1/*	$NetBSD: read.c,v 1.70 2013/05/27 23:55:55 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
38static char sccsid[] = "@(#)read.c	8.1 (Berkeley) 6/4/93";
39#else
40__RCSID("$NetBSD: read.c,v 1.70 2013/05/27 23:55:55 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 <limits.h>
53#include "el.h"
54
55#define OKCMD	-1	/* must be -1! */
56
57private int	read__fixio(int, int);
58private int	read_preread(EditLine *);
59private int	read_char(EditLine *, Char *);
60private int	read_getcmd(EditLine *, el_action_t *, Char *);
61private void	read_pop(c_macro_t *);
62
63/* read_init():
64 *	Initialize the read stuff
65 */
66protected int
67read_init(EditLine *el)
68{
69	/* builtin read_char */
70	el->el_read.read_char = read_char;
71	return 0;
72}
73
74
75/* el_read_setfn():
76 *	Set the read char function to the one provided.
77 *	If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
78 */
79protected int
80el_read_setfn(EditLine *el, el_rfunc_t rc)
81{
82	el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
83	return 0;
84}
85
86
87/* el_read_getfn():
88 *	return the current read char function, or EL_BUILTIN_GETCFN
89 *	if it is the default one
90 */
91protected el_rfunc_t
92el_read_getfn(EditLine *el)
93{
94       return el->el_read.read_char == read_char ?
95	    EL_BUILTIN_GETCFN : el->el_read.read_char;
96}
97
98
99#ifndef MIN
100#define MIN(A,B) ((A) < (B) ? (A) : (B))
101#endif
102
103#ifdef DEBUG_EDIT
104private void
105read_debug(EditLine *el)
106{
107
108	if (el->el_line.cursor > el->el_line.lastchar)
109		(void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
110	if (el->el_line.cursor < el->el_line.buffer)
111		(void) fprintf(el->el_errfile, "cursor < buffer\r\n");
112	if (el->el_line.cursor > el->el_line.limit)
113		(void) fprintf(el->el_errfile, "cursor > limit\r\n");
114	if (el->el_line.lastchar > el->el_line.limit)
115		(void) fprintf(el->el_errfile, "lastchar > limit\r\n");
116	if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
117		(void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
118}
119#endif /* DEBUG_EDIT */
120
121
122/* read__fixio():
123 *	Try to recover from a read error
124 */
125/* ARGSUSED */
126private int
127read__fixio(int fd __attribute__((__unused__)), int e)
128{
129
130	switch (e) {
131	case -1:		/* Make sure that the code is reachable */
132
133#ifdef EWOULDBLOCK
134	case EWOULDBLOCK:
135#ifndef TRY_AGAIN
136#define TRY_AGAIN
137#endif
138#endif /* EWOULDBLOCK */
139
140#if defined(POSIX) && defined(EAGAIN)
141#if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
142	case EAGAIN:
143#ifndef TRY_AGAIN
144#define TRY_AGAIN
145#endif
146#endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
147#endif /* POSIX && EAGAIN */
148
149		e = 0;
150#ifdef TRY_AGAIN
151#if defined(F_SETFL) && defined(O_NDELAY)
152		if ((e = fcntl(fd, F_GETFL, 0)) == -1)
153			return -1;
154
155		if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
156			return -1;
157		else
158			e = 1;
159#endif /* F_SETFL && O_NDELAY */
160
161#ifdef FIONBIO
162		{
163			int zero = 0;
164
165			if (ioctl(fd, FIONBIO, &zero) == -1)
166				return -1;
167			else
168				e = 1;
169		}
170#endif /* FIONBIO */
171
172#endif /* TRY_AGAIN */
173		return e ? 0 : -1;
174
175	case EINTR:
176		return 0;
177
178	default:
179		return -1;
180	}
181}
182
183
184/* read_preread():
185 *	Try to read the stuff in the input queue;
186 */
187private int
188read_preread(EditLine *el)
189{
190	int chrs = 0;
191
192	if (el->el_tty.t_mode == ED_IO)
193		return 0;
194
195#ifndef WIDECHAR
196/* FIONREAD attempts to buffer up multiple bytes, and to make that work
197 * properly with partial wide/UTF-8 characters would need some careful work. */
198#ifdef FIONREAD
199	(void) ioctl(el->el_infd, FIONREAD, &chrs);
200	if (chrs > 0) {
201		char buf[EL_BUFSIZ];
202
203		chrs = read(el->el_infd, buf,
204		    (size_t) MIN(chrs, EL_BUFSIZ - 1));
205		if (chrs > 0) {
206			buf[chrs] = '\0';
207			el_push(el, buf);
208		}
209	}
210#endif /* FIONREAD */
211#endif
212	return chrs > 0;
213}
214
215
216/* el_push():
217 *	Push a macro
218 */
219public void
220FUN(el,push)(EditLine *el, const Char *str)
221{
222	c_macro_t *ma = &el->el_chared.c_macro;
223
224	if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
225		ma->level++;
226		if ((ma->macro[ma->level] = Strdup(str)) != NULL)
227			return;
228		ma->level--;
229	}
230	terminal_beep(el);
231	terminal__flush(el);
232}
233
234
235/* read_getcmd():
236 *	Get next command from the input stream, return OKCMD on success.
237 *	Character values > 255 are not looked up in the map, but inserted.
238 */
239private int
240read_getcmd(EditLine *el, el_action_t *cmdnum, Char *ch)
241{
242	el_action_t cmd;
243	int num;
244
245	el->el_errno = 0;
246	do {
247		if ((num = FUN(el,getc)(el, ch)) != 1) {/* if EOF or error */
248			el->el_errno = num == 0 ? 0 : errno;
249			return 0;	/* not OKCMD */
250		}
251
252#ifdef	KANJI
253		if ((*ch & 0200)) {
254			el->el_state.metanext = 0;
255			cmd = CcViMap[' '];
256			break;
257		} else
258#endif /* KANJI */
259
260		if (el->el_state.metanext) {
261			el->el_state.metanext = 0;
262			*ch |= 0200;
263		}
264#ifdef WIDECHAR
265		if (*ch >= N_KEYS)
266			cmd = ED_INSERT;
267		else
268#endif
269			cmd = el->el_map.current[(unsigned char) *ch];
270		if (cmd == ED_SEQUENCE_LEAD_IN) {
271			keymacro_value_t val;
272			switch (keymacro_get(el, ch, &val)) {
273			case XK_CMD:
274				cmd = val.cmd;
275				break;
276			case XK_STR:
277				FUN(el,push)(el, val.str);
278				break;
279#ifdef notyet
280			case XK_EXE:
281				/* XXX: In the future to run a user function */
282				RunCommand(val.str);
283				break;
284#endif
285			default:
286				EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
287				break;
288			}
289		}
290		if (el->el_map.alt == NULL)
291			el->el_map.current = el->el_map.key;
292	} while (cmd == ED_SEQUENCE_LEAD_IN);
293	*cmdnum = cmd;
294	return OKCMD;
295}
296
297#ifdef WIDECHAR
298/* utf8_islead():
299 *	Test whether a byte is a leading byte of a UTF-8 sequence.
300 */
301private int
302utf8_islead(int c)
303{
304	return c < 0x80 ||	       /* single byte char */
305	       (c >= 0xc2 && c <= 0xf4); /* start of multibyte sequence */
306}
307#endif
308
309/* read_char():
310 *	Read a character from the tty.
311 */
312private int
313read_char(EditLine *el, Char *cp)
314{
315	ssize_t num_read;
316	int tried = 0;
317	char cbuf[MB_LEN_MAX];
318	size_t cbp = 0;
319	int bytes = 0;
320
321 again:
322	el->el_signal->sig_no = 0;
323	while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
324		int e = errno;
325		switch (el->el_signal->sig_no) {
326		case SIGCONT:
327			FUN(el,set)(el, EL_REFRESH);
328			/*FALLTHROUGH*/
329		case SIGWINCH:
330			sig_set(el);
331			goto again;
332		default:
333			break;
334		}
335		if (!tried && read__fixio(el->el_infd, e) == 0)
336			tried = 1;
337		else {
338			errno = e;
339			*cp = '\0';
340			return -1;
341		}
342	}
343
344	/* Test for EOF */
345	if (num_read == 0) {
346		errno = 0;
347		*cp = '\0';
348		return 0;
349	}
350
351#ifdef WIDECHAR
352	if (el->el_flags & CHARSET_IS_UTF8) {
353		if (!utf8_islead((unsigned char)cbuf[0]))
354			goto again; /* discard the byte we read and try again */
355		++cbp;
356		if ((bytes = ct_mbtowc(cp, cbuf, cbp)) == -1) {
357			ct_mbtowc_reset;
358			if (cbp >= MB_LEN_MAX) { /* "shouldn't happen" */
359				errno = EILSEQ;
360				*cp = '\0';
361				return -1;
362			}
363			goto again;
364		}
365	} else if (isascii((unsigned char)cbuf[0]) ||
366		/* we don't support other multibyte charsets */
367		++cbp != 1 ||
368		/* Try non-ASCII characters in a 8-bit character set */
369		(bytes = ct_mbtowc(cp, cbuf, cbp)) != 1)
370#endif
371		*cp = (unsigned char)cbuf[0];
372
373	if ((el->el_flags & IGNORE_EXTCHARS) && bytes > 1) {
374		cbp = 0; /* skip this character */
375		goto again;
376	}
377
378	return (int)num_read;
379}
380
381/* read_pop():
382 *	Pop a macro from the stack
383 */
384private void
385read_pop(c_macro_t *ma)
386{
387	int i;
388
389	el_free(ma->macro[0]);
390	for (i = 0; i < ma->level; i++)
391		ma->macro[i] = ma->macro[i + 1];
392	ma->level--;
393	ma->offset = 0;
394}
395
396/* el_getc():
397 *	Read a character
398 */
399public int
400FUN(el,getc)(EditLine *el, Char *cp)
401{
402	int num_read;
403	c_macro_t *ma = &el->el_chared.c_macro;
404
405	terminal__flush(el);
406	for (;;) {
407		if (ma->level < 0) {
408			if (!read_preread(el))
409				break;
410		}
411
412		if (ma->level < 0)
413			break;
414
415		if (ma->macro[0][ma->offset] == '\0') {
416			read_pop(ma);
417			continue;
418		}
419
420		*cp = ma->macro[0][ma->offset++];
421
422		if (ma->macro[0][ma->offset] == '\0') {
423			/* Needed for QuoteMode On */
424			read_pop(ma);
425		}
426
427		return 1;
428	}
429
430#ifdef DEBUG_READ
431	(void) fprintf(el->el_errfile, "Turning raw mode on\n");
432#endif /* DEBUG_READ */
433	if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
434		return 0;
435
436#ifdef DEBUG_READ
437	(void) fprintf(el->el_errfile, "Reading a character\n");
438#endif /* DEBUG_READ */
439	num_read = (*el->el_read.read_char)(el, cp);
440	if (num_read < 0)
441		el->el_errno = errno;
442#ifdef WIDECHAR
443	if (el->el_flags & NARROW_READ)
444		*cp = *(char *)(void *)cp;
445#endif
446#ifdef DEBUG_READ
447	(void) fprintf(el->el_errfile, "Got it %c\n", *cp);
448#endif /* DEBUG_READ */
449	return num_read;
450}
451
452protected void
453read_prepare(EditLine *el)
454{
455	if (el->el_flags & HANDLE_SIGNALS)
456		sig_set(el);
457	if (el->el_flags & NO_TTY)
458		return;
459	if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
460		tty_rawmode(el);
461
462	/* This is relatively cheap, and things go terribly wrong if
463	   we have the wrong size. */
464	el_resize(el);
465	re_clear_display(el);	/* reset the display stuff */
466	ch_reset(el, 0);
467	re_refresh(el);		/* print the prompt */
468
469	if (el->el_flags & UNBUFFERED)
470		terminal__flush(el);
471}
472
473protected void
474read_finish(EditLine *el)
475{
476	if ((el->el_flags & UNBUFFERED) == 0)
477		(void) tty_cookedmode(el);
478	if (el->el_flags & HANDLE_SIGNALS)
479		sig_clr(el);
480}
481
482public const Char *
483FUN(el,gets)(EditLine *el, int *nread)
484{
485	int retval;
486	el_action_t cmdnum = 0;
487	int num;		/* how many chars we have read at NL */
488	Char ch, *cp;
489	int crlf = 0;
490	int nrb;
491#ifdef FIONREAD
492	c_macro_t *ma = &el->el_chared.c_macro;
493#endif /* FIONREAD */
494
495	if (nread == NULL)
496		nread = &nrb;
497	*nread = 0;
498
499	if (el->el_flags & NO_TTY) {
500		size_t idx;
501
502		cp = el->el_line.buffer;
503		while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
504			/* make sure there is space for next character */
505			if (cp + 1 >= el->el_line.limit) {
506				idx = (size_t)(cp - el->el_line.buffer);
507				if (!ch_enlargebufs(el, (size_t)2))
508					break;
509				cp = &el->el_line.buffer[idx];
510			}
511			cp++;
512			if (el->el_flags & UNBUFFERED)
513				break;
514			if (cp[-1] == '\r' || cp[-1] == '\n')
515				break;
516		}
517		if (num == -1) {
518			if (errno == EINTR)
519				cp = el->el_line.buffer;
520			el->el_errno = errno;
521		}
522
523		goto noedit;
524	}
525
526
527#ifdef FIONREAD
528	if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
529		long chrs = 0;
530
531		(void) ioctl(el->el_infd, FIONREAD, &chrs);
532		if (chrs == 0) {
533			if (tty_rawmode(el) < 0) {
534				errno = 0;
535				*nread = 0;
536				return NULL;
537			}
538		}
539	}
540#endif /* FIONREAD */
541
542	if ((el->el_flags & UNBUFFERED) == 0)
543		read_prepare(el);
544
545	if (el->el_flags & EDIT_DISABLED) {
546		size_t idx;
547
548		if ((el->el_flags & UNBUFFERED) == 0)
549			cp = el->el_line.buffer;
550		else
551			cp = el->el_line.lastchar;
552
553		terminal__flush(el);
554
555		while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
556			/* make sure there is space next character */
557			if (cp + 1 >= el->el_line.limit) {
558				idx = (size_t)(cp - el->el_line.buffer);
559				if (!ch_enlargebufs(el, (size_t)2))
560					break;
561				cp = &el->el_line.buffer[idx];
562			}
563			cp++;
564			crlf = cp[-1] == '\r' || cp[-1] == '\n';
565			if (el->el_flags & UNBUFFERED)
566				break;
567			if (crlf)
568				break;
569		}
570
571		if (num == -1) {
572			if (errno == EINTR)
573				cp = el->el_line.buffer;
574			el->el_errno = errno;
575		}
576
577		goto noedit;
578	}
579
580	for (num = OKCMD; num == OKCMD;) {	/* while still editing this
581						 * line */
582#ifdef DEBUG_EDIT
583		read_debug(el);
584#endif /* DEBUG_EDIT */
585		/* if EOF or error */
586		if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
587			num = -1;
588#ifdef DEBUG_READ
589			(void) fprintf(el->el_errfile,
590			    "Returning from el_gets %d\n", num);
591#endif /* DEBUG_READ */
592			break;
593		}
594		if (el->el_errno == EINTR) {
595			el->el_line.buffer[0] = '\0';
596			el->el_line.lastchar =
597			    el->el_line.cursor = el->el_line.buffer;
598			break;
599		}
600		if ((unsigned int)cmdnum >= (unsigned int)el->el_map.nfunc) {	/* BUG CHECK command */
601#ifdef DEBUG_EDIT
602			(void) fprintf(el->el_errfile,
603			    "ERROR: illegal command from key 0%o\r\n", ch);
604#endif /* DEBUG_EDIT */
605			continue;	/* try again */
606		}
607		/* now do the real command */
608#ifdef DEBUG_READ
609		{
610			el_bindings_t *b;
611			for (b = el->el_map.help; b->name; b++)
612				if (b->func == cmdnum)
613					break;
614			if (b->name)
615				(void) fprintf(el->el_errfile,
616				    "Executing %s\n", b->name);
617			else
618				(void) fprintf(el->el_errfile,
619				    "Error command = %d\n", cmdnum);
620		}
621#endif /* DEBUG_READ */
622		/* vi redo needs these way down the levels... */
623		el->el_state.thiscmd = cmdnum;
624		el->el_state.thisch = ch;
625		if (el->el_map.type == MAP_VI &&
626		    el->el_map.current == el->el_map.key &&
627		    el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
628			if (cmdnum == VI_DELETE_PREV_CHAR &&
629			    el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
630			    && Isprint(el->el_chared.c_redo.pos[-1]))
631				el->el_chared.c_redo.pos--;
632			else
633				*el->el_chared.c_redo.pos++ = ch;
634		}
635		retval = (*el->el_map.func[cmdnum]) (el, ch);
636#ifdef DEBUG_READ
637		(void) fprintf(el->el_errfile,
638			"Returned state %d\n", retval );
639#endif /* DEBUG_READ */
640
641		/* save the last command here */
642		el->el_state.lastcmd = cmdnum;
643
644		/* use any return value */
645		switch (retval) {
646		case CC_CURSOR:
647			re_refresh_cursor(el);
648			break;
649
650		case CC_REDISPLAY:
651			re_clear_lines(el);
652			re_clear_display(el);
653			/* FALLTHROUGH */
654
655		case CC_REFRESH:
656			re_refresh(el);
657			break;
658
659		case CC_REFRESH_BEEP:
660			re_refresh(el);
661			terminal_beep(el);
662			break;
663
664		case CC_NORM:	/* normal char */
665			break;
666
667		case CC_ARGHACK:	/* Suggested by Rich Salz */
668			/* <rsalz@pineapple.bbn.com> */
669			continue;	/* keep going... */
670
671		case CC_EOF:	/* end of file typed */
672			if ((el->el_flags & UNBUFFERED) == 0)
673				num = 0;
674			else if (num == -1) {
675				*el->el_line.lastchar++ = CONTROL('d');
676				el->el_line.cursor = el->el_line.lastchar;
677				num = 1;
678			}
679			break;
680
681		case CC_NEWLINE:	/* normal end of line */
682			num = (int)(el->el_line.lastchar - el->el_line.buffer);
683			break;
684
685		case CC_FATAL:	/* fatal error, reset to known state */
686#ifdef DEBUG_READ
687			(void) fprintf(el->el_errfile,
688			    "*** editor fatal ERROR ***\r\n\n");
689#endif /* DEBUG_READ */
690			/* put (real) cursor in a known place */
691			re_clear_display(el);	/* reset the display stuff */
692			ch_reset(el, 1);	/* reset the input pointers */
693			re_refresh(el); /* print the prompt again */
694			break;
695
696		case CC_ERROR:
697		default:	/* functions we don't know about */
698#ifdef DEBUG_READ
699			(void) fprintf(el->el_errfile,
700			    "*** editor ERROR ***\r\n\n");
701#endif /* DEBUG_READ */
702			terminal_beep(el);
703			terminal__flush(el);
704			break;
705		}
706		el->el_state.argument = 1;
707		el->el_state.doingarg = 0;
708		el->el_chared.c_vcmd.action = NOP;
709		if (el->el_flags & UNBUFFERED)
710			break;
711	}
712
713	terminal__flush(el);		/* flush any buffered output */
714	/* make sure the tty is set up correctly */
715	if ((el->el_flags & UNBUFFERED) == 0) {
716		read_finish(el);
717		*nread = num != -1 ? num : 0;
718	} else {
719		*nread = (int)(el->el_line.lastchar - el->el_line.buffer);
720	}
721	goto done;
722noedit:
723	el->el_line.cursor = el->el_line.lastchar = cp;
724	*cp = '\0';
725	*nread = (int)(el->el_line.cursor - el->el_line.buffer);
726done:
727	if (*nread == 0) {
728		if (num == -1) {
729			*nread = -1;
730			errno = el->el_errno;
731		}
732		return NULL;
733	} else
734		return el->el_line.buffer;
735}
736