Home | History | Annotate | Download | only in src
      1 /*	$NetBSD: chared.c,v 1.38 2013/07/12 17:48:29 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 1.38 2013/07/12 17:48:29 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 
    438 	el->el_map.current		= el->el_map.key;
    439 
    440 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
    441 	el->el_state.doingarg		= 0;
    442 	el->el_state.metanext		= 0;
    443 	el->el_state.argument		= 1;
    444 	el->el_state.lastcmd		= ED_UNASSIGNED;
    445 
    446 	ma->level	= -1;
    447 	ma->offset	= 0;
    448 	ma->macro	= el_malloc(EL_MAXMACRO * sizeof(*ma->macro));
    449 	if (ma->macro == NULL)
    450 		return -1;
    451 	return 0;
    452 }
    453 
    454 /* ch_reset():
    455  *	Reset the character editor
    456  */
    457 protected void
    458 ch_reset(EditLine *el, int mclear)
    459 {
    460 	el->el_line.cursor		= el->el_line.buffer;
    461 	el->el_line.lastchar		= el->el_line.buffer;
    462 
    463 	el->el_chared.c_undo.len	= -1;
    464 	el->el_chared.c_undo.cursor	= 0;
    465 
    466 	el->el_chared.c_vcmd.action	= NOP;
    467 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
    468 
    469 	el->el_chared.c_kill.mark	= el->el_line.buffer;
    470 
    471 	el->el_map.current		= el->el_map.key;
    472 
    473 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
    474 	el->el_state.doingarg		= 0;
    475 	el->el_state.metanext		= 0;
    476 	el->el_state.argument		= 1;
    477 	el->el_state.lastcmd		= ED_UNASSIGNED;
    478 
    479 	el->el_history.eventno		= 0;
    480 
    481 	if (mclear)
    482 		ch__clearmacro(el);
    483 }
    484 
    485 private void
    486 ch__clearmacro(EditLine *el)
    487 {
    488 	c_macro_t *ma = &el->el_chared.c_macro;
    489 	while (ma->level >= 0)
    490 		el_free(ma->macro[ma->level--]);
    491 }
    492 
    493 /* ch_enlargebufs():
    494  *	Enlarge line buffer to be able to hold twice as much characters.
    495  *	Returns 1 if successful, 0 if not.
    496  */
    497 protected int
    498 ch_enlargebufs(EditLine *el, size_t addlen)
    499 {
    500 	size_t sz, newsz;
    501 	Char *newbuffer, *oldbuf, *oldkbuf;
    502 
    503 	sz = (size_t)(el->el_line.limit - el->el_line.buffer + EL_LEAVE);
    504 	newsz = sz * 2;
    505 	/*
    506 	 * If newly required length is longer than current buffer, we need
    507 	 * to make the buffer big enough to hold both old and new stuff.
    508 	 */
    509 	if (addlen > sz) {
    510 		while(newsz - sz < addlen)
    511 			newsz *= 2;
    512 	}
    513 
    514 	/*
    515 	 * Reallocate line buffer.
    516 	 */
    517 	newbuffer = el_realloc(el->el_line.buffer, newsz * sizeof(*newbuffer));
    518 	if (!newbuffer)
    519 		return 0;
    520 
    521 	/* zero the newly added memory, leave old data in */
    522 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
    523 
    524 	oldbuf = el->el_line.buffer;
    525 
    526 	el->el_line.buffer = newbuffer;
    527 	el->el_line.cursor = newbuffer + (el->el_line.cursor - oldbuf);
    528 	el->el_line.lastchar = newbuffer + (el->el_line.lastchar - oldbuf);
    529 	/* don't set new size until all buffers are enlarged */
    530 	el->el_line.limit  = &newbuffer[sz - EL_LEAVE];
    531 
    532 	/*
    533 	 * Reallocate kill buffer.
    534 	 */
    535 	newbuffer = el_realloc(el->el_chared.c_kill.buf, newsz *
    536 	    sizeof(*newbuffer));
    537 	if (!newbuffer)
    538 		return 0;
    539 
    540 	/* zero the newly added memory, leave old data in */
    541 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
    542 
    543 	oldkbuf = el->el_chared.c_kill.buf;
    544 
    545 	el->el_chared.c_kill.buf = newbuffer;
    546 	el->el_chared.c_kill.last = newbuffer +
    547 					(el->el_chared.c_kill.last - oldkbuf);
    548 	el->el_chared.c_kill.mark = el->el_line.buffer +
    549 					(el->el_chared.c_kill.mark - oldbuf);
    550 
    551 	/*
    552 	 * Reallocate undo buffer.
    553 	 */
    554 	newbuffer = el_realloc(el->el_chared.c_undo.buf,
    555 	    newsz * sizeof(*newbuffer));
    556 	if (!newbuffer)
    557 		return 0;
    558 
    559 	/* zero the newly added memory, leave old data in */
    560 	(void) memset(&newbuffer[sz], 0, (newsz - sz) * sizeof(*newbuffer));
    561 	el->el_chared.c_undo.buf = newbuffer;
    562 
    563 	newbuffer = el_realloc(el->el_chared.c_redo.buf,
    564 	    newsz * sizeof(*newbuffer));
    565 	if (!newbuffer)
    566 		return 0;
    567 	el->el_chared.c_redo.pos = newbuffer +
    568 			(el->el_chared.c_redo.pos - el->el_chared.c_redo.buf);
    569 	el->el_chared.c_redo.lim = newbuffer +
    570 			(el->el_chared.c_redo.lim - el->el_chared.c_redo.buf);
    571 	el->el_chared.c_redo.buf = newbuffer;
    572 
    573 	if (!hist_enlargebuf(el, sz, newsz))
    574 		return 0;
    575 
    576 	/* Safe to set enlarged buffer size */
    577 	el->el_line.limit  = &el->el_line.buffer[newsz - EL_LEAVE];
    578 	if (el->el_chared.c_resizefun)
    579 		(*el->el_chared.c_resizefun)(el, el->el_chared.c_resizearg);
    580 	return 1;
    581 }
    582 
    583 /* ch_end():
    584  *	Free the data structures used by the editor
    585  */
    586 protected void
    587 ch_end(EditLine *el)
    588 {
    589 	el_free(el->el_line.buffer);
    590 	el->el_line.buffer = NULL;
    591 	el->el_line.limit = NULL;
    592 	el_free(el->el_chared.c_undo.buf);
    593 	el->el_chared.c_undo.buf = NULL;
    594 	el_free(el->el_chared.c_redo.buf);
    595 	el->el_chared.c_redo.buf = NULL;
    596 	el->el_chared.c_redo.pos = NULL;
    597 	el->el_chared.c_redo.lim = NULL;
    598 	el->el_chared.c_redo.cmd = ED_UNASSIGNED;
    599 	el_free(el->el_chared.c_kill.buf);
    600 	el->el_chared.c_kill.buf = NULL;
    601 	ch_reset(el, 1);
    602 	el_free(el->el_chared.c_macro.macro);
    603 	el->el_chared.c_macro.macro = NULL;
    604 }
    605 
    606 
    607 /* el_insertstr():
    608  *	Insert string at cursorI
    609  */
    610 public int
    611 FUN(el,insertstr)(EditLine *el, const Char *s)
    612 {
    613 	size_t len;
    614 
    615 	if (s == NULL || (len = Strlen(s)) == 0)
    616 		return -1;
    617 	if (el->el_line.lastchar + len >= el->el_line.limit) {
    618 		if (!ch_enlargebufs(el, len))
    619 			return -1;
    620 	}
    621 
    622 	c_insert(el, (int)len);
    623 	while (*s)
    624 		*el->el_line.cursor++ = *s++;
    625 	return 0;
    626 }
    627 
    628 
    629 /* el_deletestr():
    630  *	Delete num characters before the cursor
    631  */
    632 public void
    633 el_deletestr(EditLine *el, int n)
    634 {
    635 	if (n <= 0)
    636 		return;
    637 
    638 	if (el->el_line.cursor < &el->el_line.buffer[n])
    639 		return;
    640 
    641 	c_delbefore(el, n);		/* delete before dot */
    642 	el->el_line.cursor -= n;
    643 	if (el->el_line.cursor < el->el_line.buffer)
    644 		el->el_line.cursor = el->el_line.buffer;
    645 }
    646 
    647 /* el_cursor():
    648  *	Move the cursor to the left or the right of the current position
    649  */
    650 public int
    651 el_cursor(EditLine *el, int n)
    652 {
    653 	if (n == 0)
    654 		goto out;
    655 
    656 	el->el_line.cursor += n;
    657 
    658 	if (el->el_line.cursor < el->el_line.buffer)
    659 		el->el_line.cursor = el->el_line.buffer;
    660 	if (el->el_line.cursor > el->el_line.lastchar)
    661 		el->el_line.cursor = el->el_line.lastchar;
    662 out:
    663 	return el->el_line.cursor - el->el_line.buffer;
    664 }
    665 
    666 /* c_gets():
    667  *	Get a string
    668  */
    669 protected int
    670 c_gets(EditLine *el, Char *buf, const Char *prompt)
    671 {
    672 	Char ch;
    673 	ssize_t len;
    674 	Char *cp = el->el_line.buffer;
    675 
    676 	if (prompt) {
    677 		len = (ssize_t)Strlen(prompt);
    678 		(void)memcpy(cp, prompt, (size_t)len * sizeof(*cp));
    679 		cp += len;
    680 	}
    681 	len = 0;
    682 
    683 	for (;;) {
    684 		el->el_line.cursor = cp;
    685 		*cp = ' ';
    686 		el->el_line.lastchar = cp + 1;
    687 		re_refresh(el);
    688 
    689 		if (FUN(el,getc)(el, &ch) != 1) {
    690 			ed_end_of_file(el, 0);
    691 			len = -1;
    692 			break;
    693 		}
    694 
    695 		switch (ch) {
    696 
    697 		case 0010:	/* Delete and backspace */
    698 		case 0177:
    699 			if (len == 0) {
    700 				len = -1;
    701 				break;
    702 			}
    703 			cp--;
    704 			continue;
    705 
    706 		case 0033:	/* ESC */
    707 		case '\r':	/* Newline */
    708 		case '\n':
    709 			buf[len] = ch;
    710 			break;
    711 
    712 		default:
    713 			if (len >= (ssize_t)(EL_BUFSIZ - 16))
    714 				terminal_beep(el);
    715 			else {
    716 				buf[len++] = ch;
    717 				*cp++ = ch;
    718 			}
    719 			continue;
    720 		}
    721 		break;
    722 	}
    723 
    724 	el->el_line.buffer[0] = '\0';
    725 	el->el_line.lastchar = el->el_line.buffer;
    726 	el->el_line.cursor = el->el_line.buffer;
    727 	return (int)len;
    728 }
    729 
    730 
    731 /* c_hpos():
    732  *	Return the current horizontal position of the cursor
    733  */
    734 protected int
    735 c_hpos(EditLine *el)
    736 {
    737 	Char *ptr;
    738 
    739 	/*
    740 	 * Find how many characters till the beginning of this line.
    741 	 */
    742 	if (el->el_line.cursor == el->el_line.buffer)
    743 		return 0;
    744 	else {
    745 		for (ptr = el->el_line.cursor - 1;
    746 		     ptr >= el->el_line.buffer && *ptr != '\n';
    747 		     ptr--)
    748 			continue;
    749 		return (int)(el->el_line.cursor - ptr - 1);
    750 	}
    751 }
    752 
    753 protected int
    754 ch_resizefun(EditLine *el, el_zfunc_t f, void *a)
    755 {
    756 	el->el_chared.c_resizefun = f;
    757 	el->el_chared.c_resizearg = a;
    758 	return 0;
    759 }
    760