xref: /netbsd-src/lib/libcurses/get_wch.c (revision 53d1339bf7f9c7367b35a9e1ebe693f9b047a47b)
1 /*   $NetBSD: get_wch.c,v 1.24 2020/07/06 23:33:38 uwe Exp $ */
2 
3 /*
4  * Copyright (c) 2005 The NetBSD Foundation Inc.
5  * All rights reserved.
6  *
7  * This code is derived from code donated to the NetBSD Foundation
8  * by Ruibiao Qiu <ruibiao@arl.wustl.edu,ruibiao@gmail.com>.
9  *
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *	notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *	notice, this list of conditions and the following disclaimer in the
18  *	documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the NetBSD Foundation nor the names of its
20  *	contributors may be used to endorse or promote products derived
21  *	from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND
24  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
25  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 #ifndef lint
39 __RCSID("$NetBSD: get_wch.c,v 1.24 2020/07/06 23:33:38 uwe Exp $");
40 #endif						  /* not lint */
41 
42 #include <errno.h>
43 #include <string.h>
44 #include <stdlib.h>
45 #include <unistd.h>
46 #include <stdio.h>
47 #include "curses.h"
48 #include "curses_private.h"
49 #include "keymap.h"
50 
51 static short wstate;		/* state of the wcinkey function */
52 extern short _cursesi_state;	/* storage declared in getch.c */
53 
54 /* prototypes for private functions */
55 static int inkey(wchar_t *wc, int to, int delay);
56 static wint_t __fgetwc_resize(FILE *infd, bool *resized);
57 
58 /*
59  * __init_get_wch - initialise all the pointers & structures needed to make
60  * get_wch work in keypad mode.
61  *
62  */
63 void
64 __init_get_wch(SCREEN *screen)
65 {
66 	wstate = INKEY_NORM;
67 	memset(&screen->cbuf, 0, sizeof(screen->cbuf));
68 	screen->cbuf_head = screen->cbuf_tail = screen->cbuf_cur = 0;
69 }
70 
71 
72 /*
73  * inkey - do the work to process keyboard input, check for multi-key
74  * sequences and return the appropriate symbol if we get a match.
75  *
76  */
77 static int
78 inkey(wchar_t *wc, int to, int delay)
79 {
80 	wchar_t		 k = 0;
81 	int		 c, mapping, ret = 0;
82 	size_t	  mlen = 0;
83 	keymap_t	*current = _cursesi_screen->base_keymap;
84 	FILE		*infd = _cursesi_screen->infd;
85 	int		 *start = &_cursesi_screen->cbuf_head,
86 				*working = &_cursesi_screen->cbuf_cur,
87 				*end = &_cursesi_screen->cbuf_tail;
88 	char		*inbuf = &_cursesi_screen->cbuf[ 0 ];
89 
90 #ifdef DEBUG
91 	__CTRACE(__CTRACE_INPUT, "inkey (%p, %d, %d)\n", wc, to, delay);
92 #endif
93 	for (;;) { /* loop until we get a complete key sequence */
94 		if (wstate == INKEY_NORM) {
95 			if (delay && __timeout(delay) == ERR)
96 				return ERR;
97 			c = __fgetc_resize(infd);
98 			if (c == ERR || c == KEY_RESIZE) {
99 				clearerr(infd);
100 				return c;
101 			}
102 
103 			if (delay && (__notimeout() == ERR))
104 				return ERR;
105 
106 			k = (wchar_t)c;
107 #ifdef DEBUG
108 			__CTRACE(__CTRACE_INPUT,
109 			    "inkey (wstate normal) got '%s'\n", unctrl(k));
110 #endif
111 
112 			inbuf[*end] = k;
113 			*end = (*end + 1) % MAX_CBUF_SIZE;
114 			*working = *start;
115 			wstate = INKEY_ASSEMBLING; /* go to assembling state */
116 #ifdef DEBUG
117 			__CTRACE(__CTRACE_INPUT,
118 			    "inkey: NORM=>ASSEMBLING: start(%d), "
119 			    "current(%d), end(%d)\n", *start, *working, *end);
120 #endif /* DEBUG */
121 		} else if (wstate == INKEY_BACKOUT) {
122 			k = inbuf[*working];
123 			*working = (*working + 1) % MAX_CBUF_SIZE;
124 			if (*working == *end) {	/* see if run out of keys */
125 				/* if so, switch to assembling */
126 				wstate = INKEY_ASSEMBLING;
127 #ifdef DEBUG
128 				__CTRACE(__CTRACE_INPUT,
129 				    "inkey: BACKOUT=>ASSEMBLING, start(%d), "
130 				    "current(%d), end(%d)\n",
131 				    *start, *working, *end);
132 #endif /* DEBUG */
133 			}
134 		} else if (wstate == INKEY_ASSEMBLING) {
135 			/* assembling a key sequence */
136 			if (delay) {
137 				if (__timeout(to ? (ESCDELAY / 100) : delay)
138 						== ERR)
139 					return ERR;
140 			} else {
141 				if (to && (__timeout(ESCDELAY / 100) == ERR))
142 					return ERR;
143 			}
144 
145 			c = __fgetc_resize(infd);
146 			if (ferror(infd)) {
147 				clearerr(infd);
148 				return c;
149 			}
150 
151 			if ((to || delay) && (__notimeout() == ERR))
152 				return ERR;
153 
154 			k = (wchar_t)c;
155 #ifdef DEBUG
156 			__CTRACE(__CTRACE_INPUT,
157 			    "inkey (wstate assembling) got '%s'\n", unctrl(k));
158 #endif /* DEBUG */
159 			if (feof(infd)) { /* inter-char T/O, start backout */
160 				clearerr(infd);
161 				if (*start == *end)
162 					/* no chars in the buffer, restart */
163 					continue;
164 
165 				k = inbuf[*start];
166 				wstate = INKEY_TIMEOUT;
167 #ifdef DEBUG
168 				__CTRACE(__CTRACE_INPUT,
169 				    "inkey: ASSEMBLING=>TIMEOUT, start(%d), "
170 				    "current(%d), end(%d)\n",
171 				    *start, *working, *end);
172 #endif /* DEBUG */
173 			} else {
174 				inbuf[*end] = k;
175 				*working = *end;
176 				*end = (*end + 1) % MAX_CBUF_SIZE;
177 #ifdef DEBUG
178 				__CTRACE(__CTRACE_INPUT,
179 				    "inkey: ASSEMBLING: start(%d), "
180 				    "current(%d), end(%d)",
181 				    *start, *working, *end);
182 #endif /* DEBUG */
183 			}
184 		} else if (wstate == INKEY_WCASSEMBLING) {
185 			/* assembling a wide-char sequence */
186 			if (delay) {
187 				if (__timeout(to ? (ESCDELAY / 100) : delay)
188 						== ERR)
189 					return ERR;
190 			} else {
191 				if (to && (__timeout(ESCDELAY / 100) == ERR))
192 					return ERR;
193 			}
194 
195 			c = __fgetc_resize(infd);
196 			if (ferror(infd)) {
197 				clearerr(infd);
198 				return c;
199 			}
200 
201 			if ((to || delay) && (__notimeout() == ERR))
202 				return ERR;
203 
204 			k = (wchar_t)c;
205 #ifdef DEBUG
206 			__CTRACE(__CTRACE_INPUT,
207 			    "inkey (wstate wcassembling) got '%s'\n",
208 				unctrl(k));
209 #endif
210 			if (feof(infd)) { /* inter-char T/O, start backout */
211 				clearerr(infd);
212 				if (*start == *end)
213 					/* no chars in the buffer, restart */
214 					continue;
215 
216 				*wc = inbuf[*start];
217 				*working = *start = (*start +1) % MAX_CBUF_SIZE;
218 				if (*start == *end) {
219 					_cursesi_state = wstate = INKEY_NORM;
220 #ifdef DEBUG
221 					__CTRACE(__CTRACE_INPUT,
222 					    "inkey: WCASSEMBLING=>NORM, "
223 					    "start(%d), current(%d), end(%d)",
224 					    *start, *working, *end);
225 #endif /* DEBUG */
226 				} else {
227 					_cursesi_state = wstate = INKEY_BACKOUT;
228 #ifdef DEBUG
229 					__CTRACE(__CTRACE_INPUT,
230 					    "inkey: WCASSEMBLING=>BACKOUT, "
231 					    "start(%d), current(%d), end(%d)",
232 					    *start, *working, *end);
233 #endif /* DEBUG */
234 				}
235 				return OK;
236 			} else {
237 				/* assembling wide characters */
238 				inbuf[*end] = k;
239 				*working = *end;
240 				*end = (*end + 1) % MAX_CBUF_SIZE;
241 #ifdef DEBUG
242 				__CTRACE(__CTRACE_INPUT,
243 				    "inkey: WCASSEMBLING[head(%d), "
244 				    "urrent(%d), tail(%d)]\n",
245 				    *start, *working, *end);
246 #endif /* DEBUG */
247 				ret = (int)mbrtowc(wc, inbuf + (*working), 1,
248 						   &_cursesi_screen->sp);
249 #ifdef DEBUG
250 				__CTRACE(__CTRACE_INPUT,
251 				    "inkey: mbrtowc returns %d, wc(%x)\n",
252 				    ret, *wc);
253 #endif /* DEBUG */
254 				if (ret == -2) {
255 					*working = (*working+1) % MAX_CBUF_SIZE;
256 					continue;
257 				}
258 				if ( ret == 0 )
259 					ret = 1;
260 				if ( ret == -1 ) {
261 					/* return the 1st character we know */
262 					*wc = inbuf[*start];
263 					*working = *start = (*start + 1) % MAX_CBUF_SIZE;
264 #ifdef DEBUG
265 					__CTRACE(__CTRACE_INPUT,
266 					    "inkey: Invalid wide char(%x) "
267 					    "[head(%d), current(%d), "
268 					    "tail(%d)]\n",
269 					    *wc, *start, *working, *end);
270 #endif /* DEBUG */
271 				} else { /* > 0 */
272 					/* return the wide character */
273 					*start = *working
274 					       = (*working + ret)%MAX_CBUF_SIZE;
275 #ifdef DEBUG
276 					__CTRACE(__CTRACE_INPUT,
277 					    "inkey: Wide char found(%x) "
278 					    "[head(%d), current(%d), "
279 					    "tail(%d)]\n",
280 					    *wc, *start, *working, *end);
281 #endif /* DEBUG */
282 				}
283 
284 				if (*start == *end) {
285 					/* only one char processed */
286 					_cursesi_state = wstate = INKEY_NORM;
287 #ifdef DEBUG
288 					__CTRACE(__CTRACE_INPUT,
289 					    "inkey: WCASSEMBLING=>NORM, "
290 					    "start(%d), current(%d), end(%d)",
291 					    *start, *working, *end);
292 #endif /* DEBUG */
293 				} else {
294 					/* otherwise we must have more than
295 					 * one char to backout */
296 					_cursesi_state = wstate = INKEY_BACKOUT;
297 #ifdef DEBUG
298 					__CTRACE(__CTRACE_INPUT,
299 					    "inkey: WCASSEMBLING=>BACKOUT, "
300 					    "start(%d), current(%d), end(%d)",
301 					    *start, *working, *end);
302 #endif /* DEBUG */
303 				}
304 				return OK;
305 			}
306 		} else {
307 			fprintf(stderr, "Inkey wstate screwed - exiting!!!");
308 			exit(2);
309 		}
310 
311 		/*
312 		 * Check key has no special meaning and we have not
313 		 * timed out and the key has not been disabled
314 		 */
315 		mapping = current->mapping[k];
316 		if (((wstate == INKEY_TIMEOUT) || (mapping < 0))
317 				|| ((current->key[mapping]->type
318 					== KEYMAP_LEAF)
319 				&& (current->key[mapping]->enable == FALSE)))
320 		{
321 			/* wide-character specific code */
322 #ifdef DEBUG
323 			__CTRACE(__CTRACE_INPUT,
324 			    "inkey: Checking for wide char\n");
325 #endif /* DEBUG */
326 			mbrtowc( NULL, NULL, 1, &_cursesi_screen->sp );
327 			*working = *start;
328 			mlen = *end > *working ?
329 				*end - *working : MAX_CBUF_SIZE - *working;
330 			if (!mlen)
331 				return ERR;
332 #ifdef DEBUG
333 			__CTRACE(__CTRACE_INPUT,
334 			    "inkey: Check wide char[head(%d), "
335 			    "current(%d), tail(%d), mlen(%ld)]\n",
336 			    *start, *working, *end, (long) mlen);
337 #endif /* DEBUG */
338 			ret = (int)mbrtowc(wc, inbuf + (*working), mlen,
339 			                   &_cursesi_screen->sp);
340 #ifdef DEBUG
341 			__CTRACE(__CTRACE_INPUT,
342 			    "inkey: mbrtowc returns %d, wc(%x)\n", ret, *wc);
343 #endif /* DEBUG */
344 			if (ret == -2 && *end < *working) {
345 				/* second half of a wide character */
346 				*working = 0;
347 				mlen = *end;
348 				if (mlen)
349 					ret = (int)mbrtowc(wc, inbuf, mlen,
350 							  &_cursesi_screen->sp);
351 			}
352 			if (ret == -2 && wstate != INKEY_TIMEOUT) {
353 				*working = (*working + (int) mlen)
354 					% MAX_CBUF_SIZE;
355 				wstate = INKEY_WCASSEMBLING;
356 				continue;
357 			}
358 			if (ret == 0)
359 				ret = 1;
360 			if (ret == -1) {
361 				/* return the first key we know about */
362 				*wc = inbuf[*start];
363 				*working = *start
364 					= (*start + 1) % MAX_CBUF_SIZE;
365 #ifdef DEBUG
366 				__CTRACE(__CTRACE_INPUT,
367 				    "inkey: Invalid wide char(%x)[head(%d), "
368 				    "current(%d), tail(%d)]\n",
369 				    *wc, *start, *working, *end);
370 #endif /* DEBUG */
371 			} else { /* > 0 */
372 				/* return the wide character */
373 				*start = *working
374 					= (*working + ret) % MAX_CBUF_SIZE;
375 #ifdef DEBUG
376 				__CTRACE(__CTRACE_INPUT,
377 				    "inkey: Wide char found(%x)[head(%d), "
378 				    "current(%d), tail(%d)]\n",
379 				    *wc, *start, *working, *end);
380 #endif /* DEBUG */
381 			}
382 
383 			if (*start == *end) {	/* only one char processed */
384 				_cursesi_state = wstate = INKEY_NORM;
385 #ifdef DEBUG
386 				__CTRACE(__CTRACE_INPUT,
387 				    "inkey: Empty cbuf=>NORM, "
388 				    "start(%d), current(%d), end(%d)\n",
389 				    *start, *working, *end);
390 #endif /* DEBUG */
391 			} else {
392 				/* otherwise we must have more than one
393 				 * char to backout */
394 				_cursesi_state = wstate = INKEY_BACKOUT;
395 #ifdef DEBUG
396 				__CTRACE(__CTRACE_INPUT,
397 				    "inkey: Non-empty cbuf=>BACKOUT, "
398 				    "start(%d), current(%d), end(%d)\n",
399 				    *start, *working, *end);
400 #endif /* DEBUG */
401 			}
402 			return OK;
403 		} else {	/* must be part of a multikey sequence */
404 					/* check for completed key sequence */
405 			if (current->key[current->mapping[k]]->type
406 					== KEYMAP_LEAF) {
407 				/* eat the key sequence in cbuf */
408 				*start = *working = ( *working + 1 )
409 				    % MAX_CBUF_SIZE;
410 
411 				/* check if inbuf empty now */
412 #ifdef DEBUG
413 				__CTRACE(__CTRACE_INPUT,
414 				    "inkey: Key found(%s)\n",
415 				    key_name(current->key[mapping]->value.symbol));
416 #endif /* DEBUG */
417 				if (*start == *end) {
418 					/* if it is go back to normal */
419 					_cursesi_state = wstate = INKEY_NORM;
420 #ifdef DEBUG
421 					__CTRACE(__CTRACE_INPUT,
422 					    "[inkey]=>NORM, start(%d), "
423 					    "current(%d), end(%d)",
424 					    *start, *working, *end);
425 #endif /* DEBUG */
426 				} else {
427 					/* otherwise go to backout state */
428 					_cursesi_state = wstate = INKEY_BACKOUT;
429 #ifdef DEBUG
430 					__CTRACE(__CTRACE_INPUT,
431 					    "[inkey]=>BACKOUT, start(%d), "
432 					    "current(%d), end(%d)",
433 					    *start, *working, *end );
434 #endif /* DEBUG */
435 				}
436 
437 				/* return the symbol */
438 				*wc = current->key[mapping]->value.symbol;
439 				return KEY_CODE_YES;
440 			} else {
441 				/* Step to next part of multi-key sequence */
442 				current = current->key[current->mapping[k]]->value.next;
443 			}
444 		}
445 	}
446 }
447 
448 /*
449  * get_wch --
450  *	Read in a wide character from stdscr.
451  */
452 int
453 get_wch(wint_t *ch)
454 {
455 	return wget_wch(stdscr, ch);
456 }
457 
458 /*
459  * mvget_wch --
460  *	  Read in a character from stdscr at the given location.
461  */
462 int
463 mvget_wch(int y, int x, wint_t *ch)
464 {
465 	return mvwget_wch(stdscr, y, x, ch);
466 }
467 
468 /*
469  * mvwget_wch --
470  *	  Read in a character from stdscr at the given location in the
471  *	  given window.
472  */
473 int
474 mvwget_wch(WINDOW *win, int y, int x, wint_t *ch)
475 {
476 	if (wmove(win, y, x) == ERR)
477 		return ERR;
478 
479 	return wget_wch(win, ch);
480 }
481 
482 /*
483  * wget_wch --
484  *	Read in a wide character from the window.
485  */
486 int
487 wget_wch(WINDOW *win, wint_t *ch)
488 {
489 	int ret, weset;
490 	int c;
491 	FILE *infd = _cursesi_screen->infd;
492 	cchar_t wc;
493 	wchar_t inp, ws[2];
494 
495 	if (!(win->flags & __SCROLLOK)
496 	    && (win->flags & __FULLWIN)
497 	    && win->curx == win->maxx - 1
498 	    && win->cury == win->maxy - 1
499 	    && __echoit)
500 		return ERR;
501 
502 	if (!(win->flags & __ISPAD) && is_wintouched(win))
503 		wrefresh(win);
504 #ifdef DEBUG
505 	__CTRACE(__CTRACE_INPUT, "wget_wch: __echoit = %d, "
506 	    "__rawmode = %d, __nl = %d, flags = %#.4x\n",
507 	    __echoit, __rawmode, _cursesi_screen->nl, win->flags);
508 #endif
509 	if (_cursesi_screen->resized) {
510 		resizeterm(LINES, COLS);
511 		_cursesi_screen->resized = 0;
512 		*ch = KEY_RESIZE;
513 		return KEY_CODE_YES;
514 	}
515 	if (_cursesi_screen->unget_pos) {
516 #ifdef DEBUG
517 		__CTRACE(__CTRACE_INPUT, "wget_wch returning char at %d\n",
518 		    _cursesi_screen->unget_pos);
519 #endif
520 		_cursesi_screen->unget_pos--;
521 		*ch = _cursesi_screen->unget_list[_cursesi_screen->unget_pos];
522 		if (__echoit) {
523 			ws[0] = *ch, ws[1] = L'\0';
524 			setcchar(&wc, ws, win->wattr, 0, NULL);
525 			wadd_wch(win, &wc);
526 		}
527 		return KEY_CODE_YES;
528 	}
529 	if (__echoit && !__rawmode) {
530 		cbreak();
531 		weset = 1;
532 	} else
533 		weset = 0;
534 
535 	__save_termios();
536 
537 	if (win->flags & __KEYPAD) {
538 		switch (win->delay) {
539 			case -1:
540 				ret = inkey(&inp,
541 					win->flags & __NOTIMEOUT ? 0 : 1, 0);
542 				break;
543 			case 0:
544 				if (__nodelay() == ERR)
545 					return ERR;
546 				ret = inkey(&inp, 0, 0);
547 				break;
548 			default:
549 				ret = inkey(&inp,
550 					win->flags & __NOTIMEOUT ? 0 : 1,
551 					win->delay);
552 				break;
553 		}
554 		if ( ret == ERR )
555 			return ERR;
556 	} else {
557 		bool resized;
558 
559 		switch (win->delay) {
560 			case -1:
561 				break;
562 			case 0:
563 				if (__nodelay() == ERR)
564 					return ERR;
565 				break;
566 			default:
567 				if (__timeout(win->delay) == ERR)
568 					return ERR;
569 				break;
570 		}
571 
572 		c = __fgetwc_resize(infd, &resized);
573 		if (c == WEOF) {
574 			clearerr(infd);
575 			__restore_termios();
576 			if (resized) {
577 				*ch = KEY_RESIZE;
578 				return KEY_CODE_YES;
579 			} else
580 				return ERR;
581 		} else {
582 			ret = c;
583 			inp = c;
584 		}
585 	}
586 #ifdef DEBUG
587 	if (inp > 255)
588 		/* we have a key symbol - treat it differently */
589 		/* XXXX perhaps __unctrl should be expanded to include
590 		 * XXXX the keysyms in the table....
591 		 */
592 		__CTRACE(__CTRACE_INPUT, "wget_wch assembled keysym 0x%x\n",
593 		    inp);
594 	else
595 		__CTRACE(__CTRACE_INPUT, "wget_wch got '%s'\n", unctrl(inp));
596 #endif
597 	if (win->delay > -1) {
598 		if (__delay() == ERR)
599 			return ERR;
600 	}
601 
602 	__restore_termios();
603 
604 	if (__echoit) {
605 		if ( ret == KEY_CODE_YES ) {
606 			/* handle [DEL], [BS], and [LEFT] */
607 			if ( win->curx &&
608 					( inp == KEY_DC ||
609 					  inp == KEY_BACKSPACE ||
610 					  inp == KEY_LEFT )) {
611 				wmove( win, win->cury, win->curx - 1);
612 				wdelch( win );
613 			}
614 		} else {
615 			ws[ 0 ] = inp, ws[ 1 ] = L'\0';
616 			setcchar( &wc, ws, win->wattr, 0, NULL );
617 			wadd_wch( win, &wc );
618 		}
619 	}
620 
621 	if (weset)
622 		nocbreak();
623 
624 	if (_cursesi_screen->nl && inp == 13)
625 		inp = 10;
626 
627 	*ch = inp;
628 
629 	if ( ret == KEY_CODE_YES )
630 		return KEY_CODE_YES;
631 	return inp < 0 ? ERR : OK;
632 }
633 
634 /*
635  * unget_wch --
636  *	 Put the wide character back into the input queue.
637  */
638 int
639 unget_wch(const wchar_t c)
640 {
641 	return __unget((wint_t)c);
642 }
643 
644 /*
645  * __fgetwc_resize --
646  *    Any call to fgetwc(3) should use this function instead.
647  */
648 static wint_t
649 __fgetwc_resize(FILE *infd, bool *resized)
650 {
651 	wint_t c;
652 
653 	c = fgetwc(infd);
654 	if (c != WEOF)
655 		return c;
656 
657 	if (!ferror(infd) || errno != EINTR || !_cursesi_screen->resized)
658 		return ERR;
659 #ifdef DEBUG
660 	__CTRACE(__CTRACE_INPUT, "__fgetwc_resize returning KEY_RESIZE\n");
661 #endif
662 	resizeterm(LINES, COLS);
663 	_cursesi_screen->resized = 0;
664 	*resized = true;
665 	return c;
666 }
667