Home | History | Annotate | Line # | Download | only in libedit
read.c revision 1.102 
      1 /*	$NetBSD: read.c,v 1.102 2016/12/11 15:47:06 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. 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 1.102 2016/12/11 15:47:06 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
     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_malloc(EL_MAXMACRO *
     93 	    sizeof(*ma->macro))) == NULL) {
     94 		free(el->el_read);
     95 		return -1;
     96 	}
     97 	ma->level = -1;
     98 	ma->offset = 0;
     99 
    100 	/* builtin read_char */
    101 	el->el_read->read_char = read_char;
    102 	return 0;
    103 }
    104 
    105 /* el_read_end():
    106  *	Free the data structures used by the read stuff.
    107  */
    108 libedit_private void
    109 read_end(struct el_read_t *el_read)
    110 {
    111 	read_clearmacros(&el_read->macros);
    112 	el_free(el_read->macros.macro);
    113 	el_read->macros.macro = NULL;
    114 	el_free(el_read);
    115 }
    116 
    117 /* el_read_setfn():
    118  *	Set the read char function to the one provided.
    119  *	If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
    120  */
    121 libedit_private int
    122 el_read_setfn(struct el_read_t *el_read, el_rfunc_t rc)
    123 {
    124 	el_read->read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
    125 	return 0;
    126 }
    127 
    128 
    129 /* el_read_getfn():
    130  *	return the current read char function, or EL_BUILTIN_GETCFN
    131  *	if it is the default one
    132  */
    133 libedit_private el_rfunc_t
    134 el_read_getfn(struct el_read_t *el_read)
    135 {
    136        return el_read->read_char == read_char ?
    137 	    EL_BUILTIN_GETCFN : el_read->read_char;
    138 }
    139 
    140 
    141 /* read__fixio():
    142  *	Try to recover from a read error
    143  */
    144 /* ARGSUSED */
    145 static int
    146 read__fixio(int fd __attribute__((__unused__)), int e)
    147 {
    148 
    149 	switch (e) {
    150 	case -1:		/* Make sure that the code is reachable */
    151 
    152 #ifdef EWOULDBLOCK
    153 	case EWOULDBLOCK:
    154 #ifndef TRY_AGAIN
    155 #define TRY_AGAIN
    156 #endif
    157 #endif /* EWOULDBLOCK */
    158 
    159 #if defined(POSIX) && defined(EAGAIN)
    160 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
    161 	case EAGAIN:
    162 #ifndef TRY_AGAIN
    163 #define TRY_AGAIN
    164 #endif
    165 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
    166 #endif /* POSIX && EAGAIN */
    167 
    168 		e = 0;
    169 #ifdef TRY_AGAIN
    170 #if defined(F_SETFL) && defined(O_NDELAY)
    171 		if ((e = fcntl(fd, F_GETFL, 0)) == -1)
    172 			return -1;
    173 
    174 		if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
    175 			return -1;
    176 		else
    177 			e = 1;
    178 #endif /* F_SETFL && O_NDELAY */
    179 
    180 #ifdef FIONBIO
    181 		{
    182 			int zero = 0;
    183 
    184 			if (ioctl(fd, FIONBIO, &zero) == -1)
    185 				return -1;
    186 			else
    187 				e = 1;
    188 		}
    189 #endif /* FIONBIO */
    190 
    191 #endif /* TRY_AGAIN */
    192 		return e ? 0 : -1;
    193 
    194 	case EINTR:
    195 		return 0;
    196 
    197 	default:
    198 		return -1;
    199 	}
    200 }
    201 
    202 
    203 /* el_push():
    204  *	Push a macro
    205  */
    206 void
    207 el_wpush(EditLine *el, const wchar_t *str)
    208 {
    209 	struct macros *ma = &el->el_read->macros;
    210 
    211 	if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
    212 		ma->level++;
    213 		if ((ma->macro[ma->level] = wcsdup(str)) != NULL)
    214 			return;
    215 		ma->level--;
    216 	}
    217 	terminal_beep(el);
    218 	terminal__flush(el);
    219 }
    220 
    221 
    222 /* read_getcmd():
    223  *	Get next command from the input stream,
    224  *	return 0 on success or -1 on EOF or error.
    225  *	Character values > 255 are not looked up in the map, but inserted.
    226  */
    227 static int
    228 read_getcmd(EditLine *el, el_action_t *cmdnum, wchar_t *ch)
    229 {
    230 	static const wchar_t meta = (wchar_t)0x80;
    231 	el_action_t cmd;
    232 	int num;
    233 
    234 	do {
    235 		if ((num = el_wgetc(el, ch)) != 1)
    236 			return -1;
    237 
    238 #ifdef	KANJI
    239 		if ((*ch & meta)) {
    240 			el->el_state.metanext = 0;
    241 			cmd = CcViMap[' '];
    242 			break;
    243 		} else
    244 #endif /* KANJI */
    245 
    246 		if (el->el_state.metanext) {
    247 			el->el_state.metanext = 0;
    248 			*ch |= meta;
    249 		}
    250 		if (*ch >= N_KEYS)
    251 			cmd = ED_INSERT;
    252 		else
    253 			cmd = el->el_map.current[(unsigned char) *ch];
    254 		if (cmd == ED_SEQUENCE_LEAD_IN) {
    255 			keymacro_value_t val;
    256 			switch (keymacro_get(el, ch, &val)) {
    257 			case XK_CMD:
    258 				cmd = val.cmd;
    259 				break;
    260 			case XK_STR:
    261 				el_wpush(el, val.str);
    262 				break;
    263 			case XK_NOD:
    264 				return -1;
    265 			default:
    266 				EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
    267 				break;
    268 			}
    269 		}
    270 	} while (cmd == ED_SEQUENCE_LEAD_IN);
    271 	*cmdnum = cmd;
    272 	return 0;
    273 }
    274 
    275 /* read_char():
    276  *	Read a character from the tty.
    277  */
    278 static int
    279 read_char(EditLine *el, wchar_t *cp)
    280 {
    281 	ssize_t num_read;
    282 	int tried = 0;
    283 	char cbuf[MB_LEN_MAX];
    284 	size_t cbp = 0;
    285 	int save_errno = errno;
    286 
    287  again:
    288 	el->el_signal->sig_no = 0;
    289 	while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
    290 		int e = errno;
    291 		switch (el->el_signal->sig_no) {
    292 		case SIGCONT:
    293 			el_wset(el, EL_REFRESH);
    294 			/*FALLTHROUGH*/
    295 		case SIGWINCH:
    296 			sig_set(el);
    297 			goto again;
    298 		default:
    299 			break;
    300 		}
    301 		if (!tried && read__fixio(el->el_infd, e) == 0) {
    302 			errno = save_errno;
    303 			tried = 1;
    304 		} else {
    305 			errno = e;
    306 			*cp = L'\0';
    307 			return -1;
    308 		}
    309 	}
    310 
    311 	/* Test for EOF */
    312 	if (num_read == 0) {
    313 		*cp = L'\0';
    314 		return 0;
    315 	}
    316 
    317 	for (;;) {
    318 		mbstate_t mbs;
    319 
    320 		++cbp;
    321 		/* This only works because UTF8 is stateless. */
    322 		memset(&mbs, 0, sizeof(mbs));
    323 		switch (mbrtowc(cp, cbuf, cbp, &mbs)) {
    324 		case (size_t)-1:
    325 			if (cbp > 1) {
    326 				/*
    327 				 * Invalid sequence, discard all bytes
    328 				 * except the last one.
    329 				 */
    330 				cbuf[0] = cbuf[cbp - 1];
    331 				cbp = 0;
    332 				break;
    333 			} else {
    334 				/* Invalid byte, discard it. */
    335 				cbp = 0;
    336 				goto again;
    337 			}
    338 		case (size_t)-2:
    339 			/*
    340 			 * We don't support other multibyte charsets.
    341 			 * The second condition shouldn't happen
    342 			 * and is here merely for additional safety.
    343 			 */
    344 			if ((el->el_flags & CHARSET_IS_UTF8) == 0 ||
    345 			    cbp >= MB_LEN_MAX) {
    346 				errno = EILSEQ;
    347 				*cp = L'\0';
    348 				return -1;
    349 			}
    350 			/* Incomplete sequence, read another byte. */
    351 			goto again;
    352 		default:
    353 			/* Valid character, process it. */
    354 			return 1;
    355 		}
    356 	}
    357 }
    358 
    359 /* read_pop():
    360  *	Pop a macro from the stack
    361  */
    362 static void
    363 read_pop(struct macros *ma)
    364 {
    365 	int i;
    366 
    367 	el_free(ma->macro[0]);
    368 	for (i = 0; i < ma->level; i++)
    369 		ma->macro[i] = ma->macro[i + 1];
    370 	ma->level--;
    371 	ma->offset = 0;
    372 }
    373 
    374 static void
    375 read_clearmacros(struct macros *ma)
    376 {
    377 	while (ma->level >= 0)
    378 		el_free(ma->macro[ma->level--]);
    379 	ma->offset = 0;
    380 }
    381 
    382 /* el_wgetc():
    383  *	Read a wide character
    384  */
    385 int
    386 el_wgetc(EditLine *el, wchar_t *cp)
    387 {
    388 	struct macros *ma = &el->el_read->macros;
    389 	int num_read;
    390 
    391 	terminal__flush(el);
    392 	for (;;) {
    393 		if (ma->level < 0)
    394 			break;
    395 
    396 		if (ma->macro[0][ma->offset] == '\0') {
    397 			read_pop(ma);
    398 			continue;
    399 		}
    400 
    401 		*cp = ma->macro[0][ma->offset++];
    402 
    403 		if (ma->macro[0][ma->offset] == '\0') {
    404 			/* Needed for QuoteMode On */
    405 			read_pop(ma);
    406 		}
    407 
    408 		return 1;
    409 	}
    410 
    411 	if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
    412 		return 0;
    413 
    414 	num_read = (*el->el_read->read_char)(el, cp);
    415 
    416 	/*
    417 	 * Remember the original reason of a read failure
    418 	 * such that el_wgets() can restore it after doing
    419 	 * various cleanup operation that might change errno.
    420 	 */
    421 	if (num_read < 0)
    422 		el->el_read->read_errno = errno;
    423 
    424 	return num_read;
    425 }
    426 
    427 libedit_private void
    428 read_prepare(EditLine *el)
    429 {
    430 	if (el->el_flags & HANDLE_SIGNALS)
    431 		sig_set(el);
    432 	if (el->el_flags & NO_TTY)
    433 		return;
    434 	if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
    435 		tty_rawmode(el);
    436 
    437 	/* This is relatively cheap, and things go terribly wrong if
    438 	   we have the wrong size. */
    439 	el_resize(el);
    440 	re_clear_display(el);	/* reset the display stuff */
    441 	ch_reset(el);
    442 	re_refresh(el);		/* print the prompt */
    443 
    444 	if (el->el_flags & UNBUFFERED)
    445 		terminal__flush(el);
    446 }
    447 
    448 libedit_private void
    449 read_finish(EditLine *el)
    450 {
    451 	if ((el->el_flags & UNBUFFERED) == 0)
    452 		(void) tty_cookedmode(el);
    453 	if (el->el_flags & HANDLE_SIGNALS)
    454 		sig_clr(el);
    455 }
    456 
    457 static const wchar_t *
    458 noedit_wgets(EditLine *el, int *nread)
    459 {
    460 	el_line_t	*lp = &el->el_line;
    461 	int		 num;
    462 
    463 	while ((num = (*el->el_read->read_char)(el, lp->lastchar)) == 1) {
    464 		if (lp->lastchar + 1 >= lp->limit &&
    465 		    !ch_enlargebufs(el, (size_t)2))
    466 			break;
    467 		lp->lastchar++;
    468 		if (el->el_flags & UNBUFFERED ||
    469 		    lp->lastchar[-1] == '\r' ||
    470 		    lp->lastchar[-1] == '\n')
    471 			break;
    472 	}
    473 	if (num == -1 && errno == EINTR)
    474 		lp->lastchar = lp->buffer;
    475 	lp->cursor = lp->lastchar;
    476 	*lp->lastchar = '\0';
    477 	*nread = (int)(lp->lastchar - lp->buffer);
    478 	return *nread ? lp->buffer : NULL;
    479 }
    480 
    481 const wchar_t *
    482 el_wgets(EditLine *el, int *nread)
    483 {
    484 	int retval;
    485 	el_action_t cmdnum = 0;
    486 	int num;		/* how many chars we have read at NL */
    487 	wchar_t ch;
    488 	int nrb;
    489 
    490 	if (nread == NULL)
    491 		nread = &nrb;
    492 	*nread = 0;
    493 	el->el_read->read_errno = 0;
    494 
    495 	if (el->el_flags & NO_TTY) {
    496 		el->el_line.lastchar = el->el_line.buffer;
    497 		return noedit_wgets(el, nread);
    498 	}
    499 
    500 #ifdef FIONREAD
    501 	if (el->el_tty.t_mode == EX_IO && el->el_read->macros.level < 0) {
    502 		int chrs = 0;
    503 
    504 		(void) ioctl(el->el_infd, FIONREAD, &chrs);
    505 		if (chrs == 0) {
    506 			if (tty_rawmode(el) < 0) {
    507 				errno = 0;
    508 				*nread = 0;
    509 				return NULL;
    510 			}
    511 		}
    512 	}
    513 #endif /* FIONREAD */
    514 
    515 	if ((el->el_flags & UNBUFFERED) == 0)
    516 		read_prepare(el);
    517 
    518 	if (el->el_flags & EDIT_DISABLED) {
    519 		if ((el->el_flags & UNBUFFERED) == 0)
    520 			el->el_line.lastchar = el->el_line.buffer;
    521 		terminal__flush(el);
    522 		return noedit_wgets(el, nread);
    523 	}
    524 
    525 	for (num = -1; num == -1;) {  /* while still editing this line */
    526 		/* if EOF or error */
    527 		if (read_getcmd(el, &cmdnum, &ch) == -1)
    528 			break;
    529 		if ((size_t)cmdnum >= el->el_map.nfunc) /* BUG CHECK command */
    530 			continue;	/* try again */
    531 		/* now do the real command */
    532 		/* vi redo needs these way down the levels... */
    533 		el->el_state.thiscmd = cmdnum;
    534 		el->el_state.thisch = ch;
    535 		if (el->el_map.type == MAP_VI &&
    536 		    el->el_map.current == el->el_map.key &&
    537 		    el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
    538 			if (cmdnum == VI_DELETE_PREV_CHAR &&
    539 			    el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
    540 			    && iswprint(el->el_chared.c_redo.pos[-1]))
    541 				el->el_chared.c_redo.pos--;
    542 			else
    543 				*el->el_chared.c_redo.pos++ = ch;
    544 		}
    545 		retval = (*el->el_map.func[cmdnum]) (el, ch);
    546 
    547 		/* save the last command here */
    548 		el->el_state.lastcmd = cmdnum;
    549 
    550 		/* use any return value */
    551 		switch (retval) {
    552 		case CC_CURSOR:
    553 			re_refresh_cursor(el);
    554 			break;
    555 
    556 		case CC_REDISPLAY:
    557 			re_clear_lines(el);
    558 			re_clear_display(el);
    559 			/* FALLTHROUGH */
    560 
    561 		case CC_REFRESH:
    562 			re_refresh(el);
    563 			break;
    564 
    565 		case CC_REFRESH_BEEP:
    566 			re_refresh(el);
    567 			terminal_beep(el);
    568 			break;
    569 
    570 		case CC_NORM:	/* normal char */
    571 			break;
    572 
    573 		case CC_ARGHACK:	/* Suggested by Rich Salz */
    574 			/* <rsalz (at) pineapple.bbn.com> */
    575 			continue;	/* keep going... */
    576 
    577 		case CC_EOF:	/* end of file typed */
    578 			if ((el->el_flags & UNBUFFERED) == 0)
    579 				num = 0;
    580 			else if (num == -1) {
    581 				*el->el_line.lastchar++ = CONTROL('d');
    582 				el->el_line.cursor = el->el_line.lastchar;
    583 				num = 1;
    584 			}
    585 			break;
    586 
    587 		case CC_NEWLINE:	/* normal end of line */
    588 			num = (int)(el->el_line.lastchar - el->el_line.buffer);
    589 			break;
    590 
    591 		case CC_FATAL:	/* fatal error, reset to known state */
    592 			/* put (real) cursor in a known place */
    593 			re_clear_display(el);	/* reset the display stuff */
    594 			ch_reset(el);	/* reset the input pointers */
    595 			read_clearmacros(&el->el_read->macros);
    596 			re_refresh(el); /* print the prompt again */
    597 			break;
    598 
    599 		case CC_ERROR:
    600 		default:	/* functions we don't know about */
    601 			terminal_beep(el);
    602 			terminal__flush(el);
    603 			break;
    604 		}
    605 		el->el_state.argument = 1;
    606 		el->el_state.doingarg = 0;
    607 		el->el_chared.c_vcmd.action = NOP;
    608 		if (el->el_flags & UNBUFFERED)
    609 			break;
    610 	}
    611 
    612 	terminal__flush(el);		/* flush any buffered output */
    613 	/* make sure the tty is set up correctly */
    614 	if ((el->el_flags & UNBUFFERED) == 0) {
    615 		read_finish(el);
    616 		*nread = num != -1 ? num : 0;
    617 	} else
    618 		*nread = (int)(el->el_line.lastchar - el->el_line.buffer);
    619 
    620 	if (*nread == 0) {
    621 		if (num == -1) {
    622 			*nread = -1;
    623 			if (el->el_read->read_errno)
    624 				errno = el->el_read->read_errno;
    625 		}
    626 		return NULL;
    627 	} else
    628 		return el->el_line.buffer;
    629 }
    630