xref: /trueos/lib/libedit/read.c (revision f3fa4bdf8b98edb697d801e65b8b2bd542f15787)
1 /*-
2  * Copyright (c) 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Christos Zoulas of Cornell University.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	$NetBSD: read.c,v 1.52 2009/07/22 15:57:00 christos Exp $
33  */
34 
35 #if !defined(lint) && !defined(SCCSID)
36 static char sccsid[] = "@(#)read.c	8.1 (Berkeley) 6/4/93";
37 #endif /* not lint && not SCCSID */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 /*
42  * read.c: Clean this junk up! This is horrible code.
43  *	   Terminal read functions
44  */
45 #include "sys.h"
46 #include <errno.h>
47 #include <fcntl.h>
48 #include <unistd.h>
49 #include <stdlib.h>
50 #include "el.h"
51 
52 #define	OKCMD	-1
53 
54 private int	read__fixio(int, int);
55 private int	read_preread(EditLine *);
56 private int	read_char(EditLine *, char *);
57 private int	read_getcmd(EditLine *, el_action_t *, char *);
58 private void	read_pop(c_macro_t *);
59 
60 /* read_init():
61  *	Initialize the read stuff
62  */
63 protected int
read_init(EditLine * el)64 read_init(EditLine *el)
65 {
66 	/* builtin read_char */
67 	el->el_read.read_char = read_char;
68 	return 0;
69 }
70 
71 
72 /* el_read_setfn():
73  *	Set the read char function to the one provided.
74  *	If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
75  */
76 protected int
el_read_setfn(EditLine * el,el_rfunc_t rc)77 el_read_setfn(EditLine *el, el_rfunc_t rc)
78 {
79 	el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
80 	return 0;
81 }
82 
83 
84 /* el_read_getfn():
85  *	return the current read char function, or EL_BUILTIN_GETCFN
86  *	if it is the default one
87  */
88 protected el_rfunc_t
el_read_getfn(EditLine * el)89 el_read_getfn(EditLine *el)
90 {
91        return (el->el_read.read_char == read_char) ?
92 	    EL_BUILTIN_GETCFN : el->el_read.read_char;
93 }
94 
95 
96 #ifndef MIN
97 #define MIN(A,B) ((A) < (B) ? (A) : (B))
98 #endif
99 
100 #ifdef DEBUG_EDIT
101 private void
read_debug(EditLine * el)102 read_debug(EditLine *el)
103 {
104 
105 	if (el->el_line.cursor > el->el_line.lastchar)
106 		(void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
107 	if (el->el_line.cursor < el->el_line.buffer)
108 		(void) fprintf(el->el_errfile, "cursor < buffer\r\n");
109 	if (el->el_line.cursor > el->el_line.limit)
110 		(void) fprintf(el->el_errfile, "cursor > limit\r\n");
111 	if (el->el_line.lastchar > el->el_line.limit)
112 		(void) fprintf(el->el_errfile, "lastchar > limit\r\n");
113 	if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
114 		(void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
115 }
116 #endif /* DEBUG_EDIT */
117 
118 
119 /* read__fixio():
120  *	Try to recover from a read error
121  */
122 /* ARGSUSED */
123 private int
read__fixio(int fd __unused,int e)124 read__fixio(int fd __unused, int e)
125 {
126 
127 	switch (e) {
128 	case -1:		/* Make sure that the code is reachable */
129 
130 #ifdef EWOULDBLOCK
131 	case EWOULDBLOCK:
132 #ifndef TRY_AGAIN
133 #define	TRY_AGAIN
134 #endif
135 #endif /* EWOULDBLOCK */
136 
137 #if defined(POSIX) && defined(EAGAIN)
138 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
139 	case EAGAIN:
140 #ifndef TRY_AGAIN
141 #define	TRY_AGAIN
142 #endif
143 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
144 #endif /* POSIX && EAGAIN */
145 
146 		e = 0;
147 #ifdef TRY_AGAIN
148 #if defined(F_SETFL) && defined(O_NDELAY)
149 		if ((e = fcntl(fd, F_GETFL, 0)) == -1)
150 			return (-1);
151 
152 		if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
153 			return (-1);
154 		else
155 			e = 1;
156 #endif /* F_SETFL && O_NDELAY */
157 
158 #ifdef FIONBIO
159 		{
160 			int zero = 0;
161 
162 			if (ioctl(fd, FIONBIO, (ioctl_t) & zero) == -1)
163 				return (-1);
164 			else
165 				e = 1;
166 		}
167 #endif /* FIONBIO */
168 
169 #endif /* TRY_AGAIN */
170 		return (e ? 0 : -1);
171 
172 	case EINTR:
173 		return (0);
174 
175 	default:
176 		return (-1);
177 	}
178 }
179 
180 
181 /* read_preread():
182  *	Try to read the stuff in the input queue;
183  */
184 private int
read_preread(EditLine * el)185 read_preread(EditLine *el)
186 {
187 	int chrs = 0;
188 
189 	if (el->el_tty.t_mode == ED_IO)
190 		return (0);
191 
192 #ifdef FIONREAD
193 	(void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
194 	if (chrs > 0) {
195 		char buf[EL_BUFSIZ];
196 
197 		chrs = read(el->el_infd, buf,
198 		    (size_t) MIN(chrs, EL_BUFSIZ - 1));
199 		if (chrs > 0) {
200 			buf[chrs] = '\0';
201 			el_push(el, buf);
202 		}
203 	}
204 #endif /* FIONREAD */
205 
206 	return (chrs > 0);
207 }
208 
209 
210 /* el_push():
211  *	Push a macro
212  */
213 public void
el_push(EditLine * el,const char * str)214 el_push(EditLine *el, const char *str)
215 {
216 	c_macro_t *ma = &el->el_chared.c_macro;
217 
218 	if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
219 		ma->level++;
220 		if ((ma->macro[ma->level] = el_strdup(str)) != NULL)
221 			return;
222 		ma->level--;
223 	}
224 	term_beep(el);
225 	term__flush(el);
226 }
227 
228 
229 /* read_getcmd():
230  *	Return next command from the input stream.
231  */
232 private int
read_getcmd(EditLine * el,el_action_t * cmdnum,char * ch)233 read_getcmd(EditLine *el, el_action_t *cmdnum, char *ch)
234 {
235 	el_action_t cmd;
236 	int num;
237 
238 	el->el_errno = 0;
239 	do {
240 		if ((num = el_getc(el, ch)) != 1) {	/* if EOF or error */
241 			el->el_errno = num == 0 ? 0 : errno;
242 			return (num);
243 		}
244 
245 #ifdef	KANJI
246 		if ((*ch & 0200)) {
247 			el->el_state.metanext = 0;
248 			cmd = CcViMap[' '];
249 			break;
250 		} else
251 #endif /* KANJI */
252 
253 		if (el->el_state.metanext) {
254 			el->el_state.metanext = 0;
255 			*ch |= 0200;
256 		}
257 		cmd = el->el_map.current[(unsigned char) *ch];
258 		if (cmd == ED_SEQUENCE_LEAD_IN) {
259 			key_value_t val;
260 			switch (key_get(el, ch, &val)) {
261 			case XK_CMD:
262 				cmd = val.cmd;
263 				break;
264 			case XK_STR:
265 				el_push(el, val.str);
266 				break;
267 #ifdef notyet
268 			case XK_EXE:
269 				/* XXX: In the future to run a user function */
270 				RunCommand(val.str);
271 				break;
272 #endif
273 			default:
274 				EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
275 				break;
276 			}
277 		}
278 		if (el->el_map.alt == NULL)
279 			el->el_map.current = el->el_map.key;
280 	} while (cmd == ED_SEQUENCE_LEAD_IN);
281 	*cmdnum = cmd;
282 	return (OKCMD);
283 }
284 
285 
286 /* read_char():
287  *	Read a character from the tty.
288  */
289 private int
read_char(EditLine * el,char * cp)290 read_char(EditLine *el, char *cp)
291 {
292 	ssize_t num_read;
293 	int tried = 0;
294 
295  again:
296 	el->el_signal->sig_no = 0;
297 	while ((num_read = read(el->el_infd, cp, 1)) == -1) {
298 		if (el->el_signal->sig_no == SIGCONT) {
299 			sig_set(el);
300 			el_set(el, EL_REFRESH);
301 			goto again;
302 		}
303 		if (!tried && read__fixio(el->el_infd, errno) == 0)
304 			tried = 1;
305 		else {
306 			*cp = '\0';
307 			return (-1);
308 		}
309 	}
310 	return (int)num_read;
311 }
312 
313 /* read_pop():
314  *	Pop a macro from the stack
315  */
316 private void
read_pop(c_macro_t * ma)317 read_pop(c_macro_t *ma)
318 {
319 	int i;
320 
321 	el_free(ma->macro[0]);
322 	for (i = 0; i < ma->level; i++)
323 		ma->macro[i] = ma->macro[i + 1];
324 	ma->level--;
325 	ma->offset = 0;
326 }
327 
328 /* el_getc():
329  *	Read a character
330  */
331 public int
el_getc(EditLine * el,char * cp)332 el_getc(EditLine *el, char *cp)
333 {
334 	int num_read;
335 	c_macro_t *ma = &el->el_chared.c_macro;
336 
337 	term__flush(el);
338 	for (;;) {
339 		if (ma->level < 0) {
340 			if (!read_preread(el))
341 				break;
342 		}
343 
344 		if (ma->level < 0)
345 			break;
346 
347 		if (ma->macro[0][ma->offset] == '\0') {
348 			read_pop(ma);
349 			continue;
350 		}
351 
352 		*cp = ma->macro[0][ma->offset++] & 0377;
353 
354 		if (ma->macro[0][ma->offset] == '\0') {
355 			/* Needed for QuoteMode On */
356 			read_pop(ma);
357 		}
358 
359 		return (1);
360 	}
361 
362 #ifdef DEBUG_READ
363 	(void) fprintf(el->el_errfile, "Turning raw mode on\n");
364 #endif /* DEBUG_READ */
365 	if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
366 		return (0);
367 
368 #ifdef DEBUG_READ
369 	(void) fprintf(el->el_errfile, "Reading a character\n");
370 #endif /* DEBUG_READ */
371 	num_read = (*el->el_read.read_char)(el, cp);
372 #ifdef DEBUG_READ
373 	(void) fprintf(el->el_errfile, "Got it %c\n", *cp);
374 #endif /* DEBUG_READ */
375 	return (num_read);
376 }
377 
378 protected void
read_prepare(EditLine * el)379 read_prepare(EditLine *el)
380 {
381 	if (el->el_flags & HANDLE_SIGNALS)
382 		sig_set(el);
383 	if (el->el_flags & NO_TTY)
384 		return;
385 	if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
386 		tty_rawmode(el);
387 
388 	/* This is relatively cheap, and things go terribly wrong if
389 	   we have the wrong size. */
390 	el_resize(el);
391 	re_clear_display(el);	/* reset the display stuff */
392 	ch_reset(el, 0);
393 	re_refresh(el);		/* print the prompt */
394 
395 	if (el->el_flags & UNBUFFERED)
396 		term__flush(el);
397 }
398 
399 protected void
read_finish(EditLine * el)400 read_finish(EditLine *el)
401 {
402 	if ((el->el_flags & UNBUFFERED) == 0)
403 		(void) tty_cookedmode(el);
404 	if (el->el_flags & HANDLE_SIGNALS)
405 		sig_clr(el);
406 }
407 
408 public const char *
el_gets(EditLine * el,int * nread)409 el_gets(EditLine *el, int *nread)
410 {
411 	int retval;
412 	el_action_t cmdnum = 0;
413 	int num;		/* how many chars we have read at NL */
414 	char ch;
415 	int crlf = 0;
416 	int nrb;
417 #ifdef FIONREAD
418 	c_macro_t *ma = &el->el_chared.c_macro;
419 #endif /* FIONREAD */
420 
421 	if (nread == NULL)
422 		nread = &nrb;
423 	*nread = 0;
424 
425 	if (el->el_flags & NO_TTY) {
426 		char *cp = el->el_line.buffer;
427 		size_t idx;
428 
429 		while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
430 			/* make sure there is space for next character */
431 			if (cp + 1 >= el->el_line.limit) {
432 				idx = (cp - el->el_line.buffer);
433 				if (!ch_enlargebufs(el, 2))
434 					break;
435 				cp = &el->el_line.buffer[idx];
436 			}
437 			cp++;
438 			if (el->el_flags & UNBUFFERED)
439 				break;
440 			if (cp[-1] == '\r' || cp[-1] == '\n')
441 				break;
442 		}
443 		if (num == -1)
444 			el->el_errno = errno;
445 
446 		el->el_line.cursor = el->el_line.lastchar = cp;
447 		*cp = '\0';
448 		*nread = (int)(el->el_line.cursor - el->el_line.buffer);
449 		goto done;
450 	}
451 
452 
453 #ifdef FIONREAD
454 	if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
455 		long chrs = 0;
456 
457 		(void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
458 		if (chrs == 0) {
459 			if (tty_rawmode(el) < 0) {
460 				errno = 0;
461 				*nread = 0;
462 				return (NULL);
463 			}
464 		}
465 	}
466 #endif /* FIONREAD */
467 
468 	if ((el->el_flags & UNBUFFERED) == 0)
469 		read_prepare(el);
470 
471 	if (el->el_flags & EDIT_DISABLED) {
472 		char *cp;
473 		size_t idx;
474 
475 		if ((el->el_flags & UNBUFFERED) == 0)
476 			cp = el->el_line.buffer;
477 		else
478 			cp = el->el_line.lastchar;
479 
480 		term__flush(el);
481 
482 		while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
483 			/* make sure there is space next character */
484 			if (cp + 1 >= el->el_line.limit) {
485 				idx = (cp - el->el_line.buffer);
486 				if (!ch_enlargebufs(el, 2))
487 					break;
488 				cp = &el->el_line.buffer[idx];
489 			}
490 			cp++;
491 			crlf = cp[-1] == '\r' || cp[-1] == '\n';
492 			if (el->el_flags & UNBUFFERED)
493 				break;
494 			if (crlf)
495 				break;
496 		}
497 
498 		if (num == -1) {
499 			el->el_errno = errno;
500 		}
501 
502 		el->el_line.cursor = el->el_line.lastchar = cp;
503 		*cp = '\0';
504 		goto done;
505 	}
506 
507 	for (num = OKCMD; num == OKCMD;) {	/* while still editing this
508 						 * line */
509 #ifdef DEBUG_EDIT
510 		read_debug(el);
511 #endif /* DEBUG_EDIT */
512 		/* if EOF or error */
513 		if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
514 #ifdef DEBUG_READ
515 			(void) fprintf(el->el_errfile,
516 			    "Returning from el_gets %d\n", num);
517 #endif /* DEBUG_READ */
518 			break;
519 		}
520 		if ((size_t)cmdnum >= el->el_map.nfunc) {	/* BUG CHECK command */
521 #ifdef DEBUG_EDIT
522 			(void) fprintf(el->el_errfile,
523 			    "ERROR: illegal command from key 0%o\r\n", ch);
524 #endif /* DEBUG_EDIT */
525 			continue;	/* try again */
526 		}
527 		/* now do the real command */
528 #ifdef DEBUG_READ
529 		{
530 			el_bindings_t *b;
531 			for (b = el->el_map.help; b->name; b++)
532 				if (b->func == cmdnum)
533 					break;
534 			if (b->name)
535 				(void) fprintf(el->el_errfile,
536 				    "Executing %s\n", b->name);
537 			else
538 				(void) fprintf(el->el_errfile,
539 				    "Error command = %d\n", cmdnum);
540 		}
541 #endif /* DEBUG_READ */
542 		/* vi redo needs these way down the levels... */
543 		el->el_state.thiscmd = cmdnum;
544 		el->el_state.thisch = ch;
545 		if (el->el_map.type == MAP_VI &&
546 		    el->el_map.current == el->el_map.key &&
547 		    el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
548 			if (cmdnum == VI_DELETE_PREV_CHAR &&
549 			    el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
550 			    && isprint((unsigned char)el->el_chared.c_redo.pos[-1]))
551 				el->el_chared.c_redo.pos--;
552 			else
553 				*el->el_chared.c_redo.pos++ = ch;
554 		}
555 		retval = (*el->el_map.func[cmdnum]) (el, ch);
556 #ifdef DEBUG_READ
557 		(void) fprintf(el->el_errfile,
558 			"Returned state %d\n", retval );
559 #endif /* DEBUG_READ */
560 
561 		/* save the last command here */
562 		el->el_state.lastcmd = cmdnum;
563 
564 		/* use any return value */
565 		switch (retval) {
566 		case CC_CURSOR:
567 			re_refresh_cursor(el);
568 			break;
569 
570 		case CC_REDISPLAY:
571 			re_clear_lines(el);
572 			re_clear_display(el);
573 			/* FALLTHROUGH */
574 
575 		case CC_REFRESH:
576 			re_refresh(el);
577 			break;
578 
579 		case CC_REFRESH_BEEP:
580 			re_refresh(el);
581 			term_beep(el);
582 			break;
583 
584 		case CC_NORM:	/* normal char */
585 			break;
586 
587 		case CC_ARGHACK:	/* Suggested by Rich Salz */
588 			/* <rsalz@pineapple.bbn.com> */
589 			continue;	/* keep going... */
590 
591 		case CC_EOF:	/* end of file typed */
592 			if ((el->el_flags & UNBUFFERED) == 0)
593 				num = 0;
594 			else if (num == -1) {
595 				*el->el_line.lastchar++ = CONTROL('d');
596 				el->el_line.cursor = el->el_line.lastchar;
597 				num = 1;
598 			}
599 			break;
600 
601 		case CC_NEWLINE:	/* normal end of line */
602 			num = (int)(el->el_line.lastchar - el->el_line.buffer);
603 			break;
604 
605 		case CC_FATAL:	/* fatal error, reset to known state */
606 #ifdef DEBUG_READ
607 			(void) fprintf(el->el_errfile,
608 			    "*** editor fatal ERROR ***\r\n\n");
609 #endif /* DEBUG_READ */
610 			/* put (real) cursor in a known place */
611 			re_clear_display(el);	/* reset the display stuff */
612 			ch_reset(el, 1);	/* reset the input pointers */
613 			re_refresh(el);	/* print the prompt again */
614 			break;
615 
616 		case CC_ERROR:
617 		default:	/* functions we don't know about */
618 #ifdef DEBUG_READ
619 			(void) fprintf(el->el_errfile,
620 			    "*** editor ERROR ***\r\n\n");
621 #endif /* DEBUG_READ */
622 			term_beep(el);
623 			term__flush(el);
624 			break;
625 		}
626 		el->el_state.argument = 1;
627 		el->el_state.doingarg = 0;
628 		el->el_chared.c_vcmd.action = NOP;
629 		if (el->el_flags & UNBUFFERED)
630 			break;
631 	}
632 
633 	term__flush(el);		/* flush any buffered output */
634 	/* make sure the tty is set up correctly */
635 	if ((el->el_flags & UNBUFFERED) == 0) {
636 		read_finish(el);
637 		*nread = num != -1 ? num : 0;
638 	} else {
639 		*nread = (int)(el->el_line.lastchar - el->el_line.buffer);
640 	}
641 done:
642 	if (*nread == 0) {
643 		if (num == -1) {
644 			*nread = -1;
645 			errno = el->el_errno;
646 		}
647 		return NULL;
648 	} else
649 		return el->el_line.buffer;
650 }
651