1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 *******************************************************************************
5 * Copyright (C) 2010-2015, International Business Machines
6 * Corporation and others.  All Rights Reserved.
7 *******************************************************************************
8 * collation.h
9 *
10 * created on: 2010oct27
11 * created by: Markus W. Scherer
12 */
13 
14 #ifndef __COLLATION_H__
15 #define __COLLATION_H__
16 
17 #include "unicode/utypes.h"
18 
19 #if !UCONFIG_NO_COLLATION
20 
21 U_NAMESPACE_BEGIN
22 
23 /**
24  * Collation v2 basic definitions and static helper functions.
25  *
26  * Data structures except for expansion tables store 32-bit CEs which are
27  * either specials (see tags below) or are compact forms of 64-bit CEs.
28  */
29 class U_I18N_API Collation {
30 public:
31     // Special sort key bytes for all levels.
32     static const uint8_t TERMINATOR_BYTE = 0;
33     static const uint8_t LEVEL_SEPARATOR_BYTE = 1;
34 
35     /** The secondary/tertiary lower limit for tailoring before any root elements. */
36     static const uint32_t BEFORE_WEIGHT16 = 0x0100;
37 
38     /**
39      * Merge-sort-key separator.
40      * Same as the unique primary and identical-level weights of U+FFFE.
41      * Must not be used as primary compression low terminator.
42      * Otherwise usable.
43      */
44     static const uint8_t MERGE_SEPARATOR_BYTE = 2;
45     static const uint32_t MERGE_SEPARATOR_PRIMARY = 0x02000000;  // U+FFFE
46     static const uint32_t MERGE_SEPARATOR_CE32 = 0x02000505;  // U+FFFE
47 
48     /**
49      * Primary compression low terminator, must be greater than MERGE_SEPARATOR_BYTE.
50      * Reserved value in primary second byte if the lead byte is compressible.
51      * Otherwise usable in all CE weight bytes.
52      */
53     static const uint8_t PRIMARY_COMPRESSION_LOW_BYTE = 3;
54     /**
55      * Primary compression high terminator.
56      * Reserved value in primary second byte if the lead byte is compressible.
57      * Otherwise usable in all CE weight bytes.
58      */
59     static const uint8_t PRIMARY_COMPRESSION_HIGH_BYTE = 0xff;
60 
61     /** Default secondary/tertiary weight lead byte. */
62     static const uint8_t COMMON_BYTE = 5;
63     static const uint32_t COMMON_WEIGHT16 = 0x0500;
64     /** Middle 16 bits of a CE with a common secondary weight. */
65     static const uint32_t COMMON_SECONDARY_CE = 0x05000000;
66     /** Lower 16 bits of a CE with a common tertiary weight. */
67     static const uint32_t COMMON_TERTIARY_CE = 0x0500;
68     /** Lower 32 bits of a CE with common secondary and tertiary weights. */
69     static const uint32_t COMMON_SEC_AND_TER_CE = 0x05000500;
70 
71     static const uint32_t SECONDARY_MASK = 0xffff0000;
72     static const uint32_t CASE_MASK = 0xc000;
73     static const uint32_t SECONDARY_AND_CASE_MASK = SECONDARY_MASK | CASE_MASK;
74     /** Only the 2*6 bits for the pure tertiary weight. */
75     static const uint32_t ONLY_TERTIARY_MASK = 0x3f3f;
76     /** Only the secondary & tertiary bits; no case, no quaternary. */
77     static const uint32_t ONLY_SEC_TER_MASK = SECONDARY_MASK | ONLY_TERTIARY_MASK;
78     /** Case bits and tertiary bits. */
79     static const uint32_t CASE_AND_TERTIARY_MASK = CASE_MASK | ONLY_TERTIARY_MASK;
80     static const uint32_t QUATERNARY_MASK = 0xc0;
81     /** Case bits and quaternary bits. */
82     static const uint32_t CASE_AND_QUATERNARY_MASK = CASE_MASK | QUATERNARY_MASK;
83 
84     static const uint8_t UNASSIGNED_IMPLICIT_BYTE = 0xfe;  // compressible
85     /**
86      * First unassigned: AlphabeticIndex overflow boundary.
87      * We want a 3-byte primary so that it fits into the root elements table.
88      *
89      * This 3-byte primary will not collide with
90      * any unassigned-implicit 4-byte primaries because
91      * the first few hundred Unicode code points all have real mappings.
92      */
93     static const uint32_t FIRST_UNASSIGNED_PRIMARY = 0xfe040200;
94 
95     static const uint8_t TRAIL_WEIGHT_BYTE = 0xff;  // not compressible
96     static const uint32_t FIRST_TRAILING_PRIMARY = 0xff020200;  // [first trailing]
97     static const uint32_t MAX_PRIMARY = 0xffff0000;  // U+FFFF
98     static const uint32_t MAX_REGULAR_CE32 = 0xffff0505;  // U+FFFF
99 
100     // CE32 value for U+FFFD as well as illegal UTF-8 byte sequences (which behave like U+FFFD).
101     // We use the third-highest primary weight for U+FFFD (as in UCA 6.3+).
102     static const uint32_t FFFD_PRIMARY = MAX_PRIMARY - 0x20000;
103     static const uint32_t FFFD_CE32 = MAX_REGULAR_CE32 - 0x20000;
104 
105     /**
106      * A CE32 is special if its low byte is this or greater.
107      * Impossible case bits 11 mark special CE32s.
108      * This value itself is used to indicate a fallback to the base collator.
109      */
110     static const uint8_t SPECIAL_CE32_LOW_BYTE = 0xc0;
111     static const uint32_t FALLBACK_CE32 = SPECIAL_CE32_LOW_BYTE;
112     /**
113      * Low byte of a long-primary special CE32.
114      */
115     static const uint8_t LONG_PRIMARY_CE32_LOW_BYTE = 0xc1;  // SPECIAL_CE32_LOW_BYTE | LONG_PRIMARY_TAG
116 
117     static const uint32_t UNASSIGNED_CE32 = 0xffffffff;  // Compute an unassigned-implicit CE.
118 
119     static const uint32_t NO_CE32 = 1;
120 
121     /** No CE: End of input. Only used in runtime code, not stored in data. */
122     static const uint32_t NO_CE_PRIMARY = 1;  // not a left-adjusted weight
123     static const uint32_t NO_CE_WEIGHT16 = 0x0100;  // weight of LEVEL_SEPARATOR_BYTE
124     static const int64_t NO_CE = INT64_C(0x101000100);  // NO_CE_PRIMARY, NO_CE_WEIGHT16, NO_CE_WEIGHT16
125 
126     /** Sort key levels. */
127     enum Level {
128         /** Unspecified level. */
129         NO_LEVEL,
130         PRIMARY_LEVEL,
131         SECONDARY_LEVEL,
132         CASE_LEVEL,
133         TERTIARY_LEVEL,
134         QUATERNARY_LEVEL,
135         IDENTICAL_LEVEL,
136         /** Beyond sort key bytes. */
137         ZERO_LEVEL
138     };
139 
140     /**
141      * Sort key level flags: xx_FLAG = 1 << xx_LEVEL.
142      * In Java, use enum Level with flag() getters, or use EnumSet rather than hand-made bit sets.
143      */
144     static const uint32_t NO_LEVEL_FLAG = 1;
145     static const uint32_t PRIMARY_LEVEL_FLAG = 2;
146     static const uint32_t SECONDARY_LEVEL_FLAG = 4;
147     static const uint32_t CASE_LEVEL_FLAG = 8;
148     static const uint32_t TERTIARY_LEVEL_FLAG = 0x10;
149     static const uint32_t QUATERNARY_LEVEL_FLAG = 0x20;
150     static const uint32_t IDENTICAL_LEVEL_FLAG = 0x40;
151     static const uint32_t ZERO_LEVEL_FLAG = 0x80;
152 
153     /**
154      * Special-CE32 tags, from bits 3..0 of a special 32-bit CE.
155      * Bits 31..8 are available for tag-specific data.
156      * Bits  5..4: Reserved. May be used in the future to indicate lccc!=0 and tccc!=0.
157      */
158     enum {
159         /**
160          * Fall back to the base collator.
161          * This is the tag value in SPECIAL_CE32_LOW_BYTE and FALLBACK_CE32.
162          * Bits 31..8: Unused, 0.
163          */
164         FALLBACK_TAG = 0,
165         /**
166          * Long-primary CE with COMMON_SEC_AND_TER_CE.
167          * Bits 31..8: Three-byte primary.
168          */
169         LONG_PRIMARY_TAG = 1,
170         /**
171          * Long-secondary CE with zero primary.
172          * Bits 31..16: Secondary weight.
173          * Bits 15.. 8: Tertiary weight.
174          */
175         LONG_SECONDARY_TAG = 2,
176         /**
177          * Unused.
178          * May be used in the future for single-byte secondary CEs (SHORT_SECONDARY_TAG),
179          * storing the secondary in bits 31..24, the ccc in bits 23..16,
180          * and the tertiary in bits 15..8.
181          */
182         RESERVED_TAG_3 = 3,
183         /**
184          * Latin mini expansions of two simple CEs [pp, 05, tt] [00, ss, 05].
185          * Bits 31..24: Single-byte primary weight pp of the first CE.
186          * Bits 23..16: Tertiary weight tt of the first CE.
187          * Bits 15.. 8: Secondary weight ss of the second CE.
188          */
189         LATIN_EXPANSION_TAG = 4,
190         /**
191          * Points to one or more simple/long-primary/long-secondary 32-bit CE32s.
192          * Bits 31..13: Index into uint32_t table.
193          * Bits 12.. 8: Length=1..31.
194          */
195         EXPANSION32_TAG = 5,
196         /**
197          * Points to one or more 64-bit CEs.
198          * Bits 31..13: Index into CE table.
199          * Bits 12.. 8: Length=1..31.
200          */
201         EXPANSION_TAG = 6,
202         /**
203          * Builder data, used only in the CollationDataBuilder, not in runtime data.
204          *
205          * If bit 8 is 0: Builder context, points to a list of context-sensitive mappings.
206          * Bits 31..13: Index to the builder's list of ConditionalCE32 for this character.
207          * Bits 12.. 9: Unused, 0.
208          *
209          * If bit 8 is 1 (IS_BUILDER_JAMO_CE32): Builder-only jamoCE32 value.
210          * The builder fetches the Jamo CE32 from the trie.
211          * Bits 31..13: Jamo code point.
212          * Bits 12.. 9: Unused, 0.
213          */
214         BUILDER_DATA_TAG = 7,
215         /**
216          * Points to prefix trie.
217          * Bits 31..13: Index into prefix/contraction data.
218          * Bits 12.. 8: Unused, 0.
219          */
220         PREFIX_TAG = 8,
221         /**
222          * Points to contraction data.
223          * Bits 31..13: Index into prefix/contraction data.
224          * Bits 12..11: Unused, 0.
225          * Bit      10: CONTRACT_TRAILING_CCC flag.
226          * Bit       9: CONTRACT_NEXT_CCC flag.
227          * Bit       8: CONTRACT_SINGLE_CP_NO_MATCH flag.
228          */
229         CONTRACTION_TAG = 9,
230         /**
231          * Decimal digit.
232          * Bits 31..13: Index into uint32_t table for non-numeric-collation CE32.
233          * Bit      12: Unused, 0.
234          * Bits 11.. 8: Digit value 0..9.
235          */
236         DIGIT_TAG = 10,
237         /**
238          * Tag for U+0000, for moving the NUL-termination handling
239          * from the regular fastpath into specials-handling code.
240          * Bits 31..8: Unused, 0.
241          */
242         U0000_TAG = 11,
243         /**
244          * Tag for a Hangul syllable.
245          * Bits 31..9: Unused, 0.
246          * Bit      8: HANGUL_NO_SPECIAL_JAMO flag.
247          */
248         HANGUL_TAG = 12,
249         /**
250          * Tag for a lead surrogate code unit.
251          * Optional optimization for UTF-16 string processing.
252          * Bits 31..10: Unused, 0.
253          *       9.. 8: =0: All associated supplementary code points are unassigned-implict.
254          *              =1: All associated supplementary code points fall back to the base data.
255          *              else: (Normally 2) Look up the data for the supplementary code point.
256          */
257         LEAD_SURROGATE_TAG = 13,
258         /**
259          * Tag for CEs with primary weights in code point order.
260          * Bits 31..13: Index into CE table, for one data "CE".
261          * Bits 12.. 8: Unused, 0.
262          *
263          * This data "CE" has the following bit fields:
264          * Bits 63..32: Three-byte primary pppppp00.
265          *      31.. 8: Start/base code point of the in-order range.
266          *           7: Flag isCompressible primary.
267          *       6.. 0: Per-code point primary-weight increment.
268          */
269         OFFSET_TAG = 14,
270         /**
271          * Implicit CE tag. Compute an unassigned-implicit CE.
272          * All bits are set (UNASSIGNED_CE32=0xffffffff).
273          */
274         IMPLICIT_TAG = 15
275     };
276 
isAssignedCE32(uint32_t ce32)277     static UBool isAssignedCE32(uint32_t ce32) {
278         return ce32 != FALLBACK_CE32 && ce32 != UNASSIGNED_CE32;
279     }
280 
281     /**
282      * We limit the number of CEs in an expansion
283      * so that we can use a small number of length bits in the data structure,
284      * and so that an implementation can copy CEs at runtime without growing a destination buffer.
285      */
286     static const int32_t MAX_EXPANSION_LENGTH = 31;
287     static const int32_t MAX_INDEX = 0x7ffff;
288 
289     /**
290      * Set if there is no match for the single (no-suffix) character itself.
291      * This is only possible if there is a prefix.
292      * In this case, discontiguous contraction matching cannot add combining marks
293      * starting from an empty suffix.
294      * The default CE32 is used anyway if there is no suffix match.
295      */
296     static const uint32_t CONTRACT_SINGLE_CP_NO_MATCH = 0x100;
297     /** Set if the first character of every contraction suffix has lccc!=0. */
298     static const uint32_t CONTRACT_NEXT_CCC = 0x200;
299     /** Set if any contraction suffix ends with lccc!=0. */
300     static const uint32_t CONTRACT_TRAILING_CCC = 0x400;
301 
302     /** For HANGUL_TAG: None of its Jamo CE32s isSpecialCE32(). */
303     static const uint32_t HANGUL_NO_SPECIAL_JAMO = 0x100;
304 
305     static const uint32_t LEAD_ALL_UNASSIGNED = 0;
306     static const uint32_t LEAD_ALL_FALLBACK = 0x100;
307     static const uint32_t LEAD_MIXED = 0x200;
308     static const uint32_t LEAD_TYPE_MASK = 0x300;
309 
makeLongPrimaryCE32(uint32_t p)310     static uint32_t makeLongPrimaryCE32(uint32_t p) { return p | LONG_PRIMARY_CE32_LOW_BYTE; }
311 
312     /** Turns the long-primary CE32 into a primary weight pppppp00. */
primaryFromLongPrimaryCE32(uint32_t ce32)313     static inline uint32_t primaryFromLongPrimaryCE32(uint32_t ce32) {
314         return ce32 & 0xffffff00;
315     }
ceFromLongPrimaryCE32(uint32_t ce32)316     static inline int64_t ceFromLongPrimaryCE32(uint32_t ce32) {
317         return ((int64_t)(ce32 & 0xffffff00) << 32) | COMMON_SEC_AND_TER_CE;
318     }
319 
makeLongSecondaryCE32(uint32_t lower32)320     static uint32_t makeLongSecondaryCE32(uint32_t lower32) {
321         return lower32 | SPECIAL_CE32_LOW_BYTE | LONG_SECONDARY_TAG;
322     }
ceFromLongSecondaryCE32(uint32_t ce32)323     static inline int64_t ceFromLongSecondaryCE32(uint32_t ce32) {
324         return ce32 & 0xffffff00;
325     }
326 
327     /** Makes a special CE32 with tag, index and length. */
makeCE32FromTagIndexAndLength(int32_t tag,int32_t index,int32_t length)328     static uint32_t makeCE32FromTagIndexAndLength(int32_t tag, int32_t index, int32_t length) {
329         return (index << 13) | (length << 8) | SPECIAL_CE32_LOW_BYTE | tag;
330     }
331     /** Makes a special CE32 with only tag and index. */
makeCE32FromTagAndIndex(int32_t tag,int32_t index)332     static uint32_t makeCE32FromTagAndIndex(int32_t tag, int32_t index) {
333         return (index << 13) | SPECIAL_CE32_LOW_BYTE | tag;
334     }
335 
isSpecialCE32(uint32_t ce32)336     static inline UBool isSpecialCE32(uint32_t ce32) {
337         return (ce32 & 0xff) >= SPECIAL_CE32_LOW_BYTE;
338     }
339 
tagFromCE32(uint32_t ce32)340     static inline int32_t tagFromCE32(uint32_t ce32) {
341         return (int32_t)(ce32 & 0xf);
342     }
343 
hasCE32Tag(uint32_t ce32,int32_t tag)344     static inline UBool hasCE32Tag(uint32_t ce32, int32_t tag) {
345         return isSpecialCE32(ce32) && tagFromCE32(ce32) == tag;
346     }
347 
isLongPrimaryCE32(uint32_t ce32)348     static inline UBool isLongPrimaryCE32(uint32_t ce32) {
349         return hasCE32Tag(ce32, LONG_PRIMARY_TAG);
350     }
351 
isSimpleOrLongCE32(uint32_t ce32)352     static UBool isSimpleOrLongCE32(uint32_t ce32) {
353         return !isSpecialCE32(ce32) ||
354                 tagFromCE32(ce32) == LONG_PRIMARY_TAG ||
355                 tagFromCE32(ce32) == LONG_SECONDARY_TAG;
356     }
357 
358     /**
359      * @return TRUE if the ce32 yields one or more CEs without further data lookups
360      */
isSelfContainedCE32(uint32_t ce32)361     static UBool isSelfContainedCE32(uint32_t ce32) {
362         return !isSpecialCE32(ce32) ||
363                 tagFromCE32(ce32) == LONG_PRIMARY_TAG ||
364                 tagFromCE32(ce32) == LONG_SECONDARY_TAG ||
365                 tagFromCE32(ce32) == LATIN_EXPANSION_TAG;
366     }
367 
isPrefixCE32(uint32_t ce32)368     static inline UBool isPrefixCE32(uint32_t ce32) {
369         return hasCE32Tag(ce32, PREFIX_TAG);
370     }
371 
isContractionCE32(uint32_t ce32)372     static inline UBool isContractionCE32(uint32_t ce32) {
373         return hasCE32Tag(ce32, CONTRACTION_TAG);
374     }
375 
ce32HasContext(uint32_t ce32)376     static inline UBool ce32HasContext(uint32_t ce32) {
377         return isSpecialCE32(ce32) &&
378                 (tagFromCE32(ce32) == PREFIX_TAG ||
379                 tagFromCE32(ce32) == CONTRACTION_TAG);
380     }
381 
382     /**
383      * Get the first of the two Latin-expansion CEs encoded in ce32.
384      * @see LATIN_EXPANSION_TAG
385      */
latinCE0FromCE32(uint32_t ce32)386     static inline int64_t latinCE0FromCE32(uint32_t ce32) {
387         return ((int64_t)(ce32 & 0xff000000) << 32) | COMMON_SECONDARY_CE | ((ce32 & 0xff0000) >> 8);
388     }
389 
390     /**
391      * Get the second of the two Latin-expansion CEs encoded in ce32.
392      * @see LATIN_EXPANSION_TAG
393      */
latinCE1FromCE32(uint32_t ce32)394     static inline int64_t latinCE1FromCE32(uint32_t ce32) {
395         return ((ce32 & 0xff00) << 16) | COMMON_TERTIARY_CE;
396     }
397 
398     /**
399      * Returns the data index from a special CE32.
400      */
indexFromCE32(uint32_t ce32)401     static inline int32_t indexFromCE32(uint32_t ce32) {
402         return (int32_t)(ce32 >> 13);
403     }
404 
405     /**
406      * Returns the data length from a ce32.
407      */
lengthFromCE32(uint32_t ce32)408     static inline int32_t lengthFromCE32(uint32_t ce32) {
409         return (ce32 >> 8) & 31;
410     }
411 
412     /**
413      * Returns the digit value from a DIGIT_TAG ce32.
414      */
digitFromCE32(uint32_t ce32)415     static inline char digitFromCE32(uint32_t ce32) {
416         return (char)((ce32 >> 8) & 0xf);
417     }
418 
419     /** Returns a 64-bit CE from a simple CE32 (not special). */
ceFromSimpleCE32(uint32_t ce32)420     static inline int64_t ceFromSimpleCE32(uint32_t ce32) {
421         // normal form ppppsstt -> pppp0000ss00tt00
422         // assert (ce32 & 0xff) < SPECIAL_CE32_LOW_BYTE
423         return ((int64_t)(ce32 & 0xffff0000) << 32) | ((ce32 & 0xff00) << 16) | ((ce32 & 0xff) << 8);
424     }
425 
426     /** Returns a 64-bit CE from a simple/long-primary/long-secondary CE32. */
ceFromCE32(uint32_t ce32)427     static inline int64_t ceFromCE32(uint32_t ce32) {
428         uint32_t tertiary = ce32 & 0xff;
429         if(tertiary < SPECIAL_CE32_LOW_BYTE) {
430             // normal form ppppsstt -> pppp0000ss00tt00
431             return ((int64_t)(ce32 & 0xffff0000) << 32) | ((ce32 & 0xff00) << 16) | (tertiary << 8);
432         } else {
433             ce32 -= tertiary;
434             if((tertiary & 0xf) == LONG_PRIMARY_TAG) {
435                 // long-primary form ppppppC1 -> pppppp00050000500
436                 return ((int64_t)ce32 << 32) | COMMON_SEC_AND_TER_CE;
437             } else {
438                 // long-secondary form ssssttC2 -> 00000000sssstt00
439                 // assert (tertiary & 0xf) == LONG_SECONDARY_TAG
440                 return ce32;
441             }
442         }
443     }
444 
445     /** Creates a CE from a primary weight. */
makeCE(uint32_t p)446     static inline int64_t makeCE(uint32_t p) {
447         return ((int64_t)p << 32) | COMMON_SEC_AND_TER_CE;
448     }
449     /**
450      * Creates a CE from a primary weight,
451      * 16-bit secondary/tertiary weights, and a 2-bit quaternary.
452      */
makeCE(uint32_t p,uint32_t s,uint32_t t,uint32_t q)453     static inline int64_t makeCE(uint32_t p, uint32_t s, uint32_t t, uint32_t q) {
454         return ((int64_t)p << 32) | (s << 16) | t | (q << 6);
455     }
456 
457     /**
458      * Increments a 2-byte primary by a code point offset.
459      */
460     static uint32_t incTwoBytePrimaryByOffset(uint32_t basePrimary, UBool isCompressible,
461                                               int32_t offset);
462 
463     /**
464      * Increments a 3-byte primary by a code point offset.
465      */
466     static uint32_t incThreeBytePrimaryByOffset(uint32_t basePrimary, UBool isCompressible,
467                                                 int32_t offset);
468 
469     /**
470      * Decrements a 2-byte primary by one range step (1..0x7f).
471      */
472     static uint32_t decTwoBytePrimaryByOneStep(uint32_t basePrimary, UBool isCompressible, int32_t step);
473 
474     /**
475      * Decrements a 3-byte primary by one range step (1..0x7f).
476      */
477     static uint32_t decThreeBytePrimaryByOneStep(uint32_t basePrimary, UBool isCompressible, int32_t step);
478 
479     /**
480      * Computes a 3-byte primary for c's OFFSET_TAG data "CE".
481      */
482     static uint32_t getThreeBytePrimaryForOffsetData(UChar32 c, int64_t dataCE);
483 
484     /**
485      * Returns the unassigned-character implicit primary weight for any valid code point c.
486      */
487     static uint32_t unassignedPrimaryFromCodePoint(UChar32 c);
488 
unassignedCEFromCodePoint(UChar32 c)489     static inline int64_t unassignedCEFromCodePoint(UChar32 c) {
490         return makeCE(unassignedPrimaryFromCodePoint(c));
491     }
492 
493 private:
494     Collation();  // No instantiation.
495 };
496 
497 U_NAMESPACE_END
498 
499 #endif  // !UCONFIG_NO_COLLATION
500 #endif  // __COLLATION_H__
501