| /* Convert multibyte character to wide character. |
| Copyright (C) 1999-2002, 2005-2021 Free Software Foundation, Inc. |
| |
| This program is free software: you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
| |
| /* Written by Bruno Haible <bruno@clisp.org>, 2008. */ |
| |
| /* This file contains the body of the mbrtowc and mbrtoc32 functions, |
| when GNULIB_defined_mbstate_t is defined. */ |
| |
| char *pstate = (char *)ps; |
| |
| if (s == NULL) |
| { |
| pwc = NULL; |
| s = ""; |
| n = 1; |
| } |
| |
| if (n == 0) |
| return (size_t)(-2); |
| |
| /* Here n > 0. */ |
| |
| if (pstate == NULL) |
| pstate = internal_state; |
| |
| { |
| size_t nstate = pstate[0]; |
| char buf[4]; |
| const char *p; |
| size_t m; |
| enc_t enc; |
| int res; |
| |
| switch (nstate) |
| { |
| case 0: |
| p = s; |
| m = n; |
| break; |
| case 3: |
| buf[2] = pstate[3]; |
| FALLTHROUGH; |
| case 2: |
| buf[1] = pstate[2]; |
| FALLTHROUGH; |
| case 1: |
| buf[0] = pstate[1]; |
| p = buf; |
| m = nstate; |
| buf[m++] = s[0]; |
| if (n >= 2 && m < 4) |
| { |
| buf[m++] = s[1]; |
| if (n >= 3 && m < 4) |
| buf[m++] = s[2]; |
| } |
| break; |
| default: |
| errno = EINVAL; |
| return (size_t)(-1); |
| } |
| |
| /* Here m > 0. */ |
| |
| enc = locale_encoding_classification (); |
| |
| if (enc == enc_utf8) /* UTF-8 */ |
| { |
| /* Achieve |
| - multi-thread safety and |
| - the ability to produce wide character values > WCHAR_MAX |
| by not calling mbtowc() at all. */ |
| #include "mbrtowc-impl-utf8.h" |
| } |
| else |
| { |
| /* The hidden internal state of mbtowc would make this function not |
| multi-thread safe. Achieve multi-thread safety through a lock. */ |
| wchar_t wc; |
| res = mbtowc_with_lock (&wc, p, m); |
| |
| if (res >= 0) |
| { |
| if ((wc == 0) != (res == 0)) |
| abort (); |
| if (pwc != NULL) |
| *pwc = wc; |
| goto success; |
| } |
| |
| /* mbtowc does not distinguish between invalid and incomplete multibyte |
| sequences. But mbrtowc needs to make this distinction. |
| There are two possible approaches: |
| - Use iconv() and its return value. |
| - Use built-in knowledge about the possible encodings. |
| Given the low quality of implementation of iconv() on the systems |
| that lack mbrtowc(), we use the second approach. |
| The possible encodings are: |
| - 8-bit encodings, |
| - EUC-JP, EUC-KR, GB2312, EUC-TW, BIG5, GB18030, SJIS, |
| - UTF-8 (already handled above). |
| Use specialized code for each. */ |
| if (m >= 4 || m >= MB_CUR_MAX) |
| goto invalid; |
| /* Here MB_CUR_MAX > 1 and 0 < m < 4. */ |
| switch (enc) |
| { |
| /* As a reference for this code, you can use the GNU libiconv |
| implementation. Look for uses of the RET_TOOFEW macro. */ |
| |
| case enc_eucjp: /* EUC-JP */ |
| { |
| if (m == 1) |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if ((c >= 0xa1 && c < 0xff) || c == 0x8e || c == 0x8f) |
| goto incomplete; |
| } |
| if (m == 2) |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if (c == 0x8f) |
| { |
| unsigned char c2 = (unsigned char) p[1]; |
| |
| if (c2 >= 0xa1 && c2 < 0xff) |
| goto incomplete; |
| } |
| } |
| goto invalid; |
| } |
| |
| case enc_94: /* EUC-KR, GB2312, BIG5 */ |
| { |
| if (m == 1) |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if (c >= 0xa1 && c < 0xff) |
| goto incomplete; |
| } |
| goto invalid; |
| } |
| |
| case enc_euctw: /* EUC-TW */ |
| { |
| if (m == 1) |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if ((c >= 0xa1 && c < 0xff) || c == 0x8e) |
| goto incomplete; |
| } |
| else /* m == 2 || m == 3 */ |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if (c == 0x8e) |
| goto incomplete; |
| } |
| goto invalid; |
| } |
| |
| case enc_gb18030: /* GB18030 */ |
| { |
| if (m == 1) |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if ((c >= 0x90 && c <= 0xe3) || (c >= 0xf8 && c <= 0xfe)) |
| goto incomplete; |
| } |
| else /* m == 2 || m == 3 */ |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if (c >= 0x90 && c <= 0xe3) |
| { |
| unsigned char c2 = (unsigned char) p[1]; |
| |
| if (c2 >= 0x30 && c2 <= 0x39) |
| { |
| if (m == 2) |
| goto incomplete; |
| else /* m == 3 */ |
| { |
| unsigned char c3 = (unsigned char) p[2]; |
| |
| if (c3 >= 0x81 && c3 <= 0xfe) |
| goto incomplete; |
| } |
| } |
| } |
| } |
| goto invalid; |
| } |
| |
| case enc_sjis: /* SJIS */ |
| { |
| if (m == 1) |
| { |
| unsigned char c = (unsigned char) p[0]; |
| |
| if ((c >= 0x81 && c <= 0x9f) || (c >= 0xe0 && c <= 0xea) |
| || (c >= 0xf0 && c <= 0xf9)) |
| goto incomplete; |
| } |
| goto invalid; |
| } |
| |
| default: |
| /* An unknown multibyte encoding. */ |
| goto incomplete; |
| } |
| } |
| |
| success: |
| /* res >= 0 is the corrected return value of |
| mbtowc_with_lock (&wc, p, m). */ |
| if (nstate >= (res > 0 ? res : 1)) |
| abort (); |
| res -= nstate; |
| pstate[0] = 0; |
| return res; |
| |
| incomplete: |
| { |
| size_t k = nstate; |
| /* Here 0 <= k < m < 4. */ |
| pstate[++k] = s[0]; |
| if (k < m) |
| { |
| pstate[++k] = s[1]; |
| if (k < m) |
| pstate[++k] = s[2]; |
| } |
| if (k != m) |
| abort (); |
| } |
| pstate[0] = m; |
| return (size_t)(-2); |
| |
| invalid: |
| errno = EILSEQ; |
| /* The conversion state is undefined, says POSIX. */ |
| return (size_t)(-1); |
| } |
