1 /*        $NetBSD: vis.c,v 1.88 2024/03/17 21:48:02 andvar 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 1.88 2024/03/17 21:48:02 andvar 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 
69 #include <sys/param.h>
70 #include <sys/types.h>
71 
72 #include <assert.h>
73 #include <errno.h>
74 #include <stdint.h>
75 #include <stdlib.h>
76 #include <vis.h>
77 #include <wchar.h>
78 #include <wctype.h>
79 
80 #ifdef __weak_alias
81 __weak_alias(strvisx,_strvisx)
82 #endif
83 
84 #if !HAVE_VIS || !HAVE_SVIS
85 #include <ctype.h>
86 #include <limits.h>
87 #include <stdio.h>
88 #include <string.h>
89 
90 /*
91  * The reason for going through the trouble to deal with character encodings
92  * in vis(3), is that we use this to safe encode output of commands. This
93  * safe encoding varies depending on the character set. For example if we
94  * display ps output in French, we don't want to display French characters
95  * as M-foo.
96  */
97 
98 static wchar_t *do_svis(wchar_t *, wint_t, int, wint_t, const wchar_t *);
99 
100 #undef BELL
101 #define BELL L'\a'
102 
103 #if defined(LC_C_LOCALE)
104 #define iscgraph(c)      isgraph_l(c, LC_C_LOCALE)
105 #else
106 /* Keep it simple for now, no locale stuff */
107 #define iscgraph(c) isgraph(c)
108 #ifdef notyet
109 #include <locale.h>
110 static int
iscgraph(int c)111 iscgraph(int c) {
112           int rv;
113           char *ol;
114 
115           ol = setlocale(LC_CTYPE, "C");
116           rv = isgraph(c);
117           if (ol)
118                     setlocale(LC_CTYPE, ol);
119           return rv;
120 }
121 #endif
122 #endif
123 
124 #define ISGRAPH(flags, c) \
125     (((flags) & VIS_NOLOCALE) ? iscgraph(c) : iswgraph(c))
126 
127 #define iswoctal(c) (((u_char)(c)) >= L'0' && ((u_char)(c)) <= L'7')
128 #define iswwhite(c) (c == L' ' || c == L'\t' || c == L'\n')
129 #define iswsafe(c)  (c == L'\b' || c == BELL || c == L'\r')
130 #define xtoa(c)               L"0123456789abcdef"[c]
131 #define XTOA(c)               L"0123456789ABCDEF"[c]
132 
133 #define MAXEXTRAS   30
134 
135 static const wchar_t char_shell[] = L"'`\";&<>()|{}]\\$!^~";
136 static const wchar_t char_glob[] = L"*?[#";
137 
138 #if !HAVE_NBTOOL_CONFIG_H
139 #ifndef __NetBSD__
140 /*
141  * On NetBSD MB_LEN_MAX is currently 32 which does not fit on any integer
142  * integral type and it is probably wrong, since currently the maximum
143  * number of bytes and character needs is 6. Until this is fixed, the
144  * loops below are using sizeof(uint64_t) - 1 instead of MB_LEN_MAX, and
145  * the assertion is commented out.
146  */
147 #ifdef __FreeBSD__
148 /*
149  * On FreeBSD including <sys/systm.h> for CTASSERT only works in kernel
150  * mode.
151  */
152 #ifndef CTASSERT
153 #define CTASSERT(x)             _CTASSERT(x, __LINE__)
154 #define _CTASSERT(x, y)         __CTASSERT(x, y)
155 #define __CTASSERT(x, y)        typedef char __assert ## y[(x) ? 1 : -1]
156 #endif
157 #endif /* __FreeBSD__ */
158 CTASSERT(MB_LEN_MAX <= sizeof(uint64_t));
159 #endif /* !__NetBSD__ */
160 #endif
161 
162 /*
163  * This is do_hvis, for HTTP style (RFC 1808)
164  */
165 static wchar_t *
do_hvis(wchar_t * dst,wint_t c,int flags,wint_t nextc,const wchar_t * extra)166 do_hvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
167 {
168           if (iswalnum(c)
169               /* safe */
170               || c == L'$' || c == L'-' || c == L'_' || c == L'.' || c == L'+'
171               /* extra */
172               || c == L'!' || c == L'*' || c == L'\'' || c == L'(' || c == L')'
173               || c == L',')
174                     dst = do_svis(dst, c, flags, nextc, extra);
175           else {
176                     *dst++ = L'%';
177                     *dst++ = xtoa(((unsigned int)c >> 4) & 0xf);
178                     *dst++ = xtoa((unsigned int)c & 0xf);
179           }
180 
181           return dst;
182 }
183 
184 /*
185  * This is do_mvis, for Quoted-Printable MIME (RFC 2045)
186  * NB: No handling of long lines or CRLF.
187  */
188 static wchar_t *
do_mvis(wchar_t * dst,wint_t c,int flags,wint_t nextc,const wchar_t * extra)189 do_mvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
190 {
191           if ((c != L'\n') &&
192               /* Space at the end of the line */
193               ((iswspace(c) && (nextc == L'\r' || nextc == L'\n')) ||
194               /* Out of range */
195               (!iswspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) ||
196               /* Specific char to be escaped */
197               wcschr(L"#$@[\\]^`{|}~", c) != NULL)) {
198                     *dst++ = L'=';
199                     *dst++ = XTOA(((unsigned int)c >> 4) & 0xf);
200                     *dst++ = XTOA((unsigned int)c & 0xf);
201           } else
202                     dst = do_svis(dst, c, flags, nextc, extra);
203           return dst;
204 }
205 
206 /*
207  * Output single byte of multibyte character.
208  */
209 static wchar_t *
do_mbyte(wchar_t * dst,wint_t c,int flags,wint_t nextc,int iswextra)210 do_mbyte(wchar_t *dst, wint_t c, int flags, wint_t nextc, int iswextra)
211 {
212           if (flags & VIS_CSTYLE) {
213                     switch (c) {
214                     case L'\n':
215                               *dst++ = L'\\'; *dst++ = L'n';
216                               return dst;
217                     case L'\r':
218                               *dst++ = L'\\'; *dst++ = L'r';
219                               return dst;
220                     case L'\b':
221                               *dst++ = L'\\'; *dst++ = L'b';
222                               return dst;
223                     case BELL:
224                               *dst++ = L'\\'; *dst++ = L'a';
225                               return dst;
226                     case L'\v':
227                               *dst++ = L'\\'; *dst++ = L'v';
228                               return dst;
229                     case L'\t':
230                               *dst++ = L'\\'; *dst++ = L't';
231                               return dst;
232                     case L'\f':
233                               *dst++ = L'\\'; *dst++ = L'f';
234                               return dst;
235                     case L' ':
236                               *dst++ = L'\\'; *dst++ = L's';
237                               return dst;
238                     case L'\0':
239                               *dst++ = L'\\'; *dst++ = L'0';
240                               if (iswoctal(nextc)) {
241                                         *dst++ = L'0';
242                                         *dst++ = L'0';
243                               }
244                               return dst;
245                     /* We cannot encode these characters in VIS_CSTYLE
246                      * because they special meaning */
247                     case L'n':
248                     case L'r':
249                     case L'b':
250                     case L'a':
251                     case L'v':
252                     case L't':
253                     case L'f':
254                     case L's':
255                     case L'0':
256                     case L'M':
257                     case L'^':
258                     case L'$': /* vis(1) -l */
259                               break;
260                     default:
261                               if (ISGRAPH(flags, c) && !iswoctal(c)) {
262                                         *dst++ = L'\\';
263                                         *dst++ = c;
264                                         return dst;
265                               }
266                     }
267           }
268           if (iswextra || ((c & 0177) == L' ') || (flags & VIS_OCTAL)) {
269                     *dst++ = L'\\';
270                     *dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + L'0';
271                     *dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + L'0';
272                     *dst++ =                           (c         & 07) + L'0';
273           } else {
274                     if ((flags & VIS_NOSLASH) == 0)
275                               *dst++ = L'\\';
276 
277                     if (c & 0200) {
278                               c &= 0177;
279                               *dst++ = L'M';
280                     }
281 
282                     if (iswcntrl(c)) {
283                               *dst++ = L'^';
284                               if (c == 0177)
285                                         *dst++ = L'?';
286                               else
287                                         *dst++ = c + L'@';
288                     } else {
289                               *dst++ = L'-';
290                               *dst++ = c;
291                     }
292           }
293 
294           return dst;
295 }
296 
297 /*
298  * This is do_vis, the central code of vis.
299  * dst:         Pointer to the destination buffer
300  * c:           Character to encode
301  * flags:     Flags word
302  * nextc:     The character following 'c'
303  * extra:     Pointer to the list of extra characters to be
304  *              backslash-protected.
305  */
306 static wchar_t *
do_svis(wchar_t * dst,wint_t c,int flags,wint_t nextc,const wchar_t * extra)307 do_svis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
308 {
309           int iswextra, i, shft;
310           uint64_t bmsk, wmsk;
311 
312           iswextra = wcschr(extra, c) != NULL;
313           if (!iswextra && (ISGRAPH(flags, c) || iswwhite(c) ||
314               ((flags & VIS_SAFE) && iswsafe(c)))) {
315                     *dst++ = c;
316                     return dst;
317           }
318 
319           /* See comment in istrsenvisx() output loop, below. */
320           wmsk = 0;
321           for (i = sizeof(wmsk) - 1; i >= 0; i--) {
322                     shft = i * NBBY;
323                     bmsk = (uint64_t)0xffLL << shft;
324                     wmsk |= bmsk;
325                     if ((c & wmsk) || i == 0)
326                               dst = do_mbyte(dst, (wint_t)(
327                                   (uint64_t)(c & bmsk) >> shft),
328                                   flags, nextc, iswextra);
329           }
330 
331           return dst;
332 }
333 
334 typedef wchar_t *(*visfun_t)(wchar_t *, wint_t, int, wint_t, const wchar_t *);
335 
336 /*
337  * Return the appropriate encoding function depending on the flags given.
338  */
339 static visfun_t
getvisfun(int flags)340 getvisfun(int flags)
341 {
342           if (flags & VIS_HTTPSTYLE)
343                     return do_hvis;
344           if (flags & VIS_MIMESTYLE)
345                     return do_mvis;
346           return do_svis;
347 }
348 
349 /*
350  * Expand list of extra characters to not visually encode.
351  */
352 static wchar_t *
makeextralist(int flags,const char * src)353 makeextralist(int flags, const char *src)
354 {
355           wchar_t *dst, *d;
356           size_t len;
357           const wchar_t *s;
358           mbstate_t mbstate;
359 
360           len = strlen(src);
361           if ((dst = calloc(len + MAXEXTRAS, sizeof(*dst))) == NULL)
362                     return NULL;
363 
364           memset(&mbstate, 0, sizeof(mbstate));
365           if ((flags & VIS_NOLOCALE)
366               || mbsrtowcs(dst, &src, len, &mbstate) == (size_t)-1) {
367                     size_t i;
368                     for (i = 0; i < len; i++)
369                               dst[i] = (wchar_t)(u_char)src[i];
370                     d = dst + len;
371           } else
372                     d = dst + wcslen(dst);
373 
374           if (flags & VIS_GLOB)
375                     for (s = char_glob; *s; *d++ = *s++)
376                               continue;
377 
378           if (flags & VIS_SHELL)
379                     for (s = char_shell; *s; *d++ = *s++)
380                               continue;
381 
382           if (flags & VIS_SP) *d++ = L' ';
383           if (flags & VIS_TAB) *d++ = L'\t';
384           if (flags & VIS_NL) *d++ = L'\n';
385           if (flags & VIS_DQ) *d++ = L'"';
386           if ((flags & VIS_NOSLASH) == 0) *d++ = L'\\';
387           *d = L'\0';
388 
389           return dst;
390 }
391 
392 /*
393  * istrsenvisx()
394  *        The main internal function.
395  *        All user-visible functions call this one.
396  */
397 static int
istrsenvisx(char ** mbdstp,size_t * dlen,const char * mbsrc,size_t mblength,int flags,const char * mbextra,int * cerr_ptr)398 istrsenvisx(char **mbdstp, size_t *dlen, const char *mbsrc, size_t mblength,
399     int flags, const char *mbextra, int *cerr_ptr)
400 {
401           char mbbuf[MB_LEN_MAX];
402           wchar_t *dst, *src, *pdst, *psrc, *start, *extra;
403           size_t len, olen;
404           uint64_t bmsk, wmsk;
405           wint_t c;
406           visfun_t f;
407           int cerr, error = -1, i, shft;
408           ssize_t clen = 0;
409           char *mbdst, *mbwrite, *mdst;
410           size_t mbslength;
411           size_t maxolen;
412           mbstate_t mbstate;
413 
414           _DIAGASSERT(mbdstp != NULL);
415           _DIAGASSERT(mbsrc != NULL || mblength == 0);
416           _DIAGASSERT(mbextra != NULL);
417 
418           mbslength = mblength;
419           /*
420            * When inputing a single character, must also read in the
421            * next character for nextc, the look-ahead character.
422            */
423           if (mbslength == 1)
424                     mbslength++;
425 
426           /*
427            * Input (mbsrc) is a char string considered to be multibyte
428            * characters.  The input loop will read this string pulling
429            * one character, possibly multiple bytes, from mbsrc and
430            * converting each to wchar_t in src.
431            *
432            * The vis conversion will be done using the wide char
433            * wchar_t string.
434            *
435            * This will then be converted back to a multibyte string to
436            * return to the caller.
437            */
438 
439           /*
440            * Guarantee the arithmetic on input to calloc won't overflow.
441            */
442           if (mbslength > (SIZE_MAX - 1)/16) {
443                     errno = ENOMEM;
444                     return -1;
445           }
446 
447           /* Allocate space for the wide char strings */
448           psrc = pdst = extra = NULL;
449           mdst = NULL;
450           if ((psrc = calloc(mbslength + 1, sizeof(*psrc))) == NULL)
451                     return -1;
452           if ((pdst = calloc((16 * mbslength) + 1, sizeof(*pdst))) == NULL)
453                     goto out;
454           if (*mbdstp == NULL) {
455                     if ((mdst = calloc((16 * mbslength) + 1, sizeof(*mdst))) == NULL)
456                               goto out;
457                     *mbdstp = mdst;
458           }
459 
460           mbdst = *mbdstp;
461           dst = pdst;
462           src = psrc;
463 
464           if (flags & VIS_NOLOCALE) {
465                     /* Do one byte at a time conversion */
466                     cerr = 1;
467           } else {
468                     /* Use caller's multibyte conversion error flag. */
469                     cerr = cerr_ptr ? *cerr_ptr : 0;
470           }
471 
472           /*
473            * Input loop.
474            * Handle up to mblength characters (not bytes).  We do not
475            * stop at NULs because we may be processing a block of data
476            * that includes NULs.
477            */
478           memset(&mbstate, 0, sizeof(mbstate));
479           while (mbslength > 0) {
480                     /* Convert one multibyte character to wchar_t. */
481                     if (!cerr) {
482                               clen = (ssize_t)mbrtowc(src, mbsrc,
483                                   (mbslength < MB_LEN_MAX
484                                         ? mbslength
485                                         : MB_LEN_MAX),
486                                   &mbstate);
487                               assert(clen < 0 || (size_t)clen <= mbslength);
488                               assert(clen <= MB_LEN_MAX);
489                     }
490                     if (cerr || clen < 0) {
491                               /* Conversion error, process as a byte instead. */
492                               *src = (wint_t)(u_char)*mbsrc;
493                               clen = 1;
494                               cerr = 1;
495                     }
496                     if (clen == 0) {
497                               /*
498                                * NUL in input gives 0 return value. process
499                                * as single NUL byte and keep going.
500                                */
501                               clen = 1;
502                     }
503                     /*
504                      * Let n := MIN(mbslength, MB_LEN_MAX).  We have:
505                      *
506                      *        mbslength >= 1
507                      *        mbrtowc(..., n, &mbstate) <= n,
508                      *                  by the contract of mbrtowc
509                      *
510                      *  clen is either
511                      *  (a) mbrtowc(..., n, &mbstate), in which case
512                      *      clen <= n <= mbslength; or
513                      *  (b) 1, in which case clen = 1 <= mbslength.
514                      */
515                     assert(clen > 0);
516                     assert((size_t)clen <= mbslength);
517                     /* Advance buffer character pointer. */
518                     src++;
519                     /* Advance input pointer by number of bytes read. */
520                     mbsrc += clen;
521                     /* Decrement input byte count. */
522                     mbslength -= clen;
523           }
524           len = src - psrc;
525           src = psrc;
526 
527           /*
528            * In the single character input case, we will have actually
529            * processed two characters, c and nextc.  Reset len back to
530            * just a single character.
531            */
532           if (mblength < len)
533                     len = mblength;
534 
535           /* Convert extra argument to list of characters for this mode. */
536           extra = makeextralist(flags, mbextra);
537           if (!extra) {
538                     if (dlen && *dlen == 0) {
539                               errno = ENOSPC;
540                               goto out;
541                     }
542                     *mbdst = '\0';      /* can't create extra, return "" */
543                     error = 0;
544                     goto out;
545           }
546 
547           /* Look up which processing function to call. */
548           f = getvisfun(flags);
549 
550           /*
551            * Main processing loop.
552            * Call do_Xvis processing function one character at a time
553            * with next character available for look-ahead.
554            */
555           for (start = dst; len > 0; len--) {
556                     c = *src++;
557                     dst = (*f)(dst, c, flags, len >= 1 ? *src : L'\0', extra);
558                     if (dst == NULL) {
559                               errno = ENOSPC;
560                               goto out;
561                     }
562           }
563 
564           /* Terminate the string in the buffer. */
565           *dst = L'\0';
566 
567           /*
568            * Output loop.
569            * Convert wchar_t string back to multibyte output string.
570            * If we have hit a multi-byte conversion error on input,
571            * output byte-by-byte here.  Else use wctomb().
572            */
573           len = wcslen(start);
574           if (dlen) {
575                     maxolen = *dlen;
576                     if (maxolen == 0) {
577                               errno = ENOSPC;
578                               goto out;
579                     }
580           } else {
581                     if (len > (SIZE_MAX - 1)/MB_LEN_MAX) {
582                               errno = ENOSPC;
583                               goto out;
584                     }
585                     maxolen = len*MB_LEN_MAX + 1;
586           }
587           olen = 0;
588           memset(&mbstate, 0, sizeof(mbstate));
589           for (dst = start; len > 0; len--) {
590                     if (!cerr) {
591                               /*
592                                * If we have at least MB_CUR_MAX bytes in the buffer,
593                                * we'll just do the conversion in-place into mbdst.  We
594                                * need to be a little more conservative when we get to
595                                * the end of the buffer, as we may not have MB_CUR_MAX
596                                * bytes but we may not need it.
597                                */
598                               if (maxolen - olen > MB_CUR_MAX)
599                                         mbwrite = mbdst;
600                               else
601                                         mbwrite = mbbuf;
602                               clen = (ssize_t)wcrtomb(mbwrite, *dst, &mbstate);
603                               if (clen > 0 && mbwrite != mbdst) {
604                                         /*
605                                          * Don't break past our output limit, noting
606                                          * that maxolen includes the nul terminator so
607                                          * we can't write past maxolen - 1 here.
608                                          */
609                                         if (olen + clen >= maxolen) {
610                                                   errno = ENOSPC;
611                                                   goto out;
612                                         }
613 
614                                         memcpy(mbdst, mbwrite, clen);
615                               }
616                     }
617                     if (cerr || clen < 0) {
618                               /*
619                                * Conversion error, process as a byte(s) instead.
620                                * Examine each byte and higher-order bytes for
621                                * data.  E.g.,
622                                *        0x000000000000a264 -> a2 64
623                                *        0x000000001f00a264 -> 1f 00 a2 64
624                                */
625                               clen = 0;
626                               wmsk = 0;
627                               for (i = sizeof(wmsk) - 1; i >= 0; i--) {
628                                         shft = i * NBBY;
629                                         bmsk = (uint64_t)0xffLL << shft;
630                                         wmsk |= bmsk;
631                                         if ((*dst & wmsk) || i == 0) {
632                                                   if (olen + clen + 1 >= maxolen) {
633                                                             errno = ENOSPC;
634                                                             goto out;
635                                                   }
636 
637                                                   mbdst[clen++] = (char)(
638                                                       (uint64_t)(*dst & bmsk) >>
639                                                       shft);
640                                         }
641                               }
642                               cerr = 1;
643                     }
644 
645                     /*
646                      * We'll be dereferencing mbdst[clen] after this to write the
647                      * nul terminator; the above paths should have checked for a
648                      * possible overflow already.
649                      */
650                     assert(olen + clen < maxolen);
651 
652                     /* Advance output pointer by number of bytes written. */
653                     mbdst += clen;
654                     /* Advance buffer character pointer. */
655                     dst++;
656                     /* Increment output character count. */
657                     olen += clen;
658           }
659 
660           /* Terminate the output string. */
661           assert(olen < maxolen);
662           *mbdst = '\0';
663 
664           if (flags & VIS_NOLOCALE) {
665                     /* Pass conversion error flag out. */
666                     if (cerr_ptr)
667                               *cerr_ptr = cerr;
668           }
669 
670           free(extra);
671           free(pdst);
672           free(psrc);
673 
674           return (int)olen;
675 out:
676           free(extra);
677           free(pdst);
678           free(psrc);
679           free(mdst);
680           return error;
681 }
682 
683 static int
istrsenvisxl(char ** mbdstp,size_t * dlen,const char * mbsrc,int flags,const char * mbextra,int * cerr_ptr)684 istrsenvisxl(char **mbdstp, size_t *dlen, const char *mbsrc,
685     int flags, const char *mbextra, int *cerr_ptr)
686 {
687           return istrsenvisx(mbdstp, dlen, mbsrc,
688               mbsrc != NULL ? strlen(mbsrc) : 0, flags, mbextra, cerr_ptr);
689 }
690 
691 #endif
692 
693 #if !HAVE_SVIS
694 /*
695  *        The "svis" variants all take an "extra" arg that is a pointer
696  *        to a NUL-terminated list of characters to be encoded, too.
697  *        These functions are useful e. g. to encode strings in such a
698  *        way so that they are not interpreted by a shell.
699  */
700 
701 char *
svis(char * mbdst,int c,int flags,int nextc,const char * mbextra)702 svis(char *mbdst, int c, int flags, int nextc, const char *mbextra)
703 {
704           char cc[2];
705           int ret;
706 
707           cc[0] = c;
708           cc[1] = nextc;
709 
710           ret = istrsenvisx(&mbdst, NULL, cc, 1, flags, mbextra, NULL);
711           if (ret < 0)
712                     return NULL;
713           return mbdst + ret;
714 }
715 
716 char *
snvis(char * mbdst,size_t dlen,int c,int flags,int nextc,const char * mbextra)717 snvis(char *mbdst, size_t dlen, int c, int flags, int nextc, const char *mbextra)
718 {
719           char cc[2];
720           int ret;
721 
722           cc[0] = c;
723           cc[1] = nextc;
724 
725           ret = istrsenvisx(&mbdst, &dlen, cc, 1, flags, mbextra, NULL);
726           if (ret < 0)
727                     return NULL;
728           return mbdst + ret;
729 }
730 
731 int
strsvis(char * mbdst,const char * mbsrc,int flags,const char * mbextra)732 strsvis(char *mbdst, const char *mbsrc, int flags, const char *mbextra)
733 {
734           return istrsenvisxl(&mbdst, NULL, mbsrc, flags, mbextra, NULL);
735 }
736 
737 int
strsnvis(char * mbdst,size_t dlen,const char * mbsrc,int flags,const char * mbextra)738 strsnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags, const char *mbextra)
739 {
740           return istrsenvisxl(&mbdst, &dlen, mbsrc, flags, mbextra, NULL);
741 }
742 
743 int
strsvisx(char * mbdst,const char * mbsrc,size_t len,int flags,const char * mbextra)744 strsvisx(char *mbdst, const char *mbsrc, size_t len, int flags, const char *mbextra)
745 {
746           return istrsenvisx(&mbdst, NULL, mbsrc, len, flags, mbextra, NULL);
747 }
748 
749 int
strsnvisx(char * mbdst,size_t dlen,const char * mbsrc,size_t len,int flags,const char * mbextra)750 strsnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
751     const char *mbextra)
752 {
753           return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, mbextra, NULL);
754 }
755 
756 int
strsenvisx(char * mbdst,size_t dlen,const char * mbsrc,size_t len,int flags,const char * mbextra,int * cerr_ptr)757 strsenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
758     const char *mbextra, int *cerr_ptr)
759 {
760           return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, mbextra, cerr_ptr);
761 }
762 #endif
763 
764 #if !HAVE_VIS
765 /*
766  * vis - visually encode characters
767  */
768 char *
vis(char * mbdst,int c,int flags,int nextc)769 vis(char *mbdst, int c, int flags, int nextc)
770 {
771           char cc[2];
772           int ret;
773 
774           cc[0] = c;
775           cc[1] = nextc;
776 
777           ret = istrsenvisx(&mbdst, NULL, cc, 1, flags, "", NULL);
778           if (ret < 0)
779                     return NULL;
780           return mbdst + ret;
781 }
782 
783 char *
nvis(char * mbdst,size_t dlen,int c,int flags,int nextc)784 nvis(char *mbdst, size_t dlen, int c, int flags, int nextc)
785 {
786           char cc[2];
787           int ret;
788 
789           cc[0] = c;
790           cc[1] = nextc;
791 
792           ret = istrsenvisx(&mbdst, &dlen, cc, 1, flags, "", NULL);
793           if (ret < 0)
794                     return NULL;
795           return mbdst + ret;
796 }
797 
798 /*
799  * strvis - visually encode characters from src into dst
800  *
801  *        Dst must be 4 times the size of src to account for possible
802  *        expansion.  The length of dst, not including the trailing NULL,
803  *        is returned.
804  */
805 
806 int
strvis(char * mbdst,const char * mbsrc,int flags)807 strvis(char *mbdst, const char *mbsrc, int flags)
808 {
809           return istrsenvisxl(&mbdst, NULL, mbsrc, flags, "", NULL);
810 }
811 
812 int
strnvis(char * mbdst,size_t dlen,const char * mbsrc,int flags)813 strnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags)
814 {
815           return istrsenvisxl(&mbdst, &dlen, mbsrc, flags, "", NULL);
816 }
817 
818 int
stravis(char ** mbdstp,const char * mbsrc,int flags)819 stravis(char **mbdstp, const char *mbsrc, int flags)
820 {
821           *mbdstp = NULL;
822           return istrsenvisxl(mbdstp, NULL, mbsrc, flags, "", NULL);
823 }
824 
825 /*
826  * strvisx - visually encode characters from src into dst
827  *
828  *        Dst must be 4 times the size of src to account for possible
829  *        expansion.  The length of dst, not including the trailing NULL,
830  *        is returned.
831  *
832  *        Strvisx encodes exactly len characters from src into dst.
833  *        This is useful for encoding a block of data.
834  */
835 
836 int
strvisx(char * mbdst,const char * mbsrc,size_t len,int flags)837 strvisx(char *mbdst, const char *mbsrc, size_t len, int flags)
838 {
839           return istrsenvisx(&mbdst, NULL, mbsrc, len, flags, "", NULL);
840 }
841 
842 int
strnvisx(char * mbdst,size_t dlen,const char * mbsrc,size_t len,int flags)843 strnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags)
844 {
845           return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, "", NULL);
846 }
847 
848 int
strenvisx(char * mbdst,size_t dlen,const char * mbsrc,size_t len,int flags,int * cerr_ptr)849 strenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
850     int *cerr_ptr)
851 {
852           return istrsenvisx(&mbdst, &dlen, mbsrc, len, flags, "", cerr_ptr);
853 }
854 #endif
855