xref: /netbsd-src/lib/libedit/read.c (revision 4b896b232495b7a9b8b94a1cf1e21873296d53b8)
1 /*	$NetBSD: read.c,v 1.33 2004/02/27 14:52:18 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 1.33 2004/02/27 14:52:18 christos Exp $");
41 #endif
42 #endif /* not lint && not SCCSID */
43 
44 /*
45  * read.c: Clean this junk up! This is horrible code.
46  *	   Terminal read functions
47  */
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <unistd.h>
51 #include <stdlib.h>
52 #include "el.h"
53 
54 #define	OKCMD	-1
55 
56 private int	read__fixio(int, int);
57 private int	read_preread(EditLine *);
58 private int	read_char(EditLine *, char *);
59 private int	read_getcmd(EditLine *, el_action_t *, char *);
60 
61 /* read_init():
62  *	Initialize the read stuff
63  */
64 protected int
65 read_init(EditLine *el)
66 {
67 	/* builtin read_char */
68 	el->el_read.read_char = read_char;
69 	return 0;
70 }
71 
72 
73 /* el_read_setfn():
74  *	Set the read char function to the one provided.
75  *	If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
76  */
77 protected int
78 el_read_setfn(EditLine *el, el_rfunc_t rc)
79 {
80 	el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
81 	return 0;
82 }
83 
84 
85 /* el_read_getfn():
86  *	return the current read char function, or EL_BUILTIN_GETCFN
87  *	if it is the default one
88  */
89 protected el_rfunc_t
90 el_read_getfn(EditLine *el)
91 {
92        return (el->el_read.read_char == read_char) ?
93 	    EL_BUILTIN_GETCFN : el->el_read.read_char;
94 }
95 
96 
97 #ifndef MIN
98 #define MIN(A,B) ((A) < (B) ? (A) : (B))
99 #endif
100 
101 #ifdef DEBUG_EDIT
102 private void
103 read_debug(EditLine *el)
104 {
105 
106 	if (el->el_line.cursor > el->el_line.lastchar)
107 		(void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
108 	if (el->el_line.cursor < el->el_line.buffer)
109 		(void) fprintf(el->el_errfile, "cursor < buffer\r\n");
110 	if (el->el_line.cursor > el->el_line.limit)
111 		(void) fprintf(el->el_errfile, "cursor > limit\r\n");
112 	if (el->el_line.lastchar > el->el_line.limit)
113 		(void) fprintf(el->el_errfile, "lastchar > limit\r\n");
114 	if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
115 		(void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
116 }
117 #endif /* DEBUG_EDIT */
118 
119 
120 /* read__fixio():
121  *	Try to recover from a read error
122  */
123 /* ARGSUSED */
124 private int
125 read__fixio(int fd __attribute__((__unused__)), int e)
126 {
127 
128 	switch (e) {
129 	case -1:		/* Make sure that the code is reachable */
130 
131 #ifdef EWOULDBLOCK
132 	case EWOULDBLOCK:
133 #ifndef TRY_AGAIN
134 #define	TRY_AGAIN
135 #endif
136 #endif /* EWOULDBLOCK */
137 
138 #if defined(POSIX) && defined(EAGAIN)
139 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
140 	case EAGAIN:
141 #ifndef TRY_AGAIN
142 #define	TRY_AGAIN
143 #endif
144 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
145 #endif /* POSIX && EAGAIN */
146 
147 		e = 0;
148 #ifdef TRY_AGAIN
149 #if defined(F_SETFL) && defined(O_NDELAY)
150 		if ((e = fcntl(fd, F_GETFL, 0)) == -1)
151 			return (-1);
152 
153 		if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
154 			return (-1);
155 		else
156 			e = 1;
157 #endif /* F_SETFL && O_NDELAY */
158 
159 #ifdef FIONBIO
160 		{
161 			int zero = 0;
162 
163 			if (ioctl(fd, FIONBIO, (ioctl_t) & zero) == -1)
164 				return (-1);
165 			else
166 				e = 1;
167 		}
168 #endif /* FIONBIO */
169 
170 #endif /* TRY_AGAIN */
171 		return (e ? 0 : -1);
172 
173 	case EINTR:
174 		return (0);
175 
176 	default:
177 		return (-1);
178 	}
179 }
180 
181 
182 /* read_preread():
183  *	Try to read the stuff in the input queue;
184  */
185 private int
186 read_preread(EditLine *el)
187 {
188 	int chrs = 0;
189 
190 	if (el->el_tty.t_mode == ED_IO)
191 		return (0);
192 
193 #ifdef FIONREAD
194 	(void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
195 	if (chrs > 0) {
196 		char buf[EL_BUFSIZ];
197 
198 		chrs = read(el->el_infd, buf,
199 		    (size_t) MIN(chrs, EL_BUFSIZ - 1));
200 		if (chrs > 0) {
201 			buf[chrs] = '\0';
202 			el_push(el, buf);
203 		}
204 	}
205 #endif /* FIONREAD */
206 
207 	return (chrs > 0);
208 }
209 
210 
211 /* el_push():
212  *	Push a macro
213  */
214 public void
215 el_push(EditLine *el, char *str)
216 {
217 	c_macro_t *ma = &el->el_chared.c_macro;
218 
219 	if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
220 		ma->level++;
221 		if ((ma->macro[ma->level] = el_strdup(str)) != NULL)
222 			return;
223 		ma->level--;
224 	}
225 	term_beep(el);
226 	term__flush();
227 }
228 
229 
230 /* read_getcmd():
231  *	Return next command from the input stream.
232  */
233 private int
234 read_getcmd(EditLine *el, el_action_t *cmdnum, char *ch)
235 {
236 	el_action_t cmd;
237 	int num;
238 
239 	do {
240 		if ((num = el_getc(el, ch)) != 1)	/* if EOF or error */
241 			return (num);
242 
243 #ifdef	KANJI
244 		if ((*ch & 0200)) {
245 			el->el_state.metanext = 0;
246 			cmd = CcViMap[' '];
247 			break;
248 		} else
249 #endif /* KANJI */
250 
251 		if (el->el_state.metanext) {
252 			el->el_state.metanext = 0;
253 			*ch |= 0200;
254 		}
255 		cmd = el->el_map.current[(unsigned char) *ch];
256 		if (cmd == ED_SEQUENCE_LEAD_IN) {
257 			key_value_t val;
258 			switch (key_get(el, ch, &val)) {
259 			case XK_CMD:
260 				cmd = val.cmd;
261 				break;
262 			case XK_STR:
263 				el_push(el, val.str);
264 				break;
265 #ifdef notyet
266 			case XK_EXE:
267 				/* XXX: In the future to run a user function */
268 				RunCommand(val.str);
269 				break;
270 #endif
271 			default:
272 				EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
273 				break;
274 			}
275 		}
276 		if (el->el_map.alt == NULL)
277 			el->el_map.current = el->el_map.key;
278 	} while (cmd == ED_SEQUENCE_LEAD_IN);
279 	*cmdnum = cmd;
280 	return (OKCMD);
281 }
282 
283 
284 /* read_char():
285  *	Read a character from the tty.
286  */
287 private int
288 read_char(EditLine *el, char *cp)
289 {
290 	int num_read;
291 	int tried = 0;
292 
293 	while ((num_read = read(el->el_infd, cp, 1)) == -1)
294 		if (!tried && read__fixio(el->el_infd, errno) == 0)
295 			tried = 1;
296 		else {
297 			*cp = '\0';
298 			return (-1);
299 		}
300 
301 	return (num_read);
302 }
303 
304 
305 /* el_getc():
306  *	Read a character
307  */
308 public int
309 el_getc(EditLine *el, char *cp)
310 {
311 	int num_read;
312 	c_macro_t *ma = &el->el_chared.c_macro;
313 
314 	term__flush();
315 	for (;;) {
316 		if (ma->level < 0) {
317 			if (!read_preread(el))
318 				break;
319 		}
320 		if (ma->level < 0)
321 			break;
322 
323 		if (ma->macro[ma->level][ma->offset] == '\0') {
324 			el_free(ma->macro[ma->level--]);
325 			ma->offset = 0;
326 			continue;
327 		}
328 		*cp = ma->macro[ma->level][ma->offset++] & 0377;
329 		if (ma->macro[ma->level][ma->offset] == '\0') {
330 			/* Needed for QuoteMode On */
331 			el_free(ma->macro[ma->level--]);
332 			ma->offset = 0;
333 		}
334 		return (1);
335 	}
336 
337 #ifdef DEBUG_READ
338 	(void) fprintf(el->el_errfile, "Turning raw mode on\n");
339 #endif /* DEBUG_READ */
340 	if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
341 		return (0);
342 
343 #ifdef DEBUG_READ
344 	(void) fprintf(el->el_errfile, "Reading a character\n");
345 #endif /* DEBUG_READ */
346 	num_read = (*el->el_read.read_char)(el, cp);
347 #ifdef DEBUG_READ
348 	(void) fprintf(el->el_errfile, "Got it %c\n", *cp);
349 #endif /* DEBUG_READ */
350 	return (num_read);
351 }
352 
353 protected void
354 read_prepare(EditLine *el)
355 {
356 	if (el->el_flags & HANDLE_SIGNALS)
357 		sig_set(el);
358 	if (el->el_flags & NO_TTY)
359 		return;
360 	if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
361 		tty_rawmode(el);
362 
363 	/* This is relatively cheap, and things go terribly wrong if
364 	   we have the wrong size. */
365 	el_resize(el);
366 	re_clear_display(el);	/* reset the display stuff */
367 	ch_reset(el);
368 	re_refresh(el);		/* print the prompt */
369 }
370 
371 protected void
372 read_finish(EditLine *el)
373 {
374 	if ((el->el_flags & UNBUFFERED) == 0)
375 		(void) tty_cookedmode(el);
376 	if (el->el_flags & HANDLE_SIGNALS)
377 		sig_clr(el);
378 }
379 
380 public const char *
381 el_gets(EditLine *el, int *nread)
382 {
383 	int retval;
384 	el_action_t cmdnum = 0;
385 	int num;		/* how many chars we have read at NL */
386 	char ch;
387 	int crlf = 0;
388 #ifdef FIONREAD
389 	c_macro_t *ma = &el->el_chared.c_macro;
390 #endif /* FIONREAD */
391 
392 	if (el->el_flags & NO_TTY) {
393 		char *cp = el->el_line.buffer;
394 		size_t idx;
395 
396 		while ((*el->el_read.read_char)(el, cp) == 1) {
397 			/* make sure there is space for next character */
398 			if (cp + 1 >= el->el_line.limit) {
399 				idx = (cp - el->el_line.buffer);
400 				if (!ch_enlargebufs(el, 2))
401 					break;
402 				cp = &el->el_line.buffer[idx];
403 			}
404 			cp++;
405 			if (el->el_flags & UNBUFFERED)
406 				break;
407 			if (cp[-1] == '\r' || cp[-1] == '\n')
408 				break;
409 		}
410 
411 		el->el_line.cursor = el->el_line.lastchar = cp;
412 		*cp = '\0';
413 		if (nread)
414 			*nread = el->el_line.cursor - el->el_line.buffer;
415 		return (el->el_line.buffer);
416 	}
417 
418 
419 #ifdef FIONREAD
420 	if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
421 		long chrs = 0;
422 
423 		(void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
424 		if (chrs == 0) {
425 			if (tty_rawmode(el) < 0) {
426 				if (nread)
427 					*nread = 0;
428 				return (NULL);
429 			}
430 		}
431 	}
432 #endif /* FIONREAD */
433 
434 	if ((el->el_flags & UNBUFFERED) == 0)
435 		read_prepare(el);
436 
437 	if (el->el_flags & EDIT_DISABLED) {
438 		char *cp = el->el_line.buffer;
439 		size_t idx;
440 
441 		term__flush();
442 
443 		while ((*el->el_read.read_char)(el, cp) == 1) {
444 			/* make sure there is space next character */
445 			if (cp + 1 >= el->el_line.limit) {
446 				idx = (cp - el->el_line.buffer);
447 				if (!ch_enlargebufs(el, 2))
448 					break;
449 				cp = &el->el_line.buffer[idx];
450 			}
451 			if (*cp == 4)	/* ought to be stty eof */
452 				break;
453 			cp++;
454 			crlf = cp[-1] == '\r' || cp[-1] == '\n';
455 			if (el->el_flags & UNBUFFERED)
456 				break;
457 			if (crlf)
458 				break;
459 		}
460 
461 		el->el_line.cursor = el->el_line.lastchar = cp;
462 		*cp = '\0';
463 		if (nread)
464 			*nread = el->el_line.cursor - el->el_line.buffer;
465 		return (el->el_line.buffer);
466 	}
467 
468 	for (num = OKCMD; num == OKCMD;) {	/* while still editing this
469 						 * line */
470 #ifdef DEBUG_EDIT
471 		read_debug(el);
472 #endif /* DEBUG_EDIT */
473 		/* if EOF or error */
474 		if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
475 #ifdef DEBUG_READ
476 			(void) fprintf(el->el_errfile,
477 			    "Returning from el_gets %d\n", num);
478 #endif /* DEBUG_READ */
479 			break;
480 		}
481 		if ((uint)cmdnum >= el->el_map.nfunc) {	/* BUG CHECK command */
482 #ifdef DEBUG_EDIT
483 			(void) fprintf(el->el_errfile,
484 			    "ERROR: illegal command from key 0%o\r\n", ch);
485 #endif /* DEBUG_EDIT */
486 			continue;	/* try again */
487 		}
488 		/* now do the real command */
489 #ifdef DEBUG_READ
490 		{
491 			el_bindings_t *b;
492 			for (b = el->el_map.help; b->name; b++)
493 				if (b->func == cmdnum)
494 					break;
495 			if (b->name)
496 				(void) fprintf(el->el_errfile,
497 				    "Executing %s\n", b->name);
498 			else
499 				(void) fprintf(el->el_errfile,
500 				    "Error command = %d\n", cmdnum);
501 		}
502 #endif /* DEBUG_READ */
503 		/* vi redo needs these way down the levels... */
504 		el->el_state.thiscmd = cmdnum;
505 		el->el_state.thisch = ch;
506 		if (el->el_map.type == MAP_VI &&
507 		    el->el_map.current == el->el_map.key &&
508 		    el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
509 			if (cmdnum == VI_DELETE_PREV_CHAR &&
510 			    el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
511 			    && isprint((unsigned char)el->el_chared.c_redo.pos[-1]))
512 				el->el_chared.c_redo.pos--;
513 			else
514 				*el->el_chared.c_redo.pos++ = ch;
515 		}
516 		retval = (*el->el_map.func[cmdnum]) (el, ch);
517 #ifdef DEBUG_READ
518 		(void) fprintf(el->el_errfile,
519 			"Returned state %d\n", retval );
520 #endif /* DEBUG_READ */
521 
522 		/* save the last command here */
523 		el->el_state.lastcmd = cmdnum;
524 
525 		/* use any return value */
526 		switch (retval) {
527 		case CC_CURSOR:
528 			re_refresh_cursor(el);
529 			break;
530 
531 		case CC_REDISPLAY:
532 			re_clear_lines(el);
533 			re_clear_display(el);
534 			/* FALLTHROUGH */
535 
536 		case CC_REFRESH:
537 			re_refresh(el);
538 			break;
539 
540 		case CC_REFRESH_BEEP:
541 			re_refresh(el);
542 			term_beep(el);
543 			break;
544 
545 		case CC_NORM:	/* normal char */
546 			break;
547 
548 		case CC_ARGHACK:	/* Suggested by Rich Salz */
549 			/* <rsalz@pineapple.bbn.com> */
550 			continue;	/* keep going... */
551 
552 		case CC_EOF:	/* end of file typed */
553 			if ((el->el_flags & UNBUFFERED) == 0)
554 				num = 0;
555 			else if (num == -1) {
556 				*el->el_line.lastchar++ = CONTROL('d');
557 				el->el_line.cursor = el->el_line.lastchar;
558 				num = 1;
559 			}
560 			break;
561 
562 		case CC_NEWLINE:	/* normal end of line */
563 			num = el->el_line.lastchar - el->el_line.buffer;
564 			break;
565 
566 		case CC_FATAL:	/* fatal error, reset to known state */
567 #ifdef DEBUG_READ
568 			(void) fprintf(el->el_errfile,
569 			    "*** editor fatal ERROR ***\r\n\n");
570 #endif /* DEBUG_READ */
571 			/* put (real) cursor in a known place */
572 			re_clear_display(el);	/* reset the display stuff */
573 			ch_reset(el);	/* reset the input pointers */
574 			re_refresh(el);	/* print the prompt again */
575 			break;
576 
577 		case CC_ERROR:
578 		default:	/* functions we don't know about */
579 #ifdef DEBUG_READ
580 			(void) fprintf(el->el_errfile,
581 			    "*** editor ERROR ***\r\n\n");
582 #endif /* DEBUG_READ */
583 			term_beep(el);
584 			term__flush();
585 			break;
586 		}
587 		el->el_state.argument = 1;
588 		el->el_state.doingarg = 0;
589 		el->el_chared.c_vcmd.action = NOP;
590 		if (el->el_flags & UNBUFFERED)
591 			break;
592 	}
593 
594 	term__flush();		/* flush any buffered output */
595 	/* make sure the tty is set up correctly */
596 	if ((el->el_flags & UNBUFFERED) == 0) {
597 		read_finish(el);
598 		if (nread)
599 			*nread = num;
600 	} else {
601 		if (nread)
602 			*nread = el->el_line.lastchar - el->el_line.buffer;
603 	}
604 	return (num ? el->el_line.buffer : NULL);
605 }
606