aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/icu/common/ucasemap.cpp
blob: ed72bda828fc1c85fe114c56bb6b2761f08abd83 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
*
*   Copyright (C) 2005-2016, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
*******************************************************************************
*   file name:  ucasemap.cpp
*   encoding:   UTF-8
*   tab size:   8 (not used)
*   indentation:4
*
*   created on: 2005may06
*   created by: Markus W. Scherer
*
*   Case mapping service object and functions using it.
*/

#include "unicode/utypes.h"
#include "unicode/brkiter.h"
#include "unicode/bytestream.h"
#include "unicode/casemap.h"
#include "unicode/edits.h"
#include "unicode/stringoptions.h"
#include "unicode/stringpiece.h"
#include "unicode/ubrk.h"
#include "unicode/uloc.h"
#include "unicode/ustring.h"
#include "unicode/ucasemap.h"
#if !UCONFIG_NO_BREAK_ITERATION
#include "unicode/utext.h"
#endif
#include "unicode/utf.h"
#include "unicode/utf8.h"
#include "unicode/utf16.h"
#include "bytesinkutil.h"
#include "cmemory.h"
#include "cstring.h"
#include "uassert.h"
#include "ucase.h"
#include "ucasemap_imp.h"
#include "ustr_imp.h"

U_NAMESPACE_USE

/* UCaseMap service object -------------------------------------------------- */

UCaseMap::UCaseMap(const char *localeID, uint32_t opts, UErrorCode *pErrorCode) :
#if !UCONFIG_NO_BREAK_ITERATION
        iter(NULL),
#endif
        caseLocale(UCASE_LOC_UNKNOWN), options(opts) {
    ucasemap_setLocale(this, localeID, pErrorCode);
}

UCaseMap::~UCaseMap() {
#if !UCONFIG_NO_BREAK_ITERATION
    delete iter;
#endif
}

U_CAPI UCaseMap * U_EXPORT2
ucasemap_open(const char *locale, uint32_t options, UErrorCode *pErrorCode) {
    if(U_FAILURE(*pErrorCode)) {
        return NULL;
    }
    UCaseMap *csm = new UCaseMap(locale, options, pErrorCode);
    if(csm==NULL) {
        *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
        return NULL;
    } else if (U_FAILURE(*pErrorCode)) {
        delete csm;
        return NULL;
    }
    return csm;
}

U_CAPI void U_EXPORT2
ucasemap_close(UCaseMap *csm) {
    delete csm;
}

U_CAPI const char * U_EXPORT2
ucasemap_getLocale(const UCaseMap *csm) {
    return csm->locale;
}

U_CAPI uint32_t U_EXPORT2
ucasemap_getOptions(const UCaseMap *csm) {
    return csm->options;
}

U_CAPI void U_EXPORT2
ucasemap_setLocale(UCaseMap *csm, const char *locale, UErrorCode *pErrorCode) {
    if(U_FAILURE(*pErrorCode)) {
        return;
    }
    if (locale != NULL && *locale == 0) {
        csm->locale[0] = 0;
        csm->caseLocale = UCASE_LOC_ROOT;
        return;
    }

    int32_t length=uloc_getName(locale, csm->locale, (int32_t)sizeof(csm->locale), pErrorCode);
    if(*pErrorCode==U_BUFFER_OVERFLOW_ERROR || length==sizeof(csm->locale)) {
        *pErrorCode=U_ZERO_ERROR;
        /* we only really need the language code for case mappings */
        length=uloc_getLanguage(locale, csm->locale, (int32_t)sizeof(csm->locale), pErrorCode);
    }
    if(length==sizeof(csm->locale)) {
        *pErrorCode=U_BUFFER_OVERFLOW_ERROR;
    }
    if(U_SUCCESS(*pErrorCode)) {
        csm->caseLocale=UCASE_LOC_UNKNOWN;
        csm->caseLocale = ucase_getCaseLocale(csm->locale);
    } else {
        csm->locale[0]=0;
        csm->caseLocale = UCASE_LOC_ROOT;
    }
}

U_CAPI void U_EXPORT2
ucasemap_setOptions(UCaseMap *csm, uint32_t options, UErrorCode *pErrorCode) {
    if(U_FAILURE(*pErrorCode)) {
        return;
    }
    csm->options=options;
}

/* UTF-8 string case mappings ----------------------------------------------- */

/* TODO(markus): Move to a new, separate utf8case.cpp file. */

namespace {

/* append a full case mapping result, see UCASE_MAX_STRING_LENGTH */
inline UBool
appendResult(int32_t cpLength, int32_t result, const UChar *s,
             ByteSink &sink, uint32_t options, icu::Edits *edits, UErrorCode &errorCode) {
    U_ASSERT(U_SUCCESS(errorCode));

    /* decode the result */
    if(result<0) {
        /* (not) original code point */
        if(edits!=NULL) {
            edits->addUnchanged(cpLength);
        }
        if((options & U_OMIT_UNCHANGED_TEXT) == 0) {
            ByteSinkUtil::appendCodePoint(cpLength, ~result, sink);
        }
    } else {
        if(result<=UCASE_MAX_STRING_LENGTH) {
            // string: "result" is the UTF-16 length
            return ByteSinkUtil::appendChange(cpLength, s, result, sink, edits, errorCode);
        } else {
            ByteSinkUtil::appendCodePoint(cpLength, result, sink, edits);
        }
    }
    return TRUE;
}

// See unicode/utf8.h U8_APPEND_UNSAFE().
inline uint8_t getTwoByteLead(UChar32 c) { return (uint8_t)((c >> 6) | 0xc0); }
inline uint8_t getTwoByteTrail(UChar32 c) { return (uint8_t)((c & 0x3f) | 0x80); }

UChar32 U_CALLCONV
utf8_caseContextIterator(void *context, int8_t dir) {
    UCaseContext *csc=(UCaseContext *)context;
    UChar32 c;

    if(dir<0) {
        /* reset for backward iteration */
        csc->index=csc->cpStart;
        csc->dir=dir;
    } else if(dir>0) {
        /* reset for forward iteration */
        csc->index=csc->cpLimit;
        csc->dir=dir;
    } else {
        /* continue current iteration direction */
        dir=csc->dir;
    }

    if(dir<0) {
        if(csc->start<csc->index) {
            U8_PREV((const uint8_t *)csc->p, csc->start, csc->index, c);
            return c;
        }
    } else {
        if(csc->index<csc->limit) {
            U8_NEXT((const uint8_t *)csc->p, csc->index, csc->limit, c);
            return c;
        }
    }
    return U_SENTINEL;
}

/**
 * caseLocale >= 0: Lowercases [srcStart..srcLimit[ but takes context [0..srcLength[ into account.
 * caseLocale < 0: Case-folds [srcStart..srcLimit[.
 */
void toLower(int32_t caseLocale, uint32_t options,
             const uint8_t *src, UCaseContext *csc, int32_t srcStart, int32_t srcLimit,
             icu::ByteSink &sink, icu::Edits *edits, UErrorCode &errorCode) {
    const int8_t *latinToLower;
    if (caseLocale == UCASE_LOC_ROOT ||
            (caseLocale >= 0 ?
                !(caseLocale == UCASE_LOC_TURKISH || caseLocale == UCASE_LOC_LITHUANIAN) :
                (options & _FOLD_CASE_OPTIONS_MASK) == U_FOLD_CASE_DEFAULT)) {
        latinToLower = LatinCase::TO_LOWER_NORMAL;
    } else {
        latinToLower = LatinCase::TO_LOWER_TR_LT;
    }
    const UTrie2 *trie = ucase_getTrie();
    int32_t prev = srcStart;
    int32_t srcIndex = srcStart;
    for (;;) {
        // fast path for simple cases
        int32_t cpStart;
        UChar32 c;
        for (;;) {
            if (U_FAILURE(errorCode) || srcIndex >= srcLimit) {
                c = U_SENTINEL;
                break;
            }
            uint8_t lead = src[srcIndex++];
            if (lead <= 0x7f) {
                int8_t d = latinToLower[lead];
                if (d == LatinCase::EXC) {
                    cpStart = srcIndex - 1;
                    c = lead;
                    break;
                }
                if (d == 0) { continue; }
                ByteSinkUtil::appendUnchanged(src + prev, srcIndex - 1 - prev,
                                              sink, options, edits, errorCode);
                char ascii = (char)(lead + d);
                sink.Append(&ascii, 1);
                if (edits != nullptr) {
                    edits->addReplace(1, 1);
                }
                prev = srcIndex;
                continue;
            } else if (lead < 0xe3) {
                uint8_t t;
                if (0xc2 <= lead && lead <= 0xc5 && srcIndex < srcLimit &&
                        (t = src[srcIndex] - 0x80) <= 0x3f) {
                    // U+0080..U+017F
                    ++srcIndex;
                    c = ((lead - 0xc0) << 6) | t;
                    int8_t d = latinToLower[c];
                    if (d == LatinCase::EXC) {
                        cpStart = srcIndex - 2;
                        break;
                    }
                    if (d == 0) { continue; }
                    ByteSinkUtil::appendUnchanged(src + prev, srcIndex - 2 - prev,
                                                  sink, options, edits, errorCode);
                    ByteSinkUtil::appendTwoBytes(c + d, sink);
                    if (edits != nullptr) {
                        edits->addReplace(2, 2);
                    }
                    prev = srcIndex;
                    continue;
                }
            } else if ((lead <= 0xe9 || lead == 0xeb || lead == 0xec) &&
                    (srcIndex + 2) <= srcLimit &&
                    U8_IS_TRAIL(src[srcIndex]) && U8_IS_TRAIL(src[srcIndex + 1])) {
                // most of CJK: no case mappings
                srcIndex += 2;
                continue;
            }
            cpStart = --srcIndex;
            U8_NEXT(src, srcIndex, srcLimit, c);
            if (c < 0) {
                // ill-formed UTF-8
                continue;
            }
            uint16_t props = UTRIE2_GET16(trie, c);
            if (UCASE_HAS_EXCEPTION(props)) { break; }
            int32_t delta;
            if (!UCASE_IS_UPPER_OR_TITLE(props) || (delta = UCASE_GET_DELTA(props)) == 0) {
                continue;
            }
            ByteSinkUtil::appendUnchanged(src + prev, cpStart - prev,
                                          sink, options, edits, errorCode);
            ByteSinkUtil::appendCodePoint(srcIndex - cpStart, c + delta, sink, edits);
            prev = srcIndex;
        }
        if (c < 0) {
            break;
        }
        // slow path
        const UChar *s;
        if (caseLocale >= 0) {
            csc->cpStart = cpStart;
            csc->cpLimit = srcIndex;
            c = ucase_toFullLower(c, utf8_caseContextIterator, csc, &s, caseLocale);
        } else {
            c = ucase_toFullFolding(c, &s, options);
        }
        if (c >= 0) {
            ByteSinkUtil::appendUnchanged(src + prev, cpStart - prev,
                                          sink, options, edits, errorCode);
            appendResult(srcIndex - cpStart, c, s, sink, options, edits, errorCode);
            prev = srcIndex;
        }
    }
    ByteSinkUtil::appendUnchanged(src + prev, srcIndex - prev,
                                  sink, options, edits, errorCode);
}

void toUpper(int32_t caseLocale, uint32_t options,
             const uint8_t *src, UCaseContext *csc, int32_t srcLength,
             icu::ByteSink &sink, icu::Edits *edits, UErrorCode &errorCode) {
    const int8_t *latinToUpper;
    if (caseLocale == UCASE_LOC_TURKISH) {
        latinToUpper = LatinCase::TO_UPPER_TR;
    } else {
        latinToUpper = LatinCase::TO_UPPER_NORMAL;
    }
    const UTrie2 *trie = ucase_getTrie();
    int32_t prev = 0;
    int32_t srcIndex = 0;
    for (;;) {
        // fast path for simple cases
        int32_t cpStart;
        UChar32 c;
        for (;;) {
            if (U_FAILURE(errorCode) || srcIndex >= srcLength) {
                c = U_SENTINEL;
                break;
            }
            uint8_t lead = src[srcIndex++];
            if (lead <= 0x7f) {
                int8_t d = latinToUpper[lead];
                if (d == LatinCase::EXC) {
                    cpStart = srcIndex - 1;
                    c = lead;
                    break;
                }
                if (d == 0) { continue; }
                ByteSinkUtil::appendUnchanged(src + prev, srcIndex - 1 - prev,
                                              sink, options, edits, errorCode);
                char ascii = (char)(lead + d);
                sink.Append(&ascii, 1);
                if (edits != nullptr) {
                    edits->addReplace(1, 1);
                }
                prev = srcIndex;
                continue;
            } else if (lead < 0xe3) {
                uint8_t t;
                if (0xc2 <= lead && lead <= 0xc5 && srcIndex < srcLength &&
                        (t = src[srcIndex] - 0x80) <= 0x3f) {
                    // U+0080..U+017F
                    ++srcIndex;
                    c = ((lead - 0xc0) << 6) | t;
                    int8_t d = latinToUpper[c];
                    if (d == LatinCase::EXC) {
                        cpStart = srcIndex - 2;
                        break;
                    }
                    if (d == 0) { continue; }
                    ByteSinkUtil::appendUnchanged(src + prev, srcIndex - 2 - prev,
                                                  sink, options, edits, errorCode);
                    ByteSinkUtil::appendTwoBytes(c + d, sink);
                    if (edits != nullptr) {
                        edits->addReplace(2, 2);
                    }
                    prev = srcIndex;
                    continue;
                }
            } else if ((lead <= 0xe9 || lead == 0xeb || lead == 0xec) &&
                    (srcIndex + 2) <= srcLength &&
                    U8_IS_TRAIL(src[srcIndex]) && U8_IS_TRAIL(src[srcIndex + 1])) {
                // most of CJK: no case mappings
                srcIndex += 2;
                continue;
            }
            cpStart = --srcIndex;
            U8_NEXT(src, srcIndex, srcLength, c);
            if (c < 0) {
                // ill-formed UTF-8
                continue;
            }
            uint16_t props = UTRIE2_GET16(trie, c);
            if (UCASE_HAS_EXCEPTION(props)) { break; }
            int32_t delta;
            if (UCASE_GET_TYPE(props) != UCASE_LOWER || (delta = UCASE_GET_DELTA(props)) == 0) {
                continue;
            }
            ByteSinkUtil::appendUnchanged(src + prev, cpStart - prev,
                                          sink, options, edits, errorCode);
            ByteSinkUtil::appendCodePoint(srcIndex - cpStart, c + delta, sink, edits);
            prev = srcIndex;
        }
        if (c < 0) {
            break;
        }
        // slow path
        csc->cpStart = cpStart;
        csc->cpLimit = srcIndex;
        const UChar *s;
        c = ucase_toFullUpper(c, utf8_caseContextIterator, csc, &s, caseLocale);
        if (c >= 0) {
            ByteSinkUtil::appendUnchanged(src + prev, cpStart - prev,
                                          sink, options, edits, errorCode);
            appendResult(srcIndex - cpStart, c, s, sink, options, edits, errorCode);
            prev = srcIndex;
        }
    }
    ByteSinkUtil::appendUnchanged(src + prev, srcIndex - prev,
                                  sink, options, edits, errorCode);
}

}  // namespace

#if !UCONFIG_NO_BREAK_ITERATION

U_CFUNC void U_CALLCONV
ucasemap_internalUTF8ToTitle(
        int32_t caseLocale, uint32_t options, BreakIterator *iter,
        const uint8_t *src, int32_t srcLength,
        ByteSink &sink, icu::Edits *edits,
        UErrorCode &errorCode) {
    if (!ustrcase_checkTitleAdjustmentOptions(options, errorCode)) {
        return;
    }

    /* set up local variables */
    UCaseContext csc=UCASECONTEXT_INITIALIZER;
    csc.p=(void *)src;
    csc.limit=srcLength;
    int32_t prev=0;
    UBool isFirstIndex=TRUE;

    /* titlecasing loop */
    while(prev<srcLength) {
        /* find next index where to titlecase */
        int32_t index;
        if(isFirstIndex) {
            isFirstIndex=FALSE;
            index=iter->first();
        } else {
            index=iter->next();
        }
        if(index==UBRK_DONE || index>srcLength) {
            index=srcLength;
        }

        /*
         * Segment [prev..index[ into 3 parts:
         * a) skipped characters (copy as-is) [prev..titleStart[
         * b) first letter (titlecase)              [titleStart..titleLimit[
         * c) subsequent characters (lowercase)                 [titleLimit..index[
         */
        if(prev<index) {
            /* find and copy skipped characters [prev..titleStart[ */
            int32_t titleStart=prev;
            int32_t titleLimit=prev;
            UChar32 c;
            U8_NEXT(src, titleLimit, index, c);
            if ((options&U_TITLECASE_NO_BREAK_ADJUSTMENT)==0) {
                // Adjust the titlecasing index to the next cased character,
                // or to the next letter/number/symbol/private use.
                // Stop with titleStart<titleLimit<=index
                // if there is a character to be titlecased,
                // or else stop with titleStart==titleLimit==index.
                UBool toCased = (options&U_TITLECASE_ADJUST_TO_CASED) != 0;
                while (toCased ? UCASE_NONE==ucase_getType(c) : !ustrcase_isLNS(c)) {
                    titleStart=titleLimit;
                    if(titleLimit==index) {
                        break;
                    }
                    U8_NEXT(src, titleLimit, index, c);
                }
                if (prev < titleStart) {
                    if (!ByteSinkUtil::appendUnchanged(src+prev, titleStart-prev,
                                                       sink, options, edits, errorCode)) {
                        return;
                    }
                }
            }

            if(titleStart<titleLimit) {
                /* titlecase c which is from [titleStart..titleLimit[ */
                if(c>=0) {
                    csc.cpStart=titleStart;
                    csc.cpLimit=titleLimit;
                    const UChar *s;
                    c=ucase_toFullTitle(c, utf8_caseContextIterator, &csc, &s, caseLocale);
                    if (!appendResult(titleLimit-titleStart, c, s, sink, options, edits, errorCode)) {
                        return;
                    }
                } else {
                    // Malformed UTF-8.
                    if (!ByteSinkUtil::appendUnchanged(src+titleStart, titleLimit-titleStart,
                                                       sink, options, edits, errorCode)) {
                        return;
                    }
                }

                /* Special case Dutch IJ titlecasing */
                if (titleStart+1 < index &&
                        caseLocale == UCASE_LOC_DUTCH &&
                        (src[titleStart] == 0x0049 || src[titleStart] == 0x0069)) {
                    if (src[titleStart+1] == 0x006A) {
                        ByteSinkUtil::appendCodePoint(1, 0x004A, sink, edits);
                        titleLimit++;
                    } else if (src[titleStart+1] == 0x004A) {
                        // Keep the capital J from getting lowercased.
                        if (!ByteSinkUtil::appendUnchanged(src+titleStart+1, 1,
                                                           sink, options, edits, errorCode)) {
                            return;
                        }
                        titleLimit++;
                    }
                }

                /* lowercase [titleLimit..index[ */
                if(titleLimit<index) {
                    if((options&U_TITLECASE_NO_LOWERCASE)==0) {
                        /* Normal operation: Lowercase the rest of the word. */
                        toLower(caseLocale, options,
                                src, &csc, titleLimit, index,
                                sink, edits, errorCode);
                        if(U_FAILURE(errorCode)) {
                            return;
                        }
                    } else {
                        /* Optionally just copy the rest of the word unchanged. */
                        if (!ByteSinkUtil::appendUnchanged(src+titleLimit, index-titleLimit,
                                                           sink, options, edits, errorCode)) {
                            return;
                        }
                    }
                }
            }
        }

        prev=index;
    }
}

#endif

U_NAMESPACE_BEGIN
namespace GreekUpper {

UBool isFollowedByCasedLetter(const uint8_t *s, int32_t i, int32_t length) {
    while (i < length) {
        UChar32 c;
        U8_NEXT(s, i, length, c);
        int32_t type = ucase_getTypeOrIgnorable(c);
        if ((type & UCASE_IGNORABLE) != 0) {
            // Case-ignorable, continue with the loop.
        } else if (type != UCASE_NONE) {
            return TRUE;  // Followed by cased letter.
        } else {
            return FALSE;  // Uncased and not case-ignorable.
        }
    }
    return FALSE;  // Not followed by cased letter.
}

// Keep this consistent with the UTF-16 version in ustrcase.cpp and the Java version in CaseMap.java.
void toUpper(uint32_t options,
             const uint8_t *src, int32_t srcLength,
             ByteSink &sink, Edits *edits,
             UErrorCode &errorCode) {
    uint32_t state = 0;
    for (int32_t i = 0; i < srcLength;) {
        int32_t nextIndex = i;
        UChar32 c;
        U8_NEXT(src, nextIndex, srcLength, c);
        uint32_t nextState = 0;
        int32_t type = ucase_getTypeOrIgnorable(c);
        if ((type & UCASE_IGNORABLE) != 0) {
            // c is case-ignorable
            nextState |= (state & AFTER_CASED);
        } else if (type != UCASE_NONE) {
            // c is cased
            nextState |= AFTER_CASED;
        }
        uint32_t data = getLetterData(c);
        if (data > 0) {
            uint32_t upper = data & UPPER_MASK;
            // Add a dialytika to this iota or ypsilon vowel
            // if we removed a tonos from the previous vowel,
            // and that previous vowel did not also have (or gain) a dialytika.
            // Adding one only to the final vowel in a longer sequence
            // (which does not occur in normal writing) would require lookahead.
            // Set the same flag as for preserving an existing dialytika.
            if ((data & HAS_VOWEL) != 0 && (state & AFTER_VOWEL_WITH_ACCENT) != 0 &&
                    (upper == 0x399 || upper == 0x3A5)) {
                data |= HAS_DIALYTIKA;
            }
            int32_t numYpogegrammeni = 0;  // Map each one to a trailing, spacing, capital iota.
            if ((data & HAS_YPOGEGRAMMENI) != 0) {
                numYpogegrammeni = 1;
            }
            // Skip combining diacritics after this Greek letter.
            int32_t nextNextIndex = nextIndex;
            while (nextIndex < srcLength) {
                UChar32 c2;
                U8_NEXT(src, nextNextIndex, srcLength, c2);
                uint32_t diacriticData = getDiacriticData(c2);
                if (diacriticData != 0) {
                    data |= diacriticData;
                    if ((diacriticData & HAS_YPOGEGRAMMENI) != 0) {
                        ++numYpogegrammeni;
                    }
                    nextIndex = nextNextIndex;
                } else {
                    break;  // not a Greek diacritic
                }
            }
            if ((data & HAS_VOWEL_AND_ACCENT_AND_DIALYTIKA) == HAS_VOWEL_AND_ACCENT) {
                nextState |= AFTER_VOWEL_WITH_ACCENT;
            }
            // Map according to Greek rules.
            UBool addTonos = FALSE;
            if (upper == 0x397 &&
                    (data & HAS_ACCENT) != 0 &&
                    numYpogegrammeni == 0 &&
                    (state & AFTER_CASED) == 0 &&
                    !isFollowedByCasedLetter(src, nextIndex, srcLength)) {
                // Keep disjunctive "or" with (only) a tonos.
                // We use the same "word boundary" conditions as for the Final_Sigma test.
                if (i == nextIndex) {
                    upper = 0x389;  // Preserve the precomposed form.
                } else {
                    addTonos = TRUE;
                }
            } else if ((data & HAS_DIALYTIKA) != 0) {
                // Preserve a vowel with dialytika in precomposed form if it exists.
                if (upper == 0x399) {
                    upper = 0x3AA;
                    data &= ~HAS_EITHER_DIALYTIKA;
                } else if (upper == 0x3A5) {
                    upper = 0x3AB;
                    data &= ~HAS_EITHER_DIALYTIKA;
                }
            }

            UBool change;
            if (edits == nullptr && (options & U_OMIT_UNCHANGED_TEXT) == 0) {
                change = TRUE;  // common, simple usage
            } else {
                // Find out first whether we are changing the text.
                U_ASSERT(0x370 <= upper && upper <= 0x3ff);  // 2-byte UTF-8, main Greek block
                change = (i + 2) > nextIndex ||
                        src[i] != getTwoByteLead(upper) || src[i + 1] != getTwoByteTrail(upper) ||
                        numYpogegrammeni > 0;
                int32_t i2 = i + 2;
                if ((data & HAS_EITHER_DIALYTIKA) != 0) {
                    change |= (i2 + 2) > nextIndex ||
                            src[i2] != (uint8_t)u8"\u0308"[0] ||
                            src[i2 + 1] != (uint8_t)u8"\u0308"[1];
                    i2 += 2;
                }
                if (addTonos) {
                    change |= (i2 + 2) > nextIndex ||
                            src[i2] != (uint8_t)u8"\u0301"[0] ||
                            src[i2 + 1] != (uint8_t)u8"\u0301"[1];
                    i2 += 2;
                }
                int32_t oldLength = nextIndex - i;
                int32_t newLength = (i2 - i) + numYpogegrammeni * 2;  // 2 bytes per U+0399
                change |= oldLength != newLength;
                if (change) {
                    if (edits != NULL) {
                        edits->addReplace(oldLength, newLength);
                    }
                } else {
                    if (edits != NULL) {
                        edits->addUnchanged(oldLength);
                    }
                    // Write unchanged text?
                    change = (options & U_OMIT_UNCHANGED_TEXT) == 0;
                }
            }

            if (change) {
                ByteSinkUtil::appendTwoBytes(upper, sink);
                if ((data & HAS_EITHER_DIALYTIKA) != 0) {
                    sink.AppendU8(u8"\u0308", 2);  // restore or add a dialytika
                }
                if (addTonos) {
                    sink.AppendU8(u8"\u0301", 2);
                }
                while (numYpogegrammeni > 0) {
                    sink.AppendU8(u8"\u0399", 2);
                    --numYpogegrammeni;
                }
            }
        } else if(c>=0) {
            const UChar *s;
            c=ucase_toFullUpper(c, NULL, NULL, &s, UCASE_LOC_GREEK);
            if (!appendResult(nextIndex - i, c, s, sink, options, edits, errorCode)) {
                return;
            }
        } else {
            // Malformed UTF-8.
            if (!ByteSinkUtil::appendUnchanged(src+i, nextIndex-i,
                                               sink, options, edits, errorCode)) {
                return;
            }
        }
        i = nextIndex;
        state = nextState;
    }
}

}  // namespace GreekUpper
U_NAMESPACE_END

static void U_CALLCONV
ucasemap_internalUTF8ToLower(int32_t caseLocale, uint32_t options, UCASEMAP_BREAK_ITERATOR_UNUSED
                             const uint8_t *src, int32_t srcLength,
                             icu::ByteSink &sink, icu::Edits *edits,
                             UErrorCode &errorCode) {
    UCaseContext csc=UCASECONTEXT_INITIALIZER;
    csc.p=(void *)src;
    csc.limit=srcLength;
    toLower(
        caseLocale, options,
        src, &csc, 0, srcLength,
        sink, edits, errorCode);
}

static void U_CALLCONV
ucasemap_internalUTF8ToUpper(int32_t caseLocale, uint32_t options, UCASEMAP_BREAK_ITERATOR_UNUSED
                             const uint8_t *src, int32_t srcLength,
                             icu::ByteSink &sink, icu::Edits *edits,
                             UErrorCode &errorCode) {
    if (caseLocale == UCASE_LOC_GREEK) {
        GreekUpper::toUpper(options, src, srcLength, sink, edits, errorCode);
    } else {
        UCaseContext csc=UCASECONTEXT_INITIALIZER;
        csc.p=(void *)src;
        csc.limit=srcLength;
        toUpper(
            caseLocale, options,
            src, &csc, srcLength,
            sink, edits, errorCode);
    }
}

static void U_CALLCONV
ucasemap_internalUTF8Fold(int32_t /* caseLocale */, uint32_t options, UCASEMAP_BREAK_ITERATOR_UNUSED
                          const uint8_t *src, int32_t srcLength,
                          icu::ByteSink &sink, icu::Edits *edits,
                          UErrorCode &errorCode) {
    toLower(
        -1, options,
        src, nullptr, 0, srcLength,
        sink, edits, errorCode);
}

void
ucasemap_mapUTF8(int32_t caseLocale, uint32_t options, UCASEMAP_BREAK_ITERATOR_PARAM
                 const char *src, int32_t srcLength,
                 UTF8CaseMapper *stringCaseMapper,
                 icu::ByteSink &sink, icu::Edits *edits,
                 UErrorCode &errorCode) {
    /* check argument values */
    if (U_FAILURE(errorCode)) {
        return;
    }
    if ((src == nullptr && srcLength != 0) || srcLength < -1) {
        errorCode = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    // Get the string length.
    if (srcLength == -1) {
        srcLength = (int32_t)uprv_strlen((const char *)src);
    }

    if (edits != nullptr && (options & U_EDITS_NO_RESET) == 0) {
        edits->reset();
    }
    stringCaseMapper(caseLocale, options, UCASEMAP_BREAK_ITERATOR
                     (const uint8_t *)src, srcLength, sink, edits, errorCode);
    sink.Flush();
    if (U_SUCCESS(errorCode)) {
        if (edits != nullptr) {
            edits->copyErrorTo(errorCode);
        }
    }
}

int32_t
ucasemap_mapUTF8(int32_t caseLocale, uint32_t options, UCASEMAP_BREAK_ITERATOR_PARAM
                 char *dest, int32_t destCapacity,
                 const char *src, int32_t srcLength,
                 UTF8CaseMapper *stringCaseMapper,
                 icu::Edits *edits,
                 UErrorCode &errorCode) {
    /* check argument values */
    if(U_FAILURE(errorCode)) {
        return 0;
    }
    if( destCapacity<0 ||
        (dest==NULL && destCapacity>0) ||
        (src==NULL && srcLength!=0) || srcLength<-1
    ) {
        errorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    /* get the string length */
    if(srcLength==-1) {
        srcLength=(int32_t)uprv_strlen((const char *)src);
    }

    /* check for overlapping source and destination */
    if( dest!=NULL &&
        ((src>=dest && src<(dest+destCapacity)) ||
         (dest>=src && dest<(src+srcLength)))
    ) {
        errorCode=U_ILLEGAL_ARGUMENT_ERROR;
        return 0;
    }

    CheckedArrayByteSink sink(dest, destCapacity);
    if (edits != nullptr && (options & U_EDITS_NO_RESET) == 0) {
        edits->reset();
    }
    stringCaseMapper(caseLocale, options, UCASEMAP_BREAK_ITERATOR
                     (const uint8_t *)src, srcLength, sink, edits, errorCode);
    sink.Flush();
    if (U_SUCCESS(errorCode)) {
        if (sink.Overflowed()) {
            errorCode = U_BUFFER_OVERFLOW_ERROR;
        } else if (edits != nullptr) {
            edits->copyErrorTo(errorCode);
        }
    }
    return u_terminateChars(dest, destCapacity, sink.NumberOfBytesAppended(), &errorCode);
}

/* public API functions */

U_CAPI int32_t U_EXPORT2
ucasemap_utf8ToLower(const UCaseMap *csm,
                     char *dest, int32_t destCapacity,
                     const char *src, int32_t srcLength,
                     UErrorCode *pErrorCode) {
    return ucasemap_mapUTF8(
        csm->caseLocale, csm->options, UCASEMAP_BREAK_ITERATOR_NULL
        dest, destCapacity,
        src, srcLength,
        ucasemap_internalUTF8ToLower, NULL, *pErrorCode);
}

U_CAPI int32_t U_EXPORT2
ucasemap_utf8ToUpper(const UCaseMap *csm,
                     char *dest, int32_t destCapacity,
                     const char *src, int32_t srcLength,
                     UErrorCode *pErrorCode) {
    return ucasemap_mapUTF8(
        csm->caseLocale, csm->options, UCASEMAP_BREAK_ITERATOR_NULL
        dest, destCapacity,
        src, srcLength,
        ucasemap_internalUTF8ToUpper, NULL, *pErrorCode);
}

U_CAPI int32_t U_EXPORT2
ucasemap_utf8FoldCase(const UCaseMap *csm,
                      char *dest, int32_t destCapacity,
                      const char *src, int32_t srcLength,
                      UErrorCode *pErrorCode) {
    return ucasemap_mapUTF8(
        UCASE_LOC_ROOT, csm->options, UCASEMAP_BREAK_ITERATOR_NULL
        dest, destCapacity,
        src, srcLength,
        ucasemap_internalUTF8Fold, NULL, *pErrorCode);
}

U_NAMESPACE_BEGIN

void CaseMap::utf8ToLower(
        const char *locale, uint32_t options,
        StringPiece src, ByteSink &sink, Edits *edits,
        UErrorCode &errorCode) {
    ucasemap_mapUTF8(
        ustrcase_getCaseLocale(locale), options, UCASEMAP_BREAK_ITERATOR_NULL
        src.data(), src.length(),
        ucasemap_internalUTF8ToLower, sink, edits, errorCode);
}

void CaseMap::utf8ToUpper(
        const char *locale, uint32_t options,
        StringPiece src, ByteSink &sink, Edits *edits,
        UErrorCode &errorCode) {
    ucasemap_mapUTF8(
        ustrcase_getCaseLocale(locale), options, UCASEMAP_BREAK_ITERATOR_NULL
        src.data(), src.length(),
        ucasemap_internalUTF8ToUpper, sink, edits, errorCode);
}

void CaseMap::utf8Fold(
        uint32_t options,
        StringPiece src, ByteSink &sink, Edits *edits,
        UErrorCode &errorCode) {
    ucasemap_mapUTF8(
        UCASE_LOC_ROOT, options, UCASEMAP_BREAK_ITERATOR_NULL
        src.data(), src.length(),
        ucasemap_internalUTF8Fold, sink, edits, errorCode);
}

int32_t CaseMap::utf8ToLower(
        const char *locale, uint32_t options,
        const char *src, int32_t srcLength,
        char *dest, int32_t destCapacity, Edits *edits,
        UErrorCode &errorCode) {
    return ucasemap_mapUTF8(
        ustrcase_getCaseLocale(locale), options, UCASEMAP_BREAK_ITERATOR_NULL
        dest, destCapacity,
        src, srcLength,
        ucasemap_internalUTF8ToLower, edits, errorCode);
}

int32_t CaseMap::utf8ToUpper(
        const char *locale, uint32_t options,
        const char *src, int32_t srcLength,
        char *dest, int32_t destCapacity, Edits *edits,
        UErrorCode &errorCode) {
    return ucasemap_mapUTF8(
        ustrcase_getCaseLocale(locale), options, UCASEMAP_BREAK_ITERATOR_NULL
        dest, destCapacity,
        src, srcLength,
        ucasemap_internalUTF8ToUpper, edits, errorCode);
}

int32_t CaseMap::utf8Fold(
        uint32_t options,
        const char *src, int32_t srcLength,
        char *dest, int32_t destCapacity, Edits *edits,
        UErrorCode &errorCode) {
    return ucasemap_mapUTF8(
        UCASE_LOC_ROOT, options, UCASEMAP_BREAK_ITERATOR_NULL
        dest, destCapacity,
        src, srcLength,
        ucasemap_internalUTF8Fold, edits, errorCode);
}

U_NAMESPACE_END