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author | Jörg Frings-Fürst <debian@jff.email> | 2018-07-08 23:15:22 +0200 |
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committer | Jörg Frings-Fürst <debian@jff.email> | 2018-07-08 23:15:22 +0200 |
commit | 853c9cf3718db7c9f6d723e45031016231e1cbd1 (patch) | |
tree | e6a5cafe819de3d14665da32bfd87259b089ec02 /lib/unicase/u-prefix-context.h | |
parent | 7b350538dddb27a4513158cb6b6405b85f175ad1 (diff) | |
parent | 10bd216b0099d2ae8cb22c664fb725165096f95c (diff) |
Merge branch 'release/debian/0.9.10-1'debian/0.9.10-1
Diffstat (limited to 'lib/unicase/u-prefix-context.h')
-rw-r--r-- | lib/unicase/u-prefix-context.h | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/lib/unicase/u-prefix-context.h b/lib/unicase/u-prefix-context.h new file mode 100644 index 0000000..b30ed6b --- /dev/null +++ b/lib/unicase/u-prefix-context.h @@ -0,0 +1,101 @@ +/* Case-mapping context of prefix UTF-8/UTF-16/UTF-32 string. + Copyright (C) 2009-2018 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 either: + + * 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. + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at your + option) any later version. + + or both in parallel, as here. + 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 <https://www.gnu.org/licenses/>. */ + +casing_prefix_context_t +FUNC1 (const UNIT *s, size_t n) +{ + return FUNC2 (s, n, unicase_empty_prefix_context); +} + +casing_prefix_context_t +FUNC2 (const UNIT *s, size_t n, casing_prefix_context_t a_context) +{ +#if 0 + /* Forward iteration. Slow for long strings. */ + casing_prefix_context_t context = a_context; + const UNIT *s_end = s + n; + + while (s < s_end) + { + ucs4_t uc; + int count = U_MBTOUC_UNSAFE (&uc, s, s_end - s); + + if (!uc_is_case_ignorable (uc)) + context.last_char_except_ignorable = uc; + + { + int ccc = uc_combining_class (uc); + if (ccc == UC_CCC_A || ccc == UC_CCC_NR) + context.last_char_normal_or_above = uc; + } + + s += count; + } + + return context; +#else + /* Iterate backwards, only as far as needed. */ + casing_prefix_context_t context; + ucs4_t last_char_except_ignorable = (ucs4_t)(-1); + ucs4_t last_char_normal_or_above = (ucs4_t)(-1); + const UNIT *p = s + n; + + for (;;) + { + ucs4_t uc; + p = U_PREV (&uc, p, s); + if (p == NULL) + break; + + if (last_char_except_ignorable == (ucs4_t)(-1)) + { + if (!uc_is_case_ignorable (uc)) + last_char_except_ignorable = uc; + } + + if (last_char_normal_or_above == (ucs4_t)(-1)) + { + int ccc = uc_combining_class (uc); + if (ccc == UC_CCC_A || ccc == UC_CCC_NR) + last_char_normal_or_above = uc; + } + + if (last_char_except_ignorable != (ucs4_t)(-1) + && last_char_normal_or_above != (ucs4_t)(-1)) + break; + } + context.last_char_except_ignorable = + (last_char_except_ignorable != (ucs4_t)(-1) + ? last_char_except_ignorable + : a_context.last_char_except_ignorable); + context.last_char_normal_or_above = + (last_char_normal_or_above != (ucs4_t)(-1) + ? last_char_normal_or_above + : a_context.last_char_normal_or_above); + + return context; +#endif +} |