1 // 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ********************************************************************** 5 * Copyright (c) 2001-2012, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ********************************************************************** 8 * Date Name Description 9 * 07/18/01 aliu Creation. 10 ********************************************************************** 11 */ 12 13 #include "unicode/unifilt.h" 14 #include "unicode/rep.h" 15 #include "unicode/utf16.h" 16 17 U_NAMESPACE_BEGIN 18 UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(UnicodeFilter) 19 20 21 /* Define this here due to the lack of another file. 22 It can't be defined in the header */ 23 UnicodeMatcher::~UnicodeMatcher() {} 24 25 UnicodeFilter::~UnicodeFilter() {} 26 27 /** 28 * UnicodeFunctor API. 29 * Note that UnicodeMatcher is a base class of UnicodeFilter. 30 */ 31 UnicodeMatcher* UnicodeFilter::toMatcher() const { 32 return const_cast<UnicodeFilter *>(this); 33 } 34 35 void UnicodeFilter::setData(const TransliterationRuleData*) {} 36 37 /** 38 * Default implementation of UnicodeMatcher::matches() for Unicode 39 * filters. Matches a single code point at offset (either one or 40 * two 16-bit code units). 41 */ 42 UMatchDegree UnicodeFilter::matches(const Replaceable& text, 43 int32_t& offset, 44 int32_t limit, 45 UBool incremental) { 46 UChar32 c; 47 if (offset < limit && 48 contains(c = text.char32At(offset))) { 49 offset += U16_LENGTH(c); 50 return U_MATCH; 51 } 52 if (offset > limit && 53 contains(c = text.char32At(offset))) { 54 // Backup offset by 1, unless the preceding character is a 55 // surrogate pair -- then backup by 2 (keep offset pointing at 56 // the lead surrogate). 57 --offset; 58 if (offset >= 0) { 59 offset -= U16_LENGTH(text.char32At(offset)) - 1; 60 } 61 return U_MATCH; 62 } 63 if (incremental && offset == limit) { 64 return U_PARTIAL_MATCH; 65 } 66 return U_MISMATCH; 67 } 68 69 U_NAMESPACE_END 70 71 //eof 72
