blob: 5dd1a7d1b6c958d945d40594a6038a08e66948e1 [file] [log] [blame]
/*
* Copyright (C) 2001, International Business Machines Corporation and others. All Rights Reserved.
**********************************************************************
* Date Name Description
* 07/18/01 aliu Creation.
**********************************************************************
*/
#include "unicode/unifilt.h"
#include "unicode/rep.h"
#include "rbt_rule.h"
U_NAMESPACE_BEGIN
/**
* Default implementation of UnicodeMatcher::matches() for Unicode
* filters. Matches a single code point at offset (either one or
* two 16-bit code units).
*/
UMatchDegree UnicodeFilter::matches(const Replaceable& text,
int32_t& offset,
int32_t limit,
UBool incremental) {
UChar32 c;
if (offset < limit &&
contains(c = text.char32At(offset))) {
offset += UTF_CHAR_LENGTH(c);
return U_MATCH;
}
if (offset > limit &&
contains(c = text.char32At(offset))) {
// Backup offset by 1, unless the preceding character is a
// surrogate pair -- then backup by 2 (keep offset pointing at
// the lead surrogate).
--offset;
if (offset >= 0) {
offset -= UTF_CHAR_LENGTH(text.char32At(offset)) - 1;
}
return U_MATCH;
}
if (incremental && offset == limit) {
return U_PARTIAL_MATCH;
}
return U_MISMATCH;
}
// Stub this out for filters that do not implement a pattern
UnicodeString& UnicodeFilter::toPattern(UnicodeString& result,
UBool escapeUnprintable) const {
return result;
}
// Stub this out for filters that do not implement indexing
UBool UnicodeFilter::matchesIndexValue(uint8_t v) const {
return FALSE;
}
U_NAMESPACE_END
//eof