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Diffstat (limited to 'lib/uniwbrk/u-wordbreaks.h')
| -rw-r--r-- | lib/uniwbrk/u-wordbreaks.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/lib/uniwbrk/u-wordbreaks.h b/lib/uniwbrk/u-wordbreaks.h new file mode 100644 index 00000000..5ef4e8c1 --- /dev/null +++ b/lib/uniwbrk/u-wordbreaks.h @@ -0,0 +1,127 @@ +/* Word breaks in UTF-8/UTF-16/UTF-32 strings. + Copyright (C) 2009 Free Software Foundation, Inc. + Written by Bruno Haible <bruno@clisp.org>, 2009. + + This program 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 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 + 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 <http://www.gnu.org/licenses/>. */ + +void +FUNC (const UNIT *s, size_t n, char *p) +{ + if (n > 0) + { + const UNIT *s_end = s + n; + + /* Word break property of the last character. + -1 at the very beginning of the string. */ + int last_char_prop = -1; + + /* Format and Extend characters are ignored; this means, the mostly used + unit is the complex character (= character with subsequent ignored + characters). + Word break property of the last complex character. + -1 at the very beginning of the string. */ + int last_compchar_prop = -1; + char *last_compchar_ptr = NULL; + + /* For recognizing rules involving 3 complex characters: + Word break property of the second-to-last complex character. + -1 at the very beginning of the string. */ + int secondlast_compchar_prop = -1; + + /* Don't break inside multibyte characters. */ + memset (p, 0, n); + + while (s < s_end) + { + ucs4_t uc; + int count = U_MBTOUC_UNSAFE (&uc, s, s_end - s); + int prop = uc_wordbreak_property (uc); + + /* No break at the start of the string. */ + if (last_char_prop >= 0) + { + /* No break between CR and LF. */ + if (last_char_prop == WBP_CR && prop == WBP_LF) + /* *p = 0 */; + /* Break before and after newlines. */ + else if (last_char_prop >= WBP_NEWLINE + /* same as: + last_char_prop == WBP_CR + || last_char_prop == WBP_LF + || last_char_prop == WBP_NEWLINE */ + || prop >= WBP_NEWLINE + /* same as: + prop == WBP_CR + || prop == WBP_LF + || prop == WBP_NEWLINE */) + *p = 1; + /* Ignore Format and Extend characters. */ + else if (!(prop == WBP_EXTEND || prop == WBP_FORMAT)) + { + /* No break in these situations (see UAX #29): + + secondlast last current + + ALetter (MidLetter | MidNumLet) × ALetter (WB7) + ALetter × (MidLetter | MidNumLet) ALetter (WB6) + Numeric (MidNum | MidNumLet) × Numeric (WB11) + Numeric × (MidNum | MidNumLet) Numeric (WB12) + ALetter × ALetter (WB5) + ALetter × Numeric (WB9) + Numeric × ALetter (WB10) + Numeric × Numeric (WB8) + Katakana × Katakana (WB13) + (ALetter | Numeric | Katakana) × ExtendNumLet (WB13a) + ExtendNumLet × ExtendNumLet (WB13a) + ExtendNumLet × (ALetter | Numeric | Katakana) (WB13b) + */ + /* No break across certain punctuation. Also, disable word + breaks that were recognized earlier (due to lookahead of + only one complex character). */ + if ((prop == WBP_ALETTER + && (last_compchar_prop == WBP_MIDLETTER + || last_compchar_prop == WBP_MIDNUMLET) + && secondlast_compchar_prop == WBP_ALETTER) + || (prop == WBP_NUMERIC + && (last_compchar_prop == WBP_MIDNUM + || last_compchar_prop == WBP_MIDNUMLET) + && secondlast_compchar_prop == WBP_NUMERIC)) + { + *last_compchar_ptr = 0; + /* *p = 0; */ + } + else + { + /* Perform a single table lookup. */ + if (uniwbrk_table[last_compchar_prop][prop]) + *p = 1; + /* else *p = 0; */ + } + } + } + + last_char_prop = prop; + /* Ignore Format and Extend characters, except at the start of the string. */ + if (last_compchar_prop < 0 || !(prop == WBP_EXTEND || prop == WBP_FORMAT)) + { + secondlast_compchar_prop = last_compchar_prop; + last_compchar_prop = prop; + last_compchar_ptr = p; + } + + s += count; + p += count; + } + } +} |