xref: /netbsd-src/lib/libedit/read.c (revision 001c68bd94f75ce9270b69227c4199fbf34ee396)
1 /*	$NetBSD: read.c,v 1.25 2003/06/19 15:55:06 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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include "config.h"
40 #if !defined(lint) && !defined(SCCSID)
41 #if 0
42 static char sccsid[] = "@(#)read.c	8.1 (Berkeley) 6/4/93";
43 #else
44 __RCSID("$NetBSD: read.c,v 1.25 2003/06/19 15:55:06 christos Exp $");
45 #endif
46 #endif /* not lint && not SCCSID */
47 
48 /*
49  * read.c: Clean this junk up! This is horrible code.
50  *	   Terminal read functions
51  */
52 #include <errno.h>
53 #include <unistd.h>
54 #include <stdlib.h>
55 #include "el.h"
56 
57 #define	OKCMD	-1
58 
59 private int	read__fixio(int, int);
60 private int	read_preread(EditLine *);
61 private int	read_char(EditLine *, char *);
62 private int	read_getcmd(EditLine *, el_action_t *, char *);
63 
64 /* read_init():
65  *	Initialize the read stuff
66  */
67 protected int
68 read_init(EditLine *el)
69 {
70 	/* builtin read_char */
71 	el->el_read.read_char = read_char;
72 	return 0;
73 }
74 
75 
76 /* el_read_setfn():
77  *	Set the read char function to the one provided.
78  *	If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
79  */
80 protected int
81 el_read_setfn(EditLine *el, el_rfunc_t rc)
82 {
83 	el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
84 	return 0;
85 }
86 
87 
88 /* el_read_getfn():
89  *	return the current read char function, or EL_BUILTIN_GETCFN
90  *	if it is the default one
91  */
92 protected el_rfunc_t
93 el_read_getfn(EditLine *el)
94 {
95        return (el->el_read.read_char == read_char) ?
96 	    EL_BUILTIN_GETCFN : el->el_read.read_char;
97 }
98 
99 
100 #ifndef MIN
101 #define MIN(A,B) ((A) < (B) ? (A) : (B))
102 #endif
103 
104 #ifdef DEBUG_EDIT
105 private void
106 read_debug(EditLine *el)
107 {
108 
109 	if (el->el_line.cursor > el->el_line.lastchar)
110 		(void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
111 	if (el->el_line.cursor < el->el_line.buffer)
112 		(void) fprintf(el->el_errfile, "cursor < buffer\r\n");
113 	if (el->el_line.cursor > el->el_line.limit)
114 		(void) fprintf(el->el_errfile, "cursor > limit\r\n");
115 	if (el->el_line.lastchar > el->el_line.limit)
116 		(void) fprintf(el->el_errfile, "lastchar > limit\r\n");
117 	if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
118 		(void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
119 }
120 #endif /* DEBUG_EDIT */
121 
122 
123 /* read__fixio():
124  *	Try to recover from a read error
125  */
126 /* ARGSUSED */
127 private int
128 read__fixio(int fd __attribute__((__unused__)), int e)
129 {
130 
131 	switch (e) {
132 	case -1:		/* Make sure that the code is reachable */
133 
134 #ifdef EWOULDBLOCK
135 	case EWOULDBLOCK:
136 #ifndef TRY_AGAIN
137 #define	TRY_AGAIN
138 #endif
139 #endif /* EWOULDBLOCK */
140 
141 #if defined(POSIX) && defined(EAGAIN)
142 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
143 	case EAGAIN:
144 #ifndef TRY_AGAIN
145 #define	TRY_AGAIN
146 #endif
147 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
148 #endif /* POSIX && EAGAIN */
149 
150 		e = 0;
151 #ifdef TRY_AGAIN
152 #if defined(F_SETFL) && defined(O_NDELAY)
153 		if ((e = fcntl(fd, F_GETFL, 0)) == -1)
154 			return (-1);
155 
156 		if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
157 			return (-1);
158 		else
159 			e = 1;
160 #endif /* F_SETFL && O_NDELAY */
161 
162 #ifdef FIONBIO
163 		{
164 			int zero = 0;
165 
166 			if (ioctl(fd, FIONBIO, (ioctl_t) & zero) == -1)
167 				return (-1);
168 			else
169 				e = 1;
170 		}
171 #endif /* FIONBIO */
172 
173 #endif /* TRY_AGAIN */
174 		return (e ? 0 : -1);
175 
176 	case EINTR:
177 		return (0);
178 
179 	default:
180 		return (-1);
181 	}
182 }
183 
184 
185 /* read_preread():
186  *	Try to read the stuff in the input queue;
187  */
188 private int
189 read_preread(EditLine *el)
190 {
191 	int chrs = 0;
192 
193 	if (el->el_chared.c_macro.nline) {
194 		el_free((ptr_t) el->el_chared.c_macro.nline);
195 		el->el_chared.c_macro.nline = NULL;
196 	}
197 	if (el->el_tty.t_mode == ED_IO)
198 		return (0);
199 
200 #ifdef FIONREAD
201 	(void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
202 	if (chrs > 0) {
203 		char buf[EL_BUFSIZ];
204 
205 		chrs = read(el->el_infd, buf,
206 		    (size_t) MIN(chrs, EL_BUFSIZ - 1));
207 		if (chrs > 0) {
208 			buf[chrs] = '\0';
209 			el->el_chared.c_macro.nline = strdup(buf);
210 			el_push(el, el->el_chared.c_macro.nline);
211 		}
212 	}
213 #endif /* FIONREAD */
214 
215 	return (chrs > 0);
216 }
217 
218 
219 /* el_push():
220  *	Push a macro
221  */
222 public void
223 el_push(EditLine *el, char *str)
224 {
225 	c_macro_t *ma = &el->el_chared.c_macro;
226 
227 	if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
228 		ma->level++;
229 		ma->macro[ma->level] = str;
230 	} else {
231 		term_beep(el);
232 		term__flush();
233 	}
234 }
235 
236 
237 /* read_getcmd():
238  *	Return next command from the input stream.
239  */
240 private int
241 read_getcmd(EditLine *el, el_action_t *cmdnum, char *ch)
242 {
243 	el_action_t cmd;
244 	int num;
245 
246 	do {
247 		if ((num = el_getc(el, ch)) != 1)	/* if EOF or error */
248 			return (num);
249 
250 #ifdef	KANJI
251 		if ((*ch & 0200)) {
252 			el->el_state.metanext = 0;
253 			cmd = CcViMap[' '];
254 			break;
255 		} else
256 #endif /* KANJI */
257 
258 		if (el->el_state.metanext) {
259 			el->el_state.metanext = 0;
260 			*ch |= 0200;
261 		}
262 		cmd = el->el_map.current[(unsigned char) *ch];
263 		if (cmd == ED_SEQUENCE_LEAD_IN) {
264 			key_value_t val;
265 			switch (key_get(el, ch, &val)) {
266 			case XK_CMD:
267 				cmd = val.cmd;
268 				break;
269 			case XK_STR:
270 				el_push(el, val.str);
271 				break;
272 #ifdef notyet
273 			case XK_EXE:
274 				/* XXX: In the future to run a user function */
275 				RunCommand(val.str);
276 				break;
277 #endif
278 			default:
279 				EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
280 				break;
281 			}
282 		}
283 		if (el->el_map.alt == NULL)
284 			el->el_map.current = el->el_map.key;
285 	} while (cmd == ED_SEQUENCE_LEAD_IN);
286 	*cmdnum = cmd;
287 	return (OKCMD);
288 }
289 
290 
291 /* read_char():
292  *	Read a character from the tty.
293  */
294 private int
295 read_char(EditLine *el, char *cp)
296 {
297 	int num_read;
298 	int tried = 0;
299 
300 	while ((num_read = read(el->el_infd, cp, 1)) == -1)
301 		if (!tried && read__fixio(el->el_infd, errno) == 0)
302 			tried = 1;
303 		else {
304 			*cp = '\0';
305 			return (-1);
306 		}
307 
308 	return (num_read);
309 }
310 
311 
312 /* el_getc():
313  *	Read a character
314  */
315 public int
316 el_getc(EditLine *el, char *cp)
317 {
318 	int num_read;
319 	c_macro_t *ma = &el->el_chared.c_macro;
320 
321 	term__flush();
322 	for (;;) {
323 		if (ma->level < 0) {
324 			if (!read_preread(el))
325 				break;
326 		}
327 		if (ma->level < 0)
328 			break;
329 
330 		if (*ma->macro[ma->level] == 0) {
331 			ma->level--;
332 			continue;
333 		}
334 		*cp = *ma->macro[ma->level]++ & 0377;
335 		if (*ma->macro[ma->level] == 0) {	/* Needed for QuoteMode
336 							 * On */
337 			ma->level--;
338 		}
339 		return (1);
340 	}
341 
342 #ifdef DEBUG_READ
343 	(void) fprintf(el->el_errfile, "Turning raw mode on\n");
344 #endif /* DEBUG_READ */
345 	if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
346 		return (0);
347 
348 #ifdef DEBUG_READ
349 	(void) fprintf(el->el_errfile, "Reading a character\n");
350 #endif /* DEBUG_READ */
351 	num_read = (*el->el_read.read_char)(el, cp);
352 #ifdef DEBUG_READ
353 	(void) fprintf(el->el_errfile, "Got it %c\n", *cp);
354 #endif /* DEBUG_READ */
355 	return (num_read);
356 }
357 
358 
359 public const char *
360 el_gets(EditLine *el, int *nread)
361 {
362 	int retval;
363 	el_action_t cmdnum = 0;
364 	int num;		/* how many chars we have read at NL */
365 	char ch;
366 #ifdef FIONREAD
367 	c_macro_t *ma = &el->el_chared.c_macro;
368 #endif /* FIONREAD */
369 
370 	if (el->el_flags & HANDLE_SIGNALS)
371 		sig_set(el);
372 
373 	if (el->el_flags & NO_TTY) {
374 		char *cp = el->el_line.buffer;
375 		size_t idx;
376 
377 		while ((*el->el_read.read_char)(el, cp) == 1) {
378 			/* make sure there is space for next character */
379 			if (cp + 1 >= el->el_line.limit) {
380 				idx = (cp - el->el_line.buffer);
381 				if (!ch_enlargebufs(el, 2))
382 					break;
383 				cp = &el->el_line.buffer[idx];
384 			}
385 			cp++;
386 			if (cp[-1] == '\r' || cp[-1] == '\n')
387 				break;
388 		}
389 
390 		el->el_line.cursor = el->el_line.lastchar = cp;
391 		*cp = '\0';
392 		if (nread)
393 			*nread = el->el_line.cursor - el->el_line.buffer;
394 		return (el->el_line.buffer);
395 	}
396 
397 	/* This is relatively cheap, and things go terribly wrong if
398 	   we have the wrong size. */
399 	el_resize(el);
400 
401 	re_clear_display(el);	/* reset the display stuff */
402 	ch_reset(el);
403 
404 #ifdef FIONREAD
405 	if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
406 		long chrs = 0;
407 
408 		(void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
409 		if (chrs == 0) {
410 			if (tty_rawmode(el) < 0) {
411 				if (nread)
412 					*nread = 0;
413 				return (NULL);
414 			}
415 		}
416 	}
417 #endif /* FIONREAD */
418 
419 	re_refresh(el);		/* print the prompt */
420 
421 	if (el->el_flags & EDIT_DISABLED) {
422 		char *cp = el->el_line.buffer;
423 		size_t idx;
424 
425 		term__flush();
426 
427 		while ((*el->el_read.read_char)(el, cp) == 1) {
428 			/* make sure there is space next character */
429 			if (cp + 1 >= el->el_line.limit) {
430 				idx = (cp - el->el_line.buffer);
431 				if (!ch_enlargebufs(el, 2))
432 					break;
433 				cp = &el->el_line.buffer[idx];
434 			}
435 			if (*cp == 4)	/* ought to be stty eof */
436 				break;
437 			cp++;
438 			if (cp[-1] == '\r' || cp[-1] == '\n')
439 				break;
440 		}
441 
442 		el->el_line.cursor = el->el_line.lastchar = cp;
443 		*cp = '\0';
444 		if (nread)
445 			*nread = el->el_line.cursor - el->el_line.buffer;
446 		return (el->el_line.buffer);
447 	}
448 
449 	for (num = OKCMD; num == OKCMD;) {	/* while still editing this
450 						 * line */
451 #ifdef DEBUG_EDIT
452 		read_debug(el);
453 #endif /* DEBUG_EDIT */
454 		/* if EOF or error */
455 		if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
456 #ifdef DEBUG_READ
457 			(void) fprintf(el->el_errfile,
458 			    "Returning from el_gets %d\n", num);
459 #endif /* DEBUG_READ */
460 			break;
461 		}
462 		if ((uint)cmdnum >= el->el_map.nfunc) {	/* BUG CHECK command */
463 #ifdef DEBUG_EDIT
464 			(void) fprintf(el->el_errfile,
465 			    "ERROR: illegal command from key 0%o\r\n", ch);
466 #endif /* DEBUG_EDIT */
467 			continue;	/* try again */
468 		}
469 		/* now do the real command */
470 #ifdef DEBUG_READ
471 		{
472 			el_bindings_t *b;
473 			for (b = el->el_map.help; b->name; b++)
474 				if (b->func == cmdnum)
475 					break;
476 			if (b->name)
477 				(void) fprintf(el->el_errfile,
478 				    "Executing %s\n", b->name);
479 			else
480 				(void) fprintf(el->el_errfile,
481 				    "Error command = %d\n", cmdnum);
482 		}
483 #endif /* DEBUG_READ */
484 		/* vi redo needs these way down the levels... */
485 		el->el_state.thiscmd = cmdnum;
486 		el->el_state.thisch = ch;
487 		if (el->el_map.type == MAP_VI &&
488 		    el->el_map.current == el->el_map.key &&
489 		    el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
490 			if (cmdnum == VI_DELETE_PREV_CHAR &&
491 			    el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
492 			    && isprint(el->el_chared.c_redo.pos[-1]))
493 				el->el_chared.c_redo.pos--;
494 			else
495 				*el->el_chared.c_redo.pos++ = ch;
496 		}
497 		retval = (*el->el_map.func[cmdnum]) (el, ch);
498 #ifdef DEBUG_READ
499 		(void) fprintf(el->el_errfile,
500 			"Returned state %d\n", retval );
501 #endif /* DEBUG_READ */
502 
503 		/* save the last command here */
504 		el->el_state.lastcmd = cmdnum;
505 
506 		/* use any return value */
507 		switch (retval) {
508 		case CC_CURSOR:
509 			re_refresh_cursor(el);
510 			break;
511 
512 		case CC_REDISPLAY:
513 			re_clear_lines(el);
514 			re_clear_display(el);
515 			/* FALLTHROUGH */
516 
517 		case CC_REFRESH:
518 			re_refresh(el);
519 			break;
520 
521 		case CC_REFRESH_BEEP:
522 			re_refresh(el);
523 			term_beep(el);
524 			break;
525 
526 		case CC_NORM:	/* normal char */
527 			break;
528 
529 		case CC_ARGHACK:	/* Suggested by Rich Salz */
530 			/* <rsalz@pineapple.bbn.com> */
531 			continue;	/* keep going... */
532 
533 		case CC_EOF:	/* end of file typed */
534 			num = 0;
535 			break;
536 
537 		case CC_NEWLINE:	/* normal end of line */
538 			num = el->el_line.lastchar - el->el_line.buffer;
539 			break;
540 
541 		case CC_FATAL:	/* fatal error, reset to known state */
542 #ifdef DEBUG_READ
543 			(void) fprintf(el->el_errfile,
544 			    "*** editor fatal ERROR ***\r\n\n");
545 #endif /* DEBUG_READ */
546 			/* put (real) cursor in a known place */
547 			re_clear_display(el);	/* reset the display stuff */
548 			ch_reset(el);	/* reset the input pointers */
549 			re_refresh(el);	/* print the prompt again */
550 			break;
551 
552 		case CC_ERROR:
553 		default:	/* functions we don't know about */
554 #ifdef DEBUG_READ
555 			(void) fprintf(el->el_errfile,
556 			    "*** editor ERROR ***\r\n\n");
557 #endif /* DEBUG_READ */
558 			term_beep(el);
559 			term__flush();
560 			break;
561 		}
562 		el->el_state.argument = 1;
563 		el->el_state.doingarg = 0;
564 		el->el_chared.c_vcmd.action = NOP;
565 	}
566 
567 	term__flush();		/* flush any buffered output */
568 	/* make sure the tty is set up correctly */
569 	(void) tty_cookedmode(el);
570 	if (el->el_flags & HANDLE_SIGNALS)
571 		sig_clr(el);
572 	if (nread)
573 		*nread = num;
574 	return (num ? el->el_line.buffer : NULL);
575 }
576