			continue;
    757 
    758 		case 0033:	/* ESC */
    759 		case L'\r':	/* Newline */
    760 		case L'\n':
    761 			buf[len] = ch;
    762 			break;
    763 
    764 		default:
    765 			if (len >= (ssize_t)(EL_BUFSIZ - 16))
    766 				terminal_beep(el);
    767 			else {
    768 				buf[len++] = ch;
    769 				*cp++ = ch;
    770 			}
    771 			continue;
    772 		}
    773 		break;
    774 	}
    775 
    776 	el->el_line.buffer[0] = '\0';
    777 	el->el_line.lastchar = el->el_line.buffer;
    778 	el->el_line.cursor = el->el_line.buffer;
    779 	return (int)len;
    780 }
    781 
    782 
    783 /* c_hpos():
    784  *	Return the current horizontal position of the cursor
    785  */
    786 libedit_private int
    787 c_hpos(EditLine *el)
    788 {
    789 	wchar_t *ptr;
    790 
    791 	/*
    792 	 * Find how many characters till the beginning of this line.
    793 	 */
    794 	if (el->el_line.cursor == el->el_line.buffer)
    795 		return 0;
    796 	else {
    797 		for (ptr = el->el_line.cursor - 1;
    798 		     ptr >= el->el_line.buffer && *ptr != '\n';
    799 		     ptr--)
    800 			continue;
    801 		return (int)(el->el_line.cursor - ptr - 1);
    802 	}
    803 }
    804 
    805 libedit_private int
    806 ch_resizefun(EditLine *el, el_zfunc_t f, void *a)
    807 {
    808 	el->el_chared.c_resizefun = f;
    809 	el->el_chared.c_resizearg = a;
    810 	return 0;
    811 }
    812 
    813 libedit_private int
    814 ch_aliasfun(EditLine *el, el_afunc_t f, void *a)
    815 {
    816 	el->el_chared.c_aliasfun = f;
    817 	el->el_chared.c_aliasarg = a;
    818 	return 0;
    819 }
    820