| 1 | /* Convert multibyte character to wide character. |
| 2 | Copyright (C) 1999-2002, 2005-2009 Free Software Foundation, Inc. |
| 3 | Written by Bruno Haible <bruno@clisp.org>, 2008. |
| 4 | |
| 5 | This program is free software: you can redistribute it and/or modify |
| 6 | it under the terms of the GNU Lesser General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <config.h> |
| 19 | |
| 20 | /* Specification. */ |
| 21 | #include <wchar.h> |
| 22 | |
| 23 | #if GNULIB_defined_mbstate_t |
| 24 | /* Implement mbrtowc() on top of mbtowc(). */ |
| 25 | |
| 26 | # include <errno.h> |
| 27 | # include <stdlib.h> |
| 28 | |
| 29 | # include "localcharset.h" |
| 30 | # include "streq.h" |
| 31 | # include "verify.h" |
| 32 | |
| 33 | |
| 34 | verify (sizeof (mbstate_t) >= 4); |
| 35 | |
| 36 | static char internal_state[4]; |
| 37 | |
| 38 | size_t |
| 39 | mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps) |
| 40 | { |
| 41 | char *pstate = (char *)ps; |
| 42 | |
| 43 | if (pstate == NULL) |
| 44 | pstate = internal_state; |
| 45 | |
| 46 | if (s == NULL) |
| 47 | { |
| 48 | pwc = NULL; |
| 49 | s = ""; |
| 50 | n = 1; |
| 51 | } |
| 52 | |
| 53 | if (n == 0) |
| 54 | return (size_t)(-2); |
| 55 | |
| 56 | /* Here n > 0. */ |
| 57 | { |
| 58 | size_t nstate = pstate[0]; |
| 59 | char buf[4]; |
| 60 | const char *p; |
| 61 | size_t m; |
| 62 | |
| 63 | switch (nstate) |
| 64 | { |
| 65 | case 0: |
| 66 | p = s; |
| 67 | m = n; |
| 68 | break; |
| 69 | case 3: |
| 70 | buf[2] = pstate[3]; |
| 71 | /*FALLTHROUGH*/ |
| 72 | case 2: |
| 73 | buf[1] = pstate[2]; |
| 74 | /*FALLTHROUGH*/ |
| 75 | case 1: |
| 76 | buf[0] = pstate[1]; |
| 77 | p = buf; |
| 78 | m = nstate; |
| 79 | buf[m++] = s[0]; |
| 80 | if (n >= 2 && m < 4) |
| 81 | { |
| 82 | buf[m++] = s[1]; |
| 83 | if (n >= 3 && m < 4) |
| 84 | buf[m++] = s[2]; |
| 85 | } |
| 86 | break; |
| 87 | default: |
| 88 | errno = EINVAL; |
| 89 | return (size_t)(-1); |
| 90 | } |
| 91 | |
| 92 | /* Here m > 0. */ |
| 93 | |
| 94 | # if __GLIBC__ |
| 95 | /* Work around bug <http://sourceware.org/bugzilla/show_bug.cgi?id=9674> */ |
| 96 | mbtowc (NULL, NULL, 0); |
| 97 | # endif |
| 98 | { |
| 99 | int res = mbtowc (pwc, p, m); |
| 100 | |
| 101 | if (res >= 0) |
| 102 | { |
| 103 | if (pwc != NULL && ((*pwc == 0) != (res == 0))) |
| 104 | abort (); |
| 105 | if (nstate >= (res > 0 ? res : 1)) |
| 106 | abort (); |
| 107 | res -= nstate; |
| 108 | pstate[0] = 0; |
| 109 | return res; |
| 110 | } |
| 111 | |
| 112 | /* mbtowc does not distinguish between invalid and incomplete multibyte |
| 113 | sequences. But mbrtowc needs to make this distinction. |
| 114 | There are two possible approaches: |
| 115 | - Use iconv() and its return value. |
| 116 | - Use built-in knowledge about the possible encodings. |
| 117 | Given the low quality of implementation of iconv() on the systems that |
| 118 | lack mbrtowc(), we use the second approach. |
| 119 | The possible encodings are: |
| 120 | - 8-bit encodings, |
| 121 | - EUC-JP, EUC-KR, GB2312, EUC-TW, BIG5, GB18030, SJIS, |
| 122 | - UTF-8. |
| 123 | Use specialized code for each. */ |
| 124 | if (m >= 4 || m >= MB_CUR_MAX) |
| 125 | goto invalid; |
| 126 | /* Here MB_CUR_MAX > 1 and 0 < m < 4. */ |
| 127 | { |
| 128 | const char *encoding = locale_charset (); |
| 129 | |
| 130 | if (STREQ (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0, 0)) |
| 131 | { |
| 132 | /* Cf. unistr/u8-mblen.c. */ |
| 133 | unsigned char c = (unsigned char) p[0]; |
| 134 | |
| 135 | if (c >= 0xc2) |
| 136 | { |
| 137 | if (c < 0xe0) |
| 138 | { |
| 139 | if (m == 1) |
| 140 | goto incomplete; |
| 141 | } |
| 142 | else if (c < 0xf0) |
| 143 | { |
| 144 | if (m == 1) |
| 145 | goto incomplete; |
| 146 | if (m == 2) |
| 147 | { |
| 148 | unsigned char c2 = (unsigned char) p[1]; |
| 149 | |
| 150 | if ((c2 ^ 0x80) < 0x40 |
| 151 | && (c >= 0xe1 || c2 >= 0xa0) |
| 152 | && (c != 0xed || c2 < 0xa0)) |
| 153 | goto incomplete; |
| 154 | } |
| 155 | } |
| 156 | else if (c <= 0xf4) |
| 157 | { |
| 158 | if (m == 1) |
| 159 | goto incomplete; |
| 160 | else /* m == 2 || m == 3 */ |
| 161 | { |
| 162 | unsigned char c2 = (unsigned char) p[1]; |
| 163 | |
| 164 | if ((c2 ^ 0x80) < 0x40 |
| 165 | && (c >= 0xf1 || c2 >= 0x90) |
| 166 | && (c < 0xf4 || (c == 0xf4 && c2 < 0x90))) |
| 167 | { |
| 168 | if (m == 2) |
| 169 | goto incomplete; |
| 170 | else /* m == 3 */ |
| 171 | { |
| 172 | unsigned char c3 = (unsigned char) p[2]; |
| 173 | |
| 174 | if ((c3 ^ 0x80) < 0x40) |
| 175 | goto incomplete; |
| 176 | } |
| 177 | } |
| 178 | } |
| 179 | } |
| 180 | } |
| 181 | goto invalid; |
| 182 | } |
| 183 | |
| 184 | /* As a reference for this code, you can use the GNU libiconv |
| 185 | implementation. Look for uses of the RET_TOOFEW macro. */ |
| 186 | |
| 187 | if (STREQ (encoding, "EUC-JP", 'E', 'U', 'C', '-', 'J', 'P', 0, 0, 0)) |
| 188 | { |
| 189 | if (m == 1) |
| 190 | { |
| 191 | unsigned char c = (unsigned char) p[0]; |
| 192 | |
| 193 | if ((c >= 0xa1 && c < 0xff) || c == 0x8e || c == 0x8f) |
| 194 | goto incomplete; |
| 195 | } |
| 196 | if (m == 2) |
| 197 | { |
| 198 | unsigned char c = (unsigned char) p[0]; |
| 199 | |
| 200 | if (c == 0x8f) |
| 201 | { |
| 202 | unsigned char c2 = (unsigned char) p[1]; |
| 203 | |
| 204 | if (c2 >= 0xa1 && c2 < 0xff) |
| 205 | goto incomplete; |
| 206 | } |
| 207 | } |
| 208 | goto invalid; |
| 209 | } |
| 210 | if (STREQ (encoding, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0) |
| 211 | || STREQ (encoding, "GB2312", 'G', 'B', '2', '3', '1', '2', 0, 0, 0) |
| 212 | || STREQ (encoding, "BIG5", 'B', 'I', 'G', '5', 0, 0, 0, 0, 0)) |
| 213 | { |
| 214 | if (m == 1) |
| 215 | { |
| 216 | unsigned char c = (unsigned char) p[0]; |
| 217 | |
| 218 | if (c >= 0xa1 && c < 0xff) |
| 219 | goto incomplete; |
| 220 | } |
| 221 | goto invalid; |
| 222 | } |
| 223 | if (STREQ (encoding, "EUC-TW", 'E', 'U', 'C', '-', 'T', 'W', 0, 0, 0)) |
| 224 | { |
| 225 | if (m == 1) |
| 226 | { |
| 227 | unsigned char c = (unsigned char) p[0]; |
| 228 | |
| 229 | if ((c >= 0xa1 && c < 0xff) || c == 0x8e) |
| 230 | goto incomplete; |
| 231 | } |
| 232 | else /* m == 2 || m == 3 */ |
| 233 | { |
| 234 | unsigned char c = (unsigned char) p[0]; |
| 235 | |
| 236 | if (c == 0x8e) |
| 237 | goto incomplete; |
| 238 | } |
| 239 | goto invalid; |
| 240 | } |
| 241 | if (STREQ (encoding, "GB18030", 'G', 'B', '1', '8', '0', '3', '0', 0, 0)) |
| 242 | { |
| 243 | if (m == 1) |
| 244 | { |
| 245 | unsigned char c = (unsigned char) p[0]; |
| 246 | |
| 247 | if ((c >= 0x90 && c <= 0xe3) || (c >= 0xf8 && c <= 0xfe)) |
| 248 | goto incomplete; |
| 249 | } |
| 250 | else /* m == 2 || m == 3 */ |
| 251 | { |
| 252 | unsigned char c = (unsigned char) p[0]; |
| 253 | |
| 254 | if (c >= 0x90 && c <= 0xe3) |
| 255 | { |
| 256 | unsigned char c2 = (unsigned char) p[1]; |
| 257 | |
| 258 | if (c2 >= 0x30 && c2 <= 0x39) |
| 259 | { |
| 260 | if (m == 2) |
| 261 | goto incomplete; |
| 262 | else /* m == 3 */ |
| 263 | { |
| 264 | unsigned char c3 = (unsigned char) p[2]; |
| 265 | |
| 266 | if (c3 >= 0x81 && c3 <= 0xfe) |
| 267 | goto incomplete; |
| 268 | } |
| 269 | } |
| 270 | } |
| 271 | } |
| 272 | goto invalid; |
| 273 | } |
| 274 | if (STREQ (encoding, "SJIS", 'S', 'J', 'I', 'S', 0, 0, 0, 0, 0)) |
| 275 | { |
| 276 | if (m == 1) |
| 277 | { |
| 278 | unsigned char c = (unsigned char) p[0]; |
| 279 | |
| 280 | if ((c >= 0x81 && c <= 0x9f) || (c >= 0xe0 && c <= 0xea) |
| 281 | || (c >= 0xf0 && c <= 0xf9)) |
| 282 | goto incomplete; |
| 283 | } |
| 284 | goto invalid; |
| 285 | } |
| 286 | |
| 287 | /* An unknown multibyte encoding. */ |
| 288 | goto incomplete; |
| 289 | } |
| 290 | |
| 291 | incomplete: |
| 292 | { |
| 293 | size_t k = nstate; |
| 294 | /* Here 0 <= k < m < 4. */ |
| 295 | pstate[++k] = s[0]; |
| 296 | if (k < m) |
| 297 | { |
| 298 | pstate[++k] = s[1]; |
| 299 | if (k < m) |
| 300 | pstate[++k] = s[2]; |
| 301 | } |
| 302 | if (k != m) |
| 303 | abort (); |
| 304 | } |
| 305 | pstate[0] = m; |
| 306 | return (size_t)(-2); |
| 307 | |
| 308 | invalid: |
| 309 | errno = EILSEQ; |
| 310 | /* The conversion state is undefined, says POSIX. */ |
| 311 | return (size_t)(-1); |
| 312 | } |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | #else |
| 317 | /* Override the system's mbrtowc() function. */ |
| 318 | |
| 319 | # undef mbrtowc |
| 320 | |
| 321 | size_t |
| 322 | rpl_mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps) |
| 323 | { |
| 324 | # if MBRTOWC_NULL_ARG_BUG || MBRTOWC_RETVAL_BUG |
| 325 | if (s == NULL) |
| 326 | { |
| 327 | pwc = NULL; |
| 328 | s = ""; |
| 329 | n = 1; |
| 330 | } |
| 331 | # endif |
| 332 | |
| 333 | # if MBRTOWC_RETVAL_BUG |
| 334 | { |
| 335 | static mbstate_t internal_state; |
| 336 | |
| 337 | /* Override mbrtowc's internal state. We can not call mbsinit() on the |
| 338 | hidden internal state, but we can call it on our variable. */ |
| 339 | if (ps == NULL) |
| 340 | ps = &internal_state; |
| 341 | |
| 342 | if (!mbsinit (ps)) |
| 343 | { |
| 344 | /* Parse the rest of the multibyte character byte for byte. */ |
| 345 | size_t count = 0; |
| 346 | for (; n > 0; s++, n--) |
| 347 | { |
| 348 | wchar_t wc; |
| 349 | size_t ret = mbrtowc (&wc, s, 1, ps); |
| 350 | |
| 351 | if (ret == (size_t)(-1)) |
| 352 | return (size_t)(-1); |
| 353 | count++; |
| 354 | if (ret != (size_t)(-2)) |
| 355 | { |
| 356 | /* The multibyte character has been completed. */ |
| 357 | if (pwc != NULL) |
| 358 | *pwc = wc; |
| 359 | return (wc == 0 ? 0 : count); |
| 360 | } |
| 361 | } |
| 362 | return (size_t)(-2); |
| 363 | } |
| 364 | } |
| 365 | # endif |
| 366 | |
| 367 | # if MBRTOWC_NUL_RETVAL_BUG |
| 368 | { |
| 369 | wchar_t wc; |
| 370 | size_t ret = mbrtowc (&wc, s, n, ps); |
| 371 | |
| 372 | if (ret != (size_t)(-1) && ret != (size_t)(-2)) |
| 373 | { |
| 374 | if (pwc != NULL) |
| 375 | *pwc = wc; |
| 376 | if (wc == 0) |
| 377 | ret = 0; |
| 378 | } |
| 379 | return ret; |
| 380 | } |
| 381 | # else |
| 382 | return mbrtowc (pwc, s, n, ps); |
| 383 | # endif |
| 384 | } |
| 385 | |
| 386 | #endif |