Home | History | Annotate | Line # | Download | only in gen
vis.c revision 1.77
      1 /*	$NetBSD: vis.c,v 1.77 2023/08/12 12:46:33 riastradh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 /*-
     33  * Copyright (c) 1999, 2005 The NetBSD Foundation, Inc.
     34  * All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  *
     45  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     46  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     47  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     48  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     49  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     50  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     51  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     52  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     53  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     54  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     55  * POSSIBILITY OF SUCH DAMAGE.
     56  */
     57 
     58 #include <sys/cdefs.h>
     59 #if defined(LIBC_SCCS) && !defined(lint)
     60 __RCSID("$NetBSD: vis.c,v 1.77 2023/08/12 12:46:33 riastradh Exp $");
     61 #endif /* LIBC_SCCS and not lint */
     62 #ifdef __FBSDID
     63 __FBSDID("$FreeBSD$");
     64 #define	_DIAGASSERT(x)	assert(x)
     65 #endif
     66 
     67 #include "namespace.h"
     68 #include <sys/types.h>
     69 #include <sys/param.h>
     70 
     71 #include <assert.h>
     72 #include <vis.h>
     73 #include <errno.h>
     74 #include <stdlib.h>
     75 #include <wchar.h>
     76 #include <wctype.h>
     77 
     78 #ifdef __weak_alias
     79 __weak_alias(strvisx,_strvisx)
     80 #endif
     81 
     82 #if !HAVE_VIS || !HAVE_SVIS
     83 #include <ctype.h>
     84 #include <limits.h>
     85 #include <stdio.h>
     86 #include <string.h>
     87 
     88 /*
     89  * The reason for going through the trouble to deal with character encodings
     90  * in vis(3), is that we use this to safe encode output of commands. This
     91  * safe encoding varies depending on the character set. For example if we
     92  * display ps output in French, we don't want to display French characters
     93  * as M-foo.
     94  */
     95 
     96 static wchar_t *do_svis(wchar_t *, wint_t, int, wint_t, const wchar_t *);
     97 
     98 #undef BELL
     99 #define BELL L'\a'
    100 
    101 #if defined(LC_C_LOCALE)
    102 #define iscgraph(c)      isgraph_l(c, LC_C_LOCALE)
    103 #else
    104 /* Keep it simple for now, no locale stuff */
    105 #define iscgraph(c)	isgraph(c)
    106 #ifdef notyet
    107 #include <locale.h>
    108 static int
    109 iscgraph(int c) {
    110 	int rv;
    111 	char *ol;
    112 
    113 	ol = setlocale(LC_CTYPE, "C");
    114 	rv = isgraph(c);
    115 	if (ol)
    116 		setlocale(LC_CTYPE, ol);
    117 	return rv;
    118 }
    119 #endif
    120 #endif
    121 
    122 #define ISGRAPH(flags, c) \
    123     (((flags) & VIS_NOLOCALE) ? iscgraph(c) : iswgraph(c))
    124 
    125 #define iswoctal(c)	(((u_char)(c)) >= L'0' && ((u_char)(c)) <= L'7')
    126 #define iswwhite(c)	(c == L' ' || c == L'\t' || c == L'\n')
    127 #define iswsafe(c)	(c == L'\b' || c == BELL || c == L'\r')
    128 #define xtoa(c)		L"0123456789abcdef"[c]
    129 #define XTOA(c)		L"0123456789ABCDEF"[c]
    130 
    131 #define MAXEXTRAS	30
    132 
    133 static const wchar_t char_shell[] = L"'`\";&<>()|{}]\\$!^~";
    134 static const wchar_t char_glob[] = L"*?[#";
    135 
    136 #if !HAVE_NBTOOL_CONFIG_H
    137 #ifndef __NetBSD__
    138 /*
    139  * On NetBSD MB_LEN_MAX is currently 32 which does not fit on any integer
    140  * integral type and it is probably wrong, since currently the maximum
    141  * number of bytes and character needs is 6. Until this is fixed, the
    142  * loops below are using sizeof(uint64_t) - 1 instead of MB_LEN_MAX, and
    143  * the assertion is commented out.
    144  */
    145 #ifdef __FreeBSD__
    146 /*
    147  * On FreeBSD including <sys/systm.h> for CTASSERT only works in kernel
    148  * mode.
    149  */
    150 #ifndef CTASSERT
    151 #define CTASSERT(x)             _CTASSERT(x, __LINE__)
    152 #define _CTASSERT(x, y)         __CTASSERT(x, y)
    153 #define __CTASSERT(x, y)        typedef char __assert ## y[(x) ? 1 : -1]
    154 #endif
    155 #endif /* __FreeBSD__ */
    156 CTASSERT(MB_LEN_MAX <= sizeof(uint64_t));
    157 #endif /* !__NetBSD__ */
    158 #endif
    159 
    160 /*
    161  * This is do_hvis, for HTTP style (RFC 1808)
    162  */
    163 static wchar_t *
    164 do_hvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
    165 {
    166 	if (iswalnum(c)
    167 	    /* safe */
    168 	    || c == L'$' || c == L'-' || c == L'_' || c == L'.' || c == L'+'
    169 	    /* extra */
    170 	    || c == L'!' || c == L'*' || c == L'\'' || c == L'(' || c == L')'
    171 	    || c == L',')
    172 		dst = do_svis(dst, c, flags, nextc, extra);
    173 	else {
    174 		*dst++ = L'%';
    175 		*dst++ = xtoa(((unsigned int)c >> 4) & 0xf);
    176 		*dst++ = xtoa((unsigned int)c & 0xf);
    177 	}
    178 
    179 	return dst;
    180 }
    181 
    182 /*
    183  * This is do_mvis, for Quoted-Printable MIME (RFC 2045)
    184  * NB: No handling of long lines or CRLF.
    185  */
    186 static wchar_t *
    187 do_mvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
    188 {
    189 	if ((c != L'\n') &&
    190 	    /* Space at the end of the line */
    191 	    ((iswspace(c) && (nextc == L'\r' || nextc == L'\n')) ||
    192 	    /* Out of range */
    193 	    (!iswspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) ||
    194 	    /* Specific char to be escaped */
    195 	    wcschr(L"#$@[\\]^`{|}~", c) != NULL)) {
    196 		*dst++ = L'=';
    197 		*dst++ = XTOA(((unsigned int)c >> 4) & 0xf);
    198 		*dst++ = XTOA((unsigned int)c & 0xf);
    199 	} else
    200 		dst = do_svis(dst, c, flags, nextc, extra);
    201 	return dst;
    202 }
    203 
    204 /*
    205  * Output single byte of multibyte character.
    206  */
    207 static wchar_t *
    208 do_mbyte(wchar_t *dst, wint_t c, int flags, wint_t nextc, int iswextra)
    209 {
    210 	if (flags & VIS_CSTYLE) {
    211 		switch (c) {
    212 		case L'\n':
    213 			*dst++ = L'\\'; *dst++ = L'n';
    214 			return dst;
    215 		case L'\r':
    216 			*dst++ = L'\\'; *dst++ = L'r';
    217 			return dst;
    218 		case L'\b':
    219 			*dst++ = L'\\'; *dst++ = L'b';
    220 			return dst;
    221 		case BELL:
    222 			*dst++ = L'\\'; *dst++ = L'a';
    223 			return dst;
    224 		case L'\v':
    225 			*dst++ = L'\\'; *dst++ = L'v';
    226 			return dst;
    227 		case L'\t':
    228 			*dst++ = L'\\'; *dst++ = L't';
    229 			return dst;
    230 		case L'\f':
    231 			*dst++ = L'\\'; *dst++ = L'f';
    232 			return dst;
    233 		case L' ':
    234 			*dst++ = L'\\'; *dst++ = L's';
    235 			return dst;
    236 		case L'\0':
    237 			*dst++ = L'\\'; *dst++ = L'0';
    238 			if (iswoctal(nextc)) {
    239 				*dst++ = L'0';
    240 				*dst++ = L'0';
    241 			}
    242 			return dst;
    243 		/* We cannot encode these characters in VIS_CSTYLE
    244 		 * because they special meaning */
    245 		case L'n':
    246 		case L'r':
    247 		case L'b':
    248 		case L'a':
    249 		case L'v':
    250 		case L't':
    251 		case L'f':
    252 		case L's':
    253 		case L'0':
    254 		case L'M':
    255 		case L'^':
    256 		case L'$': /* vis(1) -l */
    257 			break;
    258 		default:
    259 			if (ISGRAPH(flags, c) && !iswoctal(c)) {
    260 				*dst++ = L'\\';
    261 				*dst++ = c;
    262 				return dst;
    263 			}
    264 		}
    265 	}
    266 	if (iswextra || ((c & 0177) == L' ') || (flags & VIS_OCTAL)) {
    267 		*dst++ = L'\\';
    268 		*dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + L'0';
    269 		*dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + L'0';
    270 		*dst++ =			     (c	      & 07) + L'0';
    271 	} else {
    272 		if ((flags & VIS_NOSLASH) == 0)
    273 			*dst++ = L'\\';
    274 
    275 		if (c & 0200) {
    276 			c &= 0177;
    277 			*dst++ = L'M';
    278 		}
    279 
    280 		if (iswcntrl(c)) {
    281 			*dst++ = L'^';
    282 			if (c == 0177)
    283 				*dst++ = L'?';
    284 			else
    285 				*dst++ = c + L'@';
    286 		} else {
    287 			*dst++ = L'-';
    288 			*dst++ = c;
    289 		}
    290 	}
    291 
    292 	return dst;
    293 }
    294 
    295 /*
    296  * This is do_vis, the central code of vis.
    297  * dst:	      Pointer to the destination buffer
    298  * c:	      Character to encode
    299  * flags:     Flags word
    300  * nextc:     The character following 'c'
    301  * extra:     Pointer to the list of extra characters to be
    302  *	      backslash-protected.
    303  */
    304 static wchar_t *
    305 do_svis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
    306 {
    307 	int iswextra, i, shft;
    308 	uint64_t bmsk, wmsk;
    309 
    310 	iswextra = wcschr(extra, c) != NULL;
    311 	if (!iswextra && (ISGRAPH(flags, c) || iswwhite(c) ||
    312 	    ((flags & VIS_SAFE) && iswsafe(c)))) {
    313 		*dst++ = c;
    314 		return dst;
    315 	}
    316 
    317 	/* See comment in istrsenvisx() output loop, below. */
    318 	wmsk = 0;
    319 	for (i = sizeof(wmsk) - 1; i >= 0; i--) {
    320 		shft = i * NBBY;
    321 		bmsk = (uint64_t)0xffLL << shft;
    322 		wmsk |= bmsk;
    323 		if ((c & wmsk) || i == 0)
    324 			dst = do_mbyte(dst, (wint_t)(
    325 			    (uint64_t)(c & bmsk) >> shft),
    326 			    flags, nextc, iswextra);
    327 	}
    328 
    329 	return dst;
    330 }
    331 
    332 typedef wchar_t *(*visfun_t)(wchar_t *, wint_t, int, wint_t, const wchar_t *);
    333 
    334 /*
    335  * Return the appropriate encoding function depending on the flags given.
    336  */
    337 static visfun_t
    338 getvisfun(int flags)
    339 {
    340 	if (flags & VIS_HTTPSTYLE)
    341 		return do_hvis;
    342 	if (flags & VIS_MIMESTYLE)
    343 		return do_mvis;
    344 	return do_svis;
    345 }
    346 
    347 /*
    348  * Expand list of extra characters to not visually encode.
    349  */
    350 static wchar_t *
    351 makeextralist(int flags, const char *src)
    352 {
    353 	wchar_t *dst, *d;
    354 	size_t len;
    355 	const wchar_t *s;
    356 	mbstate_t mbstate;
    357 
    358 	len = strlen(src);
    359 	if ((dst = calloc(len + MAXEXTRAS, sizeof(*dst))) == NULL)
    360 		return NULL;
    361 
    362 	memset(&mbstate, 0, sizeof(mbstate));
    363 	if ((flags & VIS_NOLOCALE)
    364 	    || mbsrtowcs(dst, &src, len, &mbstate) == (size_t)-1) {
    365 		size_t i;
    366 		for (i = 0; i < len; i++)
    367 			dst[i] = (wchar_t)(u_char)src[i];
    368 		d = dst + len;
    369 	} else
    370 		d = dst + wcslen(dst);
    371 
    372 	if (flags & VIS_GLOB)
    373 		for (s = char_glob; *s; *d++ = *s++)
    374 			continue;
    375 
    376 	if (flags & VIS_SHELL)
    377 		for (s = char_shell; *s; *d++ = *s++)
    378 			continue;
    379 
    380 	if (flags & VIS_SP) *d++ = L' ';
    381 	if (flags & VIS_TAB) *d++ = L'\t';
    382 	if (flags & VIS_NL) *d++ = L'\n';
    383 	if (flags & VIS_DQ) *d++ = L'"';
    384 	if ((flags & VIS_NOSLASH) == 0) *d++ = L'\\';
    385 	*d = L'\0';
    386 
    387 	return dst;
    388 }
    389 
    390 /*
    391  * istrsenvisx()
    392  * 	The main internal function.
    393  *	All user-visible functions call this one.
    394  */
    395 static int
    396 istrsenvisx(char **mbdstp, size_t *dlen, const char *mbsrc, size_t mblength,
    397     int flags, const char *mbextra, int *cerr_ptr)
    398 {
    399 	wchar_t *dst, *src, *pdst, *psrc, *start, *extra;
    400 	size_t len, olen;
    401 	uint64_t bmsk, wmsk;
    402 	wint_t c;
    403 	visfun_t f;
    404 	int clen = 0, cerr, error = -1, i, shft;
    405 	char *mbdst, *mdst;
    406 	ssize_t mbslength;
    407 	size_t maxolen;
    408 	mbstate_t mbstate;
    409 
    410 	_DIAGASSERT(mbdstp != NULL);
    411 	_DIAGASSERT(mbsrc != NULL || mblength == 0);
    412 	_DIAGASSERT(mbextra != NULL);
    413 
    414 	mbslength = (ssize_t)mblength;
    415 	/*
    416 	 * When inputing a single character, must also read in the
    417 	 * next character for nextc, the look-ahead character.
    418 	 */
    419 	if (mbslength == 1)
    420 		mbslength++;
    421 
    422 	/*
    423 	 * Input (mbsrc) is a char string considered to be multibyte
    424 	 * characters.  The input loop will read this string pulling
    425 	 * one character, possibly multiple bytes, from mbsrc and
    426 	 * converting each to wchar_t in src.
    427 	 *
    428 	 * The vis conversion will be done using the wide char
    429 	 * wchar_t string.
    430 	 *
    431 	 * This will then be converted back to a multibyte string to
    432 	 * return to the caller.
    433 	 */
    434 
    435 	/* Allocate space for the wide char strings */
    436 	psrc = pdst = extra = NULL;
    437 	mdst = NULL;
    438 	if ((psrc = calloc(mbslength + 1, sizeof(*psrc))) == NULL)
    439 		return -1;
    440 	if ((pdst = calloc((16 * mbslength) + 1, sizeof(*pdst))) == NULL)
    441 		goto out;
    442 	if (*mbdstp == NULL) {
    443 		if ((mdst = calloc((16 * mbslength) + 1, sizeof(*mdst))) == NULL)
    444 			goto out;
    445 		*mbdstp = mdst;
    446 	}
    447 
    448 	mbdst = *mbdstp;
    449 	dst = pdst;
    450 	src = psrc;
    451 
    452 	if (flags & VIS_NOLOCALE) {
    453 		/* Do one byte at a time conversion */
    454 		cerr = 1;
    455 	} else {
    456 		/* Use caller's multibyte conversion error flag. */
    457 		cerr = cerr_ptr ? *cerr_ptr : 0;
    458 	}
    459 
    460 	/*
    461 	 * Input loop.
    462 	 * Handle up to mblength characters (not bytes).  We do not
    463 	 * stop at NULs because we may be processing a block of data
    464 	 * that includes NULs.
    465 	 */
    466 	memset(&mbstate, 0, sizeof(mbstate));
    467 	while (mbslength > 0) {
    468 		/* Convert one multibyte character to wchar_t. */
    469 		if (!cerr)
    470 			clen = mbrtowc(src, mbsrc,
    471 			    (mbslength < MB_LEN_MAX
    472 				? mbslength
    473 				: MB_LEN_MAX),
    474 			    &mbstate);
    475 		if (cerr || clen < 0) {
    476 			/* Conversion error, process as a byte instead. */
    477 			*src = (wint_t)(u_char)*mbsrc;
    478 			clen = 1;
    479 			cerr = 1;
    480 		}
    481 		if (clen == 0) {
    482 			/*
    483 			 * NUL in input gives 0 return value. process
    484 			 * as single NUL byte and keep going.
    485 			 */
    486 			clen = 1;
    487 		}
    488 		/* Advance buffer character pointer. */
    489 		src++;
    490 		/* Advance input pointer by number of bytes read. */
    491 		mbsrc += clen;
    492 		/* Decrement input byte count. */
    493 		mbslength -= clen;
    494 	}
    495 	len = src - psrc;
    496 	src = psrc;
    497 
    498 	/*
    499 	 * In the single character input case, we will have actually
    500 	 * processed two characters, c and nextc.  Reset len back to
    501 	 * just a single character.
    502 	 */
    503 	if (mblength < len)
    504 		len = mblength;
    505 
    506 	/* Convert extra argument to list of characters for this mode. */
    507 	extra = makeextralist(flags, mbextra);
    508 	if (!extra) {
    509 		if (dlen && *dlen == 0) {
    510 			errno = ENOSPC;
    511 			goto out;
    512 		}
    513 		*mbdst = '\0';	/* can't create extra, return "" */
    514 		error = 0;
    515 		goto out;
    516 	}
    517 
    518 	/* Look up which processing function to call. */
    519 	f = getvisfun(flags);
    520 
    521 	/*
    522 	 * Main processing loop.
    523 	 * Call do_Xvis processing function one character at a time
    524 	 * with next character available for look-ahead.
    525 	 */
    526 	for (start = dst; len > 0; len--) {
    527 		c = *src++;
    528 		dst = (*f)(dst, c, flags, len >= 1 ? *src : L'\0', extra);
    529 		if (dst == NULL) {
    530 			errno = ENOSPC;
    531 			goto out;
    532 		}
    533 	}
    534 
    535 	/* Terminate the string in the buffer. */
    536 	*dst = L'\0';
    537 
    538 	/*
    539 	 * Output loop.
    540 	 * Convert wchar_t string back to multibyte output string.
    541 	 * If we have hit a multi-byte conversion error on input,
    542 	 * output byte-by-byte here.  Else use wctomb().
    543 	 */
    544 	len = wcslen(start);
    545 	maxolen = dlen ? *dlen : (wcslen(start) * MB_LEN_MAX + 1);
    546 	olen = 0;
    547 	memset(&mbstate, 0, sizeof(mbstate));
    548 	for (dst = start; len > 0; len--) {
    549 		if (!cerr)
    550 			clen = wcrtomb(mbdst, *dst, &mbstate);
    551 		if (cerr || clen < 0) {
    552 			/*
    553 			 * Conversion error, process as a byte(s) instead.
    554 			 * Examine each byte and higher-order bytes for
    555 			 * data.  E.g.,
    556 			 *	0x000000000000a264 -> a2 64
    557 			 *	0x000000001f00a264 -> 1f 00 a2 64
    558 			 */
    559 			clen = 0;
    560 			wmsk = 0;
    561 			for (i = sizeof(wmsk) - 1; i >= 0; i--) {
    562 				shft = i * NBBY;
    563 				bmsk = (uint64_t)0xffLL << shft;
    564 				wmsk |= bmsk;
    565 				if ((*dst & wmsk) || i == 0)
    566 					mbdst[clen++] = (char)(
    567 					    (uint64_t)(*dst & bmsk) >>
    568 					    shft);
    569 			}
    570 			cerr = 1;
    571 		}
    572 		/* If this character would exceed our output limit, stop. */
    573 		if (olen + clen > maxolen)
    574 			break;
    575 		/* Advance output pointer by number of bytes written. */
    576 		mbdst += clen;
    577 		/* Advance buffer character pointer. */
    578 		dst++;
    579 		/* Incrment output character count. */
    580 		olen += clen;
    581 	}
    582 
    583 	/* Terminate the output string. */
    584 	*mbdst = '\0';
    585 
    586 	if (flags & VIS_NOLOCALE) {
    587 		/* Pass conversion error flag out. */
    588 		if (cerr_ptr)
    589 			*cerr_ptr = cerr;
    590 	}
    591 
    592 	free(extra);
    593 	free(pdst);
    594 	free(psrc);
    595 
    596 	return (int)olen;
    597 out:
    598 	free(extra);
    599 	free(pdst);
    600 	free(psrc);
    601 	free(mdst);
    602 	return error;
    603 }
    604 
    605 static int
    606 istrsenvisxl(char **mbdstp, size_t *dlen, const char *mbsrc,
    607     int flags, const char *mbextra, int *cerr_ptr)
    608 {
    609 	return istrsenvisx(mbdstp, dlen, mbsrc,
    610 	    mbsrc != NULL ? strlen(mbsrc) : 0, flags, mbextra, cerr_ptr);
    611 }
    612 
    613 #endif
    614 
    615 #if !HAVE_SVIS
    616 /*
    617  *	The "svis" variants all take an "extra" arg that is a pointer
    618  *	to a NUL-terminated list of characters to be encoded, too.
    619  *	These functions are useful e. g. to encode strings in such a
    620  *	way so that they are not interpreted by a shell.
    621  */
    622 
    623 char *
    624 svis(char *mbdst, int c, int flags, int nextc, const char *mbextra)
    625 {
    626 	char cc[2];
    627 	int ret;
    628 
    629 	cc[0] = c;
    630 	cc[1] = nextc;
    631 
    632 	ret = istrsenvisx(&mbdst, NULL, cc, 1, flags, mbextra, NULL);
    633 	if (ret < 0)
    634 		return NULL;
    635 	return mbdst + ret;
    636 }
    637 
    638 char *
    639 snvis(char *mbdst, size_t dlen, int c, int flags, int nextc, const char *mbextra)
    640 {
    641 	char cc[2];
    642 	int ret;
    643 
    644 	cc[0] = c;
    645 	cc[1] = nextc;
    646 
    647 	ret = istrsenvisx(&mbdst, &dlen, cc, 1, flags, mbextra, NULL);
    648 	if (ret < 0)
    649 		return NULL;
    650 	return mbdst + ret;
    651 }
    652 
    653 int
    654 strsvis(char *mbdst, const char *mbsrc, int flags, const char *mbextra)
    655 {
    656 	return istrsenvisxl(&mbdst, NULL, mbsrc, flags, mbextra, NULL);
    657 }
    658 
    659 int
    660 strsnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags, const char *mbextra)
    661 {
    662 	return istrsenvisxl(&mbdst, &dlen, mbsrc, flags, mbextra, NULL);
    663 }
    664 
    665 int
    666 strsvisx(char *mbdst, const char *mbsrc, size_t len, int flags, const char *mbextra)
    667 {
    668 	return istrsenvisx(&mbdst, NULL, mbsrc, len, flags, mbextra, NULL);
    669 }
    670 
    671 int
    672 strsnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
    673     const char *mbextra)
    674 {
    675 	return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, mbextra, NULL);
    676 }
    677 
    678 int
    679 strsenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
    680     const char *mbextra, int *cerr_ptr)
    681 {
    682 	return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, mbextra, cerr_ptr);
    683 }
    684 #endif
    685 
    686 #if !HAVE_VIS
    687 /*
    688  * vis - visually encode characters
    689  */
    690 char *
    691 vis(char *mbdst, int c, int flags, int nextc)
    692 {
    693 	char cc[2];
    694 	int ret;
    695 
    696 	cc[0] = c;
    697 	cc[1] = nextc;
    698 
    699 	ret = istrsenvisx(&mbdst, NULL, cc, 1, flags, "", NULL);
    700 	if (ret < 0)
    701 		return NULL;
    702 	return mbdst + ret;
    703 }
    704 
    705 char *
    706 nvis(char *mbdst, size_t dlen, int c, int flags, int nextc)
    707 {
    708 	char cc[2];
    709 	int ret;
    710 
    711 	cc[0] = c;
    712 	cc[1] = nextc;
    713 
    714 	ret = istrsenvisx(&mbdst, &dlen, cc, 1, flags, "", NULL);
    715 	if (ret < 0)
    716 		return NULL;
    717 	return mbdst + ret;
    718 }
    719 
    720 /*
    721  * strvis - visually encode characters from src into dst
    722  *
    723  *	Dst must be 4 times the size of src to account for possible
    724  *	expansion.  The length of dst, not including the trailing NULL,
    725  *	is returned.
    726  */
    727 
    728 int
    729 strvis(char *mbdst, const char *mbsrc, int flags)
    730 {
    731 	return istrsenvisxl(&mbdst, NULL, mbsrc, flags, "", NULL);
    732 }
    733 
    734 int
    735 strnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags)
    736 {
    737 	return istrsenvisxl(&mbdst, &dlen, mbsrc, flags, "", NULL);
    738 }
    739 
    740 int
    741 stravis(char **mbdstp, const char *mbsrc, int flags)
    742 {
    743 	*mbdstp = NULL;
    744 	return istrsenvisxl(mbdstp, NULL, mbsrc, flags, "", NULL);
    745 }
    746 
    747 /*
    748  * strvisx - visually encode characters from src into dst
    749  *
    750  *	Dst must be 4 times the size of src to account for possible
    751  *	expansion.  The length of dst, not including the trailing NULL,
    752  *	is returned.
    753  *
    754  *	Strvisx encodes exactly len characters from src into dst.
    755  *	This is useful for encoding a block of data.
    756  */
    757 
    758 int
    759 strvisx(char *mbdst, const char *mbsrc, size_t len, int flags)
    760 {
    761 	return istrsenvisx(&mbdst, NULL, mbsrc, len, flags, "", NULL);
    762 }
    763 
    764 int
    765 strnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags)
    766 {
    767 	return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, "", NULL);
    768 }
    769 
    770 int
    771 strenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
    772     int *cerr_ptr)
    773 {
    774 	return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, "", cerr_ptr);
    775 }
    776 #endif
    777