1 /* 2 * Copyright 2013 Garrett D'Amore <garrett@damore.org> 3 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 4 * Copyright (c) 2002-2004 Tim J. Robbins 5 * 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include "lint.h" 30 #include <errno.h> 31 #include <limits.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include <wchar.h> 35 #include "mblocal.h" 36 #include "lctype.h" 37 38 static size_t _UTF8_mbrtowc(wchar_t *_RESTRICT_KYWD, 39 const char *_RESTRICT_KYWD, 40 size_t, mbstate_t *_RESTRICT_KYWD); 41 static int _UTF8_mbsinit(const mbstate_t *); 42 static size_t _UTF8_mbsnrtowcs(wchar_t *_RESTRICT_KYWD, 43 const char **_RESTRICT_KYWD, size_t, size_t, 44 mbstate_t *_RESTRICT_KYWD); 45 static size_t _UTF8_wcrtomb(char *_RESTRICT_KYWD, wchar_t, 46 mbstate_t *_RESTRICT_KYWD); 47 static size_t _UTF8_wcsnrtombs(char *_RESTRICT_KYWD, 48 const wchar_t **_RESTRICT_KYWD, 49 size_t, size_t, mbstate_t *_RESTRICT_KYWD); 50 51 typedef struct { 52 wchar_t ch; 53 int want; 54 wchar_t lbound; 55 } _UTF8State; 56 57 void 58 _UTF8_init(struct lc_ctype *lct) 59 { 60 lct->lc_mbrtowc = _UTF8_mbrtowc; 61 lct->lc_wcrtomb = _UTF8_wcrtomb; 62 lct->lc_mbsinit = _UTF8_mbsinit; 63 lct->lc_mbsnrtowcs = _UTF8_mbsnrtowcs; 64 lct->lc_wcsnrtombs = _UTF8_wcsnrtombs; 65 lct->lc_is_ascii = 0; 66 lct->lc_max_mblen = 4; 67 } 68 69 static int 70 _UTF8_mbsinit(const mbstate_t *ps) 71 { 72 73 return (ps == NULL || ((const _UTF8State *)ps)->want == 0); 74 } 75 76 static size_t 77 _UTF8_mbrtowc(wchar_t *_RESTRICT_KYWD pwc, const char *_RESTRICT_KYWD s, 78 size_t n, mbstate_t *_RESTRICT_KYWD ps) 79 { 80 _UTF8State *us; 81 int ch, i, mask, want; 82 wchar_t lbound, wch; 83 84 us = (_UTF8State *)ps; 85 86 if (us->want < 0 || us->want > 6) { 87 errno = EINVAL; 88 return ((size_t)-1); 89 } 90 91 if (s == NULL) { 92 s = ""; 93 n = 1; 94 pwc = NULL; 95 } 96 97 if (n == 0) 98 /* Incomplete multibyte sequence */ 99 return ((size_t)-2); 100 101 if (us->want == 0) { 102 /* 103 * Determine the number of octets that make up this character 104 * from the first octet, and a mask that extracts the 105 * interesting bits of the first octet. We already know 106 * the character is at least two bytes long. 107 * 108 * We also specify a lower bound for the character code to 109 * detect redundant, non-"shortest form" encodings. For 110 * example, the sequence C0 80 is _not_ a legal representation 111 * of the null character. This enforces a 1-to-1 mapping 112 * between character codes and their multibyte representations. 113 */ 114 ch = (unsigned char)*s; 115 if ((ch & 0x80) == 0) { 116 /* Fast path for plain ASCII characters. */ 117 if (pwc != NULL) 118 *pwc = ch; 119 return (ch != '\0' ? 1 : 0); 120 } 121 if ((ch & 0xe0) == 0xc0) { 122 mask = 0x1f; 123 want = 2; 124 lbound = 0x80; 125 } else if ((ch & 0xf0) == 0xe0) { 126 mask = 0x0f; 127 want = 3; 128 lbound = 0x800; 129 } else if ((ch & 0xf8) == 0xf0) { 130 mask = 0x07; 131 want = 4; 132 lbound = 0x10000; 133 #if 0 134 /* These would be illegal in the UTF-8 space */ 135 136 } else if ((ch & 0xfc) == 0xf8) { 137 mask = 0x03; 138 want = 5; 139 lbound = 0x200000; 140 } else if ((ch & 0xfe) == 0xfc) { 141 mask = 0x01; 142 want = 6; 143 lbound = 0x4000000; 144 #endif 145 } else { 146 /* 147 * Malformed input; input is not UTF-8. 148 */ 149 errno = EILSEQ; 150 return ((size_t)-1); 151 } 152 } else { 153 want = us->want; 154 lbound = us->lbound; 155 } 156 157 /* 158 * Decode the octet sequence representing the character in chunks 159 * of 6 bits, most significant first. 160 */ 161 if (us->want == 0) 162 wch = (unsigned char)*s++ & mask; 163 else 164 wch = us->ch; 165 166 for (i = (us->want == 0) ? 1 : 0; i < MIN(want, n); i++) { 167 if ((*s & 0xc0) != 0x80) { 168 /* 169 * Malformed input; bad characters in the middle 170 * of a character. 171 */ 172 errno = EILSEQ; 173 return ((size_t)-1); 174 } 175 wch <<= 6; 176 wch |= *s++ & 0x3f; 177 } 178 if (i < want) { 179 /* Incomplete multibyte sequence. */ 180 us->want = want - i; 181 us->lbound = lbound; 182 us->ch = wch; 183 return ((size_t)-2); 184 } 185 if (wch < lbound) { 186 /* 187 * Malformed input; redundant encoding. 188 */ 189 errno = EILSEQ; 190 return ((size_t)-1); 191 } 192 if (pwc != NULL) 193 *pwc = wch; 194 us->want = 0; 195 return (wch == L'\0' ? 0 : want); 196 } 197 198 static size_t 199 _UTF8_mbsnrtowcs(wchar_t *_RESTRICT_KYWD dst, const char **_RESTRICT_KYWD src, 200 size_t nms, size_t len, mbstate_t *_RESTRICT_KYWD ps) 201 { 202 _UTF8State *us; 203 const char *s; 204 size_t nchr; 205 wchar_t wc; 206 size_t nb; 207 208 us = (_UTF8State *)ps; 209 210 s = *src; 211 nchr = 0; 212 213 if (dst == NULL) { 214 /* 215 * The fast path in the loop below is not safe if an ASCII 216 * character appears as anything but the first byte of a 217 * multibyte sequence. Check now to avoid doing it in the loop. 218 */ 219 if (nms > 0 && us->want > 0 && (signed char)*s > 0) { 220 errno = EILSEQ; 221 return ((size_t)-1); 222 } 223 for (;;) { 224 if (nms > 0 && (signed char)*s > 0) 225 /* 226 * Fast path for plain ASCII characters 227 * excluding NUL. 228 */ 229 nb = 1; 230 else if ((nb = _UTF8_mbrtowc(&wc, s, nms, ps)) == 231 (size_t)-1) 232 /* Invalid sequence - mbrtowc() sets errno. */ 233 return ((size_t)-1); 234 else if (nb == 0 || nb == (size_t)-2) 235 return (nchr); 236 s += nb; 237 nms -= nb; 238 nchr++; 239 } 240 /*NOTREACHED*/ 241 } 242 243 /* 244 * The fast path in the loop below is not safe if an ASCII 245 * character appears as anything but the first byte of a 246 * multibyte sequence. Check now to avoid doing it in the loop. 247 */ 248 if (nms > 0 && len > 0 && us->want > 0 && (signed char)*s > 0) { 249 errno = EILSEQ; 250 return ((size_t)-1); 251 } 252 while (len-- > 0) { 253 if (nms > 0 && (signed char)*s > 0) { 254 /* 255 * Fast path for plain ASCII characters 256 * excluding NUL. 257 */ 258 *dst = (wchar_t)*s; 259 nb = 1; 260 } else if ((nb = _UTF8_mbrtowc(dst, s, nms, ps)) == 261 (size_t)-1) { 262 *src = s; 263 return ((size_t)-1); 264 } else if (nb == (size_t)-2) { 265 *src = s + nms; 266 return (nchr); 267 } else if (nb == 0) { 268 *src = NULL; 269 return (nchr); 270 } 271 s += nb; 272 nms -= nb; 273 nchr++; 274 dst++; 275 } 276 *src = s; 277 return (nchr); 278 } 279 280 static size_t 281 _UTF8_wcrtomb(char *_RESTRICT_KYWD s, wchar_t wc, mbstate_t *_RESTRICT_KYWD ps) 282 { 283 _UTF8State *us; 284 unsigned char lead; 285 int i, len; 286 287 us = (_UTF8State *)ps; 288 289 if (us->want != 0) { 290 errno = EINVAL; 291 return ((size_t)-1); 292 } 293 294 if (s == NULL) 295 /* Reset to initial shift state (no-op) */ 296 return (1); 297 298 /* 299 * Determine the number of octets needed to represent this character. 300 * We always output the shortest sequence possible. Also specify the 301 * first few bits of the first octet, which contains the information 302 * about the sequence length. 303 */ 304 if ((wc & ~0x7f) == 0) { 305 /* Fast path for plain ASCII characters. */ 306 *s = (char)wc; 307 return (1); 308 } else if ((wc & ~0x7ff) == 0) { 309 lead = 0xc0; 310 len = 2; 311 } else if ((wc & ~0xffff) == 0) { 312 lead = 0xe0; 313 len = 3; 314 } else if ((wc & ~0x1fffff) == 0) { 315 lead = 0xf0; 316 len = 4; 317 #if 0 318 /* Again, 5 and 6 byte encodings are simply not permitted */ 319 } else if ((wc & ~0x3ffffff) == 0) { 320 lead = 0xf8; 321 len = 5; 322 } else if ((wc & ~0x7fffffff) == 0) { 323 lead = 0xfc; 324 len = 6; 325 #endif 326 } else { 327 errno = EILSEQ; 328 return ((size_t)-1); 329 } 330 331 /* 332 * Output the octets representing the character in chunks 333 * of 6 bits, least significant last. The first octet is 334 * a special case because it contains the sequence length 335 * information. 336 */ 337 for (i = len - 1; i > 0; i--) { 338 s[i] = (wc & 0x3f) | 0x80; 339 wc >>= 6; 340 } 341 *s = (wc & 0xff) | lead; 342 343 return (len); 344 } 345 346 static size_t 347 _UTF8_wcsnrtombs(char *_RESTRICT_KYWD dst, const wchar_t **_RESTRICT_KYWD src, 348 size_t nwc, size_t len, mbstate_t *_RESTRICT_KYWD ps) 349 { 350 _UTF8State *us; 351 char buf[MB_LEN_MAX]; 352 const wchar_t *s; 353 size_t nbytes; 354 size_t nb; 355 356 us = (_UTF8State *)ps; 357 358 if (us->want != 0) { 359 errno = EINVAL; 360 return ((size_t)-1); 361 } 362 363 s = *src; 364 nbytes = 0; 365 366 if (dst == NULL) { 367 while (nwc-- > 0) { 368 if (0 <= *s && *s < 0x80) 369 /* Fast path for plain ASCII characters. */ 370 nb = 1; 371 else if ((nb = _UTF8_wcrtomb(buf, *s, ps)) == 372 (size_t)-1) 373 /* Invalid character - wcrtomb() sets errno. */ 374 return ((size_t)-1); 375 if (*s == L'\0') 376 return (nbytes + nb - 1); 377 s++; 378 nbytes += nb; 379 } 380 return (nbytes); 381 } 382 383 while (len > 0 && nwc-- > 0) { 384 if (0 <= *s && *s < 0x80) { 385 /* Fast path for plain ASCII characters. */ 386 nb = 1; 387 *dst = *s; 388 } else if (len > (size_t)MB_CUR_MAX) { 389 /* Enough space to translate in-place. */ 390 if ((nb = _UTF8_wcrtomb(dst, *s, ps)) == (size_t)-1) { 391 *src = s; 392 return ((size_t)-1); 393 } 394 } else { 395 /* 396 * May not be enough space; use temp. buffer. 397 */ 398 if ((nb = _UTF8_wcrtomb(buf, *s, ps)) == (size_t)-1) { 399 *src = s; 400 return ((size_t)-1); 401 } 402 if (nb > (int)len) 403 /* MB sequence for character won't fit. */ 404 break; 405 (void) memcpy(dst, buf, nb); 406 } 407 if (*s == L'\0') { 408 *src = NULL; 409 return (nbytes + nb - 1); 410 } 411 s++; 412 dst += nb; 413 len -= nb; 414 nbytes += nb; 415 } 416 *src = s; 417 return (nbytes); 418 } 419