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chared.c revision 1.27
      1 /*	$NetBSD: chared.c,v 1.27 2009/02/15 21:55:23 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 1.27 2009/02/15 21:55:23 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 = el->el_line.lastchar - el->el_line.buffer;
     67 	vu->len = size;
     68 	vu->cursor = (int)(el->el_line.cursor - el->el_line.buffer);
     69 	memcpy(vu->buf, el->el_line.buffer, size);
     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 	memcpy(k->buf, ptr, (size_t)size);
     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("*?_-.[]~=", 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)((unsigned char) *p))
    242 			p--;
    243 		while ((p >= low) && (*wtest)((unsigned char) *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)((unsigned char) *p))
    264 			p++;
    265 		while ((p < high) && (*wtest)((unsigned char) *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)((unsigned char) *p);
    284 		while ((p < high) && (*wtest)((unsigned char) *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((unsigned char) *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((unsigned char) *p))
    314 			p--;
    315 		test = (*wtest)((unsigned char) *p);
    316 		while ((p >= low) && (*wtest)((unsigned char) *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 #ifdef notdef
    330 /* c__number():
    331  *	Ignore character p points to, return number appearing after that.
    332  * 	A '$' by itself means a big number; "$-" is for negative; '^' means 1.
    333  * 	Return p pointing to last char used.
    334  */
    335 protected char *
    336 c__number(
    337     char *p,	/* character position */
    338     int *num,	/* Return value	*/
    339     int dval)	/* dval is the number to subtract from like $-3 */
    340 {
    341 	int i;
    342 	int sign = 1;
    343 
    344 	if (*++p == '^') {
    345 		*num = 1;
    346 		return (p);
    347 	}
    348 	if (*p == '$') {
    349 		if (*++p != '-') {
    350 			*num = 0x7fffffff;	/* Handle $ */
    351 			return (--p);
    352 		}
    353 		sign = -1;			/* Handle $- */
    354 		++p;
    355 	}
    356 	for (i = 0; isdigit((unsigned char) *p); i = 10 * i + *p++ - '0')
    357 		continue;
    358 	*num = (sign < 0 ? dval - i : i);
    359 	return (--p);
    360 }
    361 #endif
    362 
    363 /* cv_delfini():
    364  *	Finish vi delete action
    365  */
    366 protected void
    367 cv_delfini(EditLine *el)
    368 {
    369 	int size;
    370 	int action = el->el_chared.c_vcmd.action;
    371 
    372 	if (action & INSERT)
    373 		el->el_map.current = el->el_map.key;
    374 
    375 	if (el->el_chared.c_vcmd.pos == 0)
    376 		/* sanity */
    377 		return;
    378 
    379 	size = (int)(el->el_line.cursor - el->el_chared.c_vcmd.pos);
    380 	if (size == 0)
    381 		size = 1;
    382 	el->el_line.cursor = el->el_chared.c_vcmd.pos;
    383 	if (action & YANK) {
    384 		if (size > 0)
    385 			cv_yank(el, el->el_line.cursor, size);
    386 		else
    387 			cv_yank(el, el->el_line.cursor + size, -size);
    388 	} else {
    389 		if (size > 0) {
    390 			c_delafter(el, size);
    391 			re_refresh_cursor(el);
    392 		} else  {
    393 			c_delbefore(el, -size);
    394 			el->el_line.cursor += size;
    395 		}
    396 	}
    397 	el->el_chared.c_vcmd.action = NOP;
    398 }
    399 
    400 
    401 #ifdef notdef
    402 /* ce__endword():
    403  *	Go to the end of this word according to emacs
    404  */
    405 protected char *
    406 ce__endword(char *p, char *high, int n)
    407 {
    408 	p++;
    409 
    410 	while (n--) {
    411 		while ((p < high) && isspace((unsigned char) *p))
    412 			p++;
    413 		while ((p < high) && !isspace((unsigned char) *p))
    414 			p++;
    415 	}
    416 
    417 	p--;
    418 	return (p);
    419 }
    420 #endif
    421 
    422 
    423 /* cv__endword():
    424  *	Go to the end of this word according to vi
    425  */
    426 protected char *
    427 cv__endword(char *p, char *high, int n, int (*wtest)(int))
    428 {
    429 	int test;
    430 
    431 	p++;
    432 
    433 	while (n--) {
    434 		while ((p < high) && isspace((unsigned char) *p))
    435 			p++;
    436 
    437 		test = (*wtest)((unsigned char) *p);
    438 		while ((p < high) && (*wtest)((unsigned char) *p) == test)
    439 			p++;
    440 	}
    441 	p--;
    442 	return (p);
    443 }
    444 
    445 /* ch_init():
    446  *	Initialize the character editor
    447  */
    448 protected int
    449 ch_init(EditLine *el)
    450 {
    451 	c_macro_t *ma = &el->el_chared.c_macro;
    452 
    453 	el->el_line.buffer		= (char *) el_malloc(EL_BUFSIZ);
    454 	if (el->el_line.buffer == NULL)
    455 		return (-1);
    456 
    457 	(void) memset(el->el_line.buffer, 0, EL_BUFSIZ);
    458 	el->el_line.cursor		= el->el_line.buffer;
    459 	el->el_line.lastchar		= el->el_line.buffer;
    460 	el->el_line.limit		= &el->el_line.buffer[EL_BUFSIZ - EL_LEAVE];
    461 
    462 	el->el_chared.c_undo.buf	= (char *) el_malloc(EL_BUFSIZ);
    463 	if (el->el_chared.c_undo.buf == NULL)
    464 		return (-1);
    465 	(void) memset(el->el_chared.c_undo.buf, 0, EL_BUFSIZ);
    466 	el->el_chared.c_undo.len	= -1;
    467 	el->el_chared.c_undo.cursor	= 0;
    468 	el->el_chared.c_redo.buf	= (char *) el_malloc(EL_BUFSIZ);
    469 	if (el->el_chared.c_redo.buf == NULL)
    470 		return (-1);
    471 	el->el_chared.c_redo.pos	= el->el_chared.c_redo.buf;
    472 	el->el_chared.c_redo.lim	= el->el_chared.c_redo.buf + EL_BUFSIZ;
    473 	el->el_chared.c_redo.cmd	= ED_UNASSIGNED;
    474 
    475 	el->el_chared.c_vcmd.action	= NOP;
    476 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
    477 
    478 	el->el_chared.c_kill.buf	= (char *) el_malloc(EL_BUFSIZ);
    479 	if (el->el_chared.c_kill.buf == NULL)
    480 		return (-1);
    481 	(void) memset(el->el_chared.c_kill.buf, 0, EL_BUFSIZ);
    482 	el->el_chared.c_kill.mark	= el->el_line.buffer;
    483 	el->el_chared.c_kill.last	= el->el_chared.c_kill.buf;
    484 
    485 	el->el_map.current		= el->el_map.key;
    486 
    487 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
    488 	el->el_state.doingarg		= 0;
    489 	el->el_state.metanext		= 0;
    490 	el->el_state.argument		= 1;
    491 	el->el_state.lastcmd		= ED_UNASSIGNED;
    492 
    493 	ma->level	= -1;
    494 	ma->offset	= 0;
    495 	ma->macro	= (char **) el_malloc(EL_MAXMACRO * sizeof(char *));
    496 	if (ma->macro == NULL)
    497 		return (-1);
    498 	return (0);
    499 }
    500 
    501 /* ch_reset():
    502  *	Reset the character editor
    503  */
    504 protected void
    505 ch_reset(EditLine *el, int mclear)
    506 {
    507 	el->el_line.cursor		= el->el_line.buffer;
    508 	el->el_line.lastchar		= el->el_line.buffer;
    509 
    510 	el->el_chared.c_undo.len	= -1;
    511 	el->el_chared.c_undo.cursor	= 0;
    512 
    513 	el->el_chared.c_vcmd.action	= NOP;
    514 	el->el_chared.c_vcmd.pos	= el->el_line.buffer;
    515 
    516 	el->el_chared.c_kill.mark	= el->el_line.buffer;
    517 
    518 	el->el_map.current		= el->el_map.key;
    519 
    520 	el->el_state.inputmode		= MODE_INSERT; /* XXX: save a default */
    521 	el->el_state.doingarg		= 0;
    522 	el->el_state.metanext		= 0;
    523 	el->el_state.argument		= 1;
    524 	el->el_state.lastcmd		= ED_UNASSIGNED;
    525 
    526 	el->el_history.eventno		= 0;
    527 
    528 	if (mclear)
    529 		ch__clearmacro(el);
    530 }
    531 
    532 private void
    533 ch__clearmacro(EditLine *el)
    534 {
    535 	c_macro_t *ma = &el->el_chared.c_macro;
    536 	while (ma->level >= 0)
    537 		el_free((ptr_t)ma->macro[ma->level--]);
    538 }
    539 
    540 /* ch_enlargebufs():
    541  *	Enlarge line buffer to be able to hold twice as much characters.
    542  *	Returns 1 if successful, 0 if not.
    543  */
    544 protected int
    545 ch_enlargebufs(EditLine *el, size_t addlen)
    546 {
    547 	size_t sz, newsz;
    548 	char *newbuffer, *oldbuf, *oldkbuf;
    549 
    550 	sz = el->el_line.limit - el->el_line.buffer + EL_LEAVE;
    551 	newsz = sz * 2;
    552 	/*
    553 	 * If newly required length is longer than current buffer, we need
    554 	 * to make the buffer big enough to hold both old and new stuff.
    555 	 */
    556 	if (addlen > sz) {
    557 		while(newsz - sz < addlen)
    558 			newsz *= 2;
    559 	}
    560 
    561 	/*
    562 	 * Reallocate line buffer.
    563 	 */
    564 	newbuffer = el_realloc(el->el_line.buffer, newsz);
    565 	if (!newbuffer)
    566 		return 0;
    567 
    568 	/* zero the newly added memory, leave old data in */
    569 	(void) memset(&newbuffer[sz], 0, newsz - sz);
    570 
    571 	oldbuf = el->el_line.buffer;
    572 
    573 	el->el_line.buffer = newbuffer;
    574 	el->el_line.cursor = newbuffer + (el->el_line.cursor - oldbuf);
    575 	el->el_line.lastchar = newbuffer + (el->el_line.lastchar - oldbuf);
    576 	/* don't set new size until all buffers are enlarged */
    577 	el->el_line.limit  = &newbuffer[sz - EL_LEAVE];
    578 
    579 	/*
    580 	 * Reallocate kill buffer.
    581 	 */
    582 	newbuffer = el_realloc(el->el_chared.c_kill.buf, newsz);
    583 	if (!newbuffer)
    584 		return 0;
    585 
    586 	/* zero the newly added memory, leave old data in */
    587 	(void) memset(&newbuffer[sz], 0, newsz - sz);
    588 
    589 	oldkbuf = el->el_chared.c_kill.buf;
    590 
    591 	el->el_chared.c_kill.buf = newbuffer;
    592 	el->el_chared.c_kill.last = newbuffer +
    593 					(el->el_chared.c_kill.last - oldkbuf);
    594 	el->el_chared.c_kill.mark = el->el_line.buffer +
    595 					(el->el_chared.c_kill.mark - oldbuf);
    596 
    597 	/*
    598 	 * Reallocate undo buffer.
    599 	 */
    600 	newbuffer = el_realloc(el->el_chared.c_undo.buf, newsz);
    601 	if (!newbuffer)
    602 		return 0;
    603 
    604 	/* zero the newly added memory, leave old data in */
    605 	(void) memset(&newbuffer[sz], 0, newsz - sz);
    606 	el->el_chared.c_undo.buf = newbuffer;
    607 
    608 	newbuffer = el_realloc(el->el_chared.c_redo.buf, newsz);
    609 	if (!newbuffer)
    610 		return 0;
    611 	el->el_chared.c_redo.pos = newbuffer +
    612 			(el->el_chared.c_redo.pos - el->el_chared.c_redo.buf);
    613 	el->el_chared.c_redo.lim = newbuffer +
    614 			(el->el_chared.c_redo.lim - el->el_chared.c_redo.buf);
    615 	el->el_chared.c_redo.buf = newbuffer;
    616 
    617 	if (!hist_enlargebuf(el, sz, newsz))
    618 		return 0;
    619 
    620 	/* Safe to set enlarged buffer size */
    621 	el->el_line.limit  = &el->el_line.buffer[newsz - EL_LEAVE];
    622 	return 1;
    623 }
    624 
    625 /* ch_end():
    626  *	Free the data structures used by the editor
    627  */
    628 protected void
    629 ch_end(EditLine *el)
    630 {
    631 	el_free((ptr_t) el->el_line.buffer);
    632 	el->el_line.buffer = NULL;
    633 	el->el_line.limit = NULL;
    634 	el_free((ptr_t) el->el_chared.c_undo.buf);
    635 	el->el_chared.c_undo.buf = NULL;
    636 	el_free((ptr_t) el->el_chared.c_redo.buf);
    637 	el->el_chared.c_redo.buf = NULL;
    638 	el->el_chared.c_redo.pos = NULL;
    639 	el->el_chared.c_redo.lim = NULL;
    640 	el->el_chared.c_redo.cmd = ED_UNASSIGNED;
    641 	el_free((ptr_t) el->el_chared.c_kill.buf);
    642 	el->el_chared.c_kill.buf = NULL;
    643 	ch_reset(el, 1);
    644 	el_free((ptr_t) el->el_chared.c_macro.macro);
    645 	el->el_chared.c_macro.macro = NULL;
    646 }
    647 
    648 
    649 /* el_insertstr():
    650  *	Insert string at cursorI
    651  */
    652 public int
    653 el_insertstr(EditLine *el, const char *s)
    654 {
    655 	size_t len;
    656 
    657 	if ((len = strlen(s)) == 0)
    658 		return (-1);
    659 	if (el->el_line.lastchar + len >= el->el_line.limit) {
    660 		if (!ch_enlargebufs(el, len))
    661 			return (-1);
    662 	}
    663 
    664 	c_insert(el, (int)len);
    665 	while (*s)
    666 		*el->el_line.cursor++ = *s++;
    667 	return (0);
    668 }
    669 
    670 
    671 /* el_deletestr():
    672  *	Delete num characters before the cursor
    673  */
    674 public void
    675 el_deletestr(EditLine *el, int n)
    676 {
    677 	if (n <= 0)
    678 		return;
    679 
    680 	if (el->el_line.cursor < &el->el_line.buffer[n])
    681 		return;
    682 
    683 	c_delbefore(el, n);		/* delete before dot */
    684 	el->el_line.cursor -= n;
    685 	if (el->el_line.cursor < el->el_line.buffer)
    686 		el->el_line.cursor = el->el_line.buffer;
    687 }
    688 
    689 /* c_gets():
    690  *	Get a string
    691  */
    692 protected int
    693 c_gets(EditLine *el, char *buf, const char *prompt)
    694 {
    695 	char ch;
    696 	ssize_t len;
    697 	char *cp = el->el_line.buffer;
    698 
    699 	if (prompt) {
    700 		len = strlen(prompt);
    701 		memcpy(cp, prompt, (size_t)len);
    702 		cp += len;
    703 	}
    704 	len = 0;
    705 
    706 	for (;;) {
    707 		el->el_line.cursor = cp;
    708 		*cp = ' ';
    709 		el->el_line.lastchar = cp + 1;
    710 		re_refresh(el);
    711 
    712 		if (el_getc(el, &ch) != 1) {
    713 			ed_end_of_file(el, 0);
    714 			len = -1;
    715 			break;
    716 		}
    717 
    718 		switch (ch) {
    719 
    720 		case 0010:	/* Delete and backspace */
    721 		case 0177:
    722 			if (len == 0) {
    723 				len = -1;
    724 				break;
    725 			}
    726 			cp--;
    727 			continue;
    728 
    729 		case 0033:	/* ESC */
    730 		case '\r':	/* Newline */
    731 		case '\n':
    732 			buf[len] = ch;
    733 			break;
    734 
    735 		default:
    736 			if (len >= EL_BUFSIZ - 16)
    737 				term_beep(el);
    738 			else {
    739 				buf[len++] = ch;
    740 				*cp++ = ch;
    741 			}
    742 			continue;
    743 		}
    744 		break;
    745 	}
    746 
    747 	el->el_line.buffer[0] = '\0';
    748 	el->el_line.lastchar = el->el_line.buffer;
    749 	el->el_line.cursor = el->el_line.buffer;
    750 	return (int)len;
    751 }
    752 
    753 
    754 /* c_hpos():
    755  *	Return the current horizontal position of the cursor
    756  */
    757 protected int
    758 c_hpos(EditLine *el)
    759 {
    760 	char *ptr;
    761 
    762 	/*
    763 	 * Find how many characters till the beginning of this line.
    764 	 */
    765 	if (el->el_line.cursor == el->el_line.buffer)
    766 		return (0);
    767 	else {
    768 		for (ptr = el->el_line.cursor - 1;
    769 		     ptr >= el->el_line.buffer && *ptr != '\n';
    770 		     ptr--)
    771 			continue;
    772 		return (int)(el->el_line.cursor - ptr - 1);
    773 	}
    774 }
    775