xref: /freebsd/contrib/libc-vis/vis.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*	$NetBSD: vis.c,v 1.62 2014/09/08 17:35:01 christos 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 1.62 2014/09/08 17:35:01 christos 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 #define iswoctal(c)	(((u_char)(c)) >= L'0' && ((u_char)(c)) <= L'7')
102 #define iswwhite(c)	(c == L' ' || c == L'\t' || c == L'\n')
103 #define iswsafe(c)	(c == L'\b' || c == BELL || c == L'\r')
104 #define xtoa(c)		L"0123456789abcdef"[c]
105 #define XTOA(c)		L"0123456789ABCDEF"[c]
106 
107 #define MAXEXTRAS	10
108 
109 #if !HAVE_NBTOOL_CONFIG_H
110 #ifndef __NetBSD__
111 /*
112  * On NetBSD MB_LEN_MAX is currently 32 which does not fit on any integer
113  * integral type and it is probably wrong, since currently the maximum
114  * number of bytes and character needs is 6. Until this is fixed, the
115  * loops below are using sizeof(uint64_t) - 1 instead of MB_LEN_MAX, and
116  * the assertion is commented out.
117  */
118 #ifdef __FreeBSD__
119 /*
120  * On FreeBSD including <sys/systm.h> for CTASSERT only works in kernel
121  * mode.
122  */
123 #ifndef CTASSERT
124 #define CTASSERT(x)             _CTASSERT(x, __LINE__)
125 #define _CTASSERT(x, y)         __CTASSERT(x, y)
126 #define __CTASSERT(x, y)        typedef char __assert ## y[(x) ? 1 : -1]
127 #endif
128 #endif /* __FreeBSD__ */
129 CTASSERT(MB_LEN_MAX <= sizeof(uint64_t));
130 #endif /* !__NetBSD__ */
131 #endif
132 
133 /*
134  * This is do_hvis, for HTTP style (RFC 1808)
135  */
136 static wchar_t *
137 do_hvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
138 {
139 	if (iswalnum(c)
140 	    /* safe */
141 	    || c == L'$' || c == L'-' || c == L'_' || c == L'.' || c == L'+'
142 	    /* extra */
143 	    || c == L'!' || c == L'*' || c == L'\'' || c == L'(' || c == L')'
144 	    || c == L',')
145 		dst = do_svis(dst, c, flags, nextc, extra);
146 	else {
147 		*dst++ = L'%';
148 		*dst++ = xtoa(((unsigned int)c >> 4) & 0xf);
149 		*dst++ = xtoa((unsigned int)c & 0xf);
150 	}
151 
152 	return dst;
153 }
154 
155 /*
156  * This is do_mvis, for Quoted-Printable MIME (RFC 2045)
157  * NB: No handling of long lines or CRLF.
158  */
159 static wchar_t *
160 do_mvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
161 {
162 	if ((c != L'\n') &&
163 	    /* Space at the end of the line */
164 	    ((iswspace(c) && (nextc == L'\r' || nextc == L'\n')) ||
165 	    /* Out of range */
166 	    (!iswspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) ||
167 	    /* Specific char to be escaped */
168 	    wcschr(L"#$@[\\]^`{|}~", c) != NULL)) {
169 		*dst++ = L'=';
170 		*dst++ = XTOA(((unsigned int)c >> 4) & 0xf);
171 		*dst++ = XTOA((unsigned int)c & 0xf);
172 	} else
173 		dst = do_svis(dst, c, flags, nextc, extra);
174 	return dst;
175 }
176 
177 /*
178  * Output single byte of multibyte character.
179  */
180 static wchar_t *
181 do_mbyte(wchar_t *dst, wint_t c, int flags, wint_t nextc, int iswextra)
182 {
183 	if (flags & VIS_CSTYLE) {
184 		switch (c) {
185 		case L'\n':
186 			*dst++ = L'\\'; *dst++ = L'n';
187 			return dst;
188 		case L'\r':
189 			*dst++ = L'\\'; *dst++ = L'r';
190 			return dst;
191 		case L'\b':
192 			*dst++ = L'\\'; *dst++ = L'b';
193 			return dst;
194 		case BELL:
195 			*dst++ = L'\\'; *dst++ = L'a';
196 			return dst;
197 		case L'\v':
198 			*dst++ = L'\\'; *dst++ = L'v';
199 			return dst;
200 		case L'\t':
201 			*dst++ = L'\\'; *dst++ = L't';
202 			return dst;
203 		case L'\f':
204 			*dst++ = L'\\'; *dst++ = L'f';
205 			return dst;
206 		case L' ':
207 			*dst++ = L'\\'; *dst++ = L's';
208 			return dst;
209 		case L'\0':
210 			*dst++ = L'\\'; *dst++ = L'0';
211 			if (iswoctal(nextc)) {
212 				*dst++ = L'0';
213 				*dst++ = L'0';
214 			}
215 			return dst;
216 		default:
217 			if (iswgraph(c)) {
218 				*dst++ = L'\\';
219 				*dst++ = c;
220 				return dst;
221 			}
222 		}
223 	}
224 	if (iswextra || ((c & 0177) == L' ') || (flags & VIS_OCTAL)) {
225 		*dst++ = L'\\';
226 		*dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + L'0';
227 		*dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + L'0';
228 		*dst++ =			     (c	      & 07) + L'0';
229 	} else {
230 		if ((flags & VIS_NOSLASH) == 0)
231 			*dst++ = L'\\';
232 
233 		if (c & 0200) {
234 			c &= 0177;
235 			*dst++ = L'M';
236 		}
237 
238 		if (iswcntrl(c)) {
239 			*dst++ = L'^';
240 			if (c == 0177)
241 				*dst++ = L'?';
242 			else
243 				*dst++ = c + L'@';
244 		} else {
245 			*dst++ = L'-';
246 			*dst++ = c;
247 		}
248 	}
249 
250 	return dst;
251 }
252 
253 /*
254  * This is do_vis, the central code of vis.
255  * dst:	      Pointer to the destination buffer
256  * c:	      Character to encode
257  * flags:     Flags word
258  * nextc:     The character following 'c'
259  * extra:     Pointer to the list of extra characters to be
260  *	      backslash-protected.
261  */
262 static wchar_t *
263 do_svis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
264 {
265 	int iswextra, i, shft;
266 	uint64_t bmsk, wmsk;
267 
268 	iswextra = wcschr(extra, c) != NULL;
269 	if (!iswextra && (iswgraph(c) || iswwhite(c) ||
270 	    ((flags & VIS_SAFE) && iswsafe(c)))) {
271 		*dst++ = c;
272 		return dst;
273 	}
274 
275 	/* See comment in istrsenvisx() output loop, below. */
276 	wmsk = 0;
277 	for (i = sizeof(wmsk) - 1; i >= 0; i--) {
278 		shft = i * NBBY;
279 		bmsk = (uint64_t)0xffLL << shft;
280 		wmsk |= bmsk;
281 		if ((c & wmsk) || i == 0)
282 			dst = do_mbyte(dst, (wint_t)(
283 			    (uint64_t)(c & bmsk) >> shft),
284 			    flags, nextc, iswextra);
285 	}
286 
287 	return dst;
288 }
289 
290 typedef wchar_t *(*visfun_t)(wchar_t *, wint_t, int, wint_t, const wchar_t *);
291 
292 /*
293  * Return the appropriate encoding function depending on the flags given.
294  */
295 static visfun_t
296 getvisfun(int flags)
297 {
298 	if (flags & VIS_HTTPSTYLE)
299 		return do_hvis;
300 	if (flags & VIS_MIMESTYLE)
301 		return do_mvis;
302 	return do_svis;
303 }
304 
305 /*
306  * Expand list of extra characters to not visually encode.
307  */
308 static wchar_t *
309 makeextralist(int flags, const char *src)
310 {
311 	wchar_t *dst, *d;
312 	size_t len;
313 
314 	len = strlen(src);
315 	if ((dst = calloc(len + MAXEXTRAS, sizeof(*dst))) == NULL)
316 		return NULL;
317 
318 	if (mbstowcs(dst, src, len) == (size_t)-1) {
319 		size_t i;
320 		for (i = 0; i < len; i++)
321 			dst[i] = (wint_t)(u_char)src[i];
322 		d = dst + len;
323 	} else
324 		d = dst + wcslen(dst);
325 
326 	if (flags & VIS_GLOB) {
327 		*d++ = L'*';
328 		*d++ = L'?';
329 		*d++ = L'[';
330 		*d++ = L'#';
331 	}
332 
333 	if (flags & VIS_SP) *d++ = L' ';
334 	if (flags & VIS_TAB) *d++ = L'\t';
335 	if (flags & VIS_NL) *d++ = L'\n';
336 	if ((flags & VIS_NOSLASH) == 0) *d++ = L'\\';
337 	*d = L'\0';
338 
339 	return dst;
340 }
341 
342 /*
343  * istrsenvisx()
344  * 	The main internal function.
345  *	All user-visible functions call this one.
346  */
347 static int
348 istrsenvisx(char *mbdst, size_t *dlen, const char *mbsrc, size_t mblength,
349     int flags, const char *mbextra, int *cerr_ptr)
350 {
351 	wchar_t *dst, *src, *pdst, *psrc, *start, *extra;
352 	size_t len, olen;
353 	uint64_t bmsk, wmsk;
354 	wint_t c;
355 	visfun_t f;
356 	int clen = 0, cerr = 0, error = -1, i, shft;
357 	ssize_t mbslength, maxolen;
358 
359 	_DIAGASSERT(mbdst != NULL);
360 	_DIAGASSERT(mbsrc != NULL || mblength == 0);
361 	_DIAGASSERT(mbextra != NULL);
362 
363 	/*
364 	 * Input (mbsrc) is a char string considered to be multibyte
365 	 * characters.  The input loop will read this string pulling
366 	 * one character, possibly multiple bytes, from mbsrc and
367 	 * converting each to wchar_t in src.
368 	 *
369 	 * The vis conversion will be done using the wide char
370 	 * wchar_t string.
371 	 *
372 	 * This will then be converted back to a multibyte string to
373 	 * return to the caller.
374 	 */
375 
376 	/* Allocate space for the wide char strings */
377 	psrc = pdst = extra = NULL;
378 	if ((psrc = calloc(mblength + 1, sizeof(*psrc))) == NULL)
379 		return -1;
380 	if ((pdst = calloc((4 * mblength) + 1, sizeof(*pdst))) == NULL)
381 		goto out;
382 	dst = pdst;
383 	src = psrc;
384 
385 	/* Use caller's multibyte conversion error flag. */
386 	if (cerr_ptr)
387 		cerr = *cerr_ptr;
388 
389 	/*
390 	 * Input loop.
391 	 * Handle up to mblength characters (not bytes).  We do not
392 	 * stop at NULs because we may be processing a block of data
393 	 * that includes NULs.
394 	 */
395 	mbslength = (ssize_t)mblength;
396 	/*
397 	 * When inputing a single character, must also read in the
398 	 * next character for nextc, the look-ahead character.
399 	 */
400 	if (mbslength == 1)
401 		mbslength++;
402 	while (mbslength > 0) {
403 		/* Convert one multibyte character to wchar_t. */
404 		if (!cerr)
405 			clen = mbtowc(src, mbsrc, MB_LEN_MAX);
406 		if (cerr || clen < 0) {
407 			/* Conversion error, process as a byte instead. */
408 			*src = (wint_t)(u_char)*mbsrc;
409 			clen = 1;
410 			cerr = 1;
411 		}
412 		if (clen == 0)
413 			/*
414 			 * NUL in input gives 0 return value. process
415 			 * as single NUL byte and keep going.
416 			 */
417 			clen = 1;
418 		/* Advance buffer character pointer. */
419 		src++;
420 		/* Advance input pointer by number of bytes read. */
421 		mbsrc += clen;
422 		/* Decrement input byte count. */
423 		mbslength -= clen;
424 	}
425 	len = src - psrc;
426 	src = psrc;
427 	/*
428 	 * In the single character input case, we will have actually
429 	 * processed two characters, c and nextc.  Reset len back to
430 	 * just a single character.
431 	 */
432 	if (mblength < len)
433 		len = mblength;
434 
435 	/* Convert extra argument to list of characters for this mode. */
436 	extra = makeextralist(flags, mbextra);
437 	if (!extra) {
438 		if (dlen && *dlen == 0) {
439 			errno = ENOSPC;
440 			goto out;
441 		}
442 		*mbdst = '\0';		/* can't create extra, return "" */
443 		error = 0;
444 		goto out;
445 	}
446 
447 	/* Look up which processing function to call. */
448 	f = getvisfun(flags);
449 
450 	/*
451 	 * Main processing loop.
452 	 * Call do_Xvis processing function one character at a time
453 	 * with next character available for look-ahead.
454 	 */
455 	for (start = dst; len > 0; len--) {
456 		c = *src++;
457 		dst = (*f)(dst, c, flags, len >= 1 ? *src : L'\0', extra);
458 		if (dst == NULL) {
459 			errno = ENOSPC;
460 			goto out;
461 		}
462 	}
463 
464 	/* Terminate the string in the buffer. */
465 	*dst = L'\0';
466 
467 	/*
468 	 * Output loop.
469 	 * Convert wchar_t string back to multibyte output string.
470 	 * If we have hit a multi-byte conversion error on input,
471 	 * output byte-by-byte here.  Else use wctomb().
472 	 */
473 	len = wcslen(start);
474 	maxolen = dlen ? *dlen : (wcslen(start) * MB_LEN_MAX + 1);
475 	olen = 0;
476 	for (dst = start; len > 0; len--) {
477 		if (!cerr)
478 			clen = wctomb(mbdst, *dst);
479 		if (cerr || clen < 0) {
480 			/*
481 			 * Conversion error, process as a byte(s) instead.
482 			 * Examine each byte and higher-order bytes for
483 			 * data.  E.g.,
484 			 *	0x000000000000a264 -> a2 64
485 			 *	0x000000001f00a264 -> 1f 00 a2 64
486 			 */
487 			clen = 0;
488 			wmsk = 0;
489 			for (i = sizeof(wmsk) - 1; i >= 0; i--) {
490 				shft = i * NBBY;
491 				bmsk = (uint64_t)0xffLL << shft;
492 				wmsk |= bmsk;
493 				if ((*dst & wmsk) || i == 0)
494 					mbdst[clen++] = (char)(
495 					    (uint64_t)(*dst & bmsk) >>
496 					    shft);
497 			}
498 			cerr = 1;
499 		}
500 		/* If this character would exceed our output limit, stop. */
501 		if (olen + clen > (size_t)maxolen)
502 			break;
503 		/* Advance output pointer by number of bytes written. */
504 		mbdst += clen;
505 		/* Advance buffer character pointer. */
506 		dst++;
507 		/* Incrment output character count. */
508 		olen += clen;
509 	}
510 
511 	/* Terminate the output string. */
512 	*mbdst = '\0';
513 
514 	/* Pass conversion error flag out. */
515 	if (cerr_ptr)
516 		*cerr_ptr = cerr;
517 
518 	free(extra);
519 	free(pdst);
520 	free(psrc);
521 
522 	return (int)olen;
523 out:
524 	free(extra);
525 	free(pdst);
526 	free(psrc);
527 	return error;
528 }
529 
530 static int
531 istrsenvisxl(char *mbdst, size_t *dlen, const char *mbsrc,
532     int flags, const char *mbextra, int *cerr_ptr)
533 {
534 	return istrsenvisx(mbdst, dlen, mbsrc,
535 	    mbsrc != NULL ? strlen(mbsrc) : 0, flags, mbextra, cerr_ptr);
536 }
537 
538 #endif
539 
540 #if !HAVE_SVIS
541 /*
542  *	The "svis" variants all take an "extra" arg that is a pointer
543  *	to a NUL-terminated list of characters to be encoded, too.
544  *	These functions are useful e. g. to encode strings in such a
545  *	way so that they are not interpreted by a shell.
546  */
547 
548 char *
549 svis(char *mbdst, int c, int flags, int nextc, const char *mbextra)
550 {
551 	char cc[2];
552 	int ret;
553 
554 	cc[0] = c;
555 	cc[1] = nextc;
556 
557 	ret = istrsenvisx(mbdst, NULL, cc, 1, flags, mbextra, NULL);
558 	if (ret < 0)
559 		return NULL;
560 	return mbdst + ret;
561 }
562 
563 char *
564 snvis(char *mbdst, size_t dlen, int c, int flags, int nextc, const char *mbextra)
565 {
566 	char cc[2];
567 	int ret;
568 
569 	cc[0] = c;
570 	cc[1] = nextc;
571 
572 	ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, mbextra, NULL);
573 	if (ret < 0)
574 		return NULL;
575 	return mbdst + ret;
576 }
577 
578 int
579 strsvis(char *mbdst, const char *mbsrc, int flags, const char *mbextra)
580 {
581 	return istrsenvisxl(mbdst, NULL, mbsrc, flags, mbextra, NULL);
582 }
583 
584 int
585 strsnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags, const char *mbextra)
586 {
587 	return istrsenvisxl(mbdst, &dlen, mbsrc, flags, mbextra, NULL);
588 }
589 
590 int
591 strsvisx(char *mbdst, const char *mbsrc, size_t len, int flags, const char *mbextra)
592 {
593 	return istrsenvisx(mbdst, NULL, mbsrc, len, flags, mbextra, NULL);
594 }
595 
596 int
597 strsnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
598     const char *mbextra)
599 {
600 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, NULL);
601 }
602 
603 int
604 strsenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
605     const char *mbextra, int *cerr_ptr)
606 {
607 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, cerr_ptr);
608 }
609 #endif
610 
611 #if !HAVE_VIS
612 /*
613  * vis - visually encode characters
614  */
615 char *
616 vis(char *mbdst, int c, int flags, int nextc)
617 {
618 	char cc[2];
619 	int ret;
620 
621 	cc[0] = c;
622 	cc[1] = nextc;
623 
624 	ret = istrsenvisx(mbdst, NULL, cc, 1, flags, "", NULL);
625 	if (ret < 0)
626 		return NULL;
627 	return mbdst + ret;
628 }
629 
630 char *
631 nvis(char *mbdst, size_t dlen, int c, int flags, int nextc)
632 {
633 	char cc[2];
634 	int ret;
635 
636 	cc[0] = c;
637 	cc[1] = nextc;
638 
639 	ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, "", NULL);
640 	if (ret < 0)
641 		return NULL;
642 	return mbdst + ret;
643 }
644 
645 /*
646  * strvis - visually encode characters from src into dst
647  *
648  *	Dst must be 4 times the size of src to account for possible
649  *	expansion.  The length of dst, not including the trailing NULL,
650  *	is returned.
651  */
652 
653 int
654 strvis(char *mbdst, const char *mbsrc, int flags)
655 {
656 	return istrsenvisxl(mbdst, NULL, mbsrc, flags, "", NULL);
657 }
658 
659 int
660 strnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags)
661 {
662 	return istrsenvisxl(mbdst, &dlen, mbsrc, flags, "", NULL);
663 }
664 
665 /*
666  * strvisx - visually encode characters from src into dst
667  *
668  *	Dst must be 4 times the size of src to account for possible
669  *	expansion.  The length of dst, not including the trailing NULL,
670  *	is returned.
671  *
672  *	Strvisx encodes exactly len characters from src into dst.
673  *	This is useful for encoding a block of data.
674  */
675 
676 int
677 strvisx(char *mbdst, const char *mbsrc, size_t len, int flags)
678 {
679 	return istrsenvisx(mbdst, NULL, mbsrc, len, flags, "", NULL);
680 }
681 
682 int
683 strnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags)
684 {
685 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", NULL);
686 }
687 
688 int
689 strenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
690     int *cerr_ptr)
691 {
692 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", cerr_ptr);
693 }
694 #endif
695