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-rw-r--r--intl/icu/source/common/unifilt.cpp71
1 files changed, 71 insertions, 0 deletions
diff --git a/intl/icu/source/common/unifilt.cpp b/intl/icu/source/common/unifilt.cpp
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+++ b/intl/icu/source/common/unifilt.cpp
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+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+**********************************************************************
+* Copyright (c) 2001-2012, 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 "unicode/utf16.h"
+
+U_NAMESPACE_BEGIN
+UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(UnicodeFilter)
+
+
+/* Define this here due to the lack of another file.
+ It can't be defined in the header */
+UnicodeMatcher::~UnicodeMatcher() {}
+
+UnicodeFilter::~UnicodeFilter() {}
+
+/**
+ * UnicodeFunctor API.
+ * Note that UnicodeMatcher is a base class of UnicodeFilter.
+ */
+UnicodeMatcher* UnicodeFilter::toMatcher() const {
+ return const_cast<UnicodeFilter *>(this);
+}
+
+void UnicodeFilter::setData(const TransliterationRuleData*) {}
+
+/**
+ * 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 += U16_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 -= U16_LENGTH(text.char32At(offset)) - 1;
+ }
+ return U_MATCH;
+ }
+ if (incremental && offset == limit) {
+ return U_PARTIAL_MATCH;
+ }
+ return U_MISMATCH;
+}
+
+U_NAMESPACE_END
+
+//eof