diff options
Diffstat (limited to '')
-rw-r--r-- | intl/icu/source/i18n/titletrn.cpp | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/titletrn.cpp b/intl/icu/source/i18n/titletrn.cpp new file mode 100644 index 0000000000..d3732893a7 --- /dev/null +++ b/intl/icu/source/i18n/titletrn.cpp @@ -0,0 +1,170 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +********************************************************************** +* Copyright (C) 2001-2011, International Business Machines +* Corporation and others. All Rights Reserved. +********************************************************************** +* Date Name Description +* 05/24/01 aliu Creation. +********************************************************************** +*/ + +#include "unicode/utypes.h" + +#if !UCONFIG_NO_TRANSLITERATION + +#include "unicode/uchar.h" +#include "unicode/uniset.h" +#include "unicode/ustring.h" +#include "unicode/utf16.h" +#include "titletrn.h" +#include "umutex.h" +#include "ucase.h" +#include "cpputils.h" + +U_NAMESPACE_BEGIN + +UOBJECT_DEFINE_RTTI_IMPLEMENTATION(TitlecaseTransliterator) + +TitlecaseTransliterator::TitlecaseTransliterator() : + CaseMapTransliterator(UNICODE_STRING("Any-Title", 9), nullptr) +{ + // Need to look back 2 characters in the case of "can't" + setMaximumContextLength(2); +} + +/** + * Destructor. + */ +TitlecaseTransliterator::~TitlecaseTransliterator() { +} + +/** + * Copy constructor. + */ +TitlecaseTransliterator::TitlecaseTransliterator(const TitlecaseTransliterator& o) : + CaseMapTransliterator(o) +{ +} + +/** + * Assignment operator. + */ +/*TitlecaseTransliterator& TitlecaseTransliterator::operator=( + const TitlecaseTransliterator& o) { + CaseMapTransliterator::operator=(o); + return *this; +}*/ + +/** + * Transliterator API. + */ +TitlecaseTransliterator* TitlecaseTransliterator::clone() const { + return new TitlecaseTransliterator(*this); +} + +/** + * Implements {@link Transliterator#handleTransliterate}. + */ +void TitlecaseTransliterator::handleTransliterate( + Replaceable& text, UTransPosition& offsets, + UBool isIncremental) const +{ + // TODO reimplement, see ustrcase.c + // using a real word break iterator + // instead of just looking for a transition between cased and uncased characters + // call CaseMapTransliterator::handleTransliterate() for lowercasing? (set fMap) + // needs to take isIncremental into account because case mappings are context-sensitive + // also detect when lowercasing function did not finish because of context + + if (offsets.start >= offsets.limit) { + return; + } + + // case type: >0 cased (UCASE_LOWER etc.) ==0 uncased <0 case-ignorable + int32_t type; + + // Our mode; we are either converting letter toTitle or + // toLower. + UBool doTitle = true; + + // Determine if there is a preceding context of cased case-ignorable*, + // in which case we want to start in toLower mode. If the + // prior context is anything else (including empty) then start + // in toTitle mode. + UChar32 c; + int32_t start; + for (start = offsets.start - 1; start >= offsets.contextStart; start -= U16_LENGTH(c)) { + c = text.char32At(start); + type=ucase_getTypeOrIgnorable(c); + if(type>0) { // cased + doTitle=false; + break; + } else if(type==0) { // uncased but not ignorable + break; + } + // else (type<0) case-ignorable: continue + } + + // Convert things after a cased character toLower; things + // after an uncased, non-case-ignorable character toTitle. Case-ignorable + // characters are copied directly and do not change the mode. + UCaseContext csc; + uprv_memset(&csc, 0, sizeof(csc)); + csc.p = &text; + csc.start = offsets.contextStart; + csc.limit = offsets.contextLimit; + + UnicodeString tmp; + const char16_t *s; + int32_t textPos, delta, result; + + for(textPos=offsets.start; textPos<offsets.limit;) { + csc.cpStart=textPos; + c=text.char32At(textPos); + csc.cpLimit=textPos+=U16_LENGTH(c); + + type=ucase_getTypeOrIgnorable(c); + if(type>=0) { // not case-ignorable + if(doTitle) { + result=ucase_toFullTitle(c, utrans_rep_caseContextIterator, &csc, &s, UCASE_LOC_ROOT); + } else { + result=ucase_toFullLower(c, utrans_rep_caseContextIterator, &csc, &s, UCASE_LOC_ROOT); + } + doTitle = (UBool)(type==0); // doTitle=isUncased + + if(csc.b1 && isIncremental) { + // fMap() tried to look beyond the context limit + // wait for more input + offsets.start=csc.cpStart; + return; + } + + if(result>=0) { + // replace the current code point with its full case mapping result + // see UCASE_MAX_STRING_LENGTH + if(result<=UCASE_MAX_STRING_LENGTH) { + // string s[result] + tmp.setTo(false, s, result); + delta=result-U16_LENGTH(c); + } else { + // single code point + tmp.setTo(result); + delta=tmp.length()-U16_LENGTH(c); + } + text.handleReplaceBetween(csc.cpStart, textPos, tmp); + if(delta!=0) { + textPos+=delta; + csc.limit=offsets.contextLimit+=delta; + offsets.limit+=delta; + } + } + } + } + offsets.start=textPos; +} + +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_TRANSLITERATION */ |