lib/libc/gen/vis.c

   1 /*      $NetBSD: vis.c,v 1.60 2013/02/21 16:21:20 joerg 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 1.60 2013/02/21 16:21:20 joerg 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 #if !defined(__NetBSD__) && ! defined(__minix)
 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);
 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 (!mblength)
 379                 mblength = strlen(mbsrc);
 380         if ((psrc = calloc(mblength + 1, sizeof(*psrc))) == NULL)
 381                 return -1;
 382         if ((pdst = calloc((4 * mblength) + 1, sizeof(*pdst))) == NULL)
 383                 goto out;
 384         dst = pdst;
 385         src = psrc;
 386
 387         /* Use caller's multibyte conversion error flag. */
 388         if (cerr_ptr)
 389                 cerr = *cerr_ptr;
 390
 391         /*
 392          * Input loop.
 393          * Handle up to mblength characters (not bytes).  We do not
 394          * stop at NULs because we may be processing a block of data
 395          * that includes NULs.
 396          */
 397         mbslength = (ssize_t)mblength;
 398         /*
 399          * When inputing a single character, must also read in the
 400          * next character for nextc, the look-ahead character.
 401          */
 402         if (mbslength == 1)
 403                 mbslength++;
 404         while (mbslength > 0) {
 405                 /* Convert one multibyte character to wchar_t. */
 406                 if (!cerr)
 407                         clen = mbtowc(src, mbsrc, MB_LEN_MAX);
 408                 if (cerr || clen < 0) {
 409                         /* Conversion error, process as a byte instead. */
 410                         *src = (wint_t)(u_char)*mbsrc;
 411                         clen = 1;
 412                         cerr = 1;
 413                 }
 414                 if (clen == 0)
 415                         /*
 416                          * NUL in input gives 0 return value. process
 417                          * as single NUL byte and keep going.
 418                          */
 419                         clen = 1;
 420                 /* Advance buffer character pointer. */
 421                 src++;
 422                 /* Advance input pointer by number of bytes read. */
 423                 mbsrc += clen;
 424                 /* Decrement input byte count. */
 425                 mbslength -= clen;
 426         }
 427         len = src - psrc;
 428         src = psrc;
 429         /*
 430          * In the single character input case, we will have actually
 431          * processed two characters, c and nextc.  Reset len back to
 432          * just a single character.
 433          */
 434         if (mblength < len)
 435                 len = mblength;
 436
 437         /* Convert extra argument to list of characters for this mode. */
 438         extra = makeextralist(flags, mbextra);
 439         if (!extra) {
 440                 if (dlen && *dlen == 0) {
 441                         errno = ENOSPC;
 442                         goto out;
 443                 }
 444                 *mbdst = '\0';          /* can't create extra, return "" */
 445                 error = 0;
 446                 goto out;
 447         }
 448
 449         /* Look up which processing function to call. */
 450         f = getvisfun(flags);
 451
 452         /*
 453          * Main processing loop.
 454          * Call do_Xvis processing function one character at a time
 455          * with next character available for look-ahead.
 456          */
 457         for (start = dst; len > 0; len--) {
 458                 c = *src++;
 459                 dst = (*f)(dst, c, flags, len >= 1 ? *src : L'\0', extra);
 460                 if (dst == NULL) {
 461                         errno = ENOSPC;
 462                         goto out;
 463                 }
 464         }
 465
 466         /* Terminate the string in the buffer. */
 467         *dst = L'\0';
 468
 469         /*
 470          * Output loop.
 471          * Convert wchar_t string back to multibyte output string.
 472          * If we have hit a multi-byte conversion error on input,
 473          * output byte-by-byte here.  Else use wctomb().
 474          */
 475         len = wcslen(start);
 476         maxolen = dlen ? *dlen : (wcslen(start) * MB_LEN_MAX + 1);
 477         olen = 0;
 478         for (dst = start; len > 0; len--) {
 479                 if (!cerr)
 480                         clen = wctomb(mbdst, *dst);
 481                 if (cerr || clen < 0) {
 482                         /*
 483                          * Conversion error, process as a byte(s) instead.
 484                          * Examine each byte and higher-order bytes for
 485                          * data.  E.g.,
 486                          *      0x000000000000a264 -> a2 64
 487                          *      0x000000001f00a264 -> 1f 00 a2 64
 488                          */
 489                         clen = 0;
 490                         wmsk = 0;
 491                         for (i = sizeof(wmsk) - 1; i >= 0; i--) {
 492                                 shft = i * NBBY;
 493                                 bmsk = (uint64_t)0xffLL << shft;
 494                                 wmsk |= bmsk;
 495                                 if ((*dst & wmsk) || i == 0)
 496                                         mbdst[clen++] = (char)(
 497                                             (uint64_t)(*dst & bmsk) >>
 498                                             shft);
 499                         }
 500                         cerr = 1;
 501                 }
 502                 /* If this character would exceed our output limit, stop. */
 503                 if (olen + clen > (size_t)maxolen)
 504                         break;
 505                 /* Advance output pointer by number of bytes written. */
 506                 mbdst += clen;
 507                 /* Advance buffer character pointer. */
 508                 dst++;
 509                 /* Incrment output character count. */
 510                 olen += clen;
 511         }
 512
 513         /* Terminate the output string. */
 514         *mbdst = '\0';
 515
 516         /* Pass conversion error flag out. */
 517         if (cerr_ptr)
 518                 *cerr_ptr = cerr;
 519
 520         free(extra);
 521         free(pdst);
 522         free(psrc);
 523
 524         return (int)olen;
 525 out:
 526         free(extra);
 527         free(pdst);
 528         free(psrc);
 529         return error;
 530 }
 531 #endif
 532
 533 #if !HAVE_SVIS
 534 /*
 535  *      The "svis" variants all take an "extra" arg that is a pointer
 536  *      to a NUL-terminated list of characters to be encoded, too.
 537  *      These functions are useful e. g. to encode strings in such a
 538  *      way so that they are not interpreted by a shell.
 539  */
 540
 541 char *
 542 svis(char *mbdst, int c, int flags, int nextc, const char *mbextra)
 543 {
 544         char cc[2];
 545         int ret;
 546
 547         cc[0] = c;
 548         cc[1] = nextc;
 549
 550         ret = istrsenvisx(mbdst, NULL, cc, 1, flags, mbextra, NULL);
 551         if (ret < 0)
 552                 return NULL;
 553         return mbdst + ret;
 554 }
 555
 556 char *
 557 snvis(char *mbdst, size_t dlen, int c, int flags, int nextc, const char *mbextra)
 558 {
 559         char cc[2];
 560         int ret;
 561
 562         cc[0] = c;
 563         cc[1] = nextc;
 564
 565         ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, mbextra, NULL);
 566         if (ret < 0)
 567                 return NULL;
 568         return mbdst + ret;
 569 }
 570
 571 int
 572 strsvis(char *mbdst, const char *mbsrc, int flags, const char *mbextra)
 573 {
 574         return istrsenvisx(mbdst, NULL, mbsrc, 0, flags, mbextra, NULL);
 575 }
 576
 577 int
 578 strsnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags, const char *mbextra)
 579 {
 580         return istrsenvisx(mbdst, &dlen, mbsrc, 0, flags, mbextra, NULL);
 581 }
 582
 583 int
 584 strsvisx(char *mbdst, const char *mbsrc, size_t len, int flags, const char *mbextra)
 585 {
 586         return istrsenvisx(mbdst, NULL, mbsrc, len, flags, mbextra, NULL);
 587 }
 588
 589 int
 590 strsnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
 591     const char *mbextra)
 592 {
 593         return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, NULL);
 594 }
 595
 596 int
 597 strsenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
 598     const char *mbextra, int *cerr_ptr)
 599 {
 600         return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, cerr_ptr);
 601 }
 602 #endif
 603
 604 #if !HAVE_VIS
 605 /*
 606  * vis - visually encode characters
 607  */
 608 char *
 609 vis(char *mbdst, int c, int flags, int nextc)
 610 {
 611         char cc[2];
 612         int ret;
 613
 614         cc[0] = c;
 615         cc[1] = nextc;
 616
 617         ret = istrsenvisx(mbdst, NULL, cc, 1, flags, "", NULL);
 618         if (ret < 0)
 619                 return NULL;
 620         return mbdst + ret;
 621 }
 622
 623 char *
 624 nvis(char *mbdst, size_t dlen, int c, int flags, int nextc)
 625 {
 626         char cc[2];
 627         int ret;
 628
 629         cc[0] = c;
 630         cc[1] = nextc;
 631
 632         ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, "", NULL);
 633         if (ret < 0)
 634                 return NULL;
 635         return mbdst + ret;
 636 }
 637
 638 /*
 639  * strvis - visually encode characters from src into dst
 640  *
 641  *      Dst must be 4 times the size of src to account for possible
 642  *      expansion.  The length of dst, not including the trailing NULL,
 643  *      is returned.
 644  */
 645
 646 int
 647 strvis(char *mbdst, const char *mbsrc, int flags)
 648 {
 649         return istrsenvisx(mbdst, NULL, mbsrc, 0, flags, "", NULL);
 650 }
 651
 652 int
 653 strnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags)
 654 {
 655         return istrsenvisx(mbdst, &dlen, mbsrc, 0, flags, "", NULL);
 656 }
 657
 658 /*
 659  * strvisx - visually encode characters from src into dst
 660  *
 661  *      Dst must be 4 times the size of src to account for possible
 662  *      expansion.  The length of dst, not including the trailing NULL,
 663  *      is returned.
 664  *
 665  *      Strvisx encodes exactly len characters from src into dst.
 666  *      This is useful for encoding a block of data.
 667  */
 668
 669 int
 670 strvisx(char *mbdst, const char *mbsrc, size_t len, int flags)
 671 {
 672         return istrsenvisx(mbdst, NULL, mbsrc, len, flags, "", NULL);
 673 }
 674
 675 int
 676 strnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags)
 677 {
 678         return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", NULL);
 679 }
 680
 681 int
 682 strenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
 683     int *cerr_ptr)
 684 {
 685         return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", cerr_ptr);
 686 }
 687 #endif