xref: /dragonfly/contrib/libedit/src/chared.c (revision cd1c6085)
1 /*	$NetBSD: chared.c,v 1.40 2014/06/18 18:12:28 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 1.40 2014/06/18 18:12:28 christos Exp $");
41 #endif
42 #endif /* not lint && not SCCSID */
43 
44 /*
45  * chared.c: Character editor utilities
46  */
47 #include <stdlib.h>
48 #include "el.h"
49 
50 private void ch__clearmacro (EditLine *);
51 
52 /* value to leave unused in line buffer */
53 #define	EL_LEAVE	2
54 
55 /* cv_undo():
56  *	Handle state for the vi undo command
57  */
58 protected void
59 cv_undo(EditLine *el)
60 {
61 	c_undo_t *vu = &el->el_chared.c_undo;
62 	c_redo_t *r = &el->el_chared.c_redo;
63 	size_t size;
64 
65 	/* Save entire line for undo */
66 	size = (size_t)(el->el_line.lastchar - el->el_line.buffer);
67 	vu->len = (ssize_t)size;
68 	vu->cursor = (int)(el->el_line.cursor - el->el_line.buffer);
69 	(void)memcpy(vu->buf, el->el_line.buffer, size * sizeof(*vu->buf));
70 
71 	/* save command info for redo */
72 	r->count = el->el_state.doingarg ? el->el_state.argument : 0;
73 	r->action = el->el_chared.c_vcmd.action;
74 	r->pos = r->buf;
75 	r->cmd = el->el_state.thiscmd;
76 	r->ch = el->el_state.thisch;
77 }
78 
79 /* cv_yank():
80  *	Save yank/delete data for paste
81  */
82 protected void
83 cv_yank(EditLine *el, const Char *ptr, int size)
84 {
85 	c_kill_t *k = &el->el_chared.c_kill;
86 
87 	(void)memcpy(k->buf, ptr, (size_t)size * sizeof(*k->buf));
88 	k->last = k->buf + size;
89 }
90 
91 
92 /* c_insert():
93  *	Insert num characters
94  */
95 protected void
96 c_insert(EditLine *el, int num)
97 {
98 	Char *cp;
99 
100 	if (el->el_line.lastchar + num >= el->el_line.limit) {
101 		if (!ch_enlargebufs(el, (size_t)num))
102 			return;		/* can't go past end of buffer */
103 	}
104 
105 	if (el->el_line.cursor < el->el_line.lastchar) {
106 		/* if I must move chars */
107 		for (cp = el->el_line.lastchar; cp >= el->el_line.cursor; cp--)
108 			cp[num] = *cp;
109 	}
110 	el->el_line.lastchar += num;
111 }
112 
113 
114 /* c_delafter():
115  *	Delete num characters after the cursor
116  */
117 protected void
118 c_delafter(EditLine *el, int num)
119 {
120 
121 	if (el->el_line.cursor + num > el->el_line.lastchar)
122 		num = (int)(el->el_line.lastchar - el->el_line.cursor);
123 
124 	if (el->el_map.current != el->el_map.emacs) {
125 		cv_undo(el);
126 		cv_yank(el, el->el_line.cursor, num);
127 	}
128 
129 	if (num > 0) {
130 		Char *cp;
131 
132 		for (cp = el->el_line.cursor; cp <= el->el_line.lastchar; cp++)
133 			*cp = cp[num];
134 
135 		el->el_line.lastchar -= num;
136 	}
137 }
138 
139 
140 /* c_delafter1():
141  *	Delete the character after the cursor, do not yank
142  */
143 protected void
144 c_delafter1(EditLine *el)
145 {
146 	Char *cp;
147 
148 	for (cp = el->el_line.cursor; cp <= el->el_line.lastchar; cp++)
149 		*cp = cp[1];
150 
151 	el->el_line.lastchar--;
152 }
153 
154 
155 /* c_delbefore():
156  *	Delete num characters before the cursor
157  */
158 protected void
159 c_delbefore(EditLine *el, int num)
160 {
161 
162 	if (el->el_line.cursor - num < el->el_line.buffer)
163 		num = (int)(el->el_line.cursor - el->el_line.buffer);
164 
165 	if (el->el_map.current != el->el_map.emacs) {
166 		cv_undo(el);
167 		cv_yank(el, el->el_line.cursor - num, num);
168 	}
169 
170 	if (num > 0) {
171 		Char *cp;
172 
173 		for (cp = el->el_line.cursor - num;
174 		    cp <= el->el_line.lastchar;
175 		    cp++)
176 			*cp = cp[num];
177 
178 		el->el_line.lastchar -= num;
179 	}
180 }
181 
182 
183 /* c_delbefore1():
184  *	Delete the character before the cursor, do not yank
185  */
186 protected void
187 c_delbefore1(EditLine *el)
188 {
189 	Char *cp;
190 
191 	for (cp = el->el_line.cursor - 1; cp <= el->el_line.lastchar; cp++)
192 		*cp = cp[1];
193 
194 	el->el_line.lastchar--;
195 }
196 
197 
198 /* ce__isword():
199  *	Return if p is part of a word according to emacs
200  */
201 protected int
202 ce__isword(Int p)
203 {
204 	return Isalnum(p) || Strchr(STR("*?_-.[]~="), p) != NULL;
205 }
206 
207 
208 /* cv__isword():
209  *	Return if p is part of a word according to vi
210  */
211 protected int
212 cv__isword(Int p)
213 {
214 	if (Isalnum(p) || p == '_')
215 		return 1;
216 	if (Isgraph(p))
217 		return 2;
218 	return 0;
219 }
220 
221 
222 /* cv__isWord():
223  *	Return if p is part of a big word according to vi
224  */
225 protected int
226 cv__isWord(Int p)
227 {
228 	return !Isspace(p);
229 }
230 
231 
232 /* c__prev_word():
233  *	Find the previous word
234  */
235 protected Char *
236 c__prev_word(Char *p, Char *low, int n, int (*wtest)(Int))
237 {
238 	p--;
239 
240 	while (n--) {
241 		while ((p >= low) && !(*wtest)(*p))
242 			p--;
243 		while ((p >= low) && (*wtest)(*p))
244 			p--;
245 	}
246 
247 	/* cp now points to one character before the word */
248 	p++;
249 	if (p < low)
250 		p = low;
251 	/* cp now points where we want it */
252 	return p;
253 }
254 
255 
256 /* c__next_word():
257  *	Find the next word
258  */
259 protected Char *
260 c__next_word(Char *p, Char *high, int n, int (*wtest)(Int))
261 {
262 	while (n--) {
263 		while ((p < high) && !(*wtest)(*p))
264 			p++;
265 		while ((p < high) && (*wtest)(*p))
266 			p++;
267 	}
268 	if (p > high)
269 		p = high;
270 	/* p now points where we want it */
271 	return p;
272 }
273 
274 /* cv_next_word():
275  *	Find the next word vi style
276  */
277 protected Char *
278 cv_next_word(EditLine *el, Char *p, Char *high, int n, int (*wtest)(Int))
279 {
280 	int test;
281 
282 	while (n--) {
283 		test = (*wtest)(*p);
284 		while ((p < high) && (*wtest)(*p) == test)
285 			p++;
286 		/*
287 		 * vi historically deletes with cw only the word preserving the
288 		 * trailing whitespace! This is not what 'w' does..
289 		 */
290 		if (n || el->el_chared.c_vcmd.action != (DELETE|INSERT))
291 			while ((p < high) && Isspace(*p))
292 				p++;
293 	}
294 
295 	/* p now points where we want it */
296 	if (p > high)
297 		return high;
298 	else
299 		return p;
300 }
301 
302 
303 /* cv_prev_word():
304  *	Find the previous word vi style
305  */
306 protected Char *
307 cv_prev_word(Char *p, Char *low, int n, int (*wtest)(Int))
308 {
309 	int test;
310 
311 	p--;
312 	while (n--) {
313 		while ((p > low) && Isspace(*p))
314 			p--;
315 		test = (*wtest)(*p);
316 		while ((p >= low) && (*wtest)(*p) == test)
317 			p--;
318 	}
319 	p++;
320 
321 	/* p now points where we want it */
322 	if (p < low)
323 		return low;
324 	else
325 		return p;
326 }
327 
328 
329 /* cv_delfini():
330  *	Finish vi delete action
331  */
332 protected void
333 cv_delfini(EditLine *el)
334 {
335 	int size;
336 	int action = el->el_chared.c_vcmd.action;
337 
338 	if (action & INSERT)
339 		el->el_map.current = el->el_map.key;
340 
341 	if (el->el_chared.c_vcmd.pos == 0)
342 		/* sanity */
343 		return;
344 
345 	size = (int)(el->el_line.cursor - el->el_chared.c_vcmd.pos);
346 	if (size == 0)
347 		size = 1;
348 	el->el_line.cursor = el->el_chared.c_vcmd.pos;
349 	if (action & YANK) {
350 		if (size > 0)
351 			cv_yank(el, el->el_line.cursor, size);
352 		else
353 			cv_yank(el, el->el_line.cursor + size, -size);
354 	} else {
355 		if (size > 0) {
356 			c_delafter(el, size);
357 			re_refresh_cursor(el);
358 		} else  {
359 			c_delbefore(el, -size);
360 			el->el_line.cursor += size;
361 		}
362 	}
363 	el->el_chared.c_vcmd.action = NOP;
364 }
365 
366 
367 /* cv__endword():
368  *	Go to the end of this word according to vi
369  */
370 protected Char *
371 cv__endword(Char *p, Char *high, int n, int (*wtest)(Int))
372 {
373 	int test;
374 
375 	p++;
376 
377 	while (n--) {
378 		while ((p < high) && Isspace(*p))
379 			p++;
380 
381 		test = (*wtest)(*p);
382 		while ((p < high) && (*wtest)(*p) == test)
383 			p++;
384 	}
385 	p--;
386 	return p;
387 }
388 
389 /* ch_init():
390  *	Initialize the character editor
391  */
392 protected int
393 ch_init(EditLine *el)
394 {
395 	c_macro_t *ma = &el->el_chared.c_macro;
396 
397 	el->el_line.buffer		= el_malloc(EL_BUFSIZ *
398 	    sizeof(*el->el_line.buffer));
399 	if (el->el_line.buffer == NULL)
400 		return -1;
401 
402 	(void) memset(el->el_line.buffer, 0, EL_BUFSIZ *
403 	    sizeof(*el->el_line.buffer));
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_malloc(EL_BUFSIZ *
409 	    sizeof(*el->el_chared.c_undo.buf));
410 	if (el->el_chared.c_undo.buf == NULL)
411 		return -1;
412 	(void) memset(el->el_chared.c_undo.buf, 0, EL_BUFSIZ *
413 	    sizeof(*el->el_chared.c_undo.buf));
414 	el->el_chared.c_undo.len	= -1;
415 	el->el_chared.c_undo.cursor	= 0;
416 	el->el_chared.c_redo.buf	= el_malloc(EL_BUFSIZ *
417 	    sizeof(*el->el_chared.c_redo.buf));
418 	if (el->el_chared.c_redo.buf == NULL)
419 		return -1;
420 	el->el_chared.c_redo.pos	= el->el_chared.c_redo.buf;
421 	el->el_chared.c_redo.lim	= el->el_chared.c_redo.buf + EL_BUFSIZ;
422 	el->el_chared.c_redo.cmd	= ED_UNASSIGNED;
423 
424 	el->el_chared.c_vcmd.action	= NOP;
425 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
426 
427 	el->el_chared.c_kill.buf	= el_malloc(EL_BUFSIZ *
428 	    sizeof(*el->el_chared.c_kill.buf));
429 	if (el->el_chared.c_kill.buf == NULL)
430 		return -1;
431 	(void) memset(el->el_chared.c_kill.buf, 0, EL_BUFSIZ *
432 	    sizeof(*el->el_chared.c_kill.buf));
433 	el->el_chared.c_kill.mark	= el->el_line.buffer;
434 	el->el_chared.c_kill.last	= el->el_chared.c_kill.buf;
435 	el->el_chared.c_resizefun	= NULL;
436 	el->el_chared.c_resizearg	= NULL;
437 	el->el_chared.c_aliasfun	= NULL;
438 	el->el_chared.c_aliasarg	= NULL;
439 
440 	el->el_map.current		= el->el_map.key;
441 
442 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
443 	el->el_state.doingarg		= 0;
444 	el->el_state.metanext		= 0;
445 	el->el_state.argument		= 1;
446 	el->el_state.lastcmd		= ED_UNASSIGNED;
447 
448 	ma->level	= -1;
449 	ma->offset	= 0;
450 	ma->macro	= el_malloc(EL_MAXMACRO * sizeof(*ma->macro));
451 	if (ma->macro == NULL)
452 		return -1;
453 	return 0;
454 }
455 
456 /* ch_reset():
457  *	Reset the character editor
458  */
459 protected void
460 ch_reset(EditLine *el, int mclear)
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 	if (mclear)
484 		ch__clearmacro(el);
485 }
486 
487 private void
488 ch__clearmacro(EditLine *el)
489 {
490 	c_macro_t *ma = &el->el_chared.c_macro;
491 	while (ma->level >= 0)
492 		el_free(ma->macro[ma->level--]);
493 }
494 
495 /* ch_enlargebufs():
496  *	Enlarge line buffer to be able to hold twice as much characters.
497  *	Returns 1 if successful, 0 if not.
498  */
499 protected int
500 ch_enlargebufs(EditLine *el, size_t addlen)
501 {
502 	size_t sz, newsz;
503 	Char *newbuffer, *oldbuf, *oldkbuf;
504 
505 	sz = (size_t)(el->el_line.limit - el->el_line.buffer + EL_LEAVE);
506 	newsz = sz * 2;
507 	/*
508 	 * If newly required length is longer than current buffer, we need
509 	 * to make the buffer big enough to hold both old and new stuff.
510 	 */
511 	if (addlen > sz) {
512 		while(newsz - sz < addlen)
513 			newsz *= 2;
514 	}
515 
516 	/*
517 	 * Reallocate line buffer.
518 	 */
519 	newbuffer = el_realloc(el->el_line.buffer, newsz * sizeof(*newbuffer));
520 	if (!newbuffer)
521 		return 0;
522 
523 	/* zero the newly added memory, leave old data in */
524 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
525 
526 	oldbuf = el->el_line.buffer;
527 
528 	el->el_line.buffer = newbuffer;
529 	el->el_line.cursor = newbuffer + (el->el_line.cursor - oldbuf);
530 	el->el_line.lastchar = newbuffer + (el->el_line.lastchar - oldbuf);
531 	/* don't set new size until all buffers are enlarged */
532 	el->el_line.limit  = &newbuffer[sz - EL_LEAVE];
533 
534 	/*
535 	 * Reallocate kill buffer.
536 	 */
537 	newbuffer = el_realloc(el->el_chared.c_kill.buf, newsz *
538 	    sizeof(*newbuffer));
539 	if (!newbuffer)
540 		return 0;
541 
542 	/* zero the newly added memory, leave old data in */
543 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
544 
545 	oldkbuf = el->el_chared.c_kill.buf;
546 
547 	el->el_chared.c_kill.buf = newbuffer;
548 	el->el_chared.c_kill.last = newbuffer +
549 					(el->el_chared.c_kill.last - oldkbuf);
550 	el->el_chared.c_kill.mark = el->el_line.buffer +
551 					(el->el_chared.c_kill.mark - oldbuf);
552 
553 	/*
554 	 * Reallocate undo buffer.
555 	 */
556 	newbuffer = el_realloc(el->el_chared.c_undo.buf,
557 	    newsz * sizeof(*newbuffer));
558 	if (!newbuffer)
559 		return 0;
560 
561 	/* zero the newly added memory, leave old data in */
562 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
563 	el->el_chared.c_undo.buf = newbuffer;
564 
565 	newbuffer = el_realloc(el->el_chared.c_redo.buf,
566 	    newsz * sizeof(*newbuffer));
567 	if (!newbuffer)
568 		return 0;
569 	el->el_chared.c_redo.pos = newbuffer +
570 			(el->el_chared.c_redo.pos - el->el_chared.c_redo.buf);
571 	el->el_chared.c_redo.lim = newbuffer +
572 			(el->el_chared.c_redo.lim - el->el_chared.c_redo.buf);
573 	el->el_chared.c_redo.buf = newbuffer;
574 
575 	if (!hist_enlargebuf(el, sz, newsz))
576 		return 0;
577 
578 	/* Safe to set enlarged buffer size */
579 	el->el_line.limit  = &el->el_line.buffer[newsz - EL_LEAVE];
580 	if (el->el_chared.c_resizefun)
581 		(*el->el_chared.c_resizefun)(el, el->el_chared.c_resizearg);
582 	return 1;
583 }
584 
585 /* ch_end():
586  *	Free the data structures used by the editor
587  */
588 protected void
589 ch_end(EditLine *el)
590 {
591 	el_free(el->el_line.buffer);
592 	el->el_line.buffer = NULL;
593 	el->el_line.limit = NULL;
594 	el_free(el->el_chared.c_undo.buf);
595 	el->el_chared.c_undo.buf = NULL;
596 	el_free(el->el_chared.c_redo.buf);
597 	el->el_chared.c_redo.buf = NULL;
598 	el->el_chared.c_redo.pos = NULL;
599 	el->el_chared.c_redo.lim = NULL;
600 	el->el_chared.c_redo.cmd = ED_UNASSIGNED;
601 	el_free(el->el_chared.c_kill.buf);
602 	el->el_chared.c_kill.buf = NULL;
603 	ch_reset(el, 1);
604 	el_free(el->el_chared.c_macro.macro);
605 	el->el_chared.c_macro.macro = NULL;
606 }
607 
608 
609 /* el_insertstr():
610  *	Insert string at cursorI
611  */
612 public int
613 FUN(el,insertstr)(EditLine *el, const Char *s)
614 {
615 	size_t len;
616 
617 	if (s == NULL || (len = Strlen(s)) == 0)
618 		return -1;
619 	if (el->el_line.lastchar + len >= el->el_line.limit) {
620 		if (!ch_enlargebufs(el, len))
621 			return -1;
622 	}
623 
624 	c_insert(el, (int)len);
625 	while (*s)
626 		*el->el_line.cursor++ = *s++;
627 	return 0;
628 }
629 
630 
631 /* el_deletestr():
632  *	Delete num characters before the cursor
633  */
634 public void
635 el_deletestr(EditLine *el, int n)
636 {
637 	if (n <= 0)
638 		return;
639 
640 	if (el->el_line.cursor < &el->el_line.buffer[n])
641 		return;
642 
643 	c_delbefore(el, n);		/* delete before dot */
644 	el->el_line.cursor -= n;
645 	if (el->el_line.cursor < el->el_line.buffer)
646 		el->el_line.cursor = el->el_line.buffer;
647 }
648 
649 /* el_cursor():
650  *	Move the cursor to the left or the right of the current position
651  */
652 public int
653 el_cursor(EditLine *el, int n)
654 {
655 	if (n == 0)
656 		goto out;
657 
658 	el->el_line.cursor += n;
659 
660 	if (el->el_line.cursor < el->el_line.buffer)
661 		el->el_line.cursor = el->el_line.buffer;
662 	if (el->el_line.cursor > el->el_line.lastchar)
663 		el->el_line.cursor = el->el_line.lastchar;
664 out:
665 	return (int)(el->el_line.cursor - el->el_line.buffer);
666 }
667 
668 /* c_gets():
669  *	Get a string
670  */
671 protected int
672 c_gets(EditLine *el, Char *buf, const Char *prompt)
673 {
674 	Char ch;
675 	ssize_t len;
676 	Char *cp = el->el_line.buffer;
677 
678 	if (prompt) {
679 		len = (ssize_t)Strlen(prompt);
680 		(void)memcpy(cp, prompt, (size_t)len * sizeof(*cp));
681 		cp += len;
682 	}
683 	len = 0;
684 
685 	for (;;) {
686 		el->el_line.cursor = cp;
687 		*cp = ' ';
688 		el->el_line.lastchar = cp + 1;
689 		re_refresh(el);
690 
691 		if (FUN(el,getc)(el, &ch) != 1) {
692 			ed_end_of_file(el, 0);
693 			len = -1;
694 			break;
695 		}
696 
697 		switch (ch) {
698 
699 		case 0010:	/* Delete and backspace */
700 		case 0177:
701 			if (len == 0) {
702 				len = -1;
703 				break;
704 			}
705 			cp--;
706 			continue;
707 
708 		case 0033:	/* ESC */
709 		case '\r':	/* Newline */
710 		case '\n':
711 			buf[len] = ch;
712 			break;
713 
714 		default:
715 			if (len >= (ssize_t)(EL_BUFSIZ - 16))
716 				terminal_beep(el);
717 			else {
718 				buf[len++] = ch;
719 				*cp++ = ch;
720 			}
721 			continue;
722 		}
723 		break;
724 	}
725 
726 	el->el_line.buffer[0] = '\0';
727 	el->el_line.lastchar = el->el_line.buffer;
728 	el->el_line.cursor = el->el_line.buffer;
729 	return (int)len;
730 }
731 
732 
733 /* c_hpos():
734  *	Return the current horizontal position of the cursor
735  */
736 protected int
737 c_hpos(EditLine *el)
738 {
739 	Char *ptr;
740 
741 	/*
742 	 * Find how many characters till the beginning of this line.
743 	 */
744 	if (el->el_line.cursor == el->el_line.buffer)
745 		return 0;
746 	else {
747 		for (ptr = el->el_line.cursor - 1;
748 		     ptr >= el->el_line.buffer && *ptr != '\n';
749 		     ptr--)
750 			continue;
751 		return (int)(el->el_line.cursor - ptr - 1);
752 	}
753 }
754 
755 protected int
756 ch_resizefun(EditLine *el, el_zfunc_t f, void *a)
757 {
758 	el->el_chared.c_resizefun = f;
759 	el->el_chared.c_resizearg = a;
760 	return 0;
761 }
762 
763 protected int
764 ch_aliasfun(EditLine *el, el_afunc_t f, void *a)
765 {
766 	el->el_chared.c_aliasfun = f;
767 	el->el_chared.c_aliasarg = a;
768 	return 0;
769 }
770