xref: /freebsd-12.1/lib/libedit/read.c (revision efd7a3dc)
1 /*	$NetBSD: read.c,v 1.86 2016/03/02 19:24:20 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[] = "@(#)read.c	8.1 (Berkeley) 6/4/93";
39 #else
40 __RCSID("$NetBSD: read.c,v 1.86 2016/03/02 19:24:20 christos Exp $");
41 #endif
42 #endif /* not lint && not SCCSID */
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 /*
47  * read.c: Clean this junk up! This is horrible code.
48  *	   Terminal read functions
49  */
50 #include <ctype.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <limits.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 
58 #include "el.h"
59 
60 #define OKCMD	-1	/* must be -1! */
61 
62 private int	read__fixio(int, int);
63 private int	read_preread(EditLine *);
64 private int	read_char(EditLine *, wchar_t *);
65 private int	read_getcmd(EditLine *, el_action_t *, Char *);
66 private void	read_pop(c_macro_t *);
67 
68 /* read_init():
69  *	Initialize the read stuff
70  */
71 protected int
read_init(EditLine * el)72 read_init(EditLine *el)
73 {
74 	/* builtin read_char */
75 	el->el_read.read_char = read_char;
76 	return 0;
77 }
78 
79 
80 /* el_read_setfn():
81  *	Set the read char function to the one provided.
82  *	If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
83  */
84 protected int
el_read_setfn(EditLine * el,el_rfunc_t rc)85 el_read_setfn(EditLine *el, el_rfunc_t rc)
86 {
87 	el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
88 	return 0;
89 }
90 
91 
92 /* el_read_getfn():
93  *	return the current read char function, or EL_BUILTIN_GETCFN
94  *	if it is the default one
95  */
96 protected el_rfunc_t
el_read_getfn(EditLine * el)97 el_read_getfn(EditLine *el)
98 {
99        return el->el_read.read_char == read_char ?
100 	    EL_BUILTIN_GETCFN : el->el_read.read_char;
101 }
102 
103 
104 #ifndef MIN
105 #define MIN(A,B) ((A) < (B) ? (A) : (B))
106 #endif
107 
108 #ifdef DEBUG_EDIT
109 private void
read_debug(EditLine * el)110 read_debug(EditLine *el)
111 {
112 
113 	if (el->el_line.cursor > el->el_line.lastchar)
114 		(void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
115 	if (el->el_line.cursor < el->el_line.buffer)
116 		(void) fprintf(el->el_errfile, "cursor < buffer\r\n");
117 	if (el->el_line.cursor > el->el_line.limit)
118 		(void) fprintf(el->el_errfile, "cursor > limit\r\n");
119 	if (el->el_line.lastchar > el->el_line.limit)
120 		(void) fprintf(el->el_errfile, "lastchar > limit\r\n");
121 	if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
122 		(void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
123 }
124 #endif /* DEBUG_EDIT */
125 
126 
127 /* read__fixio():
128  *	Try to recover from a read error
129  */
130 /* ARGSUSED */
131 private int
read__fixio(int fd,int e)132 read__fixio(int fd __attribute__((__unused__)), int e)
133 {
134 
135 	switch (e) {
136 	case -1:		/* Make sure that the code is reachable */
137 
138 #ifdef EWOULDBLOCK
139 	case EWOULDBLOCK:
140 #ifndef TRY_AGAIN
141 #define TRY_AGAIN
142 #endif
143 #endif /* EWOULDBLOCK */
144 
145 #if defined(POSIX) && defined(EAGAIN)
146 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
147 	case EAGAIN:
148 #ifndef TRY_AGAIN
149 #define TRY_AGAIN
150 #endif
151 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
152 #endif /* POSIX && EAGAIN */
153 
154 		e = 0;
155 #ifdef TRY_AGAIN
156 #if defined(F_SETFL) && defined(O_NDELAY)
157 		if ((e = fcntl(fd, F_GETFL, 0)) == -1)
158 			return -1;
159 
160 		if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
161 			return -1;
162 		else
163 			e = 1;
164 #endif /* F_SETFL && O_NDELAY */
165 
166 #ifdef FIONBIO
167 		{
168 			int zero = 0;
169 
170 			if (ioctl(fd, FIONBIO, &zero) == -1)
171 				return -1;
172 			else
173 				e = 1;
174 		}
175 #endif /* FIONBIO */
176 
177 #endif /* TRY_AGAIN */
178 		return e ? 0 : -1;
179 
180 	case EINTR:
181 		return 0;
182 
183 	default:
184 		return -1;
185 	}
186 }
187 
188 
189 /* read_preread():
190  *	Try to read the stuff in the input queue;
191  */
192 private int
read_preread(EditLine * el)193 read_preread(EditLine *el)
194 {
195 	int chrs = 0;
196 
197 	if (el->el_tty.t_mode == ED_IO)
198 		return 0;
199 
200 #ifndef WIDECHAR
201 /* FIONREAD attempts to buffer up multiple bytes, and to make that work
202  * properly with partial wide/UTF-8 characters would need some careful work. */
203 #ifdef FIONREAD
204 	(void) ioctl(el->el_infd, FIONREAD, &chrs);
205 	if (chrs > 0) {
206 		char buf[EL_BUFSIZ];
207 
208 		chrs = read(el->el_infd, buf,
209 		    (size_t) MIN(chrs, EL_BUFSIZ - 1));
210 		if (chrs > 0) {
211 			buf[chrs] = '\0';
212 			el_push(el, buf);
213 		}
214 	}
215 #endif /* FIONREAD */
216 #endif
217 	return chrs > 0;
218 }
219 
220 
221 /* el_push():
222  *	Push a macro
223  */
224 public void
FUN(el,push)225 FUN(el,push)(EditLine *el, const Char *str)
226 {
227 	c_macro_t *ma = &el->el_chared.c_macro;
228 
229 	if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
230 		ma->level++;
231 		if ((ma->macro[ma->level] = Strdup(str)) != NULL)
232 			return;
233 		ma->level--;
234 	}
235 	terminal_beep(el);
236 	terminal__flush(el);
237 }
238 
239 
240 /* read_getcmd():
241  *	Get next command from the input stream, return OKCMD on success.
242  *	Character values > 255 are not looked up in the map, but inserted.
243  */
244 private int
read_getcmd(EditLine * el,el_action_t * cmdnum,Char * ch)245 read_getcmd(EditLine *el, el_action_t *cmdnum, Char *ch)
246 {
247 	static const Char meta = (Char)0x80;
248 	el_action_t cmd;
249 	wchar_t wc;
250 	int num;
251 
252 	el->el_errno = 0;
253 	do {
254 		if ((num = el_wgetc(el, &wc)) != 1) {/* if EOF or error */
255 			el->el_errno = num == 0 ? 0 : errno;
256 			return 0;	/* not OKCMD */
257 		}
258 		*ch = (Char)wc;
259 
260 #ifdef	KANJI
261 		if ((*ch & meta)) {
262 			el->el_state.metanext = 0;
263 			cmd = CcViMap[' '];
264 			break;
265 		} else
266 #endif /* KANJI */
267 
268 		if (el->el_state.metanext) {
269 			el->el_state.metanext = 0;
270 			*ch |= meta;
271 		}
272 #ifdef WIDECHAR
273 		if (*ch >= N_KEYS)
274 			cmd = ED_INSERT;
275 		else
276 #endif
277 			cmd = el->el_map.current[(unsigned char) *ch];
278 		if (cmd == ED_SEQUENCE_LEAD_IN) {
279 			keymacro_value_t val;
280 			switch (keymacro_get(el, ch, &val)) {
281 			case XK_CMD:
282 				cmd = val.cmd;
283 				break;
284 			case XK_STR:
285 				FUN(el,push)(el, val.str);
286 				break;
287 #ifdef notyet
288 			case XK_EXE:
289 				/* XXX: In the future to run a user function */
290 				RunCommand(val.str);
291 				break;
292 #endif
293 			default:
294 				EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
295 				break;
296 			}
297 		}
298 		if (el->el_map.alt == NULL)
299 			el->el_map.current = el->el_map.key;
300 	} while (cmd == ED_SEQUENCE_LEAD_IN);
301 	*cmdnum = cmd;
302 	return OKCMD;
303 }
304 
305 /* read_char():
306  *	Read a character from the tty.
307  */
308 private int
read_char(EditLine * el,wchar_t * cp)309 read_char(EditLine *el, wchar_t *cp)
310 {
311 	ssize_t num_read;
312 	int tried = 0;
313 	char cbuf[MB_LEN_MAX];
314 	size_t cbp = 0;
315 	int save_errno = errno;
316 
317  again:
318 	el->el_signal->sig_no = 0;
319 	while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
320 		int e = errno;
321 		switch (el->el_signal->sig_no) {
322 		case SIGCONT:
323 			FUN(el,set)(el, EL_REFRESH);
324 			/*FALLTHROUGH*/
325 		case SIGWINCH:
326 			sig_set(el);
327 			goto again;
328 		default:
329 			break;
330 		}
331 		if (!tried && read__fixio(el->el_infd, e) == 0) {
332 			errno = save_errno;
333 			tried = 1;
334 		} else {
335 			errno = e;
336 			*cp = L'\0';
337 			return -1;
338 		}
339 	}
340 
341 	/* Test for EOF */
342 	if (num_read == 0) {
343 		*cp = L'\0';
344 		return 0;
345 	}
346 
347 	for (;;) {
348 
349 		++cbp;
350 		switch (ct_mbrtowc(cp, cbuf, cbp)) {
351 		case (size_t)-1:
352 			if (cbp > 1) {
353 				/*
354 				 * Invalid sequence, discard all bytes
355 				 * except the last one.
356 				 */
357 				cbuf[0] = cbuf[cbp - 1];
358 				cbp = 0;
359 				break;
360 			} else {
361 				/* Invalid byte, discard it. */
362 				cbp = 0;
363 				goto again;
364 			}
365 		case (size_t)-2:
366 			if (cbp >= MB_LEN_MAX) {
367 				errno = EILSEQ;
368 				*cp = L'\0';
369 				return -1;
370 			}
371 			/* Incomplete sequence, read another byte. */
372 			goto again;
373 		default:
374 			/* Valid character, process it. */
375 			return 1;
376 		}
377 	}
378 }
379 
380 /* read_pop():
381  *	Pop a macro from the stack
382  */
383 private void
read_pop(c_macro_t * ma)384 read_pop(c_macro_t *ma)
385 {
386 	int i;
387 
388 	el_free(ma->macro[0]);
389 	for (i = 0; i < ma->level; i++)
390 		ma->macro[i] = ma->macro[i + 1];
391 	ma->level--;
392 	ma->offset = 0;
393 }
394 
395 /* el_wgetc():
396  *	Read a wide character
397  */
398 public int
el_wgetc(EditLine * el,wchar_t * cp)399 el_wgetc(EditLine *el, wchar_t *cp)
400 {
401 	int num_read;
402 	c_macro_t *ma = &el->el_chared.c_macro;
403 
404 	terminal__flush(el);
405 	for (;;) {
406 		if (ma->level < 0) {
407 			if (!read_preread(el))
408 				break;
409 		}
410 
411 		if (ma->level < 0)
412 			break;
413 
414 		if (ma->macro[0][ma->offset] == '\0') {
415 			read_pop(ma);
416 			continue;
417 		}
418 
419 		*cp = ma->macro[0][ma->offset++];
420 
421 		if (ma->macro[0][ma->offset] == '\0') {
422 			/* Needed for QuoteMode On */
423 			read_pop(ma);
424 		}
425 
426 		return 1;
427 	}
428 
429 #ifdef DEBUG_READ
430 	(void) fprintf(el->el_errfile, "Turning raw mode on\n");
431 #endif /* DEBUG_READ */
432 	if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
433 		return 0;
434 
435 #ifdef DEBUG_READ
436 	(void) fprintf(el->el_errfile, "Reading a character\n");
437 #endif /* DEBUG_READ */
438 	num_read = (*el->el_read.read_char)(el, cp);
439 	if (num_read < 0)
440 		el->el_errno = errno;
441 #ifdef DEBUG_READ
442 	(void) fprintf(el->el_errfile, "Got it %lc\n", *cp);
443 #endif /* DEBUG_READ */
444 	return num_read;
445 }
446 
447 protected void
read_prepare(EditLine * el)448 read_prepare(EditLine *el)
449 {
450 	if (el->el_flags & HANDLE_SIGNALS)
451 		sig_set(el);
452 	if (el->el_flags & NO_TTY)
453 		return;
454 	if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
455 		tty_rawmode(el);
456 
457 	/* This is relatively cheap, and things go terribly wrong if
458 	   we have the wrong size. */
459 	el_resize(el);
460 	re_clear_display(el);	/* reset the display stuff */
461 	ch_reset(el, 0);
462 	re_refresh(el);		/* print the prompt */
463 
464 	if (el->el_flags & UNBUFFERED)
465 		terminal__flush(el);
466 }
467 
468 protected void
read_finish(EditLine * el)469 read_finish(EditLine *el)
470 {
471 	if ((el->el_flags & UNBUFFERED) == 0)
472 		(void) tty_cookedmode(el);
473 	if (el->el_flags & HANDLE_SIGNALS)
474 		sig_clr(el);
475 }
476 
477 public const Char *
FUN(el,gets)478 FUN(el,gets)(EditLine *el, int *nread)
479 {
480 	int retval;
481 	el_action_t cmdnum = 0;
482 	int num;		/* how many chars we have read at NL */
483 	wchar_t wc;
484 	Char ch, *cp;
485 	int crlf = 0;
486 	int nrb;
487 #ifdef FIONREAD
488 	c_macro_t *ma = &el->el_chared.c_macro;
489 #endif /* FIONREAD */
490 
491 	if (nread == NULL)
492 		nread = &nrb;
493 	*nread = 0;
494 
495 	if (el->el_flags & NO_TTY) {
496 		size_t idx;
497 
498 		cp = el->el_line.buffer;
499 		while ((num = (*el->el_read.read_char)(el, &wc)) == 1) {
500 			*cp = (Char)wc;
501 			/* make sure there is space for next character */
502 			if (cp + 1 >= el->el_line.limit) {
503 				idx = (size_t)(cp - el->el_line.buffer);
504 				if (!ch_enlargebufs(el, (size_t)2))
505 					break;
506 				cp = &el->el_line.buffer[idx];
507 			}
508 			cp++;
509 			if (el->el_flags & UNBUFFERED)
510 				break;
511 			if (cp[-1] == '\r' || cp[-1] == '\n')
512 				break;
513 		}
514 		if (num == -1) {
515 			if (errno == EINTR)
516 				cp = el->el_line.buffer;
517 			el->el_errno = errno;
518 		}
519 
520 		goto noedit;
521 	}
522 
523 
524 #ifdef FIONREAD
525 	if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
526 		long chrs = 0;
527 
528 		(void) ioctl(el->el_infd, FIONREAD, &chrs);
529 		if (chrs == 0) {
530 			if (tty_rawmode(el) < 0) {
531 				errno = 0;
532 				*nread = 0;
533 				return NULL;
534 			}
535 		}
536 	}
537 #endif /* FIONREAD */
538 
539 	if ((el->el_flags & UNBUFFERED) == 0)
540 		read_prepare(el);
541 
542 	if (el->el_flags & EDIT_DISABLED) {
543 		size_t idx;
544 
545 		if ((el->el_flags & UNBUFFERED) == 0)
546 			cp = el->el_line.buffer;
547 		else
548 			cp = el->el_line.lastchar;
549 
550 		terminal__flush(el);
551 
552 		while ((num = (*el->el_read.read_char)(el, &wc)) == 1) {
553 			*cp = (Char)wc;
554 			/* make sure there is space next character */
555 			if (cp + 1 >= el->el_line.limit) {
556 				idx = (size_t)(cp - el->el_line.buffer);
557 				if (!ch_enlargebufs(el, (size_t)2))
558 					break;
559 				cp = &el->el_line.buffer[idx];
560 			}
561 			cp++;
562 			crlf = cp[-1] == '\r' || cp[-1] == '\n';
563 			if (el->el_flags & UNBUFFERED)
564 				break;
565 			if (crlf)
566 				break;
567 		}
568 
569 		if (num == -1) {
570 			if (errno == EINTR)
571 				cp = el->el_line.buffer;
572 			el->el_errno = errno;
573 		}
574 
575 		goto noedit;
576 	}
577 
578 	for (num = OKCMD; num == OKCMD;) {	/* while still editing this
579 						 * line */
580 #ifdef DEBUG_EDIT
581 		read_debug(el);
582 #endif /* DEBUG_EDIT */
583 		/* if EOF or error */
584 		if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
585 			num = -1;
586 #ifdef DEBUG_READ
587 			(void) fprintf(el->el_errfile,
588 			    "Returning from el_gets %d\n", num);
589 #endif /* DEBUG_READ */
590 			break;
591 		}
592 		if (el->el_errno == EINTR) {
593 			el->el_line.buffer[0] = '\0';
594 			el->el_line.lastchar =
595 			    el->el_line.cursor = el->el_line.buffer;
596 			break;
597 		}
598 		if ((size_t)cmdnum >= el->el_map.nfunc) {	/* BUG CHECK command */
599 #ifdef DEBUG_EDIT
600 			(void) fprintf(el->el_errfile,
601 			    "ERROR: illegal command from key 0%o\r\n", ch);
602 #endif /* DEBUG_EDIT */
603 			continue;	/* try again */
604 		}
605 		/* now do the real command */
606 #ifdef DEBUG_READ
607 		{
608 			el_bindings_t *b;
609 			for (b = el->el_map.help; b->name; b++)
610 				if (b->func == cmdnum)
611 					break;
612 			if (b->name)
613 				(void) fprintf(el->el_errfile,
614 				    "Executing " FSTR "\n", b->name);
615 			else
616 				(void) fprintf(el->el_errfile,
617 				    "Error command = %d\n", cmdnum);
618 		}
619 #endif /* DEBUG_READ */
620 		/* vi redo needs these way down the levels... */
621 		el->el_state.thiscmd = cmdnum;
622 		el->el_state.thisch = ch;
623 		if (el->el_map.type == MAP_VI &&
624 		    el->el_map.current == el->el_map.key &&
625 		    el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
626 			if (cmdnum == VI_DELETE_PREV_CHAR &&
627 			    el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
628 			    && Isprint(el->el_chared.c_redo.pos[-1]))
629 				el->el_chared.c_redo.pos--;
630 			else
631 				*el->el_chared.c_redo.pos++ = ch;
632 		}
633 		retval = (*el->el_map.func[cmdnum]) (el, ch);
634 #ifdef DEBUG_READ
635 		(void) fprintf(el->el_errfile,
636 			"Returned state %d\n", retval );
637 #endif /* DEBUG_READ */
638 
639 		/* save the last command here */
640 		el->el_state.lastcmd = cmdnum;
641 
642 		/* use any return value */
643 		switch (retval) {
644 		case CC_CURSOR:
645 			re_refresh_cursor(el);
646 			break;
647 
648 		case CC_REDISPLAY:
649 			re_clear_lines(el);
650 			re_clear_display(el);
651 			/* FALLTHROUGH */
652 
653 		case CC_REFRESH:
654 			re_refresh(el);
655 			break;
656 
657 		case CC_REFRESH_BEEP:
658 			re_refresh(el);
659 			terminal_beep(el);
660 			break;
661 
662 		case CC_NORM:	/* normal char */
663 			break;
664 
665 		case CC_ARGHACK:	/* Suggested by Rich Salz */
666 			/* <[email protected]> */
667 			continue;	/* keep going... */
668 
669 		case CC_EOF:	/* end of file typed */
670 			if ((el->el_flags & UNBUFFERED) == 0)
671 				num = 0;
672 			else if (num == -1) {
673 				*el->el_line.lastchar++ = CONTROL('d');
674 				el->el_line.cursor = el->el_line.lastchar;
675 				num = 1;
676 			}
677 			break;
678 
679 		case CC_NEWLINE:	/* normal end of line */
680 			num = (int)(el->el_line.lastchar - el->el_line.buffer);
681 			break;
682 
683 		case CC_FATAL:	/* fatal error, reset to known state */
684 #ifdef DEBUG_READ
685 			(void) fprintf(el->el_errfile,
686 			    "*** editor fatal ERROR ***\r\n\n");
687 #endif /* DEBUG_READ */
688 			/* put (real) cursor in a known place */
689 			re_clear_display(el);	/* reset the display stuff */
690 			ch_reset(el, 1);	/* reset the input pointers */
691 			re_refresh(el); /* print the prompt again */
692 			break;
693 
694 		case CC_ERROR:
695 		default:	/* functions we don't know about */
696 #ifdef DEBUG_READ
697 			(void) fprintf(el->el_errfile,
698 			    "*** editor ERROR ***\r\n\n");
699 #endif /* DEBUG_READ */
700 			terminal_beep(el);
701 			terminal__flush(el);
702 			break;
703 		}
704 		el->el_state.argument = 1;
705 		el->el_state.doingarg = 0;
706 		el->el_chared.c_vcmd.action = NOP;
707 		if (el->el_flags & UNBUFFERED)
708 			break;
709 	}
710 
711 	terminal__flush(el);		/* flush any buffered output */
712 	/* make sure the tty is set up correctly */
713 	if ((el->el_flags & UNBUFFERED) == 0) {
714 		read_finish(el);
715 		*nread = num != -1 ? num : 0;
716 	} else {
717 		*nread = (int)(el->el_line.lastchar - el->el_line.buffer);
718 	}
719 	goto done;
720 noedit:
721 	el->el_line.cursor = el->el_line.lastchar = cp;
722 	*cp = '\0';
723 	*nread = (int)(el->el_line.cursor - el->el_line.buffer);
724 done:
725 	if (*nread == 0) {
726 		if (num == -1) {
727 			*nread = -1;
728 			errno = el->el_errno;
729 		}
730 		return NULL;
731 	} else
732 		return el->el_line.buffer;
733 }
734