scuffed-code/icu4c/source/i18n/collation.h
2017-01-20 00:20:31 +00:00

501 lines
19 KiB
C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 2010-2015, International Business Machines
* Corporation and others. All Rights Reserved.
*******************************************************************************
* collation.h
*
* created on: 2010oct27
* created by: Markus W. Scherer
*/
#ifndef __COLLATION_H__
#define __COLLATION_H__
#include "unicode/utypes.h"
#if !UCONFIG_NO_COLLATION
U_NAMESPACE_BEGIN
/**
* Collation v2 basic definitions and static helper functions.
*
* Data structures except for expansion tables store 32-bit CEs which are
* either specials (see tags below) or are compact forms of 64-bit CEs.
*/
class U_I18N_API Collation {
public:
// Special sort key bytes for all levels.
static const uint8_t TERMINATOR_BYTE = 0;
static const uint8_t LEVEL_SEPARATOR_BYTE = 1;
/** The secondary/tertiary lower limit for tailoring before any root elements. */
static const uint32_t BEFORE_WEIGHT16 = 0x0100;
/**
* Merge-sort-key separator.
* Same as the unique primary and identical-level weights of U+FFFE.
* Must not be used as primary compression low terminator.
* Otherwise usable.
*/
static const uint8_t MERGE_SEPARATOR_BYTE = 2;
static const uint32_t MERGE_SEPARATOR_PRIMARY = 0x02000000; // U+FFFE
static const uint32_t MERGE_SEPARATOR_CE32 = 0x02000505; // U+FFFE
/**
* Primary compression low terminator, must be greater than MERGE_SEPARATOR_BYTE.
* Reserved value in primary second byte if the lead byte is compressible.
* Otherwise usable in all CE weight bytes.
*/
static const uint8_t PRIMARY_COMPRESSION_LOW_BYTE = 3;
/**
* Primary compression high terminator.
* Reserved value in primary second byte if the lead byte is compressible.
* Otherwise usable in all CE weight bytes.
*/
static const uint8_t PRIMARY_COMPRESSION_HIGH_BYTE = 0xff;
/** Default secondary/tertiary weight lead byte. */
static const uint8_t COMMON_BYTE = 5;
static const uint32_t COMMON_WEIGHT16 = 0x0500;
/** Middle 16 bits of a CE with a common secondary weight. */
static const uint32_t COMMON_SECONDARY_CE = 0x05000000;
/** Lower 16 bits of a CE with a common tertiary weight. */
static const uint32_t COMMON_TERTIARY_CE = 0x0500;
/** Lower 32 bits of a CE with common secondary and tertiary weights. */
static const uint32_t COMMON_SEC_AND_TER_CE = 0x05000500;
static const uint32_t SECONDARY_MASK = 0xffff0000;
static const uint32_t CASE_MASK = 0xc000;
static const uint32_t SECONDARY_AND_CASE_MASK = SECONDARY_MASK | CASE_MASK;
/** Only the 2*6 bits for the pure tertiary weight. */
static const uint32_t ONLY_TERTIARY_MASK = 0x3f3f;
/** Only the secondary & tertiary bits; no case, no quaternary. */
static const uint32_t ONLY_SEC_TER_MASK = SECONDARY_MASK | ONLY_TERTIARY_MASK;
/** Case bits and tertiary bits. */
static const uint32_t CASE_AND_TERTIARY_MASK = CASE_MASK | ONLY_TERTIARY_MASK;
static const uint32_t QUATERNARY_MASK = 0xc0;
/** Case bits and quaternary bits. */
static const uint32_t CASE_AND_QUATERNARY_MASK = CASE_MASK | QUATERNARY_MASK;
static const uint8_t UNASSIGNED_IMPLICIT_BYTE = 0xfe; // compressible
/**
* First unassigned: AlphabeticIndex overflow boundary.
* We want a 3-byte primary so that it fits into the root elements table.
*
* This 3-byte primary will not collide with
* any unassigned-implicit 4-byte primaries because
* the first few hundred Unicode code points all have real mappings.
*/
static const uint32_t FIRST_UNASSIGNED_PRIMARY = 0xfe040200;
static const uint8_t TRAIL_WEIGHT_BYTE = 0xff; // not compressible
static const uint32_t FIRST_TRAILING_PRIMARY = 0xff020200; // [first trailing]
static const uint32_t MAX_PRIMARY = 0xffff0000; // U+FFFF
static const uint32_t MAX_REGULAR_CE32 = 0xffff0505; // U+FFFF
// CE32 value for U+FFFD as well as illegal UTF-8 byte sequences (which behave like U+FFFD).
// We use the third-highest primary weight for U+FFFD (as in UCA 6.3+).
static const uint32_t FFFD_PRIMARY = MAX_PRIMARY - 0x20000;
static const uint32_t FFFD_CE32 = MAX_REGULAR_CE32 - 0x20000;
/**
* A CE32 is special if its low byte is this or greater.
* Impossible case bits 11 mark special CE32s.
* This value itself is used to indicate a fallback to the base collator.
*/
static const uint8_t SPECIAL_CE32_LOW_BYTE = 0xc0;
static const uint32_t FALLBACK_CE32 = SPECIAL_CE32_LOW_BYTE;
/**
* Low byte of a long-primary special CE32.
*/
static const uint8_t LONG_PRIMARY_CE32_LOW_BYTE = 0xc1; // SPECIAL_CE32_LOW_BYTE | LONG_PRIMARY_TAG
static const uint32_t UNASSIGNED_CE32 = 0xffffffff; // Compute an unassigned-implicit CE.
static const uint32_t NO_CE32 = 1;
/** No CE: End of input. Only used in runtime code, not stored in data. */
static const uint32_t NO_CE_PRIMARY = 1; // not a left-adjusted weight
static const uint32_t NO_CE_WEIGHT16 = 0x0100; // weight of LEVEL_SEPARATOR_BYTE
static const int64_t NO_CE = INT64_C(0x101000100); // NO_CE_PRIMARY, NO_CE_WEIGHT16, NO_CE_WEIGHT16
/** Sort key levels. */
enum Level {
/** Unspecified level. */
NO_LEVEL,
PRIMARY_LEVEL,
SECONDARY_LEVEL,
CASE_LEVEL,
TERTIARY_LEVEL,
QUATERNARY_LEVEL,
IDENTICAL_LEVEL,
/** Beyond sort key bytes. */
ZERO_LEVEL
};
/**
* Sort key level flags: xx_FLAG = 1 << xx_LEVEL.
* In Java, use enum Level with flag() getters, or use EnumSet rather than hand-made bit sets.
*/
static const uint32_t NO_LEVEL_FLAG = 1;
static const uint32_t PRIMARY_LEVEL_FLAG = 2;
static const uint32_t SECONDARY_LEVEL_FLAG = 4;
static const uint32_t CASE_LEVEL_FLAG = 8;
static const uint32_t TERTIARY_LEVEL_FLAG = 0x10;
static const uint32_t QUATERNARY_LEVEL_FLAG = 0x20;
static const uint32_t IDENTICAL_LEVEL_FLAG = 0x40;
static const uint32_t ZERO_LEVEL_FLAG = 0x80;
/**
* Special-CE32 tags, from bits 3..0 of a special 32-bit CE.
* Bits 31..8 are available for tag-specific data.
* Bits 5..4: Reserved. May be used in the future to indicate lccc!=0 and tccc!=0.
*/
enum {
/**
* Fall back to the base collator.
* This is the tag value in SPECIAL_CE32_LOW_BYTE and FALLBACK_CE32.
* Bits 31..8: Unused, 0.
*/
FALLBACK_TAG = 0,
/**
* Long-primary CE with COMMON_SEC_AND_TER_CE.
* Bits 31..8: Three-byte primary.
*/
LONG_PRIMARY_TAG = 1,
/**
* Long-secondary CE with zero primary.
* Bits 31..16: Secondary weight.
* Bits 15.. 8: Tertiary weight.
*/
LONG_SECONDARY_TAG = 2,
/**
* Unused.
* May be used in the future for single-byte secondary CEs (SHORT_SECONDARY_TAG),
* storing the secondary in bits 31..24, the ccc in bits 23..16,
* and the tertiary in bits 15..8.
*/
RESERVED_TAG_3 = 3,
/**
* Latin mini expansions of two simple CEs [pp, 05, tt] [00, ss, 05].
* Bits 31..24: Single-byte primary weight pp of the first CE.
* Bits 23..16: Tertiary weight tt of the first CE.
* Bits 15.. 8: Secondary weight ss of the second CE.
*/
LATIN_EXPANSION_TAG = 4,
/**
* Points to one or more simple/long-primary/long-secondary 32-bit CE32s.
* Bits 31..13: Index into uint32_t table.
* Bits 12.. 8: Length=1..31.
*/
EXPANSION32_TAG = 5,
/**
* Points to one or more 64-bit CEs.
* Bits 31..13: Index into CE table.
* Bits 12.. 8: Length=1..31.
*/
EXPANSION_TAG = 6,
/**
* Builder data, used only in the CollationDataBuilder, not in runtime data.
*
* If bit 8 is 0: Builder context, points to a list of context-sensitive mappings.
* Bits 31..13: Index to the builder's list of ConditionalCE32 for this character.
* Bits 12.. 9: Unused, 0.
*
* If bit 8 is 1 (IS_BUILDER_JAMO_CE32): Builder-only jamoCE32 value.
* The builder fetches the Jamo CE32 from the trie.
* Bits 31..13: Jamo code point.
* Bits 12.. 9: Unused, 0.
*/
BUILDER_DATA_TAG = 7,
/**
* Points to prefix trie.
* Bits 31..13: Index into prefix/contraction data.
* Bits 12.. 8: Unused, 0.
*/
PREFIX_TAG = 8,
/**
* Points to contraction data.
* Bits 31..13: Index into prefix/contraction data.
* Bits 12..11: Unused, 0.
* Bit 10: CONTRACT_TRAILING_CCC flag.
* Bit 9: CONTRACT_NEXT_CCC flag.
* Bit 8: CONTRACT_SINGLE_CP_NO_MATCH flag.
*/
CONTRACTION_TAG = 9,
/**
* Decimal digit.
* Bits 31..13: Index into uint32_t table for non-numeric-collation CE32.
* Bit 12: Unused, 0.
* Bits 11.. 8: Digit value 0..9.
*/
DIGIT_TAG = 10,
/**
* Tag for U+0000, for moving the NUL-termination handling
* from the regular fastpath into specials-handling code.
* Bits 31..8: Unused, 0.
*/
U0000_TAG = 11,
/**
* Tag for a Hangul syllable.
* Bits 31..9: Unused, 0.
* Bit 8: HANGUL_NO_SPECIAL_JAMO flag.
*/
HANGUL_TAG = 12,
/**
* Tag for a lead surrogate code unit.
* Optional optimization for UTF-16 string processing.
* Bits 31..10: Unused, 0.
* 9.. 8: =0: All associated supplementary code points are unassigned-implict.
* =1: All associated supplementary code points fall back to the base data.
* else: (Normally 2) Look up the data for the supplementary code point.
*/
LEAD_SURROGATE_TAG = 13,
/**
* Tag for CEs with primary weights in code point order.
* Bits 31..13: Index into CE table, for one data "CE".
* Bits 12.. 8: Unused, 0.
*
* This data "CE" has the following bit fields:
* Bits 63..32: Three-byte primary pppppp00.
* 31.. 8: Start/base code point of the in-order range.
* 7: Flag isCompressible primary.
* 6.. 0: Per-code point primary-weight increment.
*/
OFFSET_TAG = 14,
/**
* Implicit CE tag. Compute an unassigned-implicit CE.
* All bits are set (UNASSIGNED_CE32=0xffffffff).
*/
IMPLICIT_TAG = 15
};
static UBool isAssignedCE32(uint32_t ce32) {
return ce32 != FALLBACK_CE32 && ce32 != UNASSIGNED_CE32;
}
/**
* We limit the number of CEs in an expansion
* so that we can use a small number of length bits in the data structure,
* and so that an implementation can copy CEs at runtime without growing a destination buffer.
*/
static const int32_t MAX_EXPANSION_LENGTH = 31;
static const int32_t MAX_INDEX = 0x7ffff;
/**
* Set if there is no match for the single (no-suffix) character itself.
* This is only possible if there is a prefix.
* In this case, discontiguous contraction matching cannot add combining marks
* starting from an empty suffix.
* The default CE32 is used anyway if there is no suffix match.
*/
static const uint32_t CONTRACT_SINGLE_CP_NO_MATCH = 0x100;
/** Set if the first character of every contraction suffix has lccc!=0. */
static const uint32_t CONTRACT_NEXT_CCC = 0x200;
/** Set if any contraction suffix ends with lccc!=0. */
static const uint32_t CONTRACT_TRAILING_CCC = 0x400;
/** For HANGUL_TAG: None of its Jamo CE32s isSpecialCE32(). */
static const uint32_t HANGUL_NO_SPECIAL_JAMO = 0x100;
static const uint32_t LEAD_ALL_UNASSIGNED = 0;
static const uint32_t LEAD_ALL_FALLBACK = 0x100;
static const uint32_t LEAD_MIXED = 0x200;
static const uint32_t LEAD_TYPE_MASK = 0x300;
static uint32_t makeLongPrimaryCE32(uint32_t p) { return p | LONG_PRIMARY_CE32_LOW_BYTE; }
/** Turns the long-primary CE32 into a primary weight pppppp00. */
static inline uint32_t primaryFromLongPrimaryCE32(uint32_t ce32) {
return ce32 & 0xffffff00;
}
static inline int64_t ceFromLongPrimaryCE32(uint32_t ce32) {
return ((int64_t)(ce32 & 0xffffff00) << 32) | COMMON_SEC_AND_TER_CE;
}
static uint32_t makeLongSecondaryCE32(uint32_t lower32) {
return lower32 | SPECIAL_CE32_LOW_BYTE | LONG_SECONDARY_TAG;
}
static inline int64_t ceFromLongSecondaryCE32(uint32_t ce32) {
return ce32 & 0xffffff00;
}
/** Makes a special CE32 with tag, index and length. */
static uint32_t makeCE32FromTagIndexAndLength(int32_t tag, int32_t index, int32_t length) {
return (index << 13) | (length << 8) | SPECIAL_CE32_LOW_BYTE | tag;
}
/** Makes a special CE32 with only tag and index. */
static uint32_t makeCE32FromTagAndIndex(int32_t tag, int32_t index) {
return (index << 13) | SPECIAL_CE32_LOW_BYTE | tag;
}
static inline UBool isSpecialCE32(uint32_t ce32) {
return (ce32 & 0xff) >= SPECIAL_CE32_LOW_BYTE;
}
static inline int32_t tagFromCE32(uint32_t ce32) {
return (int32_t)(ce32 & 0xf);
}
static inline UBool hasCE32Tag(uint32_t ce32, int32_t tag) {
return isSpecialCE32(ce32) && tagFromCE32(ce32) == tag;
}
static inline UBool isLongPrimaryCE32(uint32_t ce32) {
return hasCE32Tag(ce32, LONG_PRIMARY_TAG);
}
static UBool isSimpleOrLongCE32(uint32_t ce32) {
return !isSpecialCE32(ce32) ||
tagFromCE32(ce32) == LONG_PRIMARY_TAG ||
tagFromCE32(ce32) == LONG_SECONDARY_TAG;
}
/**
* @return TRUE if the ce32 yields one or more CEs without further data lookups
*/
static UBool isSelfContainedCE32(uint32_t ce32) {
return !isSpecialCE32(ce32) ||
tagFromCE32(ce32) == LONG_PRIMARY_TAG ||
tagFromCE32(ce32) == LONG_SECONDARY_TAG ||
tagFromCE32(ce32) == LATIN_EXPANSION_TAG;
}
static inline UBool isPrefixCE32(uint32_t ce32) {
return hasCE32Tag(ce32, PREFIX_TAG);
}
static inline UBool isContractionCE32(uint32_t ce32) {
return hasCE32Tag(ce32, CONTRACTION_TAG);
}
static inline UBool ce32HasContext(uint32_t ce32) {
return isSpecialCE32(ce32) &&
(tagFromCE32(ce32) == PREFIX_TAG ||
tagFromCE32(ce32) == CONTRACTION_TAG);
}
/**
* Get the first of the two Latin-expansion CEs encoded in ce32.
* @see LATIN_EXPANSION_TAG
*/
static inline int64_t latinCE0FromCE32(uint32_t ce32) {
return ((int64_t)(ce32 & 0xff000000) << 32) | COMMON_SECONDARY_CE | ((ce32 & 0xff0000) >> 8);
}
/**
* Get the second of the two Latin-expansion CEs encoded in ce32.
* @see LATIN_EXPANSION_TAG
*/
static inline int64_t latinCE1FromCE32(uint32_t ce32) {
return ((ce32 & 0xff00) << 16) | COMMON_TERTIARY_CE;
}
/**
* Returns the data index from a special CE32.
*/
static inline int32_t indexFromCE32(uint32_t ce32) {
return (int32_t)(ce32 >> 13);
}
/**
* Returns the data length from a ce32.
*/
static inline int32_t lengthFromCE32(uint32_t ce32) {
return (ce32 >> 8) & 31;
}
/**
* Returns the digit value from a DIGIT_TAG ce32.
*/
static inline char digitFromCE32(uint32_t ce32) {
return (char)((ce32 >> 8) & 0xf);
}
/** Returns a 64-bit CE from a simple CE32 (not special). */
static inline int64_t ceFromSimpleCE32(uint32_t ce32) {
// normal form ppppsstt -> pppp0000ss00tt00
// assert (ce32 & 0xff) < SPECIAL_CE32_LOW_BYTE
return ((int64_t)(ce32 & 0xffff0000) << 32) | ((ce32 & 0xff00) << 16) | ((ce32 & 0xff) << 8);
}
/** Returns a 64-bit CE from a simple/long-primary/long-secondary CE32. */
static inline int64_t ceFromCE32(uint32_t ce32) {
uint32_t tertiary = ce32 & 0xff;
if(tertiary < SPECIAL_CE32_LOW_BYTE) {
// normal form ppppsstt -> pppp0000ss00tt00
return ((int64_t)(ce32 & 0xffff0000) << 32) | ((ce32 & 0xff00) << 16) | (tertiary << 8);
} else {
ce32 -= tertiary;
if((tertiary & 0xf) == LONG_PRIMARY_TAG) {
// long-primary form ppppppC1 -> pppppp00050000500
return ((int64_t)ce32 << 32) | COMMON_SEC_AND_TER_CE;
} else {
// long-secondary form ssssttC2 -> 00000000sssstt00
// assert (tertiary & 0xf) == LONG_SECONDARY_TAG
return ce32;
}
}
}
/** Creates a CE from a primary weight. */
static inline int64_t makeCE(uint32_t p) {
return ((int64_t)p << 32) | COMMON_SEC_AND_TER_CE;
}
/**
* Creates a CE from a primary weight,
* 16-bit secondary/tertiary weights, and a 2-bit quaternary.
*/
static inline int64_t makeCE(uint32_t p, uint32_t s, uint32_t t, uint32_t q) {
return ((int64_t)p << 32) | (s << 16) | t | (q << 6);
}
/**
* Increments a 2-byte primary by a code point offset.
*/
static uint32_t incTwoBytePrimaryByOffset(uint32_t basePrimary, UBool isCompressible,
int32_t offset);
/**
* Increments a 3-byte primary by a code point offset.
*/
static uint32_t incThreeBytePrimaryByOffset(uint32_t basePrimary, UBool isCompressible,
int32_t offset);
/**
* Decrements a 2-byte primary by one range step (1..0x7f).
*/
static uint32_t decTwoBytePrimaryByOneStep(uint32_t basePrimary, UBool isCompressible, int32_t step);
/**
* Decrements a 3-byte primary by one range step (1..0x7f).
*/
static uint32_t decThreeBytePrimaryByOneStep(uint32_t basePrimary, UBool isCompressible, int32_t step);
/**
* Computes a 3-byte primary for c's OFFSET_TAG data "CE".
*/
static uint32_t getThreeBytePrimaryForOffsetData(UChar32 c, int64_t dataCE);
/**
* Returns the unassigned-character implicit primary weight for any valid code point c.
*/
static uint32_t unassignedPrimaryFromCodePoint(UChar32 c);
static inline int64_t unassignedCEFromCodePoint(UChar32 c) {
return makeCE(unassignedPrimaryFromCodePoint(c));
}
private:
Collation(); // No instantiation.
};
U_NAMESPACE_END
#endif // !UCONFIG_NO_COLLATION
#endif // __COLLATION_H__