diff options
Diffstat (limited to 'lib/mbrtowc-impl-utf8.h')
| -rw-r--r-- | lib/mbrtowc-impl-utf8.h | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/lib/mbrtowc-impl-utf8.h b/lib/mbrtowc-impl-utf8.h new file mode 100644 index 00000000..8e5ac14e --- /dev/null +++ b/lib/mbrtowc-impl-utf8.h @@ -0,0 +1,138 @@ +/* Convert multibyte character to wide character. + Copyright (C) 1999-2002, 2005-2022 Free Software Foundation, Inc. + + This file is free software: you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + This file 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 Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser 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 part of the body of the mbrtowc and mbrtoc32 functions + that handles the special case of the UTF-8 encoding. */ + + /* 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) + { + unsigned int wc = + (((unsigned int) (c & 0x0f) << 12) + | ((unsigned int) (c2 ^ 0x80) << 6) + | (unsigned int) (c3 ^ 0x80)); + + if (FITS_IN_CHAR_TYPE (wc)) + { + if (pwc != NULL) + *pwc = wc; + 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) + { + unsigned int wc = + (((unsigned int) (c & 0x07) << 18) + | ((unsigned int) (c2 ^ 0x80) << 12) + | ((unsigned int) (c3 ^ 0x80) << 6) + | (unsigned int) (c4 ^ 0x80)); + + if (FITS_IN_CHAR_TYPE (wc)) + { + if (pwc != NULL) + *pwc = wc; + res = 4; + goto success; + } + } + } + } + } + } + } + } + } + goto invalid; |