a968441ac2
X-SVN-Rev: 11264
686 lines
25 KiB
C
686 lines
25 KiB
C
/*
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*******************************************************************************
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*
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* Copyright (C) 2001-2002, International Business Machines
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* Corporation and others. All Rights Reserved.
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*
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*******************************************************************************
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* file name: unormimp.h
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* encoding: US-ASCII
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* tab size: 8 (not used)
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* indentation:4
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*
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* created on: 2001may25
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* created by: Markus W. Scherer
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*/
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#ifndef __UNORMIMP_H__
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#define __UNORMIMP_H__
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#include "unicode/utypes.h"
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#include "unicode/uiter.h"
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#include "unicode/unorm.h"
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#include "unicode/uset.h"
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#include "utrie.h"
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#include "ustr_imp.h"
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/*
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* This new implementation of the normalization code loads its data from
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* unorm.dat, which is generated with the gennorm tool.
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* The format of that file is described at the end of this file.
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*/
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/* norm32 value constants */
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enum {
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/* quick check flags 0..3 set mean "no" for their forms */
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_NORM_QC_NFC=0x11, /* no|maybe */
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_NORM_QC_NFKC=0x22, /* no|maybe */
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_NORM_QC_NFD=4, /* no */
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_NORM_QC_NFKD=8, /* no */
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_NORM_QC_ANY_NO=0xf,
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/* quick check flags 4..5 mean "maybe" for their forms; test flags>=_NORM_QC_MAYBE */
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_NORM_QC_MAYBE=0x10,
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_NORM_QC_ANY_MAYBE=0x30,
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_NORM_QC_MASK=0x3f,
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_NORM_COMBINES_FWD=0x40,
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_NORM_COMBINES_BACK=0x80,
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_NORM_COMBINES_ANY=0xc0,
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_NORM_CC_SHIFT=8, /* UnicodeData.txt combining class in bits 15..8 */
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_NORM_CC_MASK=0xff00,
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_NORM_EXTRA_SHIFT=16, /* 16 bits for the index to UChars and other extra data */
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_NORM_EXTRA_INDEX_TOP=0xfc00, /* start of surrogate specials after shift */
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_NORM_EXTRA_SURROGATE_MASK=0x3ff,
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_NORM_EXTRA_SURROGATE_TOP=0x3f0, /* hangul etc. */
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_NORM_EXTRA_HANGUL=_NORM_EXTRA_SURROGATE_TOP,
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_NORM_EXTRA_JAMO_L, /* ### not used */
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_NORM_EXTRA_JAMO_V,
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_NORM_EXTRA_JAMO_T
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};
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/* norm32 value constants using >16 bits */
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#define _NORM_MIN_SPECIAL 0xfc000000
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#define _NORM_SURROGATES_TOP 0xfff00000
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#define _NORM_MIN_HANGUL 0xfff00000
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#define _NORM_MIN_JAMO_V 0xfff20000
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#define _NORM_JAMO_V_TOP 0xfff30000
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/* value constants for auxTrie */
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enum {
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_NORM_AUX_COMP_EX_SHIFT=10,
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_NORM_AUX_UNSAFE_SHIFT=11,
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_NORM_AUX_NFC_SKIPPABLE_F_SHIFT=12
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};
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#define _NORM_AUX_MAX_FNC ((int32_t)1<<_NORM_AUX_COMP_EX_SHIFT)
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#define _NORM_AUX_FNC_MASK (uint32_t)(_NORM_AUX_MAX_FNC-1)
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#define _NORM_AUX_COMP_EX_MASK ((uint32_t)1<<_NORM_AUX_COMP_EX_SHIFT)
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#define _NORM_AUX_UNSAFE_MASK ((uint32_t)1<<_NORM_AUX_UNSAFE_SHIFT)
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#define _NORM_AUX_NFC_SKIP_F_MASK ((uint32_t)1<<_NORM_AUX_NFC_SKIPPABLE_F_SHIFT)
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/* canonStartSets[0..31] contains indexes for what is in the array */
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enum {
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_NORM_SET_INDEX_CANON_SETS_LENGTH, /* number of uint16_t in canonical starter sets */
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_NORM_SET_INDEX_CANON_BMP_TABLE_LENGTH, /* number of uint16_t in the BMP search table (contains pairs) */
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_NORM_SET_INDEX_CANON_SUPP_TABLE_LENGTH,/* number of uint16_t in the supplementary search table (contains triplets) */
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_NORM_SET_INDEX_TOP=32 /* changing this requires a new formatVersion */
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};
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/* more constants for canonical starter sets */
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/* 14 bit indexes to canonical USerializedSets */
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#define _NORM_MAX_CANON_SETS 0x4000
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/* single-code point BMP sets are encoded directly in the search table except if result=0x4000..0x7fff */
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#define _NORM_CANON_SET_BMP_MASK 0xc000
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#define _NORM_CANON_SET_BMP_IS_INDEX 0x4000
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/* indexes[] value names */
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enum {
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_NORM_INDEX_TRIE_SIZE, /* number of bytes in normalization trie */
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_NORM_INDEX_UCHAR_COUNT, /* number of UChars in extra data */
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_NORM_INDEX_COMBINE_DATA_COUNT, /* number of uint16_t words for combining data */
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_NORM_INDEX_COMBINE_FWD_COUNT, /* number of code points that combine forward */
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_NORM_INDEX_COMBINE_BOTH_COUNT, /* number of code points that combine forward and backward */
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_NORM_INDEX_COMBINE_BACK_COUNT, /* number of code points that combine backward */
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_NORM_INDEX_MIN_NFC_NO_MAYBE, /* first code point with quick check NFC NO/MAYBE */
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_NORM_INDEX_MIN_NFKC_NO_MAYBE, /* first code point with quick check NFKC NO/MAYBE */
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_NORM_INDEX_MIN_NFD_NO_MAYBE, /* first code point with quick check NFD NO/MAYBE */
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_NORM_INDEX_MIN_NFKD_NO_MAYBE, /* first code point with quick check NFKD NO/MAYBE */
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_NORM_INDEX_FCD_TRIE_SIZE, /* number of bytes in FCD trie */
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_NORM_INDEX_AUX_TRIE_SIZE, /* number of bytes in the auxiliary trie */
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_NORM_INDEX_CANON_SET_COUNT, /* number of uint16_t in the array of serialized USet */
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_NORM_INDEX_TOP=32 /* changing this requires a new formatVersion */
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};
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enum {
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/* FCD check: everything below this code point is known to have a 0 lead combining class */
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_NORM_MIN_WITH_LEAD_CC=0x300
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};
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enum {
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/**
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* Bit 7 of the length byte for a decomposition string in extra data is
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* a flag indicating whether the decomposition string is
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* preceded by a 16-bit word with the leading and trailing cc
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* of the decomposition (like for A-umlaut);
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* if not, then both cc's are zero (like for compatibility ideographs).
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*/
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_NORM_DECOMP_FLAG_LENGTH_HAS_CC=0x80,
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/**
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* Bits 6..0 of the length byte contain the actual length.
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*/
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_NORM_DECOMP_LENGTH_MASK=0x7f
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};
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/* Korean Hangul and Jamo constants */
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enum {
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JAMO_L_BASE=0x1100, /* "lead" jamo */
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JAMO_V_BASE=0x1161, /* "vowel" jamo */
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JAMO_T_BASE=0x11a7, /* "trail" jamo */
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HANGUL_BASE=0xac00,
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JAMO_L_COUNT=19,
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JAMO_V_COUNT=21,
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JAMO_T_COUNT=28,
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HANGUL_COUNT=JAMO_L_COUNT*JAMO_V_COUNT*JAMO_T_COUNT
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};
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/* Constants for options flags for normalization. ### TODO prototype, see unorm.cpp */
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enum {
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/** Options bit 0, do not decompose Hangul syllables. @draft ICU 2.6 */
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UNORM_NX_HANGUL=1,
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/** Options bit 1, do not decompose CJK compatibility characters. @draft ICU 2.6 */
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UNORM_NX_CJK_COMPAT=2,
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/** Options bit 2, do not decompose a-umlaut, only for testing. @internal */
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UNORM_NX_A_UMLAUT=4,
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/**
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* Options bit set value to select Unicode 3.2 normalization (except NormalizationCorrections).
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* At most one Unicode version can be selected at a time.
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* @draft ICU 2.6
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*/
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UNORM_UNICODE_3_2=0x20
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};
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/**
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* Lowest-order bit number of unorm_compare() options bits corresponding to
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* normalization options bits.
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*
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* The options parameter for unorm_compare() uses most bits for
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* itself and for various comparison and folding flags.
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* The most significant bits, however, are shifted down and passed on
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* to the normalization implementation.
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* (options>>UNORM_COMPARE_NORM_OPTIONS_SHIFT)
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*
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* ### TODO prototype, see unorm.cpp
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* @draft ICU 2.6
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*/
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#define UNORM_COMPARE_NORM_OPTIONS_SHIFT 20
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/**
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* ### TODO prototype, see unorm.cpp
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* @draft ICU 2.6
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*/
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U_CAPI UNormalizationCheckResult U_EXPORT2
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unorm_quickCheckWithOptions(const UChar *src, int32_t srcLength,
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UNormalizationMode mode, int32_t options,
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UErrorCode *pErrorCode);
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/** ### TODO @draft ICU 2.6 */
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U_CAPI UBool U_EXPORT2
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unorm_isNormalizedWithOptions(const UChar *src, int32_t srcLength,
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UNormalizationMode mode, int32_t options,
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UErrorCode *pErrorCode);
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/**
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* Is the normalizer data loaded?
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* This is used internally before other internal normalizer functions
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* are called.
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* It saves this check in each of many normalization calls that
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* are made for, e.g., collation.
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*
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* @param pErrorCode as usual
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* @return boolean value for whether the normalization data is loaded
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*
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* @internal
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*/
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U_CAPI UBool U_EXPORT2
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unorm_haveData(UErrorCode *pErrorCode);
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/**
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* Internal API for normalizing.
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* Does not check for bad input.
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* @internal
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*/
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U_CAPI int32_t U_EXPORT2
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unorm_internalNormalize(UChar *dest, int32_t destCapacity,
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const UChar *src, int32_t srcLength,
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UNormalizationMode mode, int32_t options,
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UErrorCode *pErrorCode);
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/**
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* internal API, used by normlzr.cpp
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* @internal
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*/
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U_CAPI int32_t U_EXPORT2
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unorm_decompose(UChar *dest, int32_t destCapacity,
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const UChar *src, int32_t srcLength,
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UBool compat, int32_t options,
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UErrorCode *pErrorCode);
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/**
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* internal API, used by normlzr.cpp
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* @internal
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*/
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U_CAPI int32_t U_EXPORT2
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unorm_compose(UChar *dest, int32_t destCapacity,
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const UChar *src, int32_t srcLength,
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UBool compat, int32_t options,
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UErrorCode *pErrorCode);
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/**
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* Internal option for unorm_cmpEquivFold() for decomposing.
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* If not set, just do strcasecmp().
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* @internal
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*/
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#define _COMPARE_EQUIV 0x80000
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/**
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* Internal option for unorm_cmpEquivFold() for strncmp style.
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* If set, checks for both string length and terminating NUL.
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* @internal
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*/
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#define _STRNCMP_STYLE 0x1000
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/**
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* Internal API, used by u_strcasecmp() etc.
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* Compare strings for canonical equivalence (optional),
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* case-insensitively (optional),
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* in code point order or code unit order.
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* @internal
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*/
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U_CAPI int32_t U_EXPORT2
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unorm_cmpEquivFold(const UChar *s1, int32_t length1,
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const UChar *s2, int32_t length2,
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uint32_t options,
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UErrorCode *pErrorCode);
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/**
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* Internal API, used by collation code.
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* Get access to the internal FCD trie table to be able to perform
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* incremental, per-code unit, FCD checks in collation.
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* One pointer is sufficient because the trie index values are offset
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* by the index size, so that the same pointer is used to access the trie data.
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* @internal
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*/
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U_CAPI const uint16_t * U_EXPORT2
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unorm_getFCDTrie(UErrorCode *pErrorCode);
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#ifdef XP_CPLUSPLUS
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U_NAMESPACE_BEGIN
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/**
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* Internal API, used by collation code.
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* Get the FCD value for a code unit, with
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* bits 15..8 lead combining class
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* bits 7..0 trail combining class
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*
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* If c is a lead surrogate and the value is not 0,
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* then instead of combining classes the value
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* is used in unorm_getFCD16FromSurrogatePair() to get the real value
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* of the supplementary code point.
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*
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* @internal
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*/
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inline uint16_t
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unorm_getFCD16(const uint16_t *fcdTrieIndex, UChar c) {
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return
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fcdTrieIndex[
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(fcdTrieIndex[
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c>>UTRIE_SHIFT
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]<<UTRIE_INDEX_SHIFT)+
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(c&UTRIE_MASK)
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];
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}
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/**
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* Internal API, used by collation code.
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* Get the FCD value for a supplementary code point, with
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* bits 15..8 lead combining class
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* bits 7..0 trail combining class
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*
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* @param fcd16 The FCD value for the lead surrogate, not 0.
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* @param c2 The trail surrogate code unit.
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*
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* @internal
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*/
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inline uint16_t
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unorm_getFCD16FromSurrogatePair(const uint16_t *fcdTrieIndex, uint16_t fcd16, UChar c2) {
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return
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fcdTrieIndex[
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(fcdTrieIndex[
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(int32_t)fcd16+((c2&0x3ff)>>UTRIE_SHIFT)
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]<<UTRIE_INDEX_SHIFT)+
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(c2&UTRIE_MASK)
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];
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}
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U_NAMESPACE_END
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#endif
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/**
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* internal API, used by the canonical iterator
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* @internal
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*/
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U_CAPI int32_t U_EXPORT2
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unorm_getDecomposition(UChar32 c, UBool compat,
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UChar *dest, int32_t destCapacity);
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/**
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* internal API, used by uprops.cpp
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* @internal
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*/
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U_CAPI UBool U_EXPORT2
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unorm_internalIsFullCompositionExclusion(UChar32 c);
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/**
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* Internal API, used by enumeration of canonically equivalent strings
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* @internal
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*/
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U_CAPI UBool U_EXPORT2
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unorm_isCanonSafeStart(UChar32 c);
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/**
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* Internal API, used by enumeration of canonically equivalent strings
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* @internal
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*/
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U_CAPI UBool U_EXPORT2
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unorm_getCanonStartSet(UChar32 c, USerializedSet *fillSet);
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/**
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* Is c an NF<mode>-skippable code point? See unormimp.h.
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* @internal
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*/
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U_CAPI UBool U_EXPORT2
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unorm_isNFSkippable(UChar32 c, UNormalizationMode mode);
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/**
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* Enumerate each normalization data trie and add the
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* start of each range of same properties to the set.
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* @internal
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*/
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U_CAPI void U_EXPORT2
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unorm_addPropertyStarts(USet *set);
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/**
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* Description of the format of unorm.dat version 2.2.
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*
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* Main change from version 1 to version 2:
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* Use of new, common UTrie instead of normalization-specific tries.
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* Change to version 2.1: add third/auxiliary trie with associated data.
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* Change to version 2.2: add skippable (f) flag data (_NORM_AUX_NFC_SKIP_F_MASK).
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*
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* For more details of how to use the data structures see the code
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* in unorm.cpp (runtime normalization code) and
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* in gennorm.c and gennorm/store.c (build-time data generation).
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*
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* For the serialized format of UTrie see utrie.c/UTrieHeader.
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*
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* - Overall partition
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*
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* unorm.dat customarily begins with a UDataInfo structure, see udata.h and .c.
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* After that there are the following structures:
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*
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* uint16_t indexes[_NORM_INDEX_TOP]; -- _NORM_INDEX_TOP=32, see enum in this file
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*
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* UTrie normTrie; -- size in bytes=indexes[_NORM_INDEX_TRIE_SIZE]
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*
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* uint16_t extraData[extraDataTop]; -- extraDataTop=indexes[_NORM_INDEX_UCHAR_COUNT]
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* extraData[0] contains the number of units for
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* FC_NFKC_Closure (formatVersion>=2.1)
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*
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* uint16_t combiningTable[combiningTableTop]; -- combiningTableTop=indexes[_NORM_INDEX_COMBINE_DATA_COUNT]
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* combiningTableTop may include one 16-bit padding unit
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* to make sure that fcdTrie is 32-bit-aligned
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*
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* UTrie fcdTrie; -- size in bytes=indexes[_NORM_INDEX_FCD_TRIE_SIZE]
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*
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* UTrie auxTrie; -- size in bytes=indexes[_NORM_INDEX_AUX_TRIE_SIZE]
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*
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* uint16_t canonStartSets[canonStartSetsTop] -- canonStartSetsTop=indexes[_NORM_INDEX_CANON_SET_COUNT]
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* serialized USets and binary search tables, see below
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*
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*
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* The indexes array contains lengths and sizes of the following arrays and structures
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* as well as the following values:
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* indexes[_NORM_INDEX_COMBINE_FWD_COUNT]=combineFwdTop
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* -- one more than the highest combining index computed for forward-only-combining characters
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* indexes[_NORM_INDEX_COMBINE_BOTH_COUNT]=combineBothTop-combineFwdTop
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* -- number of combining indexes computed for both-ways-combining characters
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* indexes[_NORM_INDEX_COMBINE_BACK_COUNT]=combineBackTop-combineBothTop
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* -- number of combining indexes computed for backward-only-combining characters
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*
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* indexes[_NORM_INDEX_MIN_NF*_NO_MAYBE] (where *={ C, D, KC, KD })
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* -- first code point with a quick check NF* value of NO/MAYBE
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*
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*
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* - Tries
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*
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* The main structures are two UTrie tables ("compact arrays"),
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* each with one index array and one data array.
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* See utrie.h and utrie.c.
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*
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*
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* - Tries in unorm.dat
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*
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* The first trie (normTrie above)
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* provides data for the NF* quick checks and normalization.
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* The second trie (fcdTrie above) provides data just for FCD checks.
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*
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*
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* - norm32 data words from the first trie
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*
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* The norm32Table contains one 32-bit word "norm32" per code point.
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* It contains the following bit fields:
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* 31..16 extra data index, _NORM_EXTRA_SHIFT is used to shift this field down
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* if this index is <_NORM_EXTRA_INDEX_TOP then it is an index into
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* extraData[] where variable-length normalization data for this
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* code point is found
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* if this index is <_NORM_EXTRA_INDEX_TOP+_NORM_EXTRA_SURROGATE_TOP
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* then this is a norm32 for a leading surrogate, and the index
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* value is used together with the following trailing surrogate
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* code unit in the second trie access
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* if this index is >=_NORM_EXTRA_INDEX_TOP+_NORM_EXTRA_SURROGATE_TOP
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|
* then this is a norm32 for a "special" character,
|
|
* i.e., the character is a Hangul syllable or a Jamo
|
|
* see _NORM_EXTRA_HANGUL etc.
|
|
* generally, instead of extracting this index from the norm32 and
|
|
* comparing it with the above constants,
|
|
* the normalization code compares the entire norm32 value
|
|
* with _NORM_MIN_SPECIAL, _NORM_SURROGATES_TOP, _NORM_MIN_HANGUL etc.
|
|
*
|
|
* 15..8 combining class (cc) according to UnicodeData.txt
|
|
*
|
|
* 7..6 _NORM_COMBINES_ANY flags, used in composition to see if a character
|
|
* combines with any following or preceding character(s)
|
|
* at all
|
|
* 7 _NORM_COMBINES_BACK
|
|
* 6 _NORM_COMBINES_FWD
|
|
*
|
|
* 5..0 quick check flags, set for "no" or "maybe", with separate flags for
|
|
* each normalization form
|
|
* the higher bits are "maybe" flags; for NF*D there are no such flags
|
|
* the lower bits are "no" flags for all forms, in the same order
|
|
* as the "maybe" flags,
|
|
* which is (MSB to LSB): NFKD NFD NFKC NFC
|
|
* 5..4 _NORM_QC_ANY_MAYBE
|
|
* 3..0 _NORM_QC_ANY_NO
|
|
* see further related constants
|
|
*
|
|
*
|
|
* - Extra data per code point
|
|
*
|
|
* "Extra data" is referenced by the index in norm32.
|
|
* It is variable-length data. It is only present, and only those parts
|
|
* of it are, as needed for a given character.
|
|
* The norm32 extra data index is added to the beginning of extraData[]
|
|
* to get to a vector of 16-bit words with data at the following offsets:
|
|
*
|
|
* [-1] Combining index for composition.
|
|
* Stored only if norm32&_NORM_COMBINES_ANY .
|
|
* [0] Lengths of the canonical and compatibility decomposition strings.
|
|
* Stored only if there are decompositions, i.e.,
|
|
* if norm32&(_NORM_QC_NFD|_NORM_QC_NFKD)
|
|
* High byte: length of NFKD, or 0 if none
|
|
* Low byte: length of NFD, or 0 if none
|
|
* Each length byte also has another flag:
|
|
* Bit 7 of a length byte is set if there are non-zero
|
|
* combining classes (cc's) associated with the respective
|
|
* decomposition. If this flag is set, then the decomposition
|
|
* is preceded by a 16-bit word that contains the
|
|
* leading and trailing cc's.
|
|
* Bits 6..0 of a length byte are the length of the
|
|
* decomposition string, not counting the cc word.
|
|
* [1..n] NFD
|
|
* [n+1..] NFKD
|
|
*
|
|
* Each of the two decompositions consists of up to two parts:
|
|
* - The 16-bit words with the leading and trailing cc's.
|
|
* This is only stored if bit 7 of the corresponding length byte
|
|
* is set. In this case, at least one of the cc's is not zero.
|
|
* High byte: leading cc==cc of the first code point in the decomposition string
|
|
* Low byte: trailing cc==cc of the last code point in the decomposition string
|
|
* - The decomposition string in UTF-16, with length code units.
|
|
*
|
|
*
|
|
* - Combining indexes and combiningTable[]
|
|
*
|
|
* Combining indexes are stored at the [-1] offset of the extra data
|
|
* if the character combines forward or backward with any other characters.
|
|
* They are used for (re)composition in NF*C.
|
|
* Values of combining indexes are arranged according to whether a character
|
|
* combines forward, backward, or both ways:
|
|
* forward-only < both ways < backward-only
|
|
*
|
|
* The index values for forward-only and both-ways combining characters
|
|
* are indexes into the combiningTable[].
|
|
* The index values for backward-only combining characters are simply
|
|
* incremented from the preceding index values to be unique.
|
|
*
|
|
* In the combiningTable[], a variable-length list
|
|
* of variable-length (back-index, code point) pair entries is stored
|
|
* for each forward-combining character.
|
|
*
|
|
* These back-indexes are the combining indexes of both-ways or backward-only
|
|
* combining characters that the forward-combining character combines with.
|
|
*
|
|
* Each list is sorted in ascending order of back-indexes.
|
|
* Each list is terminated with the last back-index having bit 15 set.
|
|
*
|
|
* Each pair (back-index, code point) takes up either 2 or 3
|
|
* 16-bit words.
|
|
* The first word of a list entry is the back-index, with its bit 15 set if
|
|
* this is the last pair in the list.
|
|
*
|
|
* The second word contains flags in bits 15..13 that determine
|
|
* if there is a third word and how the combined character is encoded:
|
|
* 15 set if there is a third word in this list entry
|
|
* 14 set if the result is a supplementary character
|
|
* 13 set if the result itself combines forward
|
|
*
|
|
* According to these bits 15..14 of the second word,
|
|
* the result character is encoded as follows:
|
|
* 00 or 01 The result is <=0x1fff and stored in bits 12..0 of
|
|
* the second word.
|
|
* 10 The result is 0x2000..0xffff and stored in the third word.
|
|
* Bits 12..0 of the second word are not used.
|
|
* 11 The result is a supplementary character.
|
|
* Bits 9..0 of the leading surrogate are in bits 9..0 of
|
|
* the second word.
|
|
* Add 0xd800 to these bits to get the complete surrogate.
|
|
* Bits 12..10 of the second word are not used.
|
|
* The trailing surrogate is stored in the third word.
|
|
*
|
|
*
|
|
* - FCD trie
|
|
*
|
|
* The FCD trie is very simple.
|
|
* It is a folded trie with 16-bit data words.
|
|
* In each word, the high byte contains the leading cc of the character,
|
|
* and the low byte contains the trailing cc of the character.
|
|
* These cc's are the cc's of the first and last code points in the
|
|
* canonical decomposition of the character.
|
|
*
|
|
* Since all 16 bits are used for cc's, lead surrogates must be tested
|
|
* by checking the code unit instead of the trie data.
|
|
* This is done only if the 16-bit data word is not zero.
|
|
* If the code unit is a leading surrogate and the data word is not zero,
|
|
* then instead of cc's it contains the offset for the second trie lookup.
|
|
*
|
|
*
|
|
* - Auxiliary trie and data
|
|
*
|
|
* The auxiliary 16-bit trie contains data for additional properties.
|
|
* Bits
|
|
* 15..13 reserved
|
|
* 12 not NFC_Skippable (f) (formatVersion>=2.2)
|
|
* 11 flag: not a safe starter for canonical closure
|
|
* 10 composition exclusion
|
|
* 9.. 0 index into extraData[] to FC_NFKC_Closure string
|
|
* (not for lead surrogate),
|
|
* or lead surrogate offset (for lead surrogate, if 9..0 not zero)
|
|
*
|
|
* - FC_NFKC_Closure strings in extraData[]
|
|
*
|
|
* Strings are either stored as a single code unit or as the length
|
|
* followed by that many units.
|
|
* const UChar *s=extraData+(index from auxTrie data bits 9..0);
|
|
* int32_t length;
|
|
* if(*s<0xff00) {
|
|
* // s points to the single-unit string
|
|
* length=1;
|
|
* } else {
|
|
* length=*s&0xff;
|
|
* ++s;
|
|
* }
|
|
*
|
|
* Conditions for "NF* Skippable" from Mark Davis' com.ibm.text.UCD.NFSkippable:
|
|
* (used in NormalizerTransliterator)
|
|
*
|
|
* A skippable character is
|
|
* a) unassigned, or ALL of the following:
|
|
* b) of combining class 0.
|
|
* c) not decomposed by this normalization form.
|
|
* AND if NFC or NFKC,
|
|
* d) can never compose with a previous character.
|
|
* e) can never compose with a following character.
|
|
* f) can never change if another character is added.
|
|
* Example: a-breve might satisfy all but f, but if you
|
|
* add an ogonek it changes to a-ogonek + breve
|
|
*
|
|
* a)..e) must be tested from norm32.
|
|
* Since f) is more complicated, the (not-)NFC_Skippable flag (f) is built
|
|
* into the auxiliary trie.
|
|
* The same bit is used for NFC and NFKC; (c) differs for them.
|
|
* As usual, we build the "not skippable" flags so that unassigned
|
|
* code points get a 0 bit.
|
|
* This bit is only valid after (a)..(e) test FALSE; test NFD_NO before (f) as well.
|
|
* Test Hangul LV syllables entirely in code.
|
|
*
|
|
*
|
|
* - structure inside canonStartSets[]
|
|
*
|
|
* This array maps from code points c to sets of code points (USerializedSet).
|
|
* The result sets are the code points whose canonical decompositions start
|
|
* with c.
|
|
*
|
|
* canonStartSets[] contains the following sub-arrays:
|
|
*
|
|
* indexes[_NORM_SET_INDEX_TOP]
|
|
* - contains lengths of sub-arrays etc.
|
|
*
|
|
* startSets[indexes[_NORM_SET_INDEX_CANON_SETS_LENGTH]-_NORM_SET_INDEX_TOP]
|
|
* - contains serialized sets (USerializedSet) of canonical starters for
|
|
* enumerating canonically equivalent strings
|
|
* indexes[_NORM_SET_INDEX_CANON_SETS_LENGTH] includes _NORM_SET_INDEX_TOP
|
|
* for details about the structure see uset.c
|
|
*
|
|
* bmpTable[indexes[_NORM_SET_INDEX_CANON_BMP_TABLE_LENGTH]]
|
|
* - a sorted search table for BMP code points whose results are
|
|
* either indexes to USerializedSets or single code points for
|
|
* single-code point sets;
|
|
* each entry is a pair of { code point, result } with result=(binary) yy xxxxxx xxxxxxxx
|
|
* if yy==01 then there is a USerializedSet at canonStartSets+x
|
|
* else build a USerializedSet with result as the single code point
|
|
*
|
|
* suppTable[indexes[_NORM_SET_INDEX_CANON_SUPP_TABLE_LENGTH]]
|
|
* - a sorted search table for supplementary code points whose results are
|
|
* either indexes to USerializedSets or single code points for
|
|
* single-code point sets;
|
|
* each entry is a triplet of { high16(cp), low16(cp), result }
|
|
* each code point's high-word may contain extra data in bits 15..5:
|
|
* if the high word has bit 15 set, then build a set with a single code point
|
|
* which is (((high16(cp)&0x1f00)<<8)|result;
|
|
* else there is a USerializedSet at canonStartSets+result
|
|
*/
|
|
|
|
#endif
|