1 /* $NetBSD: read.c,v 1.107 2021/08/15 10:08:41 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 1.107 2021/08/15 10:08:41 christos Exp $");
41 #endif
42 #endif /* not lint && not SCCSID */
43
44 /*
45 * read.c: Terminal read functions
46 */
47 #include <ctype.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <limits.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54
55 #include "el.h"
56 #include "fcns.h"
57 #include "read.h"
58
59 #define EL_MAXMACRO 10
60
61 struct macros {
62 wchar_t **macro;
63 int level;
64 int offset;
65 };
66
67 struct el_read_t {
68 struct macros macros;
69 el_rfunc_t read_char; /* Function to read a character. */
70 int read_errno;
71 };
72
73 static int read__fixio(int, int);
74 static int read_char(EditLine *, wchar_t *);
75 static int read_getcmd(EditLine *, el_action_t *, wchar_t *);
76 static void read_clearmacros(struct macros *);
77 static void read_pop(struct macros *);
78 static const wchar_t *noedit_wgets(EditLine *, int *);
79
80 /* read_init():
81 * Initialize the read stuff
82 */
83 libedit_private int
read_init(EditLine * el)84 read_init(EditLine *el)
85 {
86 struct macros *ma;
87
88 if ((el->el_read = el_malloc(sizeof(*el->el_read))) == NULL)
89 return -1;
90
91 ma = &el->el_read->macros;
92 if ((ma->macro = el_calloc(EL_MAXMACRO, sizeof(*ma->macro))) == NULL) {
93 free(el->el_read);
94 return -1;
95 }
96 ma->level = -1;
97 ma->offset = 0;
98
99 /* builtin read_char */
100 el->el_read->read_char = read_char;
101 return 0;
102 }
103
104 /* el_read_end():
105 * Free the data structures used by the read stuff.
106 */
107 libedit_private void
read_end(struct el_read_t * el_read)108 read_end(struct el_read_t *el_read)
109 {
110 read_clearmacros(&el_read->macros);
111 el_free(el_read->macros.macro);
112 el_read->macros.macro = NULL;
113 el_free(el_read);
114 }
115
116 /* el_read_setfn():
117 * Set the read char function to the one provided.
118 * If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
119 */
120 libedit_private int
el_read_setfn(struct el_read_t * el_read,el_rfunc_t rc)121 el_read_setfn(struct el_read_t *el_read, el_rfunc_t rc)
122 {
123 el_read->read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
124 return 0;
125 }
126
127
128 /* el_read_getfn():
129 * return the current read char function, or EL_BUILTIN_GETCFN
130 * if it is the default one
131 */
132 libedit_private el_rfunc_t
el_read_getfn(struct el_read_t * el_read)133 el_read_getfn(struct el_read_t *el_read)
134 {
135 return el_read->read_char == read_char ?
136 EL_BUILTIN_GETCFN : el_read->read_char;
137 }
138
139
140 /* read__fixio():
141 * Try to recover from a read error
142 */
143 /* ARGSUSED */
144 static int
read__fixio(int fd,int e)145 read__fixio(int fd __attribute__((__unused__)), int e)
146 {
147
148 switch (e) {
149 case -1: /* Make sure that the code is reachable */
150
151 #ifdef EWOULDBLOCK
152 case EWOULDBLOCK:
153 #ifndef TRY_AGAIN
154 #define TRY_AGAIN
155 #endif
156 #endif /* EWOULDBLOCK */
157
158 #if defined(POSIX) && defined(EAGAIN)
159 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
160 case EAGAIN:
161 #ifndef TRY_AGAIN
162 #define TRY_AGAIN
163 #endif
164 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
165 #endif /* POSIX && EAGAIN */
166
167 e = 0;
168 #ifdef TRY_AGAIN
169 #if defined(F_SETFL) && defined(O_NDELAY)
170 if ((e = fcntl(fd, F_GETFL, 0)) == -1)
171 return -1;
172
173 if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
174 return -1;
175 else
176 e = 1;
177 #endif /* F_SETFL && O_NDELAY */
178
179 #ifdef FIONBIO
180 {
181 int zero = 0;
182
183 if (ioctl(fd, FIONBIO, &zero) == -1)
184 return -1;
185 else
186 e = 1;
187 }
188 #endif /* FIONBIO */
189
190 #endif /* TRY_AGAIN */
191 return e ? 0 : -1;
192
193 case EINTR:
194 return 0;
195
196 default:
197 return -1;
198 }
199 }
200
201
202 /* el_push():
203 * Push a macro
204 */
205 void
el_wpush(EditLine * el,const wchar_t * str)206 el_wpush(EditLine *el, const wchar_t *str)
207 {
208 struct macros *ma = &el->el_read->macros;
209
210 if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
211 ma->level++;
212 if ((ma->macro[ma->level] = wcsdup(str)) != NULL)
213 return;
214 ma->level--;
215 }
216 terminal_beep(el);
217 terminal__flush(el);
218 }
219
220
221 /* read_getcmd():
222 * Get next command from the input stream,
223 * return 0 on success or -1 on EOF or error.
224 * Character values > 255 are not looked up in the map, but inserted.
225 */
226 static int
read_getcmd(EditLine * el,el_action_t * cmdnum,wchar_t * ch)227 read_getcmd(EditLine *el, el_action_t *cmdnum, wchar_t *ch)
228 {
229 static const wchar_t meta = (wchar_t)0x80;
230 el_action_t cmd;
231
232 do {
233 if (el_wgetc(el, ch) != 1)
234 return -1;
235
236 #ifdef KANJI
237 if ((*ch & meta)) {
238 el->el_state.metanext = 0;
239 cmd = CcViMap[' '];
240 break;
241 } else
242 #endif /* KANJI */
243
244 if (el->el_state.metanext) {
245 el->el_state.metanext = 0;
246 *ch |= meta;
247 }
248 if (*ch >= N_KEYS)
249 cmd = ED_INSERT;
250 else
251 cmd = el->el_map.current[(unsigned char) *ch];
252 if (cmd == ED_SEQUENCE_LEAD_IN) {
253 keymacro_value_t val;
254 switch (keymacro_get(el, ch, &val)) {
255 case XK_CMD:
256 cmd = val.cmd;
257 break;
258 case XK_STR:
259 el_wpush(el, val.str);
260 break;
261 case XK_NOD:
262 return -1;
263 default:
264 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
265 break;
266 }
267 }
268 } while (cmd == ED_SEQUENCE_LEAD_IN);
269 *cmdnum = cmd;
270 return 0;
271 }
272
273 /* read_char():
274 * Read a character from the tty.
275 */
276 static int
read_char(EditLine * el,wchar_t * cp)277 read_char(EditLine *el, wchar_t *cp)
278 {
279 ssize_t num_read;
280 int tried = (el->el_flags & FIXIO) == 0;
281 char cbuf[MB_LEN_MAX];
282 size_t cbp = 0;
283 int save_errno = errno;
284
285 again:
286 el->el_signal->sig_no = 0;
287 while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
288 int e = errno;
289 switch (el->el_signal->sig_no) {
290 case SIGCONT:
291 el_wset(el, EL_REFRESH);
292 /*FALLTHROUGH*/
293 case SIGWINCH:
294 sig_set(el);
295 goto again;
296 default:
297 break;
298 }
299 if (!tried && read__fixio(el->el_infd, e) == 0) {
300 errno = save_errno;
301 tried = 1;
302 } else {
303 errno = e;
304 *cp = L'\0';
305 return -1;
306 }
307 }
308
309 /* Test for EOF */
310 if (num_read == 0) {
311 *cp = L'\0';
312 return 0;
313 }
314
315 for (;;) {
316 mbstate_t mbs;
317
318 ++cbp;
319 /* This only works because UTF8 is stateless. */
320 memset(&mbs, 0, sizeof(mbs));
321 switch (mbrtowc(cp, cbuf, cbp, &mbs)) {
322 case (size_t)-1:
323 if (cbp > 1) {
324 /*
325 * Invalid sequence, discard all bytes
326 * except the last one.
327 */
328 cbuf[0] = cbuf[cbp - 1];
329 cbp = 0;
330 break;
331 } else {
332 /* Invalid byte, discard it. */
333 cbp = 0;
334 goto again;
335 }
336 case (size_t)-2:
337 if (cbp >= MB_LEN_MAX) {
338 errno = EILSEQ;
339 *cp = L'\0';
340 return -1;
341 }
342 /* Incomplete sequence, read another byte. */
343 goto again;
344 default:
345 /* Valid character, process it. */
346 return 1;
347 }
348 }
349 }
350
351 /* read_pop():
352 * Pop a macro from the stack
353 */
354 static void
read_pop(struct macros * ma)355 read_pop(struct macros *ma)
356 {
357 int i;
358
359 el_free(ma->macro[0]);
360 for (i = 0; i < ma->level; i++)
361 ma->macro[i] = ma->macro[i + 1];
362 ma->level--;
363 ma->offset = 0;
364 }
365
366 static void
read_clearmacros(struct macros * ma)367 read_clearmacros(struct macros *ma)
368 {
369 while (ma->level >= 0)
370 el_free(ma->macro[ma->level--]);
371 ma->offset = 0;
372 }
373
374 /* el_wgetc():
375 * Read a wide character
376 */
377 int
el_wgetc(EditLine * el,wchar_t * cp)378 el_wgetc(EditLine *el, wchar_t *cp)
379 {
380 struct macros *ma = &el->el_read->macros;
381 int num_read;
382
383 terminal__flush(el);
384 for (;;) {
385 if (ma->level < 0)
386 break;
387
388 if (ma->macro[0][ma->offset] == '\0') {
389 read_pop(ma);
390 continue;
391 }
392
393 *cp = ma->macro[0][ma->offset++];
394
395 if (ma->macro[0][ma->offset] == '\0') {
396 /* Needed for QuoteMode On */
397 read_pop(ma);
398 }
399
400 return 1;
401 }
402
403 if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
404 return 0;
405
406 num_read = (*el->el_read->read_char)(el, cp);
407
408 /*
409 * Remember the original reason of a read failure
410 * such that el_wgets() can restore it after doing
411 * various cleanup operation that might change errno.
412 */
413 if (num_read < 0)
414 el->el_read->read_errno = errno;
415
416 return num_read;
417 }
418
419 libedit_private void
read_prepare(EditLine * el)420 read_prepare(EditLine *el)
421 {
422 if (el->el_flags & HANDLE_SIGNALS)
423 sig_set(el);
424 if (el->el_flags & NO_TTY)
425 return;
426 if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
427 tty_rawmode(el);
428
429 /* This is relatively cheap, and things go terribly wrong if
430 we have the wrong size. */
431 el_resize(el);
432 re_clear_display(el); /* reset the display stuff */
433 ch_reset(el);
434 re_refresh(el); /* print the prompt */
435
436 if (el->el_flags & UNBUFFERED)
437 terminal__flush(el);
438 }
439
440 libedit_private void
read_finish(EditLine * el)441 read_finish(EditLine *el)
442 {
443 if ((el->el_flags & UNBUFFERED) == 0)
444 (void) tty_cookedmode(el);
445 if (el->el_flags & HANDLE_SIGNALS)
446 sig_clr(el);
447 }
448
449 static const wchar_t *
noedit_wgets(EditLine * el,int * nread)450 noedit_wgets(EditLine *el, int *nread)
451 {
452 el_line_t *lp = &el->el_line;
453 int num;
454
455 while ((num = (*el->el_read->read_char)(el, lp->lastchar)) == 1) {
456 if (lp->lastchar + 1 >= lp->limit &&
457 !ch_enlargebufs(el, (size_t)2))
458 break;
459 lp->lastchar++;
460 if (el->el_flags & UNBUFFERED ||
461 lp->lastchar[-1] == '\r' ||
462 lp->lastchar[-1] == '\n')
463 break;
464 }
465 if (num == -1 && errno == EINTR)
466 lp->lastchar = lp->buffer;
467 lp->cursor = lp->lastchar;
468 *lp->lastchar = '\0';
469 *nread = (int)(lp->lastchar - lp->buffer);
470 return *nread ? lp->buffer : NULL;
471 }
472
473 const wchar_t *
el_wgets(EditLine * el,int * nread)474 el_wgets(EditLine *el, int *nread)
475 {
476 int retval;
477 el_action_t cmdnum = 0;
478 int num; /* how many chars we have read at NL */
479 wchar_t ch;
480 int nrb;
481
482 if (nread == NULL)
483 nread = &nrb;
484 *nread = 0;
485 el->el_read->read_errno = 0;
486
487 if (el->el_flags & NO_TTY) {
488 el->el_line.lastchar = el->el_line.buffer;
489 return noedit_wgets(el, nread);
490 }
491
492 #ifdef FIONREAD
493 if (el->el_tty.t_mode == EX_IO && el->el_read->macros.level < 0) {
494 int chrs = 0;
495
496 (void) ioctl(el->el_infd, FIONREAD, &chrs);
497 if (chrs == 0) {
498 if (tty_rawmode(el) < 0) {
499 errno = 0;
500 *nread = 0;
501 return NULL;
502 }
503 }
504 }
505 #endif /* FIONREAD */
506
507 if ((el->el_flags & UNBUFFERED) == 0)
508 read_prepare(el);
509
510 if (el->el_flags & EDIT_DISABLED) {
511 if ((el->el_flags & UNBUFFERED) == 0)
512 el->el_line.lastchar = el->el_line.buffer;
513 terminal__flush(el);
514 return noedit_wgets(el, nread);
515 }
516
517 for (num = -1; num == -1;) { /* while still editing this line */
518 /* if EOF or error */
519 if (read_getcmd(el, &cmdnum, &ch) == -1)
520 break;
521 if ((size_t)cmdnum >= el->el_map.nfunc) /* BUG CHECK command */
522 continue; /* try again */
523 /* now do the real command */
524 /* vi redo needs these way down the levels... */
525 el->el_state.thiscmd = cmdnum;
526 el->el_state.thisch = ch;
527 if (el->el_map.type == MAP_VI &&
528 el->el_map.current == el->el_map.key &&
529 el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
530 if (cmdnum == VI_DELETE_PREV_CHAR &&
531 el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
532 && iswprint(el->el_chared.c_redo.pos[-1]))
533 el->el_chared.c_redo.pos--;
534 else
535 *el->el_chared.c_redo.pos++ = ch;
536 }
537 retval = (*el->el_map.func[cmdnum]) (el, ch);
538
539 /* save the last command here */
540 el->el_state.lastcmd = cmdnum;
541
542 /* use any return value */
543 switch (retval) {
544 case CC_CURSOR:
545 re_refresh_cursor(el);
546 break;
547
548 case CC_REDISPLAY:
549 re_clear_lines(el);
550 re_clear_display(el);
551 /* FALLTHROUGH */
552
553 case CC_REFRESH:
554 re_refresh(el);
555 break;
556
557 case CC_REFRESH_BEEP:
558 re_refresh(el);
559 terminal_beep(el);
560 break;
561
562 case CC_NORM: /* normal char */
563 break;
564
565 case CC_ARGHACK: /* Suggested by Rich Salz */
566 /* <rsalz@pineapple.bbn.com> */
567 continue; /* keep going... */
568
569 case CC_EOF: /* end of file typed */
570 if ((el->el_flags & UNBUFFERED) == 0)
571 num = 0;
572 else if (num == -1) {
573 *el->el_line.lastchar++ = CONTROL('d');
574 el->el_line.cursor = el->el_line.lastchar;
575 num = 1;
576 }
577 break;
578
579 case CC_NEWLINE: /* normal end of line */
580 num = (int)(el->el_line.lastchar - el->el_line.buffer);
581 break;
582
583 case CC_FATAL: /* fatal error, reset to known state */
584 /* put (real) cursor in a known place */
585 re_clear_display(el); /* reset the display stuff */
586 ch_reset(el); /* reset the input pointers */
587 read_clearmacros(&el->el_read->macros);
588 re_refresh(el); /* print the prompt again */
589 break;
590
591 case CC_ERROR:
592 default: /* functions we don't know about */
593 terminal_beep(el);
594 terminal__flush(el);
595 break;
596 }
597 el->el_state.argument = 1;
598 el->el_state.doingarg = 0;
599 el->el_chared.c_vcmd.action = NOP;
600 if (el->el_flags & UNBUFFERED)
601 break;
602 }
603
604 terminal__flush(el); /* flush any buffered output */
605 /* make sure the tty is set up correctly */
606 if ((el->el_flags & UNBUFFERED) == 0) {
607 read_finish(el);
608 *nread = num != -1 ? num : 0;
609 } else
610 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
611
612 if (*nread == 0) {
613 if (num == -1) {
614 *nread = -1;
615 if (el->el_read->read_errno)
616 errno = el->el_read->read_errno;
617 }
618 return NULL;
619 } else
620 return el->el_line.buffer;
621 }
622