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diff --git a/Build/source/libs/icu/icu-4.8.1/common/normalizer2impl.h b/Build/source/libs/icu/icu-4.8.1/common/normalizer2impl.h new file mode 100644 index 00000000000..15b6d8c8b38 --- /dev/null +++ b/Build/source/libs/icu/icu-4.8.1/common/normalizer2impl.h @@ -0,0 +1,745 @@ +/* +******************************************************************************* +* +* Copyright (C) 2009-2011, International Business Machines +* Corporation and others. All Rights Reserved. +* +******************************************************************************* +* file name: normalizer2impl.h +* encoding: US-ASCII +* tab size: 8 (not used) +* indentation:4 +* +* created on: 2009nov22 +* created by: Markus W. Scherer +*/ + +#ifndef __NORMALIZER2IMPL_H__ +#define __NORMALIZER2IMPL_H__ + +#include "unicode/utypes.h" + +#if !UCONFIG_NO_NORMALIZATION + +#include "unicode/normalizer2.h" +#include "unicode/udata.h" +#include "unicode/unistr.h" +#include "unicode/unorm.h" +#include "mutex.h" +#include "uset_imp.h" +#include "utrie2.h" + +U_NAMESPACE_BEGIN + +struct CanonIterData; + +class Hangul { +public: + /* Korean Hangul and Jamo constants */ + enum { + JAMO_L_BASE=0x1100, /* "lead" jamo */ + JAMO_V_BASE=0x1161, /* "vowel" jamo */ + JAMO_T_BASE=0x11a7, /* "trail" jamo */ + + HANGUL_BASE=0xac00, + + JAMO_L_COUNT=19, + JAMO_V_COUNT=21, + JAMO_T_COUNT=28, + + JAMO_VT_COUNT=JAMO_V_COUNT*JAMO_T_COUNT, + + HANGUL_COUNT=JAMO_L_COUNT*JAMO_V_COUNT*JAMO_T_COUNT, + HANGUL_LIMIT=HANGUL_BASE+HANGUL_COUNT + }; + + static inline UBool isHangul(UChar32 c) { + return HANGUL_BASE<=c && c<HANGUL_LIMIT; + } + static inline UBool + isHangulWithoutJamoT(UChar c) { + c-=HANGUL_BASE; + return c<HANGUL_COUNT && c%JAMO_T_COUNT==0; + } + static inline UBool isJamoL(UChar32 c) { + return (uint32_t)(c-JAMO_L_BASE)<JAMO_L_COUNT; + } + static inline UBool isJamoV(UChar32 c) { + return (uint32_t)(c-JAMO_V_BASE)<JAMO_V_COUNT; + } + + /** + * Decomposes c, which must be a Hangul syllable, into buffer + * and returns the length of the decomposition (2 or 3). + */ + static inline int32_t decompose(UChar32 c, UChar buffer[3]) { + c-=HANGUL_BASE; + UChar32 c2=c%JAMO_T_COUNT; + c/=JAMO_T_COUNT; + buffer[0]=(UChar)(JAMO_L_BASE+c/JAMO_V_COUNT); + buffer[1]=(UChar)(JAMO_V_BASE+c%JAMO_V_COUNT); + if(c2==0) { + return 2; + } else { + buffer[2]=(UChar)(JAMO_T_BASE+c2); + return 3; + } + } +private: + Hangul(); // no instantiation +}; + +class Normalizer2Impl; + +class ReorderingBuffer : public UMemory { +public: + ReorderingBuffer(const Normalizer2Impl &ni, UnicodeString &dest) : + impl(ni), str(dest), + start(NULL), reorderStart(NULL), limit(NULL), + remainingCapacity(0), lastCC(0) {} + ~ReorderingBuffer() { + if(start!=NULL) { + str.releaseBuffer((int32_t)(limit-start)); + } + } + UBool init(int32_t destCapacity, UErrorCode &errorCode); + + UBool isEmpty() const { return start==limit; } + int32_t length() const { return (int32_t)(limit-start); } + UChar *getStart() { return start; } + UChar *getLimit() { return limit; } + uint8_t getLastCC() const { return lastCC; } + + UBool equals(const UChar *start, const UChar *limit) const; + + // For Hangul composition, replacing the Leading consonant Jamo with the syllable. + void setLastChar(UChar c) { + *(limit-1)=c; + } + + UBool append(UChar32 c, uint8_t cc, UErrorCode &errorCode) { + return (c<=0xffff) ? + appendBMP((UChar)c, cc, errorCode) : + appendSupplementary(c, cc, errorCode); + } + // s must be in NFD, otherwise change the implementation. + UBool append(const UChar *s, int32_t length, + uint8_t leadCC, uint8_t trailCC, + UErrorCode &errorCode); + UBool appendBMP(UChar c, uint8_t cc, UErrorCode &errorCode) { + if(remainingCapacity==0 && !resize(1, errorCode)) { + return FALSE; + } + if(lastCC<=cc || cc==0) { + *limit++=c; + lastCC=cc; + if(cc<=1) { + reorderStart=limit; + } + } else { + insert(c, cc); + } + --remainingCapacity; + return TRUE; + } + UBool appendZeroCC(UChar32 c, UErrorCode &errorCode); + UBool appendZeroCC(const UChar *s, const UChar *sLimit, UErrorCode &errorCode); + void remove(); + void removeSuffix(int32_t suffixLength); + void setReorderingLimit(UChar *newLimit) { + remainingCapacity+=(int32_t)(limit-newLimit); + reorderStart=limit=newLimit; + lastCC=0; + } + void copyReorderableSuffixTo(UnicodeString &s) const { + s.setTo(reorderStart, (int32_t)(limit-reorderStart)); + } +private: + /* + * TODO: Revisit whether it makes sense to track reorderStart. + * It is set to after the last known character with cc<=1, + * which stops previousCC() before it reads that character and looks up its cc. + * previousCC() is normally only called from insert(). + * In other words, reorderStart speeds up the insertion of a combining mark + * into a multi-combining mark sequence where it does not belong at the end. + * This might not be worth the trouble. + * On the other hand, it's not a huge amount of trouble. + * + * We probably need it for UNORM_SIMPLE_APPEND. + */ + + UBool appendSupplementary(UChar32 c, uint8_t cc, UErrorCode &errorCode); + void insert(UChar32 c, uint8_t cc); + static void writeCodePoint(UChar *p, UChar32 c) { + if(c<=0xffff) { + *p=(UChar)c; + } else { + p[0]=U16_LEAD(c); + p[1]=U16_TRAIL(c); + } + } + UBool resize(int32_t appendLength, UErrorCode &errorCode); + + const Normalizer2Impl &impl; + UnicodeString &str; + UChar *start, *reorderStart, *limit; + int32_t remainingCapacity; + uint8_t lastCC; + + // private backward iterator + void setIterator() { codePointStart=limit; } + void skipPrevious(); // Requires start<codePointStart. + uint8_t previousCC(); // Returns 0 if there is no previous character. + + UChar *codePointStart, *codePointLimit; +}; + +class U_COMMON_API Normalizer2Impl : public UMemory { +public: + Normalizer2Impl() : memory(NULL), normTrie(NULL) { + fcdTrieSingleton.fInstance=NULL; + canonIterDataSingleton.fInstance=NULL; + } + ~Normalizer2Impl(); + + void load(const char *packageName, const char *name, UErrorCode &errorCode); + + void addPropertyStarts(const USetAdder *sa, UErrorCode &errorCode) const; + void addCanonIterPropertyStarts(const USetAdder *sa, UErrorCode &errorCode) const; + + // low-level properties ------------------------------------------------ *** + + const UTrie2 *getNormTrie() const { return normTrie; } + const UTrie2 *getFCDTrie(UErrorCode &errorCode) const ; + + UBool ensureCanonIterData(UErrorCode &errorCode) const; + + uint16_t getNorm16(UChar32 c) const { return UTRIE2_GET16(normTrie, c); } + + UNormalizationCheckResult getCompQuickCheck(uint16_t norm16) const { + if(norm16<minNoNo || MIN_YES_YES_WITH_CC<=norm16) { + return UNORM_YES; + } else if(minMaybeYes<=norm16) { + return UNORM_MAYBE; + } else { + return UNORM_NO; + } + } + UBool isCompNo(uint16_t norm16) const { return minNoNo<=norm16 && norm16<minMaybeYes; } + UBool isDecompYes(uint16_t norm16) const { return norm16<minYesNo || minMaybeYes<=norm16; } + + uint8_t getCC(uint16_t norm16) const { + if(norm16>=MIN_NORMAL_MAYBE_YES) { + return (uint8_t)norm16; + } + if(norm16<minNoNo || limitNoNo<=norm16) { + return 0; + } + return getCCFromNoNo(norm16); + } + static uint8_t getCCFromYesOrMaybe(uint16_t norm16) { + return norm16>=MIN_NORMAL_MAYBE_YES ? (uint8_t)norm16 : 0; + } + + uint16_t getFCD16(UChar32 c) const { return UTRIE2_GET16(fcdTrie(), c); } + uint16_t getFCD16FromSingleLead(UChar c) const { + return UTRIE2_GET16_FROM_U16_SINGLE_LEAD(fcdTrie(), c); + } + uint16_t getFCD16FromSupplementary(UChar32 c) const { + return UTRIE2_GET16_FROM_SUPP(fcdTrie(), c); + } + uint16_t getFCD16FromSurrogatePair(UChar c, UChar c2) const { + return getFCD16FromSupplementary(U16_GET_SUPPLEMENTARY(c, c2)); + } + + void setFCD16FromNorm16(UChar32 start, UChar32 end, uint16_t norm16, + UTrie2 *newFCDTrie, UErrorCode &errorCode) const; + + void makeCanonIterDataFromNorm16(UChar32 start, UChar32 end, uint16_t norm16, + CanonIterData &newData, UErrorCode &errorCode) const; + + /** + * Get the decomposition for one code point. + * @param c code point + * @param buffer out-only buffer for algorithmic decompositions + * @param length out-only, takes the length of the decomposition, if any + * @return pointer to the decomposition, or NULL if none + */ + const UChar *getDecomposition(UChar32 c, UChar buffer[4], int32_t &length) const; + + UBool isCanonSegmentStarter(UChar32 c) const; + UBool getCanonStartSet(UChar32 c, UnicodeSet &set) const; + + enum { + MIN_CCC_LCCC_CP=0x300 + }; + + enum { + MIN_YES_YES_WITH_CC=0xff01, + JAMO_VT=0xff00, + MIN_NORMAL_MAYBE_YES=0xfe00, + JAMO_L=1, + MAX_DELTA=0x40 + }; + + enum { + // Byte offsets from the start of the data, after the generic header. + IX_NORM_TRIE_OFFSET, + IX_EXTRA_DATA_OFFSET, + IX_RESERVED2_OFFSET, + IX_RESERVED3_OFFSET, + IX_RESERVED4_OFFSET, + IX_RESERVED5_OFFSET, + IX_RESERVED6_OFFSET, + IX_TOTAL_SIZE, + + // Code point thresholds for quick check codes. + IX_MIN_DECOMP_NO_CP, + IX_MIN_COMP_NO_MAYBE_CP, + + // Norm16 value thresholds for quick check combinations and types of extra data. + IX_MIN_YES_NO, + IX_MIN_NO_NO, + IX_LIMIT_NO_NO, + IX_MIN_MAYBE_YES, + + IX_RESERVED14, + IX_RESERVED15, + IX_COUNT + }; + + enum { + MAPPING_HAS_CCC_LCCC_WORD=0x80, + MAPPING_PLUS_COMPOSITION_LIST=0x40, + MAPPING_NO_COMP_BOUNDARY_AFTER=0x20, + MAPPING_LENGTH_MASK=0x1f + }; + + enum { + COMP_1_LAST_TUPLE=0x8000, + COMP_1_TRIPLE=1, + COMP_1_TRAIL_LIMIT=0x3400, + COMP_1_TRAIL_MASK=0x7ffe, + COMP_1_TRAIL_SHIFT=9, // 10-1 for the "triple" bit + COMP_2_TRAIL_SHIFT=6, + COMP_2_TRAIL_MASK=0xffc0 + }; + + // higher-level functionality ------------------------------------------ *** + + const UChar *decompose(const UChar *src, const UChar *limit, + ReorderingBuffer *buffer, UErrorCode &errorCode) const; + void decomposeAndAppend(const UChar *src, const UChar *limit, + UBool doDecompose, + UnicodeString &safeMiddle, + ReorderingBuffer &buffer, + UErrorCode &errorCode) const; + UBool compose(const UChar *src, const UChar *limit, + UBool onlyContiguous, + UBool doCompose, + ReorderingBuffer &buffer, + UErrorCode &errorCode) const; + const UChar *composeQuickCheck(const UChar *src, const UChar *limit, + UBool onlyContiguous, + UNormalizationCheckResult *pQCResult) const; + void composeAndAppend(const UChar *src, const UChar *limit, + UBool doCompose, + UBool onlyContiguous, + UnicodeString &safeMiddle, + ReorderingBuffer &buffer, + UErrorCode &errorCode) const; + const UChar *makeFCD(const UChar *src, const UChar *limit, + ReorderingBuffer *buffer, UErrorCode &errorCode) const; + void makeFCDAndAppend(const UChar *src, const UChar *limit, + UBool doMakeFCD, + UnicodeString &safeMiddle, + ReorderingBuffer &buffer, + UErrorCode &errorCode) const; + + UBool hasDecompBoundary(UChar32 c, UBool before) const; + UBool isDecompInert(UChar32 c) const { return isDecompYesAndZeroCC(getNorm16(c)); } + + UBool hasCompBoundaryBefore(UChar32 c) const { + return c<minCompNoMaybeCP || hasCompBoundaryBefore(c, getNorm16(c)); + } + UBool hasCompBoundaryAfter(UChar32 c, UBool onlyContiguous, UBool testInert) const; + + UBool hasFCDBoundaryBefore(UChar32 c) const { return c<MIN_CCC_LCCC_CP || getFCD16(c)<=0xff; } + UBool hasFCDBoundaryAfter(UChar32 c) const { + uint16_t fcd16=getFCD16(c); + return fcd16<=1 || (fcd16&0xff)==0; + } + UBool isFCDInert(UChar32 c) const { return getFCD16(c)<=1; } +private: + static UBool U_CALLCONV + isAcceptable(void *context, const char *type, const char *name, const UDataInfo *pInfo); + + UBool isMaybe(uint16_t norm16) const { return minMaybeYes<=norm16 && norm16<=JAMO_VT; } + UBool isMaybeOrNonZeroCC(uint16_t norm16) const { return norm16>=minMaybeYes; } + static UBool isInert(uint16_t norm16) { return norm16==0; } + // static UBool isJamoL(uint16_t norm16) const { return norm16==1; } + static UBool isJamoVT(uint16_t norm16) { return norm16==JAMO_VT; } + UBool isHangul(uint16_t norm16) const { return norm16==minYesNo; } + UBool isCompYesAndZeroCC(uint16_t norm16) const { return norm16<minNoNo; } + // UBool isCompYes(uint16_t norm16) const { + // return norm16>=MIN_YES_YES_WITH_CC || norm16<minNoNo; + // } + // UBool isCompYesOrMaybe(uint16_t norm16) const { + // return norm16<minNoNo || minMaybeYes<=norm16; + // } + // UBool hasZeroCCFromDecompYes(uint16_t norm16) const { + // return norm16<=MIN_NORMAL_MAYBE_YES || norm16==JAMO_VT; + // } + UBool isDecompYesAndZeroCC(uint16_t norm16) const { + return norm16<minYesNo || + norm16==JAMO_VT || + (minMaybeYes<=norm16 && norm16<=MIN_NORMAL_MAYBE_YES); + } + /** + * A little faster and simpler than isDecompYesAndZeroCC() but does not include + * the MaybeYes which combine-forward and have ccc=0. + * (Standard Unicode 5.2 normalization does not have such characters.) + */ + UBool isMostDecompYesAndZeroCC(uint16_t norm16) const { + return norm16<minYesNo || norm16==MIN_NORMAL_MAYBE_YES || norm16==JAMO_VT; + } + UBool isDecompNoAlgorithmic(uint16_t norm16) const { return norm16>=limitNoNo; } + + // For use with isCompYes(). + // Perhaps the compiler can combine the two tests for MIN_YES_YES_WITH_CC. + // static uint8_t getCCFromYes(uint16_t norm16) { + // return norm16>=MIN_YES_YES_WITH_CC ? (uint8_t)norm16 : 0; + // } + uint8_t getCCFromNoNo(uint16_t norm16) const { + const uint16_t *mapping=getMapping(norm16); + if(*mapping&MAPPING_HAS_CCC_LCCC_WORD) { + return (uint8_t)mapping[1]; + } else { + return 0; + } + } + // requires that the [cpStart..cpLimit[ character passes isCompYesAndZeroCC() + uint8_t getTrailCCFromCompYesAndZeroCC(const UChar *cpStart, const UChar *cpLimit) const; + + // Requires algorithmic-NoNo. + UChar32 mapAlgorithmic(UChar32 c, uint16_t norm16) const { + return c+norm16-(minMaybeYes-MAX_DELTA-1); + } + + // Requires minYesNo<norm16<limitNoNo. + const uint16_t *getMapping(uint16_t norm16) const { return extraData+norm16; } + const uint16_t *getCompositionsListForDecompYes(uint16_t norm16) const { + if(norm16==0 || MIN_NORMAL_MAYBE_YES<=norm16) { + return NULL; + } else if(norm16<minMaybeYes) { + return extraData+norm16; // for yesYes; if Jamo L: harmless empty list + } else { + return maybeYesCompositions+norm16-minMaybeYes; + } + } + const uint16_t *getCompositionsListForComposite(uint16_t norm16) const { + const uint16_t *list=extraData+norm16; // composite has both mapping & compositions list + return list+ // mapping pointer + 1+ // +1 to skip the first unit with the mapping lenth + (*list&MAPPING_LENGTH_MASK)+ // + mapping length + ((*list>>7)&1); // +1 if MAPPING_HAS_CCC_LCCC_WORD + } + /** + * @param c code point must have compositions + * @return compositions list pointer + */ + const uint16_t *getCompositionsList(uint16_t norm16) const { + return isDecompYes(norm16) ? + getCompositionsListForDecompYes(norm16) : + getCompositionsListForComposite(norm16); + } + + const UChar *copyLowPrefixFromNulTerminated(const UChar *src, + UChar32 minNeedDataCP, + ReorderingBuffer *buffer, + UErrorCode &errorCode) const; + UBool decomposeShort(const UChar *src, const UChar *limit, + ReorderingBuffer &buffer, UErrorCode &errorCode) const; + UBool decompose(UChar32 c, uint16_t norm16, + ReorderingBuffer &buffer, UErrorCode &errorCode) const; + + static int32_t combine(const uint16_t *list, UChar32 trail); + void addComposites(const uint16_t *list, UnicodeSet &set) const; + void recompose(ReorderingBuffer &buffer, int32_t recomposeStartIndex, + UBool onlyContiguous) const; + + UBool hasCompBoundaryBefore(UChar32 c, uint16_t norm16) const; + const UChar *findPreviousCompBoundary(const UChar *start, const UChar *p) const; + const UChar *findNextCompBoundary(const UChar *p, const UChar *limit) const; + + const UTrie2 *fcdTrie() const { return (const UTrie2 *)fcdTrieSingleton.fInstance; } + + const UChar *findPreviousFCDBoundary(const UChar *start, const UChar *p) const; + const UChar *findNextFCDBoundary(const UChar *p, const UChar *limit) const; + + int32_t getCanonValue(UChar32 c) const; + const UnicodeSet &getCanonStartSet(int32_t n) const; + + UDataMemory *memory; + UVersionInfo dataVersion; + + // Code point thresholds for quick check codes. + UChar32 minDecompNoCP; + UChar32 minCompNoMaybeCP; + + // Norm16 value thresholds for quick check combinations and types of extra data. + uint16_t minYesNo; + uint16_t minNoNo; + uint16_t limitNoNo; + uint16_t minMaybeYes; + + UTrie2 *normTrie; + const uint16_t *maybeYesCompositions; + const uint16_t *extraData; // mappings and/or compositions for yesYes, yesNo & noNo characters + + SimpleSingleton fcdTrieSingleton; + SimpleSingleton canonIterDataSingleton; +}; + +// bits in canonIterData +#define CANON_NOT_SEGMENT_STARTER 0x80000000 +#define CANON_HAS_COMPOSITIONS 0x40000000 +#define CANON_HAS_SET 0x200000 +#define CANON_VALUE_MASK 0x1fffff + +/** + * ICU-internal shortcut for quick access to standard Unicode normalization. + */ +class U_COMMON_API Normalizer2Factory { +public: + static const Normalizer2 *getNFCInstance(UErrorCode &errorCode); + static const Normalizer2 *getNFDInstance(UErrorCode &errorCode); + static const Normalizer2 *getFCDInstance(UErrorCode &errorCode); + static const Normalizer2 *getFCCInstance(UErrorCode &errorCode); + static const Normalizer2 *getNFKCInstance(UErrorCode &errorCode); + static const Normalizer2 *getNFKDInstance(UErrorCode &errorCode); + static const Normalizer2 *getNFKC_CFInstance(UErrorCode &errorCode); + static const Normalizer2 *getNoopInstance(UErrorCode &errorCode); + + static const Normalizer2 *getInstance(UNormalizationMode mode, UErrorCode &errorCode); + + static const Normalizer2Impl *getNFCImpl(UErrorCode &errorCode); + static const Normalizer2Impl *getNFKCImpl(UErrorCode &errorCode); + static const Normalizer2Impl *getNFKC_CFImpl(UErrorCode &errorCode); + + // Get the Impl instance of the Normalizer2. + // Must be used only when it is known that norm2 is a Normalizer2WithImpl instance. + static const Normalizer2Impl *getImpl(const Normalizer2 *norm2); + + static const UTrie2 *getFCDTrie(UErrorCode &errorCode); +private: + Normalizer2Factory(); // No instantiation. +}; + +U_NAMESPACE_END + +U_CAPI int32_t U_EXPORT2 +unorm2_swap(const UDataSwapper *ds, + const void *inData, int32_t length, void *outData, + UErrorCode *pErrorCode); + +/** + * Get the NF*_QC property for a code point, for u_getIntPropertyValue(). + * @internal + */ +U_CFUNC UNormalizationCheckResult U_EXPORT2 +unorm_getQuickCheck(UChar32 c, UNormalizationMode mode); + +/** + * Internal API, used by collation code. + * Get access to the internal FCD trie table to be able to perform + * incremental, per-code unit, FCD checks in collation. + * One pointer is sufficient because the trie index values are offset + * by the index size, so that the same pointer is used to access the trie data. + * Code points at fcdHighStart and above have a zero FCD value. + * @internal + */ +U_CAPI const uint16_t * U_EXPORT2 +unorm_getFCDTrieIndex(UChar32 &fcdHighStart, UErrorCode *pErrorCode); + +/** + * Internal API, used by collation code. + * Get the FCD value for a code unit, with + * bits 15..8 lead combining class + * bits 7..0 trail combining class + * + * If c is a lead surrogate and the value is not 0, + * then some of c's associated supplementary code points have a non-zero FCD value. + * + * @internal + */ +static inline uint16_t +unorm_getFCD16(const uint16_t *fcdTrieIndex, UChar c) { + return fcdTrieIndex[_UTRIE2_INDEX_FROM_U16_SINGLE_LEAD(fcdTrieIndex, c)]; +} + +/** + * Internal API, used by collation code. + * Get the FCD value of the next code point (post-increment), with + * bits 15..8 lead combining class + * bits 7..0 trail combining class + * + * @internal + */ +static inline uint16_t +unorm_nextFCD16(const uint16_t *fcdTrieIndex, UChar32 fcdHighStart, + const UChar *&s, const UChar *limit) { + UChar32 c=*s++; + uint16_t fcd=fcdTrieIndex[_UTRIE2_INDEX_FROM_U16_SINGLE_LEAD(fcdTrieIndex, c)]; + if(fcd!=0 && U16_IS_LEAD(c)) { + UChar c2; + if(s!=limit && U16_IS_TRAIL(c2=*s)) { + ++s; + c=U16_GET_SUPPLEMENTARY(c, c2); + if(c<fcdHighStart) { + fcd=fcdTrieIndex[_UTRIE2_INDEX_FROM_SUPP(fcdTrieIndex, c)]; + } else { + fcd=0; + } + } else /* unpaired lead surrogate */ { + fcd=0; + } + } + return fcd; +} + +/** + * Internal API, used by collation code. + * Get the FCD value of the previous code point (pre-decrement), with + * bits 15..8 lead combining class + * bits 7..0 trail combining class + * + * @internal + */ +static inline uint16_t +unorm_prevFCD16(const uint16_t *fcdTrieIndex, UChar32 fcdHighStart, + const UChar *start, const UChar *&s) { + UChar32 c=*--s; + uint16_t fcd; + if(!U16_IS_SURROGATE(c)) { + fcd=fcdTrieIndex[_UTRIE2_INDEX_FROM_U16_SINGLE_LEAD(fcdTrieIndex, c)]; + } else { + UChar c2; + if(U16_IS_SURROGATE_TRAIL(c) && s!=start && U16_IS_LEAD(c2=*(s-1))) { + --s; + c=U16_GET_SUPPLEMENTARY(c2, c); + if(c<fcdHighStart) { + fcd=fcdTrieIndex[_UTRIE2_INDEX_FROM_SUPP(fcdTrieIndex, c)]; + } else { + fcd=0; + } + } else /* unpaired surrogate */ { + fcd=0; + } + } + return fcd; +} + +/** + * Format of Normalizer2 .nrm data files. + * Format version 1.0. + * + * Normalizer2 .nrm data files provide data for the Unicode Normalization algorithms. + * ICU ships with data files for standard Unicode Normalization Forms + * NFC and NFD (nfc.nrm), NFKC and NFKD (nfkc.nrm) and NFKC_Casefold (nfkc_cf.nrm). + * Custom (application-specific) data can be built into additional .nrm files + * with the gennorm2 build tool. + * + * Normalizer2.getInstance() causes a .nrm file to be loaded, unless it has been + * cached already. Internally, Normalizer2Impl.load() reads the .nrm file. + * + * A .nrm file begins with a standard ICU data file header + * (DataHeader, see ucmndata.h and unicode/udata.h). + * The UDataInfo.dataVersion field usually contains the Unicode version + * for which the data was generated. + * + * After the header, the file contains the following parts. + * Constants are defined as enum values of the Normalizer2Impl class. + * + * Many details of the data structures are described in the design doc + * which is at http://site.icu-project.org/design/normalization/custom + * + * int32_t indexes[indexesLength]; -- indexesLength=indexes[IX_NORM_TRIE_OFFSET]/4; + * + * The first eight indexes are byte offsets in ascending order. + * Each byte offset marks the start of the next part in the data file, + * and the end of the previous one. + * When two consecutive byte offsets are the same, then the corresponding part is empty. + * Byte offsets are offsets from after the header, + * that is, from the beginning of the indexes[]. + * Each part starts at an offset with proper alignment for its data. + * If necessary, the previous part may include padding bytes to achieve this alignment. + * + * minDecompNoCP=indexes[IX_MIN_DECOMP_NO_CP] is the lowest code point + * with a decomposition mapping, that is, with NF*D_QC=No. + * minCompNoMaybeCP=indexes[IX_MIN_COMP_NO_MAYBE_CP] is the lowest code point + * with NF*C_QC=No (has a one-way mapping) or Maybe (combines backward). + * + * The next four indexes are thresholds of 16-bit trie values for ranges of + * values indicating multiple normalization properties. + * minYesNo=indexes[IX_MIN_YES_NO]; + * minNoNo=indexes[IX_MIN_NO_NO]; + * limitNoNo=indexes[IX_LIMIT_NO_NO]; + * minMaybeYes=indexes[IX_MIN_MAYBE_YES]; + * See the normTrie description below and the design doc for details. + * + * UTrie2 normTrie; -- see utrie2_impl.h and utrie2.h + * + * The trie holds the main normalization data. Each code point is mapped to a 16-bit value. + * Rather than using independent bits in the value (which would require more than 16 bits), + * information is extracted primarily via range checks. + * For example, a 16-bit value norm16 in the range minYesNo<=norm16<minNoNo + * means that the character has NF*C_QC=Yes and NF*D_QC=No properties, + * which means it has a two-way (round-trip) decomposition mapping. + * Values in the range 2<=norm16<limitNoNo are also directly indexes into the extraData + * pointing to mappings, composition lists, or both. + * Value norm16==0 means that the character is normalization-inert, that is, + * it does not have a mapping, does not participate in composition, has a zero + * canonical combining class, and forms a boundary where text before it and after it + * can be normalized independently. + * For details about how multiple properties are encoded in 16-bit values + * see the design doc. + * Note that the encoding cannot express all combinations of the properties involved; + * it only supports those combinations that are allowed by + * the Unicode Normalization algorithms. Details are in the design doc as well. + * The gennorm2 tool only builds .nrm files for data that conforms to the limitations. + * + * The trie has a value for each lead surrogate code unit representing the "worst case" + * properties of the 1024 supplementary characters whose UTF-16 form starts with + * the lead surrogate. If all of the 1024 supplementary characters are normalization-inert, + * then their lead surrogate code unit has the trie value 0. + * When the lead surrogate unit's value exceeds the quick check minimum during processing, + * the properties for the full supplementary code point need to be looked up. + * + * uint16_t maybeYesCompositions[MIN_NORMAL_MAYBE_YES-minMaybeYes]; + * uint16_t extraData[]; + * + * There is only one byte offset for the end of these two arrays. + * The split between them is given by the constant and variable mentioned above. + * + * The maybeYesCompositions array contains composition lists for characters that + * combine both forward (as starters in composition pairs) + * and backward (as trailing characters in composition pairs). + * Such characters do not occur in Unicode 5.2 but are allowed by + * the Unicode Normalization algorithms. + * If there are no such characters, then minMaybeYes==MIN_NORMAL_MAYBE_YES + * and the maybeYesCompositions array is empty. + * If there are such characters, then minMaybeYes is subtracted from their norm16 values + * to get the index into this array. + * + * The extraData array contains composition lists for "YesYes" characters, + * followed by mappings and optional composition lists for "YesNo" characters, + * followed by only mappings for "NoNo" characters. + * (Referring to pairs of NFC/NFD quick check values.) + * The norm16 values of those characters are directly indexes into the extraData array. + * + * The data structures for composition lists and mappings are described in the design doc. + */ + +#endif /* !UCONFIG_NO_NORMALIZATION */ +#endif /* __NORMALIZER2IMPL_H__ */ |