| /* Convert multibyte character to wide character. |
| Copyright (C) 1999-2002, 2005-2019 Free Software Foundation, Inc. |
| Written by Bruno Haible <bruno@clisp.org>, 2008. |
| |
| 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/>. */ |
| |
| #include <config.h> |
| |
| /* Specification. */ |
| #include <wchar.h> |
| |
| #if C_LOCALE_MAYBE_EILSEQ |
| # include "hard-locale.h" |
| # include <locale.h> |
| #endif |
| |
| #if GNULIB_defined_mbstate_t |
| /* Implement mbrtowc() on top of mbtowc(). */ |
| |
| # include <errno.h> |
| # include <stdlib.h> |
| |
| # include "localcharset.h" |
| # include "streq.h" |
| # include "verify.h" |
| # include "glthread/lock.h" |
| |
| # ifndef FALLTHROUGH |
| # if __GNUC__ < 7 |
| # define FALLTHROUGH ((void) 0) |
| # else |
| # define FALLTHROUGH __attribute__ ((__fallthrough__)) |
| # endif |
| # endif |
| |
| /* Returns a classification of special values of the encoding of the current |
| locale. */ |
| typedef enum { |
| enc_other, /* other */ |
| enc_utf8, /* UTF-8 */ |
| enc_eucjp, /* EUC-JP */ |
| enc_94, /* EUC-KR, GB2312, BIG5 */ |
| enc_euctw, /* EUC-TW */ |
| enc_gb18030, /* GB18030 */ |
| enc_sjis /* SJIS */ |
| } enc_t; |
| static inline enc_t |
| locale_enc (void) |
| { |
| const char *encoding = locale_charset (); |
| if (STREQ_OPT (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0, 0)) |
| return enc_utf8; |
| if (STREQ_OPT (encoding, "EUC-JP", 'E', 'U', 'C', '-', 'J', 'P', 0, 0, 0)) |
| return enc_eucjp; |
| if (STREQ_OPT (encoding, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0) |
| || STREQ_OPT (encoding, "GB2312", 'G', 'B', '2', '3', '1', '2', 0, 0, 0) |
| || STREQ_OPT (encoding, "BIG5", 'B', 'I', 'G', '5', 0, 0, 0, 0, 0)) |
| return enc_94; |
| if (STREQ_OPT (encoding, "EUC-TW", 'E', 'U', 'C', '-', 'T', 'W', 0, 0, 0)) |
| return enc_euctw; |
| if (STREQ_OPT (encoding, "GB18030", 'G', 'B', '1', '8', '0', '3', '0', 0, 0)) |
| return enc_gb18030; |
| if (STREQ_OPT (encoding, "SJIS", 'S', 'J', 'I', 'S', 0, 0, 0, 0, 0)) |
| return enc_sjis; |
| return enc_other; |
| } |
| |
| # if GNULIB_WCHAR_SINGLE |
| /* When we know that the locale does not change, provide a speedup by |
| caching the value of locale_enc. */ |
| static int cached_locale_enc = -1; |
| static inline enc_t |
| locale_enc_cached (void) |
| { |
| if (cached_locale_enc < 0) |
| cached_locale_enc = locale_enc (); |
| return cached_locale_enc; |
| } |
| # else |
| /* By default, don't make assumptions, hence no caching. */ |
| # define locale_enc_cached locale_enc |
| # endif |
| |
| /* This lock protects the internal state of mbtowc against multiple simultaneous |
| calls of mbrtowc. */ |
| gl_lock_define_initialized(static, mbtowc_lock) |
| |
| verify (sizeof (mbstate_t) >= 4); |
| |
| static char internal_state[4]; |
| |
| size_t |
| mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps) |
| { |
| 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_enc_cached (); |
| |
| if (enc == enc_utf8) /* UTF-8 */ |
| { |
| /* Achieve multi-thread safety by not calling mbtowc() at all. */ |
| /* Cf. unistr/u8-mbtouc.c. */ |
| unsigned char c = (unsigned char) p[0]; |
| |
| if (c < 0x80) |
| { |
| if (pwc != NULL) |
| *pwc = c; |
| res = (c == 0 ? 0 : 1); |
| goto success; |
| } |
| if (c >= 0xc2) |
| { |
| if (c < 0xe0) |
| { |
| if (m == 1) |
| goto incomplete; |
| else /* m >= 2 */ |
| { |
| unsigned char c2 = (unsigned char) p[1]; |
| |
| if ((c2 ^ 0x80) < 0x40) |
| { |
| if (pwc != NULL) |
| *pwc = ((unsigned int) (c & 0x1f) << 6) |
| | (unsigned int) (c2 ^ 0x80); |
| res = 2; |
| goto success; |
| } |
| } |
| } |
| else if (c < 0xf0) |
| { |
| if (m == 1) |
| goto incomplete; |
| else |
| { |
| unsigned char c2 = (unsigned char) p[1]; |
| |
| if ((c2 ^ 0x80) < 0x40 |
| && (c >= 0xe1 || c2 >= 0xa0) |
| && (c != 0xed || c2 < 0xa0)) |
| { |
| if (m == 2) |
| goto incomplete; |
| else /* m >= 3 */ |
| { |
| unsigned char c3 = (unsigned char) p[2]; |
| |
| if ((c3 ^ 0x80) < 0x40) |
| { |
| if (pwc != NULL) |
| *pwc = ((unsigned int) (c & 0x0f) << 12) |
| | ((unsigned int) (c2 ^ 0x80) << 6) |
| | (unsigned int) (c3 ^ 0x80); |
| res = 3; |
| goto success; |
| } |
| } |
| } |
| } |
| } |
| else if (c <= 0xf4) |
| { |
| if (m == 1) |
| goto incomplete; |
| else |
| { |
| unsigned char c2 = (unsigned char) p[1]; |
| |
| if ((c2 ^ 0x80) < 0x40 |
| && (c >= 0xf1 || c2 >= 0x90) |
| && (c < 0xf4 || (c == 0xf4 && c2 < 0x90))) |
| { |
| if (m == 2) |
| goto incomplete; |
| else |
| { |
| unsigned char c3 = (unsigned char) p[2]; |
| |
| if ((c3 ^ 0x80) < 0x40) |
| { |
| if (m == 3) |
| goto incomplete; |
| else /* m >= 4 */ |
| { |
| unsigned char c4 = (unsigned char) p[3]; |
| |
| if ((c4 ^ 0x80) < 0x40) |
| { |
| if (pwc != NULL) |
| *pwc = ((unsigned int) (c & 0x07) << 18) |
| | ((unsigned int) (c2 ^ 0x80) << 12) |
| | ((unsigned int) (c3 ^ 0x80) << 6) |
| | (unsigned int) (c4 ^ 0x80); |
| res = 4; |
| goto success; |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| goto invalid; |
| } |
| else |
| { |
| /* The hidden internal state of mbtowc would make this function not |
| multi-thread safe. Achieve multi-thread safety through a lock. */ |
| gl_lock_lock (mbtowc_lock); |
| |
| /* Put the hidden internal state of mbtowc into its initial state. |
| This is needed at least with glibc, uClibc, and MSVC CRT. |
| See <https://sourceware.org/bugzilla/show_bug.cgi?id=9674>. */ |
| mbtowc (NULL, NULL, 0); |
| |
| res = mbtowc (pwc, p, m); |
| |
| gl_lock_unlock (mbtowc_lock); |
| |
| if (res >= 0) |
| { |
| if (pwc != NULL && ((*pwc == 0) != (res == 0))) |
| abort (); |
| 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 (pwc, 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); |
| } |
| } |
| |
| #else |
| /* Override the system's mbrtowc() function. */ |
| |
| # undef mbrtowc |
| |
| size_t |
| rpl_mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps) |
| { |
| size_t ret; |
| wchar_t wc; |
| |
| # if MBRTOWC_NULL_ARG2_BUG || MBRTOWC_RETVAL_BUG || MBRTOWC_EMPTY_INPUT_BUG |
| if (s == NULL) |
| { |
| pwc = NULL; |
| s = ""; |
| n = 1; |
| } |
| # endif |
| |
| # if MBRTOWC_EMPTY_INPUT_BUG |
| if (n == 0) |
| return (size_t) -2; |
| # endif |
| |
| if (! pwc) |
| pwc = &wc; |
| |
| # if MBRTOWC_RETVAL_BUG |
| { |
| static mbstate_t internal_state; |
| |
| /* Override mbrtowc's internal state. We cannot call mbsinit() on the |
| hidden internal state, but we can call it on our variable. */ |
| if (ps == NULL) |
| ps = &internal_state; |
| |
| if (!mbsinit (ps)) |
| { |
| /* Parse the rest of the multibyte character byte for byte. */ |
| size_t count = 0; |
| for (; n > 0; s++, n--) |
| { |
| ret = mbrtowc (&wc, s, 1, ps); |
| |
| if (ret == (size_t)(-1)) |
| return (size_t)(-1); |
| count++; |
| if (ret != (size_t)(-2)) |
| { |
| /* The multibyte character has been completed. */ |
| *pwc = wc; |
| return (wc == 0 ? 0 : count); |
| } |
| } |
| return (size_t)(-2); |
| } |
| } |
| # endif |
| |
| ret = mbrtowc (pwc, s, n, ps); |
| |
| # if MBRTOWC_NUL_RETVAL_BUG |
| if (ret < (size_t) -2 && !*pwc) |
| return 0; |
| # endif |
| |
| # if C_LOCALE_MAYBE_EILSEQ |
| if ((size_t) -2 <= ret && n != 0 && ! hard_locale (LC_CTYPE)) |
| { |
| unsigned char uc = *s; |
| *pwc = uc; |
| return 1; |
| } |
| # endif |
| |
| return ret; |
| } |
| |
| #endif |
