// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 2012-2016, International Business Machines
* Corporation and others. All Rights Reserved.
*******************************************************************************
* utf8collationiterator.h
*
* created on: 2012nov12 (from utf16collationiterator.h & uitercollationiterator.h)
* created by: Markus W. Scherer
*/
#ifndef __UTF8COLLATIONITERATOR_H__
#define __UTF8COLLATIONITERATOR_H__
#include "unicode/utypes.h"
#if !UCONFIG_NO_COLLATION
#include "cmemory.h"
#include "collation.h"
#include "collationdata.h"
#include "collationiterator.h"
#include "normalizer2impl.h"
U_NAMESPACE_BEGIN
/**
* UTF-8 collation element and character iterator.
* Handles normalized UTF-8 text inline, with length or NUL-terminated.
* Unnormalized text is handled by a subclass.
*/
class U_I18N_API UTF8CollationIterator :
public CollationIterator {
public:
UTF8CollationIterator(
const CollationData *d, UBool numeric,
const uint8_t *s, int32_t p, int32_t len)
: CollationIterator(d, numeric),
u8(s), pos(p), length(len) {}
virtual ~UTF8CollationIterator();
virtual void resetToOffset(int32_t newOffset) override;
virtual int32_t getOffset()
const override;
virtual UChar32 nextCodePoint(UErrorCode &errorCode) override;
virtual UChar32 previousCodePoint(UErrorCode &errorCode) override;
protected:
/**
* For byte sequences that are illegal in UTF-8, an error value may be returned
* together with a bogus code point. The caller will ignore that code point.
*
* Special values may be returned for surrogate code points, which are also illegal in UTF-8,
* but the caller will treat them like U+FFFD because forbidSurrogateCodePoints() returns true.
*
* Valid lead surrogates are returned from inside a normalized text segment,
* where handleGetTrailSurrogate() will return the matching trail surrogate.
*/
virtual uint32_t handleNextCE32(UChar32 &c, UErrorCode &errorCode) override;
virtual UBool foundNULTerminator() override;
virtual UBool forbidSurrogateCodePoints()
const override;
virtual void forwardNumCodePoints(int32_t num, UErrorCode &errorCode) override;
virtual void backwardNumCodePoints(int32_t num, UErrorCode &errorCode) override;
const uint8_t *u8;
int32_t pos;
int32_t length;
// <0 for NUL-terminated strings
};
/**
* Incrementally checks the input text for FCD and normalizes where necessary.
*/
class U_I18N_API FCDUTF8CollationIterator :
public UTF8CollationIterator {
public:
FCDUTF8CollationIterator(
const CollationData *data, UBool numeric,
const uint8_t *s, int32_t p, int32_t len)
: UTF8CollationIterator(data, numeric, s, p, len),
state(CHECK_FWD), start(p),
nfcImpl(data->nfcImpl) {}
virtual ~FCDUTF8CollationIterator();
virtual void resetToOffset(int32_t newOffset) override;
virtual int32_t getOffset()
const override;
virtual UChar32 nextCodePoint(UErrorCode &errorCode) override;
virtual UChar32 previousCodePoint(UErrorCode &errorCode) override;
protected:
virtual uint32_t handleNextCE32(UChar32 &c, UErrorCode &errorCode) override;
virtual char16_t handleGetTrailSurrogate() override;
virtual UBool foundNULTerminator() override;
virtual void forwardNumCodePoints(int32_t num, UErrorCode &errorCode) override;
virtual void backwardNumCodePoints(int32_t num, UErrorCode &errorCode) override;
private:
UBool nextHasLccc()
const;
UBool previousHasTccc()
const;
/**
* Switches to forward checking if possible.
*/
void switchToForward();
/**
* Extends the FCD text segment forward or normalizes around pos.
* @return true if success
*/
UBool nextSegment(UErrorCode &errorCode);
/**
* Switches to backward checking.
*/
void switchToBackward();
/**
* Extends the FCD text segment backward or normalizes around pos.
* @return true if success
*/
UBool previousSegment(UErrorCode &errorCode);
UBool normalize(
const UnicodeString &s, UErrorCode &errorCode);
enum State {
/**
* The input text [start..pos[ passes the FCD check.
* Moving forward checks incrementally.
* limit is undefined.
*/
CHECK_FWD,
/**
* The input text [pos..limit[ passes the FCD check.
* Moving backward checks incrementally.
* start is undefined.
*/
CHECK_BWD,
/**
* The input text [start..limit[ passes the FCD check.
* pos tracks the current text index.
*/
IN_FCD_SEGMENT,
/**
* The input text [start..limit[ failed the FCD check and was normalized.
* pos tracks the current index in the normalized string.
*/
IN_NORMALIZED
};
State state;
int32_t start;
int32_t limit;
const Normalizer2Impl &nfcImpl;
UnicodeString normalized;
};
U_NAMESPACE_END
#endif // !UCONFIG_NO_COLLATION
#endif // __UTF8COLLATIONITERATOR_H__
