xref: /freebsd/contrib/libedit/chared.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*	$NetBSD: chared.c,v 1.63 2022/10/30 19:11:31 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 1.63 2022/10/30 19:11:31 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(wint_t p)
206 {
207 	return iswalnum(p) || wcschr(L"*?_-.[]~=", 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(wint_t p)
216 {
217 	if (iswalnum(p) || p == L'_')
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(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(wchar_t *p, wchar_t *low, int n, int (*wtest)(wint_t))
240 {
241 	p--;
242 
243 	while (n--) {
244 		while ((p >= low) && !(*wtest)(*p))
245 			p--;
246 		while ((p >= low) && (*wtest)(*p))
247 			p--;
248 	}
249 
250 	/* cp now points to one character before the word */
251 	p++;
252 	if (p < low)
253 		p = low;
254 	/* cp now points where we want it */
255 	return p;
256 }
257 
258 
259 /* c__next_word():
260  *	Find the next word
261  */
262 libedit_private wchar_t *
263 c__next_word(wchar_t *p, wchar_t *high, int n, int (*wtest)(wint_t))
264 {
265 	while (n--) {
266 		while ((p < high) && !(*wtest)(*p))
267 			p++;
268 		while ((p < high) && (*wtest)(*p))
269 			p++;
270 	}
271 	if (p > high)
272 		p = high;
273 	/* p now points where we want it */
274 	return p;
275 }
276 
277 /* cv_next_word():
278  *	Find the next word vi style
279  */
280 libedit_private wchar_t *
281 cv_next_word(EditLine *el, wchar_t *p, wchar_t *high, int n,
282     int (*wtest)(wint_t))
283 {
284 	int test;
285 
286 	while (n--) {
287 		test = (*wtest)(*p);
288 		while ((p < high) && (*wtest)(*p) == test)
289 			p++;
290 		/*
291 		 * vi historically deletes with cw only the word preserving the
292 		 * trailing whitespace! This is not what 'w' does..
293 		 */
294 		if (n || el->el_chared.c_vcmd.action != (DELETE|INSERT))
295 			while ((p < high) && iswspace(*p))
296 				p++;
297 	}
298 
299 	/* p now points where we want it */
300 	if (p > high)
301 		return high;
302 	else
303 		return p;
304 }
305 
306 
307 /* cv_prev_word():
308  *	Find the previous word vi style
309  */
310 libedit_private wchar_t *
311 cv_prev_word(wchar_t *p, wchar_t *low, int n, int (*wtest)(wint_t))
312 {
313 	int test;
314 
315 	p--;
316 	while (n--) {
317 		while ((p > low) && iswspace(*p))
318 			p--;
319 		test = (*wtest)(*p);
320 		while ((p >= low) && (*wtest)(*p) == test)
321 			p--;
322 	}
323 	p++;
324 
325 	/* p now points where we want it */
326 	if (p < low)
327 		return low;
328 	else
329 		return p;
330 }
331 
332 
333 /* cv_delfini():
334  *	Finish vi delete action
335  */
336 libedit_private void
337 cv_delfini(EditLine *el)
338 {
339 	int size;
340 	int action = el->el_chared.c_vcmd.action;
341 
342 	if (action & INSERT)
343 		el->el_map.current = el->el_map.key;
344 
345 	if (el->el_chared.c_vcmd.pos == 0)
346 		/* sanity */
347 		return;
348 
349 	size = (int)(el->el_line.cursor - el->el_chared.c_vcmd.pos);
350 	if (size == 0)
351 		size = 1;
352 	el->el_line.cursor = el->el_chared.c_vcmd.pos;
353 	if (action & YANK) {
354 		if (size > 0)
355 			cv_yank(el, el->el_line.cursor, size);
356 		else
357 			cv_yank(el, el->el_line.cursor + size, -size);
358 	} else {
359 		if (size > 0) {
360 			c_delafter(el, size);
361 			re_refresh_cursor(el);
362 		} else  {
363 			c_delbefore(el, -size);
364 			el->el_line.cursor += size;
365 		}
366 	}
367 	el->el_chared.c_vcmd.action = NOP;
368 }
369 
370 
371 /* cv__endword():
372  *	Go to the end of this word according to vi
373  */
374 libedit_private wchar_t *
375 cv__endword(wchar_t *p, wchar_t *high, int n, int (*wtest)(wint_t))
376 {
377 	int test;
378 
379 	p++;
380 
381 	while (n--) {
382 		while ((p < high) && iswspace(*p))
383 			p++;
384 
385 		test = (*wtest)(*p);
386 		while ((p < high) && (*wtest)(*p) == test)
387 			p++;
388 	}
389 	p--;
390 	return p;
391 }
392 
393 /* ch_init():
394  *	Initialize the character editor
395  */
396 libedit_private int
397 ch_init(EditLine *el)
398 {
399 	el->el_line.buffer		= el_calloc(EL_BUFSIZ,
400 	    sizeof(*el->el_line.buffer));
401 	if (el->el_line.buffer == NULL)
402 		return -1;
403 
404 	el->el_line.cursor		= el->el_line.buffer;
405 	el->el_line.lastchar		= el->el_line.buffer;
406 	el->el_line.limit		= &el->el_line.buffer[EL_BUFSIZ - EL_LEAVE];
407 
408 	el->el_chared.c_undo.buf	= el_calloc(EL_BUFSIZ,
409 	    sizeof(*el->el_chared.c_undo.buf));
410 	if (el->el_chared.c_undo.buf == NULL)
411 		return -1;
412 	el->el_chared.c_undo.len	= -1;
413 	el->el_chared.c_undo.cursor	= 0;
414 	el->el_chared.c_redo.buf	= el_calloc(EL_BUFSIZ,
415 	    sizeof(*el->el_chared.c_redo.buf));
416 	if (el->el_chared.c_redo.buf == NULL)
417 		goto out;
418 	el->el_chared.c_redo.pos	= el->el_chared.c_redo.buf;
419 	el->el_chared.c_redo.lim	= el->el_chared.c_redo.buf + EL_BUFSIZ;
420 	el->el_chared.c_redo.cmd	= ED_UNASSIGNED;
421 
422 	el->el_chared.c_vcmd.action	= NOP;
423 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
424 
425 	el->el_chared.c_kill.buf	= el_calloc(EL_BUFSIZ,
426 	    sizeof(*el->el_chared.c_kill.buf));
427 	if (el->el_chared.c_kill.buf == NULL)
428 		goto out;
429 	el->el_chared.c_kill.mark	= el->el_line.buffer;
430 	el->el_chared.c_kill.last	= el->el_chared.c_kill.buf;
431 	el->el_chared.c_resizefun	= NULL;
432 	el->el_chared.c_resizearg	= NULL;
433 	el->el_chared.c_aliasfun	= NULL;
434 	el->el_chared.c_aliasarg	= NULL;
435 
436 	el->el_map.current		= el->el_map.key;
437 
438 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
439 	el->el_state.doingarg		= 0;
440 	el->el_state.metanext		= 0;
441 	el->el_state.argument		= 1;
442 	el->el_state.lastcmd		= ED_UNASSIGNED;
443 
444 	return 0;
445 out:
446 	ch_end(el);
447 	return -1;
448 }
449 
450 /* ch_reset():
451  *	Reset the character editor
452  */
453 libedit_private void
454 ch_reset(EditLine *el)
455 {
456 	el->el_line.cursor		= el->el_line.buffer;
457 	el->el_line.lastchar		= el->el_line.buffer;
458 
459 	el->el_chared.c_undo.len	= -1;
460 	el->el_chared.c_undo.cursor	= 0;
461 
462 	el->el_chared.c_vcmd.action	= NOP;
463 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
464 
465 	el->el_chared.c_kill.mark	= el->el_line.buffer;
466 
467 	el->el_map.current		= el->el_map.key;
468 
469 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
470 	el->el_state.doingarg		= 0;
471 	el->el_state.metanext		= 0;
472 	el->el_state.argument		= 1;
473 	el->el_state.lastcmd		= ED_UNASSIGNED;
474 
475 	el->el_history.eventno		= 0;
476 }
477 
478 /* ch_enlargebufs():
479  *	Enlarge line buffer to be able to hold twice as much characters.
480  *	Returns 1 if successful, 0 if not.
481  */
482 libedit_private int
483 ch_enlargebufs(EditLine *el, size_t addlen)
484 {
485 	size_t sz, newsz;
486 	wchar_t *newbuffer, *oldbuf, *oldkbuf;
487 
488 	sz = (size_t)(el->el_line.limit - el->el_line.buffer + EL_LEAVE);
489 	newsz = sz * 2;
490 	/*
491 	 * If newly required length is longer than current buffer, we need
492 	 * to make the buffer big enough to hold both old and new stuff.
493 	 */
494 	if (addlen > sz) {
495 		while(newsz - sz < addlen)
496 			newsz *= 2;
497 	}
498 
499 	/*
500 	 * Reallocate line buffer.
501 	 */
502 	newbuffer = el_realloc(el->el_line.buffer, newsz * sizeof(*newbuffer));
503 	if (!newbuffer)
504 		return 0;
505 
506 	/* zero the newly added memory, leave old data in */
507 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
508 
509 	oldbuf = el->el_line.buffer;
510 
511 	el->el_line.buffer = newbuffer;
512 	el->el_line.cursor = newbuffer + (el->el_line.cursor - oldbuf);
513 	el->el_line.lastchar = newbuffer + (el->el_line.lastchar - oldbuf);
514 	/* don't set new size until all buffers are enlarged */
515 	el->el_line.limit  = &newbuffer[sz - EL_LEAVE];
516 
517 	/*
518 	 * Reallocate kill buffer.
519 	 */
520 	newbuffer = el_realloc(el->el_chared.c_kill.buf, newsz *
521 	    sizeof(*newbuffer));
522 	if (!newbuffer)
523 		return 0;
524 
525 	/* zero the newly added memory, leave old data in */
526 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
527 
528 	oldkbuf = el->el_chared.c_kill.buf;
529 
530 	el->el_chared.c_kill.buf = newbuffer;
531 	el->el_chared.c_kill.last = newbuffer +
532 					(el->el_chared.c_kill.last - oldkbuf);
533 	el->el_chared.c_kill.mark = el->el_line.buffer +
534 					(el->el_chared.c_kill.mark - oldbuf);
535 
536 	/*
537 	 * Reallocate undo buffer.
538 	 */
539 	newbuffer = el_realloc(el->el_chared.c_undo.buf,
540 	    newsz * sizeof(*newbuffer));
541 	if (!newbuffer)
542 		return 0;
543 
544 	/* zero the newly added memory, leave old data in */
545 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
546 	el->el_chared.c_undo.buf = newbuffer;
547 
548 	newbuffer = el_realloc(el->el_chared.c_redo.buf,
549 	    newsz * sizeof(*newbuffer));
550 	if (!newbuffer)
551 		return 0;
552 	el->el_chared.c_redo.pos = newbuffer +
553 			(el->el_chared.c_redo.pos - el->el_chared.c_redo.buf);
554 	el->el_chared.c_redo.lim = newbuffer +
555 			(el->el_chared.c_redo.lim - el->el_chared.c_redo.buf);
556 	el->el_chared.c_redo.buf = newbuffer;
557 
558 	if (!hist_enlargebuf(el, sz, newsz))
559 		return 0;
560 
561 	/* Safe to set enlarged buffer size */
562 	el->el_line.limit  = &el->el_line.buffer[newsz - EL_LEAVE];
563 	if (el->el_chared.c_resizefun)
564 		(*el->el_chared.c_resizefun)(el, el->el_chared.c_resizearg);
565 	return 1;
566 }
567 
568 /* ch_end():
569  *	Free the data structures used by the editor
570  */
571 libedit_private void
572 ch_end(EditLine *el)
573 {
574 	el_free(el->el_line.buffer);
575 	el->el_line.buffer = NULL;
576 	el->el_line.limit = NULL;
577 	el_free(el->el_chared.c_undo.buf);
578 	el->el_chared.c_undo.buf = NULL;
579 	el_free(el->el_chared.c_redo.buf);
580 	el->el_chared.c_redo.buf = NULL;
581 	el->el_chared.c_redo.pos = NULL;
582 	el->el_chared.c_redo.lim = NULL;
583 	el->el_chared.c_redo.cmd = ED_UNASSIGNED;
584 	el_free(el->el_chared.c_kill.buf);
585 	el->el_chared.c_kill.buf = NULL;
586 	ch_reset(el);
587 }
588 
589 
590 /* el_insertstr():
591  *	Insert string at cursor
592  */
593 int
594 el_winsertstr(EditLine *el, const wchar_t *s)
595 {
596 	size_t len;
597 
598 	if (s == NULL || (len = wcslen(s)) == 0)
599 		return -1;
600 	if (el->el_line.lastchar + len >= el->el_line.limit) {
601 		if (!ch_enlargebufs(el, len))
602 			return -1;
603 	}
604 
605 	c_insert(el, (int)len);
606 	while (*s)
607 		*el->el_line.cursor++ = *s++;
608 	return 0;
609 }
610 
611 
612 /* el_deletestr():
613  *	Delete num characters before the cursor
614  */
615 void
616 el_deletestr(EditLine *el, int n)
617 {
618 	if (n <= 0)
619 		return;
620 
621 	if (el->el_line.cursor < &el->el_line.buffer[n])
622 		return;
623 
624 	c_delbefore(el, n);		/* delete before dot */
625 	el->el_line.cursor -= n;
626 	if (el->el_line.cursor < el->el_line.buffer)
627 		el->el_line.cursor = el->el_line.buffer;
628 }
629 
630 /* el_deletestr1():
631  *	Delete characters between start and end
632  */
633 int
634 el_deletestr1(EditLine *el, int start, int end)
635 {
636 	size_t line_length, len;
637 	wchar_t *p1, *p2;
638 
639 	if (end <= start)
640 		return 0;
641 
642 	line_length = (size_t)(el->el_line.lastchar - el->el_line.buffer);
643 
644 	if (start >= (int)line_length || end >= (int)line_length)
645 		return 0;
646 
647 	len = (size_t)(end - start);
648 	if (len > line_length - (size_t)end)
649 		len = line_length - (size_t)end;
650 
651 	p1 = el->el_line.buffer + start;
652 	p2 = el->el_line.buffer + end;
653 	for (size_t i = 0; i < len; i++) {
654 		*p1++ = *p2++;
655 		el->el_line.lastchar--;
656 	}
657 
658 	if (el->el_line.cursor < el->el_line.buffer)
659 		el->el_line.cursor = el->el_line.buffer;
660 
661 	return end - start;
662 }
663 
664 /* el_wreplacestr():
665  *	Replace the contents of the line with the provided string
666  */
667 int
668 el_wreplacestr(EditLine *el, const wchar_t *s)
669 {
670 	size_t len;
671 	wchar_t * p;
672 
673 	if (s == NULL || (len = wcslen(s)) == 0)
674 		return -1;
675 
676 	if (el->el_line.buffer + len >= el->el_line.limit) {
677 		if (!ch_enlargebufs(el, len))
678 			return -1;
679 	}
680 
681 	p = el->el_line.buffer;
682 	for (size_t i = 0; i < len; i++)
683 		*p++ = *s++;
684 
685 	el->el_line.buffer[len] = '\0';
686 	el->el_line.lastchar = el->el_line.buffer + len;
687 	if (el->el_line.cursor > el->el_line.lastchar)
688 		el->el_line.cursor = el->el_line.lastchar;
689 
690 	return 0;
691 }
692 
693 /* el_cursor():
694  *	Move the cursor to the left or the right of the current position
695  */
696 int
697 el_cursor(EditLine *el, int n)
698 {
699 	if (n == 0)
700 		goto out;
701 
702 	el->el_line.cursor += n;
703 
704 	if (el->el_line.cursor < el->el_line.buffer)
705 		el->el_line.cursor = el->el_line.buffer;
706 	if (el->el_line.cursor > el->el_line.lastchar)
707 		el->el_line.cursor = el->el_line.lastchar;
708 out:
709 	return (int)(el->el_line.cursor - el->el_line.buffer);
710 }
711 
712 /* c_gets():
713  *	Get a string
714  */
715 libedit_private int
716 c_gets(EditLine *el, wchar_t *buf, const wchar_t *prompt)
717 {
718 	ssize_t len;
719 	wchar_t *cp = el->el_line.buffer, ch;
720 
721 	if (prompt) {
722 		len = (ssize_t)wcslen(prompt);
723 		(void)memcpy(cp, prompt, (size_t)len * sizeof(*cp));
724 		cp += len;
725 	}
726 	len = 0;
727 
728 	for (;;) {
729 		el->el_line.cursor = cp;
730 		*cp = ' ';
731 		el->el_line.lastchar = cp + 1;
732 		re_refresh(el);
733 
734 		if (el_wgetc(el, &ch) != 1) {
735 			ed_end_of_file(el, 0);
736 			len = -1;
737 			break;
738 		}
739 
740 		switch (ch) {
741 
742 		case L'\b':	/* Delete and backspace */
743 		case 0177:
744 			if (len == 0) {
745 				len = -1;
746 				break;
747 			}
748 			len--;
749 			cp--;
750 			continue;
751 
752 		case 0033:	/* ESC */
753 		case L'\r':	/* Newline */
754 		case L'\n':
755 			buf[len] = ch;
756 			break;
757 
758 		default:
759 			if (len >= (ssize_t)(EL_BUFSIZ - 16))
760 				terminal_beep(el);
761 			else {
762 				buf[len++] = ch;
763 				*cp++ = ch;
764 			}
765 			continue;
766 		}
767 		break;
768 	}
769 
770 	el->el_line.buffer[0] = '\0';
771 	el->el_line.lastchar = el->el_line.buffer;
772 	el->el_line.cursor = el->el_line.buffer;
773 	return (int)len;
774 }
775 
776 
777 /* c_hpos():
778  *	Return the current horizontal position of the cursor
779  */
780 libedit_private int
781 c_hpos(EditLine *el)
782 {
783 	wchar_t *ptr;
784 
785 	/*
786 	 * Find how many characters till the beginning of this line.
787 	 */
788 	if (el->el_line.cursor == el->el_line.buffer)
789 		return 0;
790 	else {
791 		for (ptr = el->el_line.cursor - 1;
792 		     ptr >= el->el_line.buffer && *ptr != '\n';
793 		     ptr--)
794 			continue;
795 		return (int)(el->el_line.cursor - ptr - 1);
796 	}
797 }
798 
799 libedit_private int
800 ch_resizefun(EditLine *el, el_zfunc_t f, void *a)
801 {
802 	el->el_chared.c_resizefun = f;
803 	el->el_chared.c_resizearg = a;
804 	return 0;
805 }
806 
807 libedit_private int
808 ch_aliasfun(EditLine *el, el_afunc_t f, void *a)
809 {
810 	el->el_chared.c_aliasfun = f;
811 	el->el_chared.c_aliasarg = a;
812 	return 0;
813 }
814